NCLE Advanced Certification Exam
The answer is D. The re are six ocular muscles: medial rectus, lateral rectus, superior rectus, inferior rectus, superior oblique and inferior oblique.
108. Which of the following is not one of the six ocular muscles? A. Medial Rectus B. Superior Oblique C. Superior Rectus D. Intermediate Tensile
The answer is A. Of the options listed, only increasing the lens' center thickness will consistently reduce the flexure of the lens during the blink. Decreasing the lens diameter or steepening the base curve may even increase the lens flexure.
175. Performing keratometry over a rigid gas permeable lens indicates that the lens is flexing on the blink. What can be done to reduce the flexure? A. Increase center thickness B. Decrease the overall lens diameter C. Steepen the base curve D. Use a myoflange edge design
The answer is A. A lens is truncated by removing a segment of the lower edge of a contact lens. This creates a straight edge that interacts with the lower lid and aids in lens positioning. Of the lens designs listed in the question, the only one that requires precise positioning of its optical portions is a translating bifocal lens.
2. A truncation is used on a rigid gas permeable contact lens to help enhance the performance of which type of design? A. Bifocal B. Aphakic C. Bitoric D. Keratoconus
The answer is A. Patient complaints are never an easy event to handle. But, the more timely they are dealt with, the less complicated they will become. It is best to handle patient complaints discreetly, away from the hearing of other patients. While refunds may be a part of resolving the complaint, it is not always the cause of the problem, nor the appropriate solution. Listening calmly to the entire complaint, empathizing with the patient and reassuring them will all help to resolve the problem in a positive way.
207. Patient complaints should be handled: A. Immediately B. By returning money C. At the end of the month D. Once a week
The answer is D. When adding a spherical over-refraction to a bitoric lens, it must be added to both meridians Example: -1.00 / -4.50 -1.00 / -1.00 -2.00 / -5.50
27. Lens specifications in actual drum readings: 43.50/45.50 -1.00/-4.50 9.2 Over-refraction: -1.00 sphere What is the new lens power? A. plano/-3.50 B. -1.00/-5.50 C. -2.00/-4.50 D. -2.00/-5.50
The answer is D. Decreasing the height of the bifocal segment is the only option that will drop the seg and alleviate the visual confusion caused by the segment bisecting the pupil. All of the other options will move the bifocal segment further up into the line of vision.
28. A translating bifocal wearer complains of blur at distance. Upon slit lamp exam, you notice that the bifocal segment bisects the pupil. In order to improve this situation, you should: A. Increase the seg height B. Decrease truncation C. Decrease prism ballast D. Decrease seg height
The answer is B. A lenticular or myoflange design will decrease the mass of an aphakic lens as well as increase the edge profile, which allows it to interact more with the upper lid and aid in positioning of the lens.
3. The mass of an aphakic rigid gas permeable contact lens can be reduced by making the lens design: A. Spherical B. Lenticular C. Tricurve D. Aspheric
The answer is B. The Rose K, McGuire and Soper lenses are all designs specifically created for the keratoconus eye, with steeper, smaller optical zone diameters and customized peripheral curve systems to improve the fit on the unique corneal topography of a keratoconic eye.
30. Rose K, McGuire and Soper are all different types of which lens design? A. Post-refractive surgery B. Keratoconus C. Torie D. Aspheric
The answer is C. Oxygen transmissibility is useful clinically as an indication of oxygen delivery. This is because it represents the amount of oxygen moving through a specific lens with a given thickness instead of simply the oxygen moving through a plastic of unknown thickness, since the oxygen delivery will vary according to the thickness of the lens.
35. Dk/t is: A. Oxygen Permeability B. Lens Thickness C. Oxygen Transmissibility D. Specific Gravity
The answer is D. When a rigid gas permeable lens flexes on the eye, the patient will notice a number of phenomena. The most obvious is the fluctuation in vision that occurs during the blink. Continuous flexing of the lens on the eye may also result in a lens that warps over time and can lead to decreased comfort.
38. Higher Dk materials and high minus prescriptions present a greater chance for the contact lens to flex excessively on the eye. This may result in which of the following situations? A. Variable acuity B. Discomfort C. Warped central posterior curve D. All of the above
The answer is B. Increasing the optical zone diameter and increasing the overall lens diameter will both tighten and steepen the relationship of the lens to the cornea. Decreasing the optic zone diameter will serve to flatten and loosen the lens to cornea relationship. Using a prism-ballasted lens design will not affect the lens to cornea relationship as it relates to sagittal depth.
4. In order to tighten the fit of a rigid gas permeable lens you can: I. Increase the optical zone diameter 2. Decrease the optical zone diameter 3. Increase the overall lens diameter 4. Use a prism ballasted lens design A. 3 only B. 1&3 C. 2 only D. 2&3
The answer is B. An inverted or flat fitting lens will often display edge lift or stand off.
42. The thickness of a soft contact lens will affect the: A. Oxygen transmissibility of the lens B. Power C. Opaque Tint D. Patients visual acuity
The answer is D. A hyperflange will decrease edge thickness as well as lens awareness . Aspheric peripheral curves change the posterior design of the lens but do not reduce edge thickness. A higher Dk material will not change the overall lens edge thickness. A myoflange will actually add thickness to the lens edge and is used for high plus lenses not high minus lenses.
5. A high minus rigid gas permeable lens will be thin centrally with relatively thick edges. To reduce the edge thickness, and increase overall comfort, use: A. Aspheric peripheral curves B. A myoflange C. A higher Dk material D. A hyperflange
50. The answer is C. When considering sagittal depth, if the base curves of the lenses are the same, the smaller the diameter, the shorter the depth. This indicates that the 14.0 diameters are looser than the 14.5 diameters. If the lens diameters are equal, the flatter the base curve, the looser the lens. Therefore, the 8.8 would be flatter than the 8.4 and confirms that the 8.8 base curve with the 14.0 diameter would most loosely fit of the choices given.
50. Which of the following soft lenses would you expect to fit the loosest on the eye if the lens material and design are all the same? A. 8.4/14.0 B. 8.4/14.5 C. 8.8/14.0 D. 8.8/14.5
The answer is B. The increased water content allows for a greater exchange of oxygen through the lens material and is the reason they are approved for extended wear.
78. Another term for modulus is? A. Wettability B. Durability C. Stiffness D. Wearability
D. Stroma
Ch1-1. Which layer of the cornea makes up 10% of the structure's total thickness? A. Epithelium B. Bowman's membrane C. Endothelium D. Stroma
The answer is B. Values that are higher than 7.4 are considered relatively alkaline. Values that are lower than 7.4 may be considered more acidic.
The average pH of the tear film is: A. 7.20 B. 7.45 C. 7.85 D. 8.25
The answer is A. The radiuscope is also referred to as an optic spherometer. The ophthalmoscope is used by eye care practitioners to view a patient's fundus. The keratometer is an instrument used to measure the curvature of the central cornea. The biomicroscope is another name for a slit lamp.
131. A radiuscope is sometimes referred to as a(n): A. Optic spherometer B. Ophthalmoscope C. Keratometer D. Biomicroscope
The answer is B. Myopia or nearsightedness is the condition that occurs when the light rays come to a focus in front of the retina.
133. Which term describes the condition when light rays come into a single focus in front of the retina? A. Hyperopia B. Myopia C. Astigmatism D. Presbyopia
The answer is A. Lenses that position temporally or inferiorly are not typically indicated and should be avoided. Lenses that position superiorly are often lenses that have been designed with the apical alignment philosophy and have been fit flatter than the flattest keratometer reading in order to achieve this alignment. Lenses that are fit with apical clearance are fit steeper than the flattest corneal measurement and often will fit intrapalpebrally or centrally.
16. To achieve a lens to cornea relationship that exhibits apical clearance, the lens is designed steeper than the flattest corneal measurement. This lens will most often position: A. Centrally B. Temporally C. Superiorly D. Inferiorly
The answer is B. Pachymetry is considered the definitive tool for measuring corneal thickness. Specular microscopy will assess the morphologic changes in the corneal endothelium. Corneoscopy is a method of interpreting the corneal curvature. A thickness gauge measures the thickness of a rigid contact lens.
187. Which of the following methods best measures corneal thickness? A. Specular microscopy B. Pachymetry C. Corneoscopy D. Thickness gauge
The answer is D. The dating or shelf life of a lens is determined by the lens manufacturer and the Food and Drug Administration (FDA). Contact lenses are a regulated product and should be discarded when beyond the designated dating. Proper inventory monitoring should reveal outdated products to assure they do not end up on the patient's eye.
202. Final lens parameters have been determined for the patient. But, when retrieving the new, unopened lenses from inventory you notice that the date on the vials has expired. You should: A. Clean and disinfect prior to dispensing B. Get approval from the referring doctor to extend the expiration date C. See if it is satisfactory with the patient prior to dispensing D. Reorder new lenses
The answer is B. Patient retention is a hot topic in these competitive times. It has been found that sched- uling the patient's next appointment before they leave, sending out reminder post cards, as well as calling the patient the day before an appointment will help to make the best use of your office time as well as keep the patient in your practice.
203. Pre-scheduling appointments, telephone reminders about upcoming appointments and reminder postcards are all means of enhancing: A. Advertising B. Patient retention C. Telephone skills D. Computer management
The answer is C. Fixed assets refer to furniture, equipment and property that is owned by the practice. These assets are depreciated or amortized. Liabilities are claims or bills that the practice owes. Accounts payable are a type of liability and represent the bills that the practice has for goods or services that it receives. Long-term debt, also a liability, is debt that is not due for more than a year, for example, a mortgage.
217. "Fixed assets" refers to: A. Liabilities B. Accounts payable C. Furniture, property D. Longterm debt
The answer is C. Tint is the only characteristic listed that does not influence the fit of a soft contact lens. Changes in diameter, water content or sagittal depth will affect the soft lens fit.
47. Which characteristic of a soft lens does not affect the fit? A. Diameter B. Sagittal depth C. Tint D. Water content
The answer is A. A spin cast soft lens is created with a constant anterior (outside) curve. It is the posterior curve that changes as the power of the lens changes.
69. Where is the power curve on a spin cast soft lens? A. Posterior surface B. Anterior surface C. Astigmatic surface D. On the edge
The answer is D. In cases of bullous keratopathy, nystagmus and against the rule astigmatism, the patient will do quite well with a soft contact lens. In cases of bullous keratopathy, a soft lens may even be used as a bandage to improve the patient's comfort. In nystagmus, the patient is often more comfortable with a soft lens physically and visually due to the rapid eye movements characteristic of that condition. Many practitioners prefer to fit soft lenses on patients whose astigmatism is against the rule since a rigid lens may tend to displace laterally in that situation. However, in cases of irregular astigmatism, the most appropriate option for the patient is a rigid lens material.
73. A soft contact lens can be successfully used in each of the following cases except: A. Bullous keratopathy B. Nystagmus C. Against the rule astigmatism D. Irregular astigmatism
The answer is B. With advances in manufacturing, disposables have become more affordable, more reproducible and are an extremely effective solution to the problem of GPC and heavy deposits. Extended wear of lenses will only increase the problem of deposits and GPC. CAB (cellulose acrylate butyrate) is a rigid gas permeable material.
74. The major concern in using silicone as a contact lens material is it's? A. Hydrophilic nature B. Optics C. Hydrophobic nature D. Oxygen transmission
C. photorefractive keratectomy.
Ch11-12. PRK stands for A. photo radial keratectomy. B. photorefractive keratomileusis. C. photorefractive keratectomy. D. photorefractive keratoplasty.
B. four
Ch13-14. There are ______ major types of aberrometers. A. three B. four C. five D. six
A. at the eyelid margins.
Ch2-5. The meibomian glands are located A. at the eyelid margins. B. at the limbal margins. C. in the conjunctiva. D. near the puncta.
C. cranial nerve V
Ch2-6. Aqueous tears are secreted mainly reflexively via stimulation of _______ nerve endings. A. cranial nerve II B. cranial nerve X C. cranial nerve V D. cranial nerve VII
B. 1mm
Ch2-7. Inspection of the tear meniscus between the globe and the lower lid should reveal a normal tear film to be approximately _______ in height. A. 3mm B. 1mm C. 5mm D. 0.1mm
A. 10
Ch2-8. A tear break-up time (TBUT) of less than _____ seconds is considered abnormal. A. 10 B. 12 C. 14 D. 16
C. retinal detachment.
Ch2-9. Slit-lamp biomicroscopic examination of the conjunctiva and cornea prior to contact lens fitting is appropriate to examine for any signs of the following except A. inflammation and corneal dryness. B. chemosis. C. retinal detachment. D. corneal infiltrates.
D. uniquely, outside
Ch3-1. Custom soft contact lenses are lenses manufactured for a specific patient with parameters that are typically ______ that range of standard, mass-produced, inventorial lenses. A. individually, within B. mass, outside C. mass, within D. uniquely, outside
C. Keraclear B1.
Ch3-10. Soft contact lens designs for corneal ectasia include all of the following except, A. Flexlens Tri-Curve. B. Hydrokone. C. Keraclear B1. D. Kerasoft IC.
C. 14.0-14.2mm.
Ch3-2. Most mass-produced lenses have standard diameters set at approximately A. 11.5-11.Smm. B. 12.0-12.3mm. C. 14.0-14.2mm. D. 14.8-15.lmm.
A. 11.8mm, 12.0mm
Ch3-3. In a study done at Pacific University, researchers topographically measured the HVIDs of 200 corneas and found the average corneal diameter to be __ and __ to be the most frequent diameter. A. 11.8mm, 12.0mm B. 12.3mm, 12.5mm C. 12.8mm, 13.0mm D. 13.2mm, 13.5mm
B. 1.0mm
Ch3-4. When fitting a custom soft contact lens, a drape from cornea onto limbus is desirable. A. 0.5mm B. 1.0mm C. 2.0mm D. 3.0mm
B. discomfort, reduced
Ch3-5. Traditionally, persons with irregular corneas have been limited to gas permeable contact lenses, which sometimes resulted in and __ wearing time. A. increased comfort, reduced B. discomfort, reduced C. discomfort, increased D. increased comfort, increased
D. 8.0mm
Ch3-9. The central optic zone traditionally encompasses the central ____ of the contact lens. A. 11.0mm B. 10.0mm C. 9.0mm D. 8.0mm
D. 30 minutes
Ch5-4. Lenses that are designed to vault the cornea and have their fitting zone supported by the conjunctiva/sclera should be allowed to settle for at least before the clearance values between the cornea and the lens are estimated. A. 5 minutes B. 15 minutes C. 20 minutes D. 30 minutes
A. both the cornea and the sclera.
Ch5-5. Corneo-scleral and semi-scleral lenses are designed to have landing zones on A. both the cornea and the sclera. B. the cornea only. C. the limbus only. D. the sclera only.
A. the highest oxygen permeable materials
Ch5-6. When fitting scleral contact lenses, ______ should be used. A. the highest oxygen permeable materials B. mid-range oxygen permeable materials C. low-range oxygen permeable materials D. very low oxygen permeable materials
C. 1 month
Ch5-7. An opened solutions bottle should be discarded according to manufacturer's instruction-usually in less than A. 1 week. B. 2 weeks. C. 1 month. D. 3 months.
B. plunger devices.
Ch5-8. Application and removal of scleral lenses usually necessitates the use of A. fingers only. B. plunger devices. C. fingers and holders. D. both fingers and thumb.
C. 2 weeks.
Ch8-3. The Orthokeratology process for full correction may take as long as A. 2 days. B. 7 days. C. 2 weeks. D. 4 weeks.
A. Joseph A. Baldone, MD
Ch4-1. In the early l 970's, __ pioneered the idea of placing a gas permeable lens (then PMMA) over a hydrogel soft lens in keratoconic patients. This concept would be known as piggybacking. A. Joseph A. Baldone, MD B. Whitney G. Sampson, MD C. Oliver H Dabezies, Jr., MD D. Samuel Jackson, MD
The answer is D. The posterior optical zone will directly affect the lens to cornea relationship of a rigid gas permeable lens. If the posterior optical zone is steepened, it will increase the sagittal depth. If it is flattened, it will decrease the sagittal depth. Changing the power, which is accomplished by changing the anterior optical zone, will not affect the sagittal depth of the lens, nor will changing its edge design.
1. The sagittal depth of a rigid gas permeable contact lens can be altered without changing the diameter by: A. Changing the power B. Changing the edge design C. Changing the radius of curvature of the anterior optical zone D. Changing the radius of curvature of the posterior optical zone
The answer is C. Lenticular astigmatism usually exists when the amount of refractive cylinder is greater than the amount of corneal cylinder. It is assumed that the additional astigmatism originates in the crystalline lens.
10. If a patient has spherical K readings of 43.50 and an Rx of -4.00 +1.75 cx 90, the patient has: A. Corneal astigmatism B. Against the rule astigmatism C. Lenticular astigmatism D. Mixed astigmatism
The answer is B. The bulk of the tear film is produced by the main lacrimal gland and the accessory lacrimal glands of Krauss and Wolfring. These glands lie in the conjunctiva of the fornix predominantly superiorly. The majority of Iacrimal fluid enters the fomices superotemporally. The glands of Zeiss and Moll are sebaceous and sweat glands. Meibomian glands are responsible for producing the lipid layer of the tear film. The Crypts of Henle are mucous membrane folds, lined by the epithelium and are part of the palpebral conjunctiva.
100. The aqueous layer of the tear film is produced by: A. Crypts of Henle B. Lacrimal glands C. Glands of Zeiss and Moll 0. Meibomian gland
The answer is B. The epithelium is constantly regenerating and replacing cells that are lost and it is this cellular reproduction that requires the significant energy provided by large amounts of oxygen. The endothelium does not reproduce and therefore does not require as much oxygen as the epithelium.
101. Why does the epithelium consume more oxygen than the endothelium? A. Because it has easier access to oxygen through the tear and the environment B. The·epithelium needs: the energy oxygen provides to regenerate C. The endothelium is fed through nutrients in the Aqueous fluid D. They both consume the same amount of oxygen
The answer is C. Pleomorphism refers to a change in shape of the corneal endothelial cells. Polymegathism refers to changes in size of the endothelial cells. A normal endothelial cell pattern is honeycomb shaped and consistent in size.
102. Pleomorphism is: A. Sloughing off of the epithelial cells B. Splitting of epithelial cells C. Variation in the shape of endothelial cells D. Variation in the size of endothelial cells
The answer is A. Discontinuing lens wear increases the epithelium's metabolic function. The deeper layers of disorganized epithelial tissues are brought to the surface, causing more microcysts to appear. Complete resolution may take several months.
104. You observe epithelial microcysts on a contact lens patient and have discontinued the patient's lens wear. Upon rechecking the patient in the next 2 to 4 weeks, you observe: A. More microcysts B. Less microcysts C. No microcysts (complete resolution) D. No change the microcysts will always be there
The answer is B. The cornea is one of the few avascular tissues in the body and yet is one of the most heavily innervated and sensitive tissues.
105. Pinpoint lesions on the cornea that stain with fluorescein are often indicative of: A. Superficial punctate keratitis B. Microbial keratitis C. Superior arcuate epithelial lesions D. Superior limbic keratonconjunctivitis
The answer is D. The tear film is an invaluable part of the overall optical system. It provides protection from dehydration, a smooth optical surface, and nutrients for the cornea all in a very thin layer. The entire tear film is only 7 microns thick with the aqueous layer comprising about 98% of this vital fluid. The lipid layer is only 0.1 micron thick and the mucin layer 0.2 to 0.5 microns thick.
106. The thickness of the tear film is: A. 0.007 microns B. 0.07 microns C. 0.7 microns D. 7 microns
The answer is C. The Palisades of Vogt are a series of ridges that are found in the limbus radiating out from the cornea. The tarsal plate is the underside of the eyelid and the fornix is the cul-de-sac formed by the bulbar and palpebral conjunctiva.
107. The Palisades of Vogt are a series of ridges that are found in the: A. Tarsal plate B. Epithelium C. Limbus D. Fornix
The answer is B. The index of refraction of the cornea is 1.376. The keratometer works on an index of refraction of 1.3375.
109. The refractive index of the cornea is: A. 1.234 B. 1.376 C. 1.415 D. 1.524
The answer is B. With regular astigmatism, even high degrees, a soft toric lens can work quite effectively. Presbyopic and aphakic patients can also be successfully fit with soft lenses. However, patients with irregular astigmatism will achieve their best visual acuity only with rigid gas permeable lenses since soft lenses will mold to the corneal contour and not mask the irregularity.
11. In which of the following situations is a rigid gas permeable lens always preferred over a soft lens? A. Regular astigmatism B. Irregular astigmatism C. Aphakia D. Presbyopia
The answer is B. The eye responds to a specific range of light waves which includes those found in the components of white light. The retina with its cones and rods reacts differently to each color in the spectrum of visible or white light. Each cone can transmit a separate impulse. Infrared and ultraviolet are portions of the spectrum that are invisible to the human eye and can cause damage to some of its areas.
110. The eye can visualize that portion of the radiant energy spectrum that includes: A. Infrared, white and ultraviolet radiations B. All of the components of white light C. Infrared and white radiation D. Ultraviolet and white radiations
The answer is A. Central vision is predominantly cone vision. The cone receptors are the only receptors found in the fovea, which is the central pit in the macula (which surrounds the fovea). As the periphery of the retina is approached, the number of cones diminish and the number of rods increase. Cones are responsible for color vision; rods for black and white and seeing in dim illumination
111. Peripheral vision is chiefly the function of the: A. Rods B. Macula C. Cones D. Fovea
The answer is A. Blepharitis is an inflammation of the lid margins. It includes scaling and flaking, as well as loss of lashes and errant lashes in the most severe cases. Ectropion is an outward turning of the eyelid. Entropion is an inward turning of the eyelid. Ptosis is a drooping of the upper lid.
112. Which of the following lid conditions occurs most frequently? A. Blepharitis B. Ectropion C. Entropion D. Ptosis
The answer is A. Blepharitis can be controlled by lid hygiene and can often be successfully managed by the patient. Ectropion and entropion can only be resolved by surgery. Ptosis, depending on the underlying cause, will need medical or surgical intervention to be resolved.
113. Which of the following conditions can be managed by the patient? A. Blepharitis B. Ectropion C. Entropion D. Ptosis
The answer is D. A rigid gas permeable lens is significantly affected by the position and tautness of the lids. If a lid droops, as it does in ptosis, it may affect the position of the lens on the cornea. Glaucoma, keratitis sicca and blepharitis may all affect the choice of the lens material, but none would affect the lens position on the eye.
114. Which of the following will have the greatest impact on the positioning of an RGP contact lens? A. Blepharitis B. Keratitis Sicca C. Glaucoma D. Ptosis
The answer is D. Infiltrates are groups of white blood cells that migrate into corneal tissue as a response to disease or infection. Lipids and protein are found in the tear film. Red blood cells most commonly enter the cornea through vascularization.
115. A corneal infiltrate is comprised of: A. Red blood cells B. Protein C. Lipids D. White blood cells
The answer is D. Endocrine changes in patients are often subtle and difficult to manage. Patients who are pregnant and those who are going through menopause will often have symptoms that lead to a decrease in wearing time. Among those symptoms are drier eyes which can be caused by a reduced tear volume; corneal desensitivity and an increase in corneal thickness, which may cause blurry vision and discomfort. It is believed that retention of fluid throughout the body is evident in the cornea as well, leading to slight changes in keratometry.
116. Which of these problems is least likely to occur in patients who are pregnant or going through menopause? A. Decreased tear functions B. Retention of fluid leading to corneal shape changes C. Blurred vision D. Increased corneal sensitivity
The answer is D. Thyroid diseases such as hyperthyroidism, hypothyroidism and Grave's disease, often cause subtle changes in the body even before a positive diagnosis is made. This can lead to problems wearing contact lenses, such as decreased and altered tear film and decreased wearing time.
117. Which of the following can occur in patients who have thyroid disease? A. Decreased tear function B. Decreased wearing time C. Increased mucin and lipid tear components that can cause lenses to adhere D. Increased tear function
The answer is A. Aniridia and an iridectomy represent one natural and one surgical condition that result in the total or partial absence of the iris. Since the iris is responsible for controlling the amount of light that enters the eye, when part or all of it is missing, the patient experi- ences a great deal of photophobia. A painted iris contact lens will help shield the eye from excessive amounts of light.
118. Which of the following eye conditions may require a cosmetic painted iris contact lens? A. Aniridia or iridectomy B Iritis or rubeosis C. Iridectomy or uveitis D. Aniridia or rubeosis
The answer is C. White blood cells will invade the cornea in cases of viral infections or toxic reactions to solutions as well as a number of other situations. Retinal detachments are not known to cause corneal infiltrates, nor is Kruckenberg's Spindle. Kruckenberg's Spindle consists of spindle-shaped pigment deposits found on the central corneal endothelium. It is more prevalent in males, and is often found with pigment dispersion glaucoma· or following uveitis. Pupil infections are not real and cannot occur as the pupil through which light travels on its ways to the retina is not a physical structure.
119. Corneal infiltrates may be present as a result of which of the following conditions? A. Viral infections or retinal detachments B. Toxic reactions to solutions or Kruckenberg's Spindle C. Viral infections or toxic reactions to solutions D. Retinal detachments or pupil infections
The answer is A. Decreasing the optical zone diameter while steepening the base curve of a rigid gas permeable lens will allow the lens to cornea relationship to remain the same, since decreasing the optical zone diameter loosens the lens to cornea relationship and steepen- ing the base curve tightens the relationship. Increasing the overall lens diameter also tightens the fit and will only exaggerate the change made to the lens to cornea relationship. Decreasing the center thickness or increasing the lens power will have no significant effect on the relationship of the lens to the cornea.
12. In order to steepen the base curve of a rigid gas permeable lens without changing the lens to cornea relationship, you would also need to: A. Decrease the optical zone diameter B. Decrease the center thickness C. Increase the overall lens diameter D. Increase the lens power
The answer is B. Red green color blind patients may benefit from an X Chrome lens, which is a ruby red lens worn in the non-dominant eye. This lens may aid in increasing the discrimination of colors, although the person will not achieve normal color vision.
120. The inability to completely close the eyes during a blink is known as: A. Lagophthalmos B. Ptosis C. Floppy lid syndrome D. Bell's Phenomena
The answer is D. The refractive power of the cornea is a function of its radius of curvature. Most cornea's have a central curvature of 40 to 48 diopters, reflecting the power of the cornea.
121. The refractive power of the cornea averages: A. 10-18 Diopters B. 20-28 Diopters C. 30-38 Diopters D. 40-48 Diopters
The answer is A. Every 0.05 mm of radius equals 0.25 D. Therefore, if the base curve of the lens is changed by 0.05 mm, the power must also be changed by 0.25D.
122. For every 0.05 mm change in radius of curvature, a change in dioptric power must in made by how much? A. 0.25D B. 0.50 D C. 0.75 D D. 1.00D
The answer is C. A bitoric lens is indicated when both the corneal cylinder and refractive cylinder are significant and unequal. A front surface toric (also called an anterior surface toric) lens has a spherical back surface which is not usually used when there is more than 2.00 D of corneal cylinder. An aspheric lens may provide an acceptable lens to cornea relationship, but given the high amount of refractive cylinder, we would not expect it to provide the best option for this patient.
123. Given the following information: K's 42.75@ 180/ 45.50@ 90 Rx -1.25 -4.25 cx 180 The most appropriate rigid gas permeable lens design for this patient is: A. Aspheric B. Front surface toric C. Bitoric D. Anterior surface toric
The answer is D. The normal range of the keratometer is 36.00 D to 52.00 D, however it can be extended to 30.00 D in the flat range and 61.00 D in the steep range by adding auxiliary lenseS. To extend the range to 30.00 D, place a -1.00 D lens in front of the keratometer aperture and subtract 6.00 D from the keratometer readings. This will provide an approximate reading if a conversion chart is unavailable. To extend the range to 61.00 D, place a +1.25 D lens in front of the keratometer aperture and add 9.00 D to the keratometer readings to get an approximate reading. A conversion chart is found at the back of this book.
124. What is the normal range of the keratometer? A. 32.00 to 52.00 D B. 34.00 to 52.00 D C. 34.00 to 54.00 D D. 36.00 to 52.00 D
The answer is B. A+ 1.25 D lens held over the keratometer will add approximately nine diopters to both the vertical and horizontal meridians. For example, if a +1.25 D is held over the aperture and the resultant keratometric readings are 45.00@ 180/ 47.00 @90, add 9.00 D to both meridians. The final readings would then approximate 54.00@ 180/ 56.00@ 90.
125. A handheld lens of+ 1.25 D held in front of the keratometer can extend the range from: A. 52.00 to 58.00 D B. 52.00 to 61.00 D C. 30.00 to 36.00 D D. 32.00 to 38.00 D
The answer is B. A-1.00 D lens held over the aperture of the keratometer will offer K readings approximately 6.00 D flatter than the reading.
126. A handheld lens of -1.00 in front of the keratometer would change K readings from 38.00@ 180/ 40.00@ 90 to: A. 30.00@ 180/32 .00@90 B. 32.00@ 180/34.00@ 90 C. 44.00@ 180/ 46.00@ 90 D. 47.00@ 180/39.00 @90
The answer is A. High magnification and a thin blade of light known as an optic section will enable the fitter to view the layers of the cornea. Because the light is so sharply focused, scatter is reduced and the contrast between the sections of the cornea is maximized. The thinner the beam, the more selective the optic section and the finer the detc1ilin that section.
127. The layers of the cornea can best be viewed by using which slit lamp technique? A. Optic section B. Retro illumination C. Diffuse illumination D. Sclerotic scatter
The answer is B. Retro-illumination is achieved when the light from the slit lamp beam is focused behind the area being studied. Microcysts, tiny pockets of cellular debris, are best viewed in this format.
128. Microcysts are best viewed using which slit lamp technique? A. Optic section B. Retro illumination C. Diffuse illumination D. Sclerotic scatter
The answer is A. Viewing fluorescein patterns or fluorescein staining, can be enhanced with the use of a blue cobalt filter and the yellow Wratten filter.
129. Viewing of fluorescein can be enhanced by the additional use of: A. Blue cobalt filter and yellow Wratten filter B. Green filter C. White light and yellow Wratten filter D. Blue cobalt filter
The answer is B. Increasing the overall lens diameter or increasing the optical zone diameter will steepen the lens to cornea relationship. Conversely, decreasing the optical zone diameter, decreasing the overall lens diameter or flattening the base curve will loosen the relationship. If one change is made that tightens the relationship and another is made that loosens it, the changes will cancel each other out.
13. To steepen the lens to cornea relationship of a rigid gas permeable lens you could : A. Increase overall diameter and decrease optical zone diameter B. Increase overall diameter and increase optical zone diameter C. Increase optical zone diameter and decrease overall diameter D. Increase optical zone diameter and flatten base curve
The answer is A. While nearly every contact lens practice has a conversion table to provide this information, this problem is easily. solved if you keep in mind a few basic principles. Remember that as values for mm of radius increase, the curve becomes flatter (i.e. 7.60 mm is flatter than 7.50mm) and the opposite is true for dioptric values (i.e. 44.50 Dis flatter than 45.00 D). Use a starting point of 7.5 mm equals 45.00 D. Since 7.67 mm is a larger number, it must be flatter than 45.00 D. The only value given that is flatter than 45.00 Dis 44.00 D, so by a process of elimination, "A" should be the obvious answer. Every 0.05 mm of radius equals a change in K's of approximately 0.25 diopters.
130. 7.67 mm of radius is the same as D? A. 44.00 B. 45.50 C. 46.25 D. 48.25
The answer is B. Mixed astigmatism occurs when one meridian focuses behind the retina, and the other in front. With myopic compound astigmatism, both meridians will focus in front of the retina. Presbyopia is a loss of accommodation. Antimetropia refers to different refractive errors in each eye (i.e. one eye myopic while the other is hyperopic)
132. Without corrective lenses and with accommodation relaxed, if light enters an eye and focuses in front of and behind the retina, the patient's refractive error is: A. Antimetropia B. Mixed astigmatism C. Presbyopia D. Myopic Compound Astigmatism
The answer is A. Concave lenses are also called diverging or minimizing lenses and are used to spread out the light so it focuses further back on the retina and corrects the myopic condition.
134. What shape lens is used to correct minus refractive errors? A. Concave B. Convex C. Astigmatic D. Bifocal
The answer is A. Hyperopia or farsightedness is the condition that occurs when light rays come to a focus behind the retina.
135. What term describes the condition in which light rays come to a single focus behind the retina? A. Hyperopia B. Myopia C. Astigmatism D. Presbyopia
The answer is B. Convex lenses are used to correct hyperopia and are also called converging or magnifying lenses. These lenses will bring the light rays together more quickly and move the image from behind the retina forward to the retina.
136. What shape lens is used to correct hyperopic refractive errors? A. Concave B. Convex C. Astigmatic D. · Presbyopic
The answer is A. When more astigmatism is found in the patient's refraction than is found on the corneal surface, it is assumed that the excess astigmatism is found in the crystalline lens and is therefore, lenticular. With-the-rule astigmatism describes the type of corneal astigmatism where the horizontal meridian is flatter than the vertical meridian.
137. What term is used to describe the situation in which the astigmatic error in the refraction is greater than the amount of cylinder measured on the corneal surface? A. Lenticular astigmatism B. Corneal astigmatism C. Mixed astigmatism D. With-the-rule astigmatism
The answer is D. While the keratometer has been judged to be less than ideal for depicting a true sense of the corneal topography, an experienced contact lens professional can gather very impor- tant information about the patient. The quality of the mires will give important informa- tion about the tear film. Any distortion in the keratometric mires is a reflection of the surface quality of the cornea. Conditions such as high corneal cylinder or keratoconus, have distinct mire shapes so the appearance and quality of the mires should also be noted. Changes from baseline may be indicative of corneal molding or corneal edema.
138. When performing keratometry, the practitioner can measure the central 3 to 4 mm of the cornea, and observe all of the following except: A. Quality of mires B. Shape of mires C. Changes from baseline measurements D. Refractive astigmatism
The answer is C. The topogometer utilizes a fixation device which the patient follows as the fitter moves it along the primary meridians. This allows the fitter to scan for steeper and flatter read- ings outside the limitations of the zone measured by the standard keratometer. A Con-ta- chek is an attachment for the keratometer which allows the practitioner to measure the base curve of a rigid contact lens.
139. In order to perform corneal measurements that involve more of the entire cornea, which of the following is utilized? A. Topogometer B. Auto-refractor C. Corneal topographer D. Ophthalmoscope
The answer is D. Modification of rigid gas permeable lenses is a valuable skill and can increase a practitioner's success at RGP fitting. Many in-office modifications can be utilized to improve the positioning of a lens, reduce discomfort for the patient and eliminate corneal staining.
14. Which is not an indication for modifying a rigid gas permeable lens? A. Corneal staining B. Poor lens position C. Discomfort D. Surface Wettability
The answer is A. Using a+ 1.25 D lens over the aperture of the keratometer will extend the range of the keratometer approximately 9.00 D. If a conversion chart is not available, an estimate of the final reading can be established by adding 9.00 D to the reading.
140. An attachment is placed at the aperture of the keratometer to extend it's range beyond the 52.00 D end. If the drum reading with this extension is 46.50 D, what is the practical/ approximate corneal "K" reading? A. 55.50 D B. 56.50 D C. 57.50 D D. 58.50 D
The answer is C. The..index of refraction of the cornea is 1.376. The keratometer utilizes an index of refraction of 1.3375.
141. The index of refraction used by the keratometer is: A. 0.13375 B. 0.3375 C. 1.3375 D. 3.375
The answer is C. When toric curves are placed on the posterior surface of an RGP lens, 1 1/ 2 times that amount is manifested on the front surface. Therefore, if 3 D is on the back surface, 4.5 D will be on the front surface. This makes the use of a true back surface toric lens rare, since there must be a special relationship between the refractive and corneal cylinder.
142. When toric central posterior curves are placed on the back side of a rigid gas permeable lens of 3 D, how many diopters are manifested on the front surface? A. 2 D B. 3 D C. 4.5 D 0. 6 D
The answer is C. The cross cylinder technique mathematically combines the over-refraction with the lens on the eye to determine the lens power to order. The actual orientation of the lens is of no significance when calculating the final lens power. The fitter should not confuse a cross cylinder with the "LARS" technique and they should utilize either one method or the other to determine final lens power. The final lens will orient in the same position as the initial lens (10 degrees nasally).
143. Utilizing the cross cylinder technique and a computer to determine the resultant power effect in the following situation: Initial right toric lens -3.00 -1.75 cx 180 Over-refraction +0.50 -0.75 cx 120 Resultant effect -2.75 -2.00 cx 90 The lens orients 10 degrees nasally. The lens power to order is: A. -3.00 -1.75 cx 80 B. -2.75 -2.00 cx 80 C. -2.75 -2.00 cx 90 D. -2.75 -2.00 cx 100
The answer is A. The keratometer is a telescope that measures the distance between the reflected mires. The chord length of the reflected distance is translated into a curvature reading. The mires of a steep cornea of 52.00 D will be 2.6 millimeters apart. The chord length of a 52.00 diopter surface is 2.6 millimeters. The mires of a flat cornea of 36.00 diopters will be 3.8 millimeters apart. The chord length of a 36.00 diopter surface is 3.8 millimeters.
144. The keratometer drum reading is 52.00 diopters. The chord diameter of the reflected mires is: A. 2.6 millimeters B. 3.0 millimeters C. 3.4 millimeters 0. 4.8 millimeters
The answer is A. On a patient that has undergone radial keratotomy, the central portion of the cornea is much flatter than it was prior to surgery and may measure flatter than 36.00 D (the normal low end of the keratometer). To extend the keratorneter range, place a -1.00 D over the aperture and estimate the final readings by subtracting 6.00 D from the readings. For example, if the readings obtained with the -1.00 D lens are 41.00 @ 180/ 42.50 @ 90, subtract 6.00 D from each meridian and the result is 35.00@ 180/36.50 @90.
145. Inwhich of the following cases would you expect to need to extend the range of the keratometer from 36.00 to 30.00 D? A. Radial Keratotomy B. Bullous Keratopathy C. Keratoconus D. You cannot extend the range of the keratometer to 30.00 D
The answer is B. Patients with keratoconus will often display very steep keratometer readings that necessitate extending the normal range of the keratometer. By placing a +1.25D lens over the aperture of the keratometer, the range can be extended from 52.00 to 61.00 D. To estimate the new readings, add 9.00 D to the readings. For example, if the readings with the +1.25 D lens in place are 49.00@180/50.00@90, add 9.00 D to each meridian and the result is 58.00@ 180/ 59.00@ 90.
146. Light rays from both distance and near ranges enter the pupil and focus on the retina at the same time. The phenomena is known as: A. Continuous vision B. Translating vision C. Simultaneous vision D. Stereoptic vision
The answer is B. The keratometer (or ophthalmometer) is able to accurately measure only the central 2.6 to 3.8 mm of the cornea. In order to understand more of the corneal topography, an attachment called a topogometer can be used. Photokeratoscopes and corneal mapping systems also allow a more detailed look at the cornea.
147. During the normal use of the keratometer, approximately how much of the central cornea is being measured? A. 1-2 mm B. 3-4 mm C. 5-6 mm D. 7-8 mm
The answer is D. Always begin by transposing the over-refraction into minus cylinder form: -1.50 +1.00 cx 90 becomes -0.50 -1.00 cx 180 Add the spherical portion of the over-refraction to the sphere in the patient's lens: -2.00 + -0.50 = -2.50 Tag on the remaining cylinder and axis to complete the lens parameters: 43.00 -2.50 -1.00 cx 180 9.3
148. A patient in a spherical rigid gas permeable lens complains of poor vision. Patient's lens 43.00 -2.00 9.3 Over-refraction -1.50 +100 cx 90 You have determined lens flexure is not the cause of the cylinder. Which of the following lens designs would represent the new lens parameters? A. 43.00 -3.50 -1.00 cx 180 9.3 B. 43.00 -2.50 -1.00 cx 90 9.3 C. 43.00 -3.50 -1.00 cx 90 9.3 D. 43.00 -2.50 -1.00 cx 180 9.3
The answer is A. The photokeratoscope is an instrument that evaluates the cornea by reflecting concentric rings on its surface. The further apart the rings, the flatter the area being measured. The closer together the rings, the steeper the area being measured.
149. The photokeratoscope is based on the principles of the: A. Placido Disk B. Burton Lamp C. Lensometer D. Radiuscope
The answer is D. Many modifi~ations to rigid gas permeable lenses can be done in the office, saving time and improving service. Blending peripheral curves, adding minus power, adding plus power, polishing the edges, polishing the anterior and posterior surfaces, as well as reducing lens diameter are all examples of modifications that can be performed in the office.
15. Which of the following modifications can be made to a rigid gas permeable lens in the office? A. Blending B. Changing the power C. Polishing the edge D. Changing the base curve
The answer D. The keratometer measures only the central 2.6 to 3.8 mm of the cornea and is limited in the information it can provide about more "unusual" corneas. In radial keratotomy and photorefractive keratectomy, the central cornea has been altered and no longer can be used to define what the peripheral cornea (where the lens actually fits) looks like. In keratoconus, the cornea is very distorted, making it difficult to get useful information from the keratometer.
151. Keratometry is very limited in the detail it provides. In which situation will this prove to be less of a factor? A. Photorefractive keratectomy B. Keratoconus C. Radial keratometry D. Regular astigmatism
The answer is B. Glaucoma is a condition caused by increased intraocular pressure (IOP) and can not be identified or diagnosed by way of the cornea or corneal mapping. However, keratoconus, pellucid marginal degeneration and contact lens induced corneal warpage are all condi- tions affecting the cornea and can be diagnosed in the early stages with the aid of a mapping system.
152. Which of the following cannot be initially interpreted/ diagnosed with the aid of a corneal mapping system? A. Keratoconus B. Glaucoma C. Pellucid Marginal Degeneration D. Contact Lens Induced Corneal Warpage
The answer is A. The power of a lens is equal to the reciprocal of its focal length in meters. A one diopter lens has a reciprocal of one (l / 1 = 1/ 1) therefore, it brings parallel rays of incident light to focus at one meter.
153. A lens having one diopter of power will bring parallel rays of incident light to a focus from the eye at a distance of: A. One meter B. 10 millimeters C. 1000 centimeters D. 1.37 meters
The answer is A. A concave lens (minus lens) may be considered a group of prisms placed apex to apex. The direction of the base will correspond to direction of decentration.
154. An object viewed through a concave lens will have: A. "With" motion B. "Against" motion C. Displacement D. Chromatic aberration
The answer is B. UVB radiation encompasses the range of ultraviolet radiation from 290 to 315 nm. UVC is found in lower wavelengths (100 to 290 nm) and is filtered out by the ozone layer. UVD is not a real part of the ultraviolet wavelength.
155. Which of the ultraviolet wavelengths is responsible for photokeratitis? A. UVA B. UVB C. UVC D. UVD
The answer is D. Full cylinder power is found 90 degrees away from the established cylinder axis. At 30 degrees away from the axis, 25 % of the cylinder power is in effect. At a point located 45 degrees away from the cylinder axis, there is 50 % of the effective power available. Cylinder power 60 degrees away from the axis will show 75% of its power. This is most important to understand when toric lenses are involved. While few toric lenses will orient 30 degrees away from the desired axis, it is an important point to remember that the effective power of the lens changes as the location of the cylinder axis changes.
156. A cylinder power 30 degrees from the axis will show: A. 75% of its power B. 50% of its power C. 30% of its power D. 25% of its power
The answer is A. The contact lens rotates 10 degrees making the effective axis of the lens ordered at 60 degrees actually 70 degrees. Therefore, following the rule of "LARS" (left add, right subtract), you would need to order a lens with axis 50 degrees so that the resultant axis is 60.
157. Consider the following information: Rx -3.00 -1.25ex60 Diagnostic soft toric lens rotates 10 degrees to the right What axis would you consider for the soft toric lens? A. -3.00 -1.25 cx 50 B. -3.00 -1.25 cx 60 C. -3.00 -1.25 cx 70 D. -3.00 -1.00 cx 90
The answer is B. When calculating the power for a bitoric lens, the Rx is first put into minus cylinder (already done in our example). The spherical power (most plus) is put on the flattest meridian of an optical cross, while the total power (combination of sphere and cylinder) is placed on the steepest meridian. Each power must then be vertexed if it is represented by values over+ /- 4.00 D.
158. Calculate the contact lens power for a bitoric rigid gas permeable lens fit on K given the following information: Rx -12.75 -4.75 ex 180 A. -11.12 -4.75 B. -11.12 -14.50 C. -12.75 -4.75 D. -12.75 -17.50
The answer is A. The keratometer' s reflected mires are measured by a calibrated doubling device which is designed to measure a convex surface such as the cornea. The keratometer is a short focus telescope. The distance between reflected mires is measured which results in the chord length of the cornea. The chord length is converted into a dioptric or millimeter measurement of the corneal surface. For example, when measuring a corneal surface of 45.00 D, the plus mires of the keratometer on the corneal surface would be 3 mm apart. This is a 3 mm chord length that the keratometer interprets as a 45.00 D corneal reading.
159. Keratometry measures the radius of curvature of the anterior surface of the cornea on the basis of the cornea's reflective properties as a: A. Convex mirror B. Concave mirror C. Aspheric refractive surface D. Lens doubling device
The answer is A. Sagittal depth is defined as a straight line distance between the back surface of the contact lens at its apex and the chord diameter of the lens.
160. Sagittal depth is defined as the: A. Distance between the crest of the contact lens arc and a straight line connecting the diameter of the lens chord B. Distance between the diameter of an arc and its circumference C. Distance between the crest of the contact lens arc and the circumference of the lens D. Distance between the crest of the arc of a contact lens and the cornea
The answer is C. Sclerotic scatter is the best technique available to view corneal edema. This slit lamp illumination utilizes the naked eye with the beam of the slit lamp at a 90 degree angle to the cornea.
161. When checking the cornea for edema, you should: A. Use the naked eye with indirect illumination B. Use the eye piece with retro-illumination C. Use the naked eye with sclerotic scatter illumination D. Use the naked eye with an optical section
The answer is A. The use of extended wear soft lenses, to date, has been responsible for the greatest number of corneal ulcers in the contact lens wearing population.
162. Which of the following factors puts a patient at greater risk for developing a corneal ulcer? A. Extended wear use B. Daily soft lens use C. Tinted soft lens use D. Rigid gas permeable use
The answer is C. Given the increased risk of ulcerative keratitis among conventional extended wear patients, any patient who sleeps in his lenses and complains of redness and pain should be seen immediately by a professional. Even though it may be a solution reaction or benign condition, it should never be assumed that is the case and the patient should never be put at unnecessary risk.
163. A conventional extended wear patient calls your office and complains of redness and pain. He sleeps in his lenses six night s a week and removes them overnight on the seventh night. He is currently using a multi-purpose care system. What advice would you give him? A. Remove the lenses and do not insert until they feel better B. Remove the lenses daily and change to an oxidative care system C. Come into the office immediately D. Schedule an appointment next week
The answer is A. Bitoric RGPlenses are indicated when both the corneal and refractive cylinder are greater than 2 1/ 2 diopters and are of unequal amounts. In this case, there is too much corneal astigmatism for a front surface toric lens (which has a spherical back surface and a toric front surface) and the against the rule astigmatism would probably result in decentration and rocking of any lens with a spherical posterior surface. A back surface toric lens would not work optically for this patient. While an aspheric lens may work for this patient, the high amount of against the rule cylinder and large amount of refractive astigmatism do not make it the lens of first choice.
165. If a patient has three diopters of against the rule corneal cylinder and 2 1/ 2 diopters of refractive cylinder, the RGP lens design that will give the best vision and comfort is a: A. Bitoric rigid gas permeable lens B. Back surface toric RGP lens C. Front surface toric RGP lens D. Aspheric RGP lens
The answer is C. Striae, ("stretch marks" on the posterior of the cornea); Fleischer's Ring, (iron deposits at the base of a cone); comeal scarring due to rigid lens wear; and corneal thinning are all indications of keratoconus.
165. Striae, Fleischer's ring, corneal thinning and corneal scarring. If you observed the previous signs on a patient during your slit lamp examination, you might conclude that the patient has: A. Corneal edema B. Corneal transplant C. Keratoconus D. None of the above
The answer is D. Diffuse refers to an open beam that gives an overall view of the area, but no fine detail. Direct refers to the light being focused on the area being studied. Other types of slit lamp illuminations are retro-illumination, sclerotic scatter, and indirect.
166. "Diffuse" and "Direct" refer to what? A. Types of SPK B. Personalities of patients C. Soft lens manufacturing D. Types of slit lamp illuminations
The answer is B. Microcysts are a recognized sign of longterm hypoxia. This lack of oxygen causes trapped cellular debris to form within the epithelium.
167. What causes microcysts? A. Chemical reactions B. Lack of oxygen C. Allergies D. Flat fitting lenses
The answer is A. For new contact lens wearers, it is important that they understand the importance of good followup. They should be checked within the first two weeks (sooner if they experience problems) to make certain that they are following the guidelines they have been given and to make sure they are not experiencing any problems.
168. When fitting multifocal contact lenses, over-refractions should be done: A. Monocularly, in normal room lighting B. Binocularly, in low illumination C. Monocularly, in low illumination D. Binocularly, using a phoropter
The answer is D. History taking is a critical part of any evaluation, especially if the patient is currently wearing contact lenses and is new to the practice. Along with the contact lens wearing history, the contact lens professional should question patients regarding their satisfaction with the lenses, what type of lenses they may have previously worn and for how long. They should also obtain a visual acuity, discuss solution use, verify the lens parameters, perform a slit lamp exam and take K readings.
169. Which of the following is a critical part of a patient evaluation for a current contact lens wearer who is new to your practice? A. Contact lens history B. Visual acuity obtained with lens fit C. Patient satisfaction with lenses D. All of the above
The answer is C. The two visual systems utilized by rigid gas permeable bifocals are simultaneous and alternating. With simultaneous vision systems, both near and far images are received by the retina at the same time. Concentric and aspheric bifocal lens designs utilize simulta- neous vision principles. With alternating vision systems, the lens will move on the eye, delivering the focal length that is in front of the pupil as the lens translates . Segmented bifocal lens designs fall into this category.
17. Which of the following are visual systems used by rigid gas permeable bifocal lenses? A. Translating and hyperopic B. Simultaneous and instantaneous C. Simultaneous and alternating D. Truncated and prism ballasted
The answer is C. A Schirmer' s II test is administered using a topical anesthetic and is used to estimate the quantity of tears produced by the patient.
170. A Schirmer's II test will help to determine: A. Tear composition B. Tear chemistry C. Tear production D. Tear capability
The answer is C. Tear break up time is used to determine how long the tear film remains on the surface of the cornea before it breaks apart and dry spots form.
171. A "TBUT" measures: A. Tear composition B. Tear chemistry C. Tear evaporation rate D. Teal'.volume
The answer is C. Wetting and soaking solution is vital for disinfection, surface wettability, maintaining good surface quality and providing better comfort on lens insertion.
172. Which of the following is not a reason to soak rigid gas permeable lenses in a wetting and soaking solution overnight? A. To make the surface more wettable B. To disinfect the surface C. To make the lens more gas permeable D. To help keep the lens from being scratched while in the case
The answer is D. While individual needs and choices may vary, every lens that is re-inserted by a patient must have been cleaned (surfactant cleaner) and stored in a solution that continues the disinfection process (wetting and soaking solution or conditioner). Enzyme cleaners are recommended on a schedule prescribed by the patient's contact lens professional and may not be indicated for all patients.
173. What are the basic components of a rigid gas permeable care system? A. Surfactant cleaner and lubricant B. Enzyme cleaner C. Wetting solution and enzyme D. Surfactant cleaner and wetting and soaking solution
The answer is C. Dimple veil staining is caused by a steep lens to cornea relationship. Air bubbles become trapped under the lens and cause small depressions in the cornea where fluorescein pools. Upon removal of the lens, the depressions disappear. This patient's lens fit should be evaluated and changed.
174. An RGP patient comes in for her first recheck appointment after receiving new lenses. She has no complaints. Upon fluorescein examination, you notice some central round areas of "staining". Upon removal of the lens and re-examination in a few minutes, the "stains" are gone, but depressions are still apparent in the area. After a few more minutes, these depressions are also gone. This patient has exhibited: A. SPK B. Toxic reaction to solutions C. Dimple veil staining D. Corneal abrasion
The answer is C. A bitoric lens has two curves on both the anterior (front) and the posterior (back) surface. This will result in the reading of two base curves in the radiuscope and a sphero-cylindrical reading in the lensometer. A back surface toric lens will also show two base curves in the radiuscope and a sphero-cylindrical reading in the lensometer. A front surface toric will have a spherical base curve, but a sphero-cylindrical lensometer reading. Interestingly, a warped lens will display two base curves in the radiuscope, but a spherical lensometer reading.
176. Verifying a bitoric lens will result in: A. Two base curves in the radiuscope and a spherical reading in the lensometer B. One base curve in the radiuscope and a sphero-cylindrical reading in the lensometer C. Two base curves in the radiuscope and a sphero-cylindrical reading in the lensometer D. One base curve in the radiuscope and a spherical reading in the lensometer
The answer is C. Dk/L represents the oxygen transmissibility of a contact lens material and is the most important factor to consider when evaluating a lens material's appropriateness for extended wear. The greater the Dk/L, the greater the oxygen permeability.
177. RGP materials that are approved by the FDA for extended wear are different from daily wear materials because they have a: A. Greater wetting angle B. Reduced wetting angle C. Greater Dk/L D. Reduced Dk/L
The answer is D. While the incidence of hypersensitivities from multi-purpose care systems is much less than conventional chemical systems, these systems contain preservatives. Hydrogen peroxide systems can perform the disinfection process and decompose into saline and oxygen. Even with a saline rinse that includes a preservative, the presence of preservatives within the lens is reduced because the lens is not soaked in the saline but is simply rinsed with it.
178. A patient wearing soft contact lenses who has developed a hypersensitivity to many preservatives in his care system would have the best chance of success with which of the following methods of disinfection? A. Multi-purpose solution without saline rinse B. Multi-purpose solution with sensitive eye saline rinse C. Chemical care system with non-preserved saline rinse D. Hydrogen peroxide system with sensitive eye saline rinse
The answer is A. The process of cleaning and rinsing is responsible for reducing most of the bacterial load on the surface of the contact lens and is vital to the disinfection process. Without proper cleaning, the disinfection process cannot work effectively.
179. The purpose of using a soft lens surfactant cleaner prior to disinfection is to remove surface deposits from the lens and to: A. Lower the bacteria count to aid in disinfection B. Increase the wetting angle C. Lower the water content D. Decrease the preservative build up on the lens
The answer is D. Most translating or alternating rigid gas permeable bifocal lenses must be stabilized in order for the proper segment to align correctly with the pupil. Two methods of accomplishing this are by truncating and/ or prism ballasting the lens. In truncation, the bottom portion of the lens is removed, producing a straight edge that interacts ·with the lid and aligns the lens in its proper position. With prism ballasting, the bottom portion of the lens is made thicker than the top portion. Following the same principles as prism ballasting of a soft toric lens, the thicker portion of the lens will be forced from under the upper lid to an inferior position.
18. Which of the following are methods for stabilizing the rotation of rigid bifocal contact lenses? A. Back surface toric and front surface toric B. Edge roll and polish C. Alternating and translating D. Truncation and prism ballast
The answer is A. A tear break up time is performed by instilling fluorescein, having the patient blink to spread the fluorescein evenly on the cornea and then viewing the exposed cornea with a slit lamp to determine how long it takes until dry spots form. A tear break up time of at least 10 to 12 seconds is ideal for contact lens wearers.
180. Tear break up time is measured by using what diagnostic tool / device? A. Fluorescein B. Rose Bengal C. Tear film breakup D. Schirmer
The answer is A. Teaching patients to look for these complications can help them seek treatment for a potentially dangerous situation. While vascularization is a complication, it is not something that the patient normally identifies.
181. An infection that may result from swimming, showering, using a hot tub, or rinsing contact lenses with cold water and is often misdiagnosed and treated as herpes simplex is known as: A. Dendritic keratitis B. Superficial punctuate keratitis C. Acanthamoeba keratitis D. Microbial keratitis
The answer is D. All contact lens wearers, soft and rigid gas permeable, should be evaluated with fluores- cein at every follow-up visit. However, with soft lenses, the fluorescein will discolor the soft lens if it is present in the tears when the lens in place. Therefore, either the eye must be thoroughly rinsed before re-inserting the lens or a high molecular weight fluorescein, such as Fluorosoft, should be used. (NOTE: High molecular fluorescein will still discolor FDA Group IV lenses).
182. Which statement is least true when it comes to fluorescein staining in soft lens wearers: A. Should be done at every follow-up visit B. Will cause the soft lens to discolor if it is done with the soft lens in place C. Should be done with Fluorosoft, or a high molecular weight fluorescein D. Is a good idea, but not necessary
The answer is B. A complete professional follow-up should consist of a Subjective verbal communication with the patient (S), critical Objective observation by the contact lens professional (0), educated Assessment (A) and a well defined Plan of action (P). The subjective examination enables patients to describe their symptoms and wearing experiences and help the fitter to develop a course of action for follow-up. The objective exam includes visual acuity, over-refraction, slit lamp examination with lenses in situ and after lens removal, follow-up refraction, follow-up keratometry and lens inspection. Assessment involves collecting all of the data from the subjective and objective examinations and using it to formulate a conclusion. The plan will summarize the patient's needs and serve as a review at the next follow-up visit.
184. When conducting a follow-up contact lens exam, the SOAP method is useful for consistent check-ups . This acronym stands for: A. Selection, Observations, Assessment, Payment B. Subjective exam, Objective exam, Assessment, Plan C. Slit Lamp, Over-refract, Acuity, Performance D. Stain Often And Properly
The answer is A. A new extended wear lens patient should be checked within the first 24 hours of sleeping in the lens. After that, the patient should not need to be checked daily, but should be able to have his follow up schedule slowly lengthened. The patient, however, should always be checked every 3 to 6 months.
185. An appropriate follow-up schedule for either a new soft or rigid gas permeable extended wear lens wearer would be: A. 24 hours, 3 days, 1 week, 1 month, every 3 to 6 months after B. 24hours, 48hours,72hours, 1month, 6months after C. 1 week, 1 month, 6 months after D. 24 hours, 1 month, 6 months, 1 year
The answer is A. There is a prismatic effect from spectacles that occurs when the patient's eyes converge on a near image. When a nearsighted person converges through a concave lens, the prismatic effect of the lens creates base in prism, which moves the image nasally when the patient views near objects. This effect enables the individual to use less accommodation with spectacles than with contact lenses. The opposite effect occurs with farsighted patients, who will require less accommodation with contact lenses than with spectacles.
186. A nearsighted person will feel lack of accommodation from presbyopia: A. Earlier with contact lenses B. Earlier with spectacles C. Simultaneously with contact lenses and spectacles D. Not at all with contact lenses
The answer is D. Overnight wear of lenses has been shown to significantly increase a patient's risk of developing infections or ulcers. Use of homemade saline and / or tap water has also been associated with the acanthamoeba infection and should be discouraged for all contact lens wearers.
188. Which of the following are increased risk factors for the development of corneal infiltrates and ulcers in soft contact lens patients? A. Overnight wear of contact lenses B. Use of homemade saline C. Tap water use D. All of the above
The answer is D. Depending on the severity of the case, a number of actions could be taken. If a reaction to preservatives is suspected, it is important that the preservative be completely eliminated from the patient's care routine. This is best achieved by using a preservative-free care system, such as an oxidative system, replacing the lenses (which may have some of the preservative still within them) or perhaps discontinuing the lenses to allow the cornea to "heal".
189. It is suspected that a patient is suffering from a severe reaction to the preservatives in a chemical care system. Which of these steps would least likely alleviate the problem? A. Change to an oxidative care system B. Discontinue lens wear until symptoms resolve C. Replace the contact lenses D. Prescribe a preservative-free lubricant
The answer is D. Flattening the base curve of the lens and decreasing the overall diameter will each decrease the sagittal depth of the contact lens. By combining both factors, the impact will be magnified. Steepening the base curve and increasing the overall diameter will both increase the sagittal depth.
19. To decrease the sagittal depth of a rigid gas permeable contact lens you can: 1. Steepen the base curve 2. Flatten the base curve 3. Increasetheoveralldiameter 4. Decrease the overall diameter A. 1and4 B. 1and3 C. 2and3 D. 2and4
The answer is C. The presence of an infiltrate is a serious matter and the patient should be referred to an ophthalmologist for diagnosis and treatment.
190. Infiltrates should be treated by: A. Patching the patient B. Topical antibiotics C. Referring the patient to a doctor D. Refitting to a lens with higher Dk
The answer is C. Benzylkonium Chloride (BAK) has been known to cause serious complications when used in conjunction with soft contact lenses and is not used in soft lens solutions, since it can build up in high concentrations in the lens matrix and cause a toxic keratitis.
191. Which preservative, found in rigid gas permeable solutions, can cause serious problems for users of soft contact lenses? A. Dymed B. Chlorhexidine C. Thimerosal D. None of the above
The answer is D. Bandage lenses are very useful and can be the source of great relief for patients whose corneas are compromised. The eyelid blinks across the corneal surface an average of 17,000 times a day and for a patient with an irritated cornea this can be extremely painful. In cases of recurrent erosion, bullous keratopathy and post photorefractive keratectomy, as well as numerous other conditions, the lens provides a respite from the mechanical action and trauma of the eyelids.
192. In which of the following situations may a bandage lens be required? A. Recurrent Erosion B. Bullous keratopathy C. Photorefractive Keratectomy D. Keratoconus
The answer is A. Water and soft contact lenses can be a bad combination. The bacteria, fungi, amoebae and other organisms crawling around in the water are not welcome additions to a contact lens system. The only safe measures are to keep the lenses away from the water (water tight goggles can provide that) or to throw them away immediately upon coming out of the water.
193. In which situation is it safe for disposable soft lens patients to wear lenses while swimming? A. If they throw them away afterwards B. If they throw them away in a few days C. If they keep their eyes closed D. If they use a preservative-free lubricant afterwards
The answer is A. Patients with rheumatoid arthritis have been known to present with very dry eyes, which can preclude contact lens wearing success. Loss of lid elasticity and light sensitivity could also make contact lens wearing more difficult, however, these symptoms are not typically associated with rheumatoid arthritis. Poor vision without correction is usually an indication for contact lenses, not a contraindication.
194. Which of the following reasons could make it difficult for a rheumatoid arthritis patient to wear contact lenses? A. Dry eyes B. Loss of lid elasticity C. Poor vision D. Light sensitivity
The answer is A. The radial folds of epithelial cells at the limbus (Palisades of Vogt) and increased surface area of basal cells, are well suited for increased mitosis and epithelial repair. Therefore, limbal epithelial hypertrophy can clear in three to five days.
195. Soft lens induced limbal epithelial hypertrophy usually clears in: A. 3 to 5days B. 1 month C. 2 months D. 3 months
The answer is A. Following photorefractive keratotomy, the laser burns through Bowman's membrane into the stroma where the refractive changes occur from sculpting of the stromal tissue. The optical changes are geometric changes and do not affect the index of refraction. The epithelium fully regenerates, but the cornea is left without Bowman's membrane.
196. Following PRK: A. Bowman's membrane does not regenerate B. The epithelium does not return C. All corneal cell layers regenerate D. The index of refraction of the cornea is altered
The answer is C. Reducing the water content and increasing the thickness of the lens will aid in reducing problems with dehydration. The more mass there is to the lens, the less chance of dehydration.
197. If a soft lens patient is having dehydration problems with a thin 55% water content lens, the best lens to use to minimize the problem is: A. 38.5% water content thin lens B. 70% water content thin lens C. 38.5% water content thick lens D. 70% water content thick lens
The answer is C. The average pH of the human tear is 7.45, so saline solution manufacturers strive to mirror that pH as closely as possible to prevent stinging on insertion.
198. Saline solutions are normally buffered to a pH of: A. 6.4 B. 6.9 C. 7.4 D. 8.3
The answer is B. A lens that is too tight is more likely to be well tolerated by the patient at the beginning of the day, but comfort drops off significantly as the lens becomes tighter. Loose lenses are typically irritating at the beginning of the day and solutions are most irritating when the lenses are first inserted.
199. Which of the following will be more likely to bother a patient at the end of the wearing time rather than at the beginning? A. A loose lens B. A tight lens C. Solutions D. None of the above
The answer is B. Dimple veil staining is not traditional staining but is rather a pooling of fluorescein in depressions or "dimples" on the surface of the cornea. These dimples are caused by air bubbles that become trapped behind a rigid lens in an area where the distance between the lens and cornea is too great. Dimples will be found centrally if the base curve is too steep and peripherally if the base curve or peripheral curves are too flat.
20. Dimple veil staining on the cornea is caused by: A. Poor polishing of peripheral curves B. Air bubbles trapped under a rigid lens C. Debris trapped under a rigid lens D. A cracked contact lens
The answer is B. Small, steep lens designs for keratoconus often present a challenge for proper cleaning. A Q tip, saturated with the patient's daily cleaner, is better able to reach that steep inside surface. Dish soap is not an approved RGP cleaner and should not be recommended to the patients. Cleaning the lenses in the morning will not improve the cleaning of the inside surface and is not recommended since the bacterial load will be increased. Although reducing wearing time will often reduce deposits on the lens, it is not a feasible alternative for most keratoconus patients.
200. A non-ulcerative sterile keratitis condition that is often associated with overnight contact lens wear and colonization of Gram-negative bacteria on the contact lens surface known as: A. Giant papillary conjunctivitis B. Limbal hyperemia C. Contact lens associated red eye D. Acanthamoeba keratitis
The answer is A. If your practice receives a referral for a new patient, it is considered appropriate to send them a letter to thank them. This formal thank you can then become a part of the patient's record in both the ophthalmologist and your offices.
201. A patient is referred into your office for a contact lens fitting by a neighboring ophthal- mologist. Upon initial evaluation and fitting of the contact lenses, it is appropriate to: A. Send a letter of thanks to the referring ophthalmologist B. Buy the referring ophthalmologist lunch or dinner C. Call the referring ophthalmologist and thank him or her for the referral D. Send a gift to the referring ophthalmologist
The answer is B. Retention of office staff plays an important role in a successful practice. The more experienced the staff is, the less valu_able time needs to be spent on training and orientation. It can also help to make patients feel more comfortable when they are able to see the same faces in an office from visit to visit. Staff recognition awards, increased benefits and flexible hours are all perks that can encourage the retention of valuable staff members.
204. Which of the following is not an effective way to enhance staff retention? A. Staff recognition awards B. Decrease in pension plans C. Increased benefits D. Flexible hours
The answer is D. Sexual harassment in the workplace constitutes a serious situation. Sexual harassment is unwelcome sexual advances, requests for sexual favors and other verbal or physical conduct of a sexual nature. It also occurs when looks, teasing, jokes, pictures, or magazines make someone uncomfortable in the workplace or when job security or promotion is tied to sexual conduct, either real or implied. Men as well as women can be either the victim or the perpetrator of sexual harassment.
205. Sexual harassment occurs: A. When looks, teasing, jokes, or pictures make someone uncomfortable in the workplace B. When job security or promotion is tied to sexual conduct, either real or implied C. Against men as well as women D. All of the above
The answer is D. Documentation in a patient's chart should not be taken lightly. The information found there is considered an important part of their medical history. The information can also be used in a legal setting in the event of court proceedings. But most importantly, the information within the document is considered confidential and should be treated with the utmost respect.
206. The patient's chart is not: A. A medical history B. A legal document C. Confidential D. Public information under the freedom of information act
The answer is D. Money can often be the source of hurt feelings and confusion between well-meaning practitioners and their patients. In order to avoid confusion when a refund is expected, have the policy in writing and explain it to the patient before they agree to the contact lens fitting. It is also helpful to have a carbonless document that spells out the refund policy that the patient can sign. One copy can go into their charts and the other can be sent home with the patient to reduce confusion.
208. To reduce any confusion regarding refund policies, they should be: A. Put in writing B. Signed by the patient C. Explained at the fitting D. They should only be explaining by the fitter
The answer is C. It is sometimes difficult for patients to grasp the concept of the ocular structures and their role in vision. Pamphlets, diagrams, charts and sketches are great tools to employ when educating the patient. It can also help to have them visualize common objects that they are familiar with in order to give them a better understanding of the concepts you are trying to teach. To explain significant amounts of corneal astigmatism, a football gives the patient a good visual aid. A baseball can be used to describe a cornea with little to no astigmatism and a watch crystal can be used to explain the placement of the cornea in respect to the other elements of the eye.
209. To explain a cornea with significant astigmatism to the patient you can have them envision: A. A baseball B. A mirror C. A football D. A watch crystal
The answer is B. The parameters listed in C and D will flatten the lens to cornea relationship. While answer A does steepen the lens' relationship, it does not take into account the change in the power that is necessary when the base curve of the lens is altered.
21. The GP multifocal design that relies on the use of a variable rate of curvature across the lens surface to achieve a change in power is known as: A. Concentric B. Translating C. Aspheric D. Truncated
The answer is B. Clear office policies should allow immediate identification of the provider of care. Also, policies regarding individual calibration of instruments and identification of the source of data should be determined to assure accountability and reproducibility.
210. Upon follow up examination you find that the keratometric readings for the patient have changed by 0.75D. After reviewing the original chart, you cannot determine who took the patient 's original K readings. It can also not be determined if the readings were taken with a manual keratometer, automated keratometer or computerized corneal mapping instrument. Which of the following is a true statement? A. Keratometric readings are used for original fittings and are not a factor in this case B. Office policies should be developed so that the technician and method of instrumentation can be easily identified in each patient's chart C. It is not necessary to know "who" actually took the original keratometric readings D. Various instruments measure keratometric surfaces the same and the type of instrument used is not a factor
The answer is D. All decisions made regarding the hiring, firing, promotion or salary of an employee must be made only with regards to their individual ability to perform their jobs. Factors such as race, religion, age, marital status, national origin or sex, cannot be considered regarding employment issues.
211. Which of the following can you consider in the employment, promotion, salary review or termination of an employee? A. Race B. Marital status C. Age D. Employee performance
The answer is A. Dimple veil "staining" occurs when there are bubbles trapped beneath a rigid contact lens. The bubbles produce dimples or indentations on the cornea that fill with fluorescein and are obvious during a slit lamp exam. They do not constitute an ocular emergency and can be remedied by removing the lens and refitting the patient. However, all of the other situations listed do pose an ocular emergency and these patients should be referred on to an ophthalmologist or other medical professional.
212. Which of the following is not a critical ocular emergency that requires immediate referral to an eye doctor? A. Dimple veil staining B. A chemical burn C. Sudden loss of vision D. A penetrating injury
The answer is C. Whenever a patient complains of redness, pain or a significant decrease in vision, they should be instructed to remove the contact lens immediately. Their next step should be to call the practitioner to discuss more fully the symptoms and possible resolution of them.
213. A patient has recently been dispensed soft lenses for the first time. They call the office and complain of pain, redness, and light sensitivity. They should be instructed to: A. Check to make certain the lens is not inside out B. Flush the eye with sterile saline C. Remove the contact lens D. Change their care system
The answer is C. While many practices have grown used to running behind schedule and many feel this is unavoidable, when it happ_ens consistently, it should be investigated and determined whether better time management can alleviate the situation. While you may feel lucky to be busy, the patients will often grow weary of the consistent undervaluing of their time. The other options listed may make the wait less tiresome, but will only put a bandage on the problem that exists.
214. You have noticed that your practice consistently runs 60-80 minutes behind schedule every day. While the staff has grown used to it, the patients have begun to complain. What should you do? A. Run continuous loop videos in the waiting room for entertainment B. Offer coffee or snacks for those patients who have been waiting long C. Re-evaluate your schedule to make it run more efficiently to reduce waiting time for the patients D. Start earlier in the morning and work through lunch
The answer is D. There should never be an assumption of usage with contact lens products. Contact lenses are prescription items that have specific guidelines set forth by the FDA. Specific directions to the patient regarding product usage should be documented in the patient record with the dispenser identified by initials or signature. Instructions for lenses and solutions should be dispensed to all patients.
215. A new patient is fit with disposable soft lenses. The lenses are approved by the FDA for either one week extended wear use or two week daily wear use. Office documentation clearly identifies all pre-fit measurements along with the final lens type. The patient appears extremely confident with the lenses and written instructions are not referred to or dispensed with the lenses. Which of the following is a true statement? A. Pre-fit measurements, along with the lens type, provides adequate patient documentation B. Written care instructions are not required for extremely confident patients C. The patient should feel free to wear the lenses as daily or extended wear due to the FDA approval of the lens product D. Office documentation should clearly indicate the wear modality (daily or extended wear), the frequency of replacement and all provided solutions along with care instructions.
The answer is D. Contact lens professionals have a duty to warn all patients of potential complications. If a recommended product has a higher frequency of complications, the fitter has a professional, ethical and legal obligation to notify the patient regardless of personal biases. If the patient is aware of such a situation, it is wise to have an office policy requiring the patient to sign a document indicating such knowledge.
216. You and your office are proactive with extended wear products and the majority of your patients are utilizing extended wear lenses. You feel that the current patient is an ideal extended wear patient. During pre-fit evaluation, your discussion with the patient should include: A. Only the positive aspects of extended wear products B. How extended wear is superior over all other options C. The various extended wear options leaving out the time consuming alternative options D. The increased occurrence of infectious keratitis with extended wear when compared to daily wear
The answer is A. To determine the average chair costs for your practice, which is the amount of operating expenses per patient, you would divide the cost of operating your practice by the number of patients you see. Net earnings divided by the number of patients would result in the net earnings per patient. Net earnings divided by net sales would result in the net return on sales. The net sales divided by the number of patients results in the gross per patient.
218. To determine your average chair costs, you would use which of the following equations: A. Operating expense / Number of patients B. Net earnings / Number of patients C. Net earnings / Net sales D. Net sales / Number of patients
The answer is A. The dating or shelf life of contact lens solutions are determined by the solution manufacturer and the FDA. Solutions are a regulated product and should be discarded when beyond the designated date. Proper office procedures should be to direct the patient to discard the solution and purchase a new, unexpired bottle.
219. A patient calls indicating that they had bought a large quantity of disinfecting solutions while it was on sale. The expiration date on the bottle now indicates that the solution is out of date by two months. The solution has never been open. You should tell your patient: A. To throw the solution away and purchase new solution B. Use the solution since two months does not really constitute expired solutions C. The date is simply an inventory identification control item. Because the solution has never been opened, it is okay to use D. Because the solution has preservatives in it, it is okay to use
The answer is B. "Dk/L" stands for the oxygen transmissibility of a specific lens when manufactured with a given center thickness. "Dk" stands for the oxygen permeability of the material, but the actual transmission of oxygen thr ough this material is also dependent on the thickness of the lens. While the concept of permeability is important to understand, the real impact is found in the transmissibility of the lens. Wetting angle relates to the ability of tears to spread on the plastic, specific gravity relates to the weight of the lens material and neither are related to corneal oxygenation.
22. To allow for proper corneal oxygenation when fitting rigid gas permeable lenses, which of the following material characteristics must be considered? A. Dk B. Dk/t C. Wetting angle D. Specific gravity
The answer is D. Marketing your practice can take many forms. The key to successful marketing is to determine what works best for your individual practice, geographic area and financial capacity. Even those practices that are limited in funds can successfully market themselves by taking care of their greatest asset-their current patients. Word of mouth is still a strong marketing tool and how you treat your current patients can be the difference between a successful and a failing practice.
220. The training method that involves training a staff member in many facets of a business in addition to their own position is known as: A. Apprenticeship B. Cross training C. Certification D. The 360 degree method
The answer is C. To determine the parameters of a bitoric rigid lens, place the most plus (least minus) power on the flattest meridian (-2.00 Don the 42.00 D meridian) and the most minus (least plus) on the steepest meridian (-2.00 D plus an additional -5 .00 D, for a total of -7.00 Don the 45.25 D meridian). The -7.00 D must be vertexed, which results in -6.50 D. Since we are fitting the lens "on K", the final lens parameters are 42.00 / 45.25 -2.00/-6.50.
23. Given the following information: K's 42.00@180/45.25@90 Rx -2.00 -5.00 cx 180 Which of the following specifications, given in actual drum readings, would represent a bitoric lens fit "on K"? A. 42.00/45.25 -2.00 /-3.00 B. 42.00/45.25 -2.00 /-5.00 C. 42.00/45.25 -2.00 /-6.50 D. 42.00/45.25 -2.00 /-9.00
The answer is A. The only listed set of specifications that will give the patient a good visual result is answer A. In this case, the lens is fit 0.50 D flat in the horizontal meridian and is 0.50 D flat in the vertical meridian. To determine the lens power, work with the patient's refraction in minus cylinder and apply the principles of "SAM/FAP" (Steep Add Minus, Flat Add Plus) to the sphere power only. In this case, the flattest meridian was fit 0.50 D flatter, creating 0.50 D of minus power. To compensate for this, 0.50 D of plus must be added to the -1.00D of sphere power in the patient's Rx, resulting in -0.50D. The 3.000 of refractive cylinder is corrected by the 2.00 D of cylinder on the posterior surface of the lens. Back surface toric lenses will correct refractive cylinder that is 1 1/ 2 times the amount of cylinder on its back surface. While all back surface toric lenses do not need to be fit 0.50 D flatter than Kin both principal meridians, none of the other options listed will result in an appropriate lens prescription .
24. Given the following patient information: K's 41.25@180 / 43.25@90 Rx -1.00 -3.00 cx 180 The best parameters for a back surface toric rigid gas permeable lens would be: A. 40.75/42.75 -0.50 B. 40.75/43.25 -1.00 C. 41.25/43.25 -4.00 D. 41.25/44.25 -1.00
25. The answer is D. A front surface toric lens will show clear mires in all meridians which indicates a spherical posterior surface. Warped, bitoric and back surface toric lenses will all show unclear mires in the radiuscope indicating that the posterior surface is not spherical. In the lensometer, bitoric, back toric and front surface toric lenses will all display sphero-cylindrical readings. Only the warped lens will show a spherical lensometer reading.
25. When verifying the posterior curves of a rigid gas permeable not all of the mires are clear in all meridians. This can occur in all but a: A. Warped lens B. Bitoric lens C. Back surface toric lens D. Front surface toric lens
The answer is D. VLK, or Vascularized Limbal Keratitis, is a condition associated with rigid gas permeable lenses, predominantly those lenses that are designed with low edge lifts and large diameters. In its most advanced stage, a heaping of the corneal epithelium in the area of irritation becomes evident. This area becomes vascularized from the conjunctiva to the limbus leading to the elevated mass in the area. Staining on the cornea and conjunctiva accompany patient symptoms which may include reduced wearing time, redness, photophobia and in some instances, pain.
26. Heaping of epithelium, vascularization, and staining of the conjunctiva and cornea are characteristic of... A. Corneal warpage B. Gian papillary C. Vascularized limbal keratitis D. Dendritic keratitis
The answer is B. Dimple veil staining may occur when there is either a steeper or flatter than recommended lens to cornea relationship. Air bubbles become trapped in the excessive space and create dimples on the corneal surface. Antibiotics will not affect dimple veil staining, nor will lenticulating the edges. Re-evaluating the lens to cornea relationship will identify the problem and allow the fitter to change the base curve and/ or peripheral curves to eliminate the dimples.
29. Dimple veil staining is resolved by: 1. Antibiotics 2. Steepening the lens to cornea relationship 3. Flattening the lens to cornea relationship 4. Lenticulation A. 1 and 2 are correct B. 2 and 3 are correct C. 1, 2 and 4 are correct D. None of the above will resolve dimple veil staining
The term-28answer is A. An uncut rigid gas permeable lens has both the posterior and anterior surface cut and polished. It does not have a peripheral curve system, or a final diameter. The subsequent steps in lens fabrication would be to reduce the lens to within a 1/ 10 of a millimeter of its projected finished diameter, apply the posterior peripheral curves, bevel the front edge and round and taper the edges.
31. An uncut rigid gas permeable contact lens will have the following: A. Both sides surfaced B. One side surfaced C. Semi-finished blank D. One side molded
The answer is C. VascularizedUmbal Keratitis (VLK)is believed to be caused mainly by large diameter rigid gas permeable lenses with low edge lifts. These lenses chafe the epithelium in the limbal area in the three and nine o' dock areas, The tear film in the area may also be altered by this traumatic mechanical effect and has a synergistic effect in causing the vasogenic response known as VLK.
32. Vascularized Limbal Keratitis is usually caused by: A. Dry eye syndrome B. Allergic reaction to solutions C. Mechanical irritation D. Excessive exposure to ultraviolet radiation
The answer is A. When comparing wetting angles, the greater the angle, the less hydrophilic is the lens material. A drop of fluid that creates a 90 degree angle between the drop and the surface is considered an indication of a hydrophobic surface. When there is an angle of 0, the material is considered completely wet. The smallest wetting angle represents the most wettable surface, which is most desirable in RGP materials.
33. When comparing wetting angles, which of the following would be the most desirable? A. 10 B. 20 C. 30 D. 60
The answer is B. A drop of fluid that creates an angle of 90 degrees or greater is considered an indication of a hydrophobic or non-wetting surface. A drop of fluid that creates an angle of 0 to 90 degrees indicates a more wettable material with the lowest values representing the most wettable surfaces. A drop of fluid that creates an angle of O indicates that the material is totally hydrophilic.
34. The greater the ability of a rigid gas permeable lens to wet, the ____ the wetting angle? A. Higher B. Lower C. Deeper D. Rounder
The answer is A. Imagine a contact lens as a portion of a sphere. Assuming that the diameter of a lens is kept constant, if the base curve of a lens is steepened, the distance from the lens periphery to the imaginary center of the sphere will be shorter. (See diagram) The base curve of a lens is expressed by the length of its radius. The shorter the radius, the steeper the curve, conversely the longer radius, the flatter the base curve. Therefore, when the posterior radius of curvature is decreased, the base curve of the rigid gas permeable lens is made steeper. Diameter is constant in each lens, 14mm. The shorter the radius the steeper the lens.
36. When the base curve of a rigid gas permeable lens is said to be made steeper, it means that the posterior radius of curvature is: A. Decreased B. Divided C. Increased D. Elongated
The answer is B. Decreasing edge thickness will allow the lid to re-wet the affected area in the corneal periphery. A base curve cannot be steepened nor can the diameter of a lens be increased, either in the lab or in the office and a new lens would have to be ordered if these changes were required. A diameter gauge is a measuring instrument, not a modification tool.
37. What in-office modification can be performed to alleviate three and nine o'clock staining? A. Steepen the base curve with a conical tool B. Decrease edge thickness with a conical tool C. Flatten the base curve with a conical tool D. Increase the diameter with a diameter gauge
The answer is C. Lens flexure usually occurs when the center of the lens is not thick enough to counteract the force of the lids on a blink. This may occur when there is a great deal of corneal cylinder and the lid forces the lens to flex over a highly astigmatic surface. It may also occur when the lens is inherently thin in the center such as in a high minus lens. Increas- ing the center thickness of the lens will reduce the impact of the lids and will keep the lens from flexing on the eye. Historically, decreasing the Dk of the material will also reduce the ability of the lens material to flex and choosing a lens with a lower Dk is an advantage when attempting to control lens flexure. The closer the lens is to the surface of the cornea, the less it will flex, so fitting the lens in an alignment fitting philosophy will be to the fitter's advantage.
39. What situation will most likely result in lens flexure? A. High plus Rx, low dk B. High plus Rx, high dk C. High minus Rx, high dk D. High minus Rx, low dk
The answer is C. Due to the irregular surface that often results from this vascular growth, the patient's best chance of optimum vision will come with a rigid gas permeable lens. A smaller diameter lens will also have less chance of irritating the pterygium than a larger diameter lens.
40. When fitting a patient with a pterygium that impinges on the cornea by 2 mm at the 9 o'clock area, which of the following designs should be considered.first? A. Soft contact lens B. 9.8 mm diameter RGP lens C. 8.8 mm diameter RGP lens D. Prism ballasted soft lens
The answer is A. Just as the thickness of a rigid gas permeable lens will affect its transmissbility, the thickness of a soft lens will have the same effect. A thicker lens of the same material or thicker parts of a lens (i.e. prism) will be less permeable to oxygen.
41. When fitting an alternating design RGP multifocal lens, the primary function of a truncation is to: A. Center the lens better B. Make the lens more comfortable C. Allow the lens to translate more efficiently D. Lower the bifocal segment
The answer is A. Three point touch refers to the relationship of the soft lens to the cornea. The lens should make contact centrally with the corneal apex, vault the limbus, and have its edges rest on the sclera. Ultra-thin soft lenses, due to their flexure, may drape the cornea completely. A soft lens should never be fit with apical clearance, as this will result in fluctuating vision and seal off in the periphery, resulting in a tight fit.
43. Soft lens fitting should result in: A. Three point touch B. Apical clearance C. Upper lid attachment D. None of the above
The answer is D. The general rule of thumb in choosing a soft lens diameter is that it should be at least 2.0 mm larger than the HVID. If the HVID is 11.0mm, the smallest soft lens diameter should be 13.0 mm.
44. If the HVID (Horizontal Visible Iris Diameter) is 11.0mm, the minimum diameter soft lens you should choose is: A. 14.5 mm B. 14.3 mm C. 14.0 mm D. 13.0 mm
The answer is B. The overall lens diameter and the curve of the posterior portion of the lens determine the sagittal depth of any contact lens, soft or rigid. The larger the diameter and/ or the steeper the base curve, the greater the sagittal depth. Conversely, the smaller the diam- eter and/ or the flatter the base curve, the smaller the sagittal depth.
45. The sagittal depth of a soft lens is determined by: A. Diameter and power B. Base curve and diameter C. Diameter and water content D. Base curve and thickness
The answer is C. Decreasing the lens diameter and flattening the base curve will only serve to loosen this already flat lens. Increasing the center thickness may also loosen the lens fit, as it de- creases capillary attraction and results in greater lens movement.
46. A soft lens displays inferior edge lift on the eye. What can be done to remedy this situation? A. Decrease lens diameter B. Flatten base curve C. Steepen base curve D. Increase center thickness
The answer is B. The most reliable method of assessing the fit of a soft lens is to put your thumb on the lower lid, have the patient look up slightly and push the lens up. If the lens moves freely without much force and then moves gently back into place, it is considered a good fit. Asking the patient how the lens feels should not be a criterion for final evaluation, as patients will usually choose lenses that are initially tight. Fluorescein evaluation will not provide information about the fit of a soft lens and may be absorbed by the lens, causing discoloration.
48. The most effective method of assessing the fit of a soft contact lens is: A. Asking the patient how it feels B. Push up test C. Fluorescein evaluation D. Slit lamp observation with optic section
The answer is B. The larger the diameter, the greater the sagittal depth if the base curve is kept the same. The 14.5 diameters have a greater sagittal depth than their 14.0 counterparts. The steeper the base curve, the greater the sagittal depth. That would mean that the 8.4 would result in a greater sagittal depth than the 8.8 indicating that the 8.4/14.5 lens would have the greatest sagittal depth.
49. If all of the following soft lenses are made with the same design and material, which should have the greatest sagittal depth? A. 8.4/14.0 B. 8.4/14.5 C. 8.8/14.0 D. 8.8/14.5
The.answer is A. The patient's Rx needs to first be transposed to minus cylinder form: -2.00 -1.00 ex 80 When evaluating the rotation of a soft toric lens, the placement of the axis markings on the lens will allow the contact lens professional to determine how much and in what direction to compensate for axis rotation. If the lens rotates to the fitter's left the amount of rotation is added to the axis of the patient's spectacle Rx. If the lens rotates to the fitter's right, the amount of rotation is subtracted from the axis of the patient's spectacle Rx. In the example given, the lens rotated 15 degrees to the right, which means 15 degrees is subtracted from the patient's cylinder axis: 80 -15 =65
51. Given the following information: Diagnostic Lens -2.00 -1.00 cx 90 Patient's Rx -3.00 +1.00 cx 170 The diagnostic lens rotates 15 degrees to the right. What soft toric lens power would you order for this patient? A. -2.00 -1.00 cx 65 B. -2.00 -1.00 cx 75 C. -2.00 -1.00 cx 105 D. -2.00 -1.00 cx 155
The answer is B. HVID stands for Horizontal Visible Iris Diameter and is determined by measuring the iris horizontally at its widest part. An average HVID is 11.5 mm.
52. Initial selection of a soft lens diameter is decided by measuring the HVID. What does this stand for? A. Highest Visible Initial Diameter B. Horizontal Visible Iris Diameter C. Hydrogel Viewing Interstromal Device D. Horizontal VerticalIris Diameter
The answer is A. Cast molding of a soft contact lens results in very consistent lens parameters which allows manufacturers to produce the vast quantities of lenses needed to satisfy the disposable lens market. Lathe cutting is a more costly and labor-intensive method of manufacturing soft lenses and is used for conventional lenses. Spin casting causes the posterior surface of the lens to change as the power increases and results in an aspheric design and a less predictable fit.
53. The manufacturing process most often used for disposable contact lenses is: A. Cast molding B. Lathe cut C. Spin cast D. Wax molding
54. The answer is B. Soft toric lenses are generally made with cylinders of 0.75 D and greater. While not all patients with only 0.75 D of cylinder will require a soft toric lens, this should be a starting point for discussion and evaluation of the need for a soft toric lens to provide the best visi_onfor the patient.
54. What is the least amount of cylinder a patient should have before soft toric lenses are discussed? A. 0.25 D B. 0.75 D C. 1.25 D D. 2.00 D
The answer is A. Discharge, itching and lens displacement in a long time soft lens wearer are classic symptoms of GPC (Giant Papillary Conjunctivitis). Everting the upper lid and looking for enlarged papillae and injection will help the practitioner make the positive diagnosis.
55. When a longterm soft lens wearer complains of discharge, itching, and an occasional pulling up of the lens by the upper lid, the practitioner should: A. Evert the upper lid and check for GPC B. Remove the lens and check for follicles C. Raise the upper lid and check for SLK D. Pull the lower lid down and check for jelly bumps
The answer is C. Soft toric lens manufacturers generally begin with cylinder powers at 0.75 D. Cylinder power requirements less than that are usually not corrected with a toric lens design. While custom soft toric lenses can correct 4.00 D and more of refractive cylinder, the standard range is usually Jess than 3.00 D.
56. What is the average cylinder power range of standard toric soft lenses? A. 0.25 to 1.50 D B. 0.25 to 2.50 D C. 0.75 to 2.50 D D. 0.75 to 4.00 D
The answer is A. The FDA Classifications for soft lens materials are grouped by the water content of the material (low water versus high water) and the electrical charge on their surface (ionic versus non-ionic). Contact lens materials that carry an electrostatic charge are ionic and lens materials that do not carry an electrostatic charge are classified as non-ionic. The neutrally charged lens materials (i.e. non-ionic) are less likely to attract the positively charged proteins and lipids in the tear film. Soft Jens materials that are classified as low water, non-ionic are considered the most deposit resistant materials.
57. Which of the following soft lens material groups is considered the most resistant to deposit formation? A. Low water, non-ionic B. High water, non-ionic C. Low water, ionic D. High water, ionic
The answer is D. The lens material group that is considered the least resistant to deposit formation is the high water, ionic (negatively charged lens surface) lens material. It is also the lens material that is most reactive to solutions and their preservatives.
58. Which of the following soft lens material groups is considered the least resistant to deposit formation? A. Low water, non-ionic B. High water, non-ionic C. Low water, ionic D. High water, ionic
The answer is D. Daily disposable lenses or single use lenses are approved to be worn for only one day and then thrown away. They have not been approved to be used with solutions, nor should they need to be, as they must be discarded after one use.
59. The approved protocol for single use lenses is: A. Clean and disinfect daily B. Clean and disinfect weekly C. Clean and disinfect bi-weekly D. Discard upon lens removal
The answer is C. One would rarely polish or attempt to manipulate the central posterior surface of a rigid lens. Applying polishing pressure to the mid-peripheral and the peripheral anterior surface would add plus power. Applying polishing pressure to the central anterior surface would add minus power.
6. To add minus power to a rigid contact lens with a rotating modifying spindle, one would: A. Polish the posterior surface of the rigid lens B. Polish the mid peripheral anterior surface C. Polish the central anterior surface D. Polish the peripheral anterior surface
The answer is A. The FDA has approved the use of extended wear disposable lenses for no longer than 1 week (6 nights/7 days). Disposable lenses that are worn on a daily wear basis should be replaced after two weeks of daily wear.
60. What is the FDA recommended replacement schedule for disposable lenses that are worn on an extended wear basis? A. 1 week B. 3 months C. 2 weeks D. 1 month
The answer is A. The tonicity of the water in which soft contact lenses are exposed will greatly affect their behavior. For instance, in cases where the soft lens is exposed to a hypotonic solution (i.e. freshwater lakes) the lens diameter will increase and the lens will fit tighter on the eye. In cases where the soft lens is exposed to a hypertonic solution (i.e. salt water}, the lens will fit looser on the eye.
61. Most soft lenses today have a handling tint. The amount of light absorbed by these lenses is: A. 20-30% B. 10-20% C. Less than 10% D. 30-40%
The answer is A. When a soft lens becomes too tight at the edge, it will squeeze down in the periphery and cause limbal compression. Removing the soft lens will often show an indentation ring caused by the edge of the lens. While edema and neovascularization may result from longterm wear of a tight soft lens, they are not the condition that was described. In- creased IOP (intraocular pressure} occurs inside the anterior chamber and is not affected by a tight soft lens.
62. A soft lens is too tight and causes pressure on the sclera at the periphery of the lens edge. This is known as: A. Limbal compression B. Neovascularization C. Edema D. Increased IOP
The answer is B. The keratometer, normally used for measuring the central curve of the cornea, can help to determine if a soft lens is too tight. If the mires clear after the blink and then blur, the lens is too steep or tight. If the mires are clear and then blur after the blink, the lens is too flat or loose. The mires of a well fitting soft lens will remain clear at all times.
63. Which measuring device could help determine if a soft lens is too steep? A. Profile analyzer B. Keratometer C. Ophthalmoscope D. Radiuscope
The answer is A. An average Dk for soft lens materials that contain less than 55% water are in the 8 to 16 range. For soft lens materials that have a greater water content, the average Dk for the material is 20 to 38.
64. What is the approximate clinical measurement of oxygen permeability through a 38 % water content hydrogel lens? A. 9 +/- B. 20 +/- C. 38 +/- D. 55 +/-
The answer is B. Extended wear soft contact lenses are available in a wide range of water contents. Increasing water content is only one method of increasing the oxygen transmission of the lens. Another means of increasing oxygen is making the lens thinner.
65. Extended wear soft contact lenses come in what water contents? A 38% to 55% B. 24% to 79% C. 55% and above D. 71% to 79%
The answer is D. When evaluating the alignment of a diagnostic soft toric lens, the calculations for the new lens are always made in respect to the patient's spectacle prescription, not the diagnostic lens. If the lens rotates to the observer's left, add the amount of rotation to the patient's spectacle axis. If it rotates to the right, subtract the amount of rotation from the axis of the spectacle axis.
66. Given the following information: Rx -3.50 -1.50 ex 170 Diagnostic lens 8.8 -3.50 -1.50 cx 180 Upon initial evaluation, the lens rotates 10 degrees to the observer's left. The lens or- dered should be: A. 8.8 -3.50 -1.50 cx 10 B. 8.8 -3.50 -1.50 cx 160 C. 8.8 -3.50 -1.50 cx 170 D. 8.8 -3.50 -1.50 cx 180
The answer is A. The ordered lens should always orient at the same place as the diagnostic lens. If it does not, the cylinder axis of the lens will not align correctly with the patient's cylinder axis.
67. Referring to the question above, when the patient's new lens is received, where would you expect the new lens to orient? A. 10 degrees to the observer's left B. 10 degrees to the observer's right C. The six o'clock position D. At 90 degrees
The answer is B. "SEAL" is typically found in soft lens wearers and stands for Superior Epithelial Arcuate Lesion. "SEAL" is characterized by an epithelial lesion of 1 to 3 mm. The lesion is generally 1 mm from the superior limbus, is arcuate in shape and parallel to the limbus. It is generally considered to be the result of a soft lens that does not flex enough to conform to both the flat sclera and steeper cornea. The upper lid rubs the lens into the superior cornea, causing the epithelium to split. Discontinuing lens wear until the condition resolves and then refitting with a softer, thinner lens material will usually solve the problem.
68. "SEAL" is a condition, which is characterized by: A. A lesion in the inferior cornea B. A lesion in the superior cornea C. Edema in the corneal endothelium D. Loss of central vision
A. promote healing/relieve pain
7. A bandage hydogel lens may be used to ______ after the PRK or to protect the flap and ______ after LASIK. A. promote healing/relieve pain B. decrease healing/increase pain C. maintain tears/increase pain D. maintain tears/relieve pain
The answer is A. The keratometer readings indicate the need for a spherical back surface, which would rule out the use of a bitoric lens. A soft spherical lens would not correct the moderate amount of refractive astigmatism that is present, nor would the spherical rigid gas permeable lens. A front surface toric RGP would best meet this patient's needs since it has a spherical back surface, but has a toric front surface which would correct the residual astigmatism.
7. Which lens design would provide the best visual acuity for a patient with the following information? K's 42.00@ 180/ 42.50@90 Rx -6.75 +1.75 cx 90 A. Front surface toric rigid gas permeable B. Spherical rigid gas permeable C. Soft sphere D. Bitoric rigid gas permeable
The answer is C. Tensile strength refers to a material's ability to return to its original shape after it has been manipulated by outside forces. This is an important property in soft hydrogel lenses. The index of refraction refers to the ability of light to pass through a material. Crosslinking agents are the part of the lens material whose main purpose is to hold the polymer chains together. An elastomer is a co-polymer with many repeating polymer units.
70. The major concern in using silicone as a contact lens material is it's? A. Hydrophilic nature B. Optics C. Hydrophobic nature D. Oxygen transmission
The answer is B. Microcysts are tiny pockets of cellular debris that move through the epithelium until they appear on the surface of the cornea and are blinked away into the tear film. While they themselves do not cause pain or irritation, they are a sign that the cornea is not receiving adequate oxygen. Contact lens wearers who display microcysts should be instructed to remove their contact lenses and leave them off until the situation is resolved, which may take several weeks to months. Before resuming lens wear, the patient's situation should be evaluated and steps should be taken to increase the amount of oxygen being delivered to the cornea. This might inv9lve reducing wearing time or increasing lens Dk. Microcysts are most common in extended wear patients and these patients should be refit for daily wear only.
71. When 50 or more epithelial microcysts are noted during the slit lamp exam, the patient should be told to: A. Continue lens wear but switch to heat disinfection B. Discontinue lens wear until they go away, usually in three months C. Reduce lens wear until they go away, usually in three days D. Switch to high water content lenses and remove weekly
The answer is D. Soft contact lenses can fall victim to many contaminants. Some of them are present in care systems while others may be introduced to the lens surface by way of the patient's hands or tear film. Preservatives in care systems such as sorbic acid or potassium sorbate can cause lenses to discolor. Environmental contaminants such as make-up, newsprint and nicotine, can also discolor a soft contact lens.
72. Soft contact lenses may be discolored from coming in contact with many contaminants. Whid of the following would not discolor a soft cont act lens? A. Make-up B. Newsprint C. Nicotine D. Hydrogen peroxide
The answer is A. When manufacturing soft lenses by spin casting, the speed and amount of liquid monomer determine the thickness and power of each lens. The power curve is located on the back surface; the front surface remains constant regardless of lens power.
75. Which method of manufacturing uses centrifugal force of a known speed to spin liquid monomer in a bowl? A. Spin casting B. Cast molding C. Lathe cutting D. Hydro molding
The answer is C. Lathe cutting of soft contact lenses is done with the lens material in the dehydrated state. The CPC (central posterior curve) is cut first on the back side. The anterior surface is the power curve, and is cut after the CPC.
76. Which method of manufacturing soft lenses is done with the material in a dehydrated state while the curves are produced on both sides? A. Spin casting B. Cast molding C. Lathe cutting D. Hydro molding
The answer is B. Cast or injection molding is accomplished by injecting a liquid monomer between a male and female set of molds. These molds determine both the posterior and the anterior set of curves
77. Which method of manufacturing soft lenses uses a liquid monomer injected between molds? A. Spin casting B. Cast molding C. Lathe cutting D. Hydro molding
The answer is B. Add the over refraction's sphere power to the diagnostic lens's spherical power. This results in -2.75. Tag on the amount and axis of the cylinder found in the over-refraction (-1.75 ex 10). Since the lens rotates to the left, the amount of rotation is added to the refractive axis, so the axis of the lens ordered for the patient should be 20 degrees.
79. A diagnostic soft toric lens without cylinder has the following parameters: 8.9 -3.25 14.5 1 ½ prism ballast An over-refraction shows: +0.50 -1.75 cx 10 The diagnostic lens rotates to your left 10 degrees. What lens parameters would you order? A. 8.9 -2.75 -1.75 cx 10 14.5 B. 8.9 -2.75 -1.75 cx 20 14.5 C. 8.9 -2.75 -1.75 cx 180 14.5 D. 8.9 -3.25 -1.75 cx 180 14.5
The answer is A. The wetting angle of a rigid gas permeable material describes how a fluid spreads over the surface. It is important to remember, however, that wetting angle is a description of the material outside of the patient's natural ocular environment. Within minutes of insertion, a rigid lens is encapsulated in the natural tear mucin and the wetting angle of the material is no longer important.
8. Which of the following describes the angle that the edge of a bead of water makes with the surface of a plastic? A. Wetting angle B. Surface angle C. Bead angle D. Reflection angle
The answer is D. Increasing the overall diameter would further tighten the soft lens on the eye and would be contraindicated in this case. Decreasing the diameter would loosen the lens, but if the radius of curvature was decreased (e.g. 9.0 mm is looser than 8.7 mm}, it would counter-act the effect of decreasing the diameter. Only the combination of decreasing the diameter .and increasing the radius of curvature will loosen fit and eliminate the depression caused by a tight lens.
80. If a toric lens is too tight: A. The patient will notice post-blink clarity followed blur B. It will cause discomfort due to inferior edge standoff C. It will fail to maintain stable orientation between blinks D. The patient will notice post-blink blur followed by slow clearing
The answer is B. Epithelial cells start out in a columnar or basal shape in the posterior portion of the epithelium, flattening into wing cells out as they rise to the surface and slough off as squamous cells into the tear film.
81. The three most distinct types of cells in the epithelium in order from posterior to anterior are: A. Basal, squamous, wing B. Basal, wing, squamous C. Squamous, wing, basal D. Squamous, basal, wing
The answer is A. Knowing the layers of the cornea in order, as well as their function, is very important.
82. The five layers of the cornea in order from anterior to posterior are: A. Epithelium, Bowman ' s membrane, Strama, Descemet's membrane, Endothelium B. Epithelium, Stroma, Bowman's membrane, Descernet's membrane, Endothelium C. Epithelium, Descemet's membrane, Bowman's membrane, Stroma, Endothelium D. Epithelium, Descemet's membrane, Stroma, Bowman's membrane, Endothelium
The answer is D. The cornea must stay relatively dehydrated to remain clear. If fluid is allowed to collect in the stroma, corneal edema will occur. The endothelium is the cell layer most responsible for the removal of excess fluid through a pumping mechanism. Descemet's membrane is simply the fourth layer of the cornea and is the basement membrane next to the endothelium.
83. Which corneal layer is most responsible for deturgescence? A. Epithelium B. Strama C. Descemet's membrane D. Endothelium
The answer is B. The average tear break up time is 10-12 seconds. Any patient showing break up times of less than seven seconds should be reevaluated as a candidate for contact lens wear.
84. What is considered an average tear break -up time? A. 5-6 seconds B. 10-12 seconds C. 15-20 seconds D. 2-3 Seconds
The answer is B. Anisometropia is the term used when the refractive errors of the two eyes are very different. Patients with anisometropia are excellent contact lens candidates since contact lenses will minimize the differences in image size that are caused by large differences in spectacle lens power.
85. Anisometropia is: A. Another name for "lazy eye" B. A large difference in the refractive error of the two eyes C. A type of astigmatism D. Color blindness
The answer is A. Ectropion occurs when the eyelid turns out and away from the globe of the eye. In severe cases, dry eyes and keratitis due to exposure can develop and may be a contraindication to contact lenses. An inward turning of the eyelid is termed entropion. Rubbing of the lashes against the globe caused by an inward turning of the lids is called trichiasis.
86. Ectropion is: A. An outward turning of the eyelid B. An inward turning of the eyelid C. An inward turning of the eyelashes D. Incomplete eye closure
The answer is D. The cornea is not round, but oval, with the longest distance being horizontal.
87. The adult cornea averages: A. 9-11 mm horizontally 8-10 mm vertically B. 11-12mm horizontally 11-12mm vertically C. 10-12mm horizontally 12-14mm vertically D. 11-12mm horizontally 9-11mm vertically
The answer is C. Arcus senilus is an accumulation of fatty deposits in the stroma and is not a sign of pathology or disease. This is a common finding, occurring in nearly 50% of 50 year olds and nearly 100% of 80 year olds.
88. Arcus senilus is caused from: A. An infection B. Keratoconus C. Fat deposits in the stroma D. A low dk contact lens
The answer is A. Polymegathism is defined as the variability in the size of the endothelial cells. Hexagonality refers to the shape of the cells. Pleomorphism is a deviation in the shape or hexagonality of the cells. Morphology refers to the changes found in shape and size of a given object.
89. Deviation from the normal size of endothelial cells is called: A. Polymegathism B. Hexagonality C. Pleomorphism D. Morphology
The answer is B. The back surface of a rigid lens will usually correct only the astigmatism that is found on the surface of the cornea. Therefore, when there is significantly more astigmatism in the refraction than on the surface of the cornea, residual astigmatism is anticipated.
9. If a patient has 1.50 D of refractive cylinder and keratometer readings of 44.00@ 180/ 44 .50 @ 90, a spherical rigid gas permeable lens will: A. Give the patient their best correctable vision B. Usually result in residual astigmatism C. Fit poorly D. Be uncomfortable
The answer is C. The primary function of the corneal endothelium is to regulate the water content of the corneal stroma, which is normally 78%. The endothelium does not provide any nutrients to the stroma, nor does it contribute significantly to the refraction of light moving through the cornea.
90. The most important function of the endothelial cell layer is to: A. Provide nutrients to the stroma B. Refract light C. Regulate the water content of the stroma D. All of the above
The answer is D. The blink rate will drop from the average rate of one blink every 5 seconds during tasks that require great concentration.
91. The normal blink rate will typically drop during which of the following activities? A. Computer work B. Driving C. Reading D. Watching TV
The answer is C. If a patient with advanced keratoconus is asked to look down, the cone will push out the lower lid outlining the cone. This outward protrusion is called a Munson's sign.
92. A positive Munson's Sign is a classic sign of what condition? A. Blepharitis B. Glaucoma C. Keratoconus D. Keratitis Sicca
The answer is A. The area of the eye filled with aqueous fluid that lies behind the cornea and in front of the crystalline lens is referred to as the anterior chamber. The retina is the light-sensitive area found in the most posterior section of the eye. The choroid is the vascular portion of the eye that furnishes nourishment to the outer layers of the retina and is found between the retina and sclera. The vitreous is the transparent gelatinous material that fills the globe of the eye behind the crystalline lens.
93. Name the area of the eye that lies behind the cornea, in front of the crystalline lens and is filled with aqueous fluid. A. Anterior Chamber B. Retina C. Vitreous D. Choroid
The answer is C. A decrease in the amount of oxygen received by the cornea has been linked to the development of endothelial polymegathism, which refers to an enlargement in the size of the cells.
94. Polymegathism is thought to be related to: A. Increased ultraviolet radiation B. Keratoconus C. Oxygen deprivation D. Cataract formation
The answer is B. The cornea's refractive power is generally between 40.00 and 48.00 diopters and has a greater effect on refraction than any other ocular structure. The crystalline lens has the next greatest impact on light, with a range of 10.00 to 16.00 D. An intraocular lens placed in the eye after the crystalline lens is removed will have power, but not as much as the cornea. The retina does not have any significant influence on one's refraction.
95. The area of the eye with the greatest refractive power is the: A. Intraocular lens B. Cornea C. Crystalline lens D. Retina
The answer is D. Diuretics, decongestants and anti-depressants have all been known to decrease the volume of tears available and therefore, affect successful contact lens wear.
96. Of the following medications, which one will affect contact lens wearing the least: A. Diuretics B. Antidepressants C. Decongestants D. Cough suppressants
The answer is B. Flashes of light and a dark shadow or "curtain" along with an increased number of floaters in the patient's vision could be signs of a retinal detachment. This is an ocular emergency and any patient who notes these symptoms should be referred immediately to a physician.
97. An increase in the number of floaters in the patient's vision along with which of the following symptoms depicts a potentially vision threatening situation and should be referred to a physician immediately? A. Photophobia and burning B. Flashes of light and a dark shadow C. Visual experience of intermittent blurring D. Redness and scratchy sensation
The answer is C. Entropion is the condition in which either the upper, lower or both lids turn in towards the cornea. If lashes rub on the cornea as a result of this turning in of the lid, a bandage lens may be indicated. Chronic blepharitis may be a contraindication to extend ed wear lens usage as the risk of infection is much greater for these patients.
98. A soft extended wear bandage lens may be indicated in which of the following conditions? A. Blepharitis B. Ptosis C. Entropion D. Glaucoma
The answer is A. Aniridia is the absence of the iris. In this situation, a cosmetic iris contact lens would not only help to normalize the patient's appearance but would cut down the amount of light entering the eye and help to prevent macular damage.
99. In which type of eye condition would a cosmetic iris contact lens be most useful? A. Aniridia B. Iritis C. Iridiocyclitis D. Rubeosis
C. blepharitis.
Ch1-10. A condition associated with scales and crusting at the base of the lashes, redness, and irritation of the lid margins and a possible loss of lashes is called A. Stevens-Johnson syndrome. B. lipid abnormality. C. blepharitis. D. ocular dandruff.
D. routine lid hygiene.
Ch1-11. Therapy for and prevention of blepharitis can be accomplished by A. oral antibiotics. B. topical antibiotics. C. vitamin A. D. routine lid hygiene.
C. Entropion.
Ch1-12. The condition in which the lid margin rotates in toward the globe is called A. Distichiasis. B. Ectropion. C. Entropion. D. Trichiasis.
B. Ectropion.
Ch1-13. The condition in which the lower lid evens outward away from the globe is called A. Distichiasis. B. Ectropion. C. Entropion. D. Trichiasis.
D. Trichiasis.
Ch1-14. The acquired condition in which lashes are curved back towards the globe, but the lid itself maintains a normal position is called A. Distichiasis. B. Ectropion. C. Entropion. D. Trichiasis.
D. All of the above
Ch1-15. If the lids are unable to close completely, this may result in A. increased tear film evaporation. B. disruption of the mucin layer. C. ocular surface breakdown. D. All of the above.
D. All of the above.
Ch1-16. Ptosis can be the result of A. interference with the nerve supply to a muscle. B. long-term rigid lens wear. C. dehiscence of the levator muscle. D. All of the above.
A. 200 years.
Ch1-17. Keratoconus, as a condition, has been recognized for approximately A. 200 years. B. 150 years. C. 100 years. D. 50 years.
C. a conical reflection on the nasal cornea if a penlight is shone from the temporal side.
Ch1-18. Rizzuti's sign is A. iron deposits surrounding the base of the cone. B. fine vertical stress lines within the stroma. C. a conical reflection on the nasal cornea if a penlight is shone from the temporal side. D. scissoring of the retinoscope reflex.
B. 20%
Ch1-19. Approximatelyhowmanypatients with rheumatoid arthritis will develop keratoconjunctivitis sicca? A. 10% B. 20% C. 50% D. 70%
D. 20mm.
Ch1-2. The vertical measurement of the palpebral fissure for an average eye is A. 5mm. B. 10mm. C. 15mm. D. 20mm.
B. pancreas, insulin.
Ch1-20. Diabetes mellitus is a condition in which the ____ does not produce sufficient amounts of ___ A. pancreas, glucose. B. pancreas, insulin. C. liver, insulin. D. kidney, glucose.
D. 80%
Ch1-21. Diabetic retinopathy, in some form, affects approximately what percentage of the diabetic population? A. 10% B. 20% C. 50% D. 80%
D. All of the above
Ch1-22. Diabetics may encounter corneal complications which may include A. decreased corneal sensation. B. delayed wound healing. C. recurrent erosions. D. All of the above.
B. blepharospasm
Ch1-23. Ocular manifestations of Graves' Disease include all but A. lid retraction. B. blepharospasm. C. proptosis. D. infrequent blinks.
C. kept as wet as possible regardless of material.
Ch1-24. Contact lenses worn by patients suffering from allergic rhinitis should be A. made from a rigid material only. B. made from soft lens materials over 55% water only. C. kept as wet as possible regardless of material. D. never worn by these patients.
D. All of the above
Ch1-25. Drugs that cause a reduction in blink rate include A. antihistamines. B. muscle relaxants. C. anti-depressants. D. All of the above.
A. dilator pupillae
Ch1-3. The eyelid muscle responsible for closure of the lids is the A. dilator pupillae. B. orbicularis oculi. C. levator superioris. D. pectoral blephari.
C. Aqueous humor
Ch1-4. The anterior cornea's main source of oxygen is the A. atmosphere. B. short posterior ciliary arteries. C. aqueous humor. D. central retinal vein.
B. nebula
Ch1-5. A dense opacity of the cornea is called a A. dendrite. B. nebula. C. fovea. D. leukoma.
B. 1.336
Ch1-6. The refractive index of the tear film is A. 0.1336. B. 1.336. C. 13.36. D. The tear film does not have an index of refraction.
C. Aqueous Tear Deficiency
Ch1-7. The most common manifestation of keratoconjunctivitis sicca is A. Riley-Day Syndrome. B. Sjogren's Syndrome. C. Aqueous Tear Deficiency. D. Mucin Deficiency.
B. Decreased corneal sensation associated with contact lens wear.
Ch1-8. Contact lens wear has been associated with decreased tear production most possibly due to A. The pressure from the lens on the lacrimal gland. B. Decreased corneal sensation associated with contact lens wear. C. Increased bacteria found in the tear film from contact lens use. D. The lens absorbing the tear film.
A. vitamin A deficiency.
Ch1-9. Mucin deficiency is most commonly caused by A. vitamin A deficiency. B. an abundance of aqueous. C. a decrease in production by the Krause and Wolfring glands. D. lid abnormality.
A. two
Ch10-1. There are ______ primary categories of astigmatism. A. two B. three C. four D. five
C. dramatically
Ch10-10. Availability of silicone hydrogel (SiHy) soft lenses has contributed __ to the success in fitting piggyback lens systems. A. nothing B. very little C. dramatically D. somewhat
C. 2
Ch10-11. There are ______ methods for fitting piggyback lenses. A. 5 B. 6 C. 2 D. 3
B. placing a SiHy lens on the eye/taking a keratometric measurement
Ch10-12. Tandem lens fitting is accomplished by first ______ and then ______ A. rinsing the eye with saline/placing a SiHy lens on the eye B. placing a SiHy lens on the eye/taking a keratometric measurement C. placing an RGP lens on the eye/placing a SiHy lens on the eye D. placing an RGP lens on the eye/taking a keratometric measurement
B. irregular astigmatisms.
Ch10-13. Standard HEMA and silicone-hydrogel soft lenses may be safely used following LASIK, but they are not capable of fully correcting A. myopic eyes. B. irregular astigmatisms. C. hyperopic eyes. D. regular astigmatisms.
D. Contact lenses/corneal surgery.
Ch10-14. ______ offer an option to rehabilitate patients when visually symptomatic following ocular trauma or ______ A. Spectacles/dry eyes. B. Spectacles/induced astigmatism. C. Contact lenses/dry eyes. D. Contact lenses/corneal surgery.
D. 10-24
Ch10-2. Depending on the laser device, ablation zone diameters and algorithms used, a depth of ______ microns of corneal ablation approximately equals one diopter of corneal power change. A. 1-5 B. 5-10 C. 25-35 D. 10-24
B. is not a direct correlation
Ch10-3. There ______ between corneal refractive power and corneal curvature in the periphery. A. is equal zone influence B. is not a direct correlation C. is a direct correlation D. are simple calculations that can be made
A. measuring corneal curvature.
Ch10-4. Topographic devices are limited to ______ A. measuring corneal curvature. B. measuring corneal power. C. measuring peripheral power. D. central power measurement.
D. 6
Ch10-5. Contrast sensitivity decreases despite normal visual acuity immediately following surgery and then largely recovers after ______ months post-op. A. 3 B. 4 C. 5 D. 6
D. 6
Ch10-6. There are ______ general approaches to fitting contact lenses on post-surgical corneas. A. 3 B. 4 C. 5 D. 6
D. hyperopic refractive shifts
Ch10-7. The 10 year results of the PERK Study indicate that the majority of post-RK patients will experience_ over time. A. no refractive shifts B. astigmantic refractive shifts C. myopic refractive shifts D. hyperopic refractive shifts
A. oblate.
Ch10-8. The post-LASIK corneal topography is A. oblate. B. prolate. C. ortholate. D. spherical.
A. refractive ametropias.
Ch10-9. LASIK has become the surgical treatment of choice for A. refractive ametropias. B. refractive emetropias. C. astigmatism. D. presbyopia.
C. astigmatism.
Ch11-1. Currently, there are surgical procedures that can correct all of the following except A. hyperopia. B. myopia. C. astigmatism. D. presbyopia.
A. 10%
Ch11-10. Approximately how many ophthalmologists in the United States perform RK? A. 10% B. 25% C. 50% D. 90%
B. photoablation.
Ch11-11. The excimer laser works by A. surgical incisions. B. photoablation. C. fresnel prisms. D. adding tissue to the stromal bed.
D. All of the above.
Ch11-13. Which of the following affects the successful outcome of a PRK procedure? A. Hydration of the corneal tissue B. Centration of the ablation zone C. Energy density of the laser beam D. All of the above.
B. asymmetric ablation.
Ch11-14. The main difference between PRK and PRKa is the A. fluence of the laser. B. asymmetric ablation. C. fixation of the pupil. D. method of removing the epithelium.
C. automated lamellar keratotomy.
Ch11-15. ALK stands for A. automated lasik keratotomy. B. assisted laminated keratograph. C. automated lamellar keratotomy. D. automated lamellar keratometry.
B. shaped like a plus lens.
Ch11-16. To correct myopia by removing a lenticule of tissue from the corneal stroma, the lenticule must be A. shaped like a minus lens. B. shaped like a plus lens. C. shaped like an astigmatic lens. D. shaped like a toric lens.
A. Lamellar keratoplasty
Ch11-17. Which procedure requires re-suturing of the cornea? A. Lamellar keratoplasty B. RK C. PRK D. PRKa
C. the use of laser versus the microkeratome to produce the Rx.
Ch11-18. The main difference between ALK and LASIK procedures is A. the use of the microkeratome to create a corneal flap. B. the direction of the corneal resection. C. the use of laser versus the microkeratome to produce the Rx. D. the direction of the flap produced.
A. less chance of complete loss of the cap.
Ch11-19. One advantage to creating a corneal flap in ALK and LASIK is A. less chance of complete loss of the cap. B. better refractive error achieved. C. the ability to correct astigmatism. D. a greater fee for the surgeon.
A. Snellen.
Ch11-2. The man considered to be the founding father of refractive surgery is A. Snellen. B. Ruiz. C. Barraquer. D. Burrato.
C. the position of the corneal flap.
Ch11-20. Upside Down LASIK refers to A. the position of the patient. B. the position of the laser. C. the position of the corneal flap. D. the position of the astigmatism.
B. development and location of haze.
Ch11-21. The most notable difference(s) between long-term post-operative recovery in PRK and LASIK is A. development of residual astigmatism. B. development and location of haze. C. pain management of the patient. D. development of hyperopia.
D. All are challenges
Ch11-22. Which of the following is not a challenge to the contact lens practitioner who is fitting the post-refractive surgery patient? A. Reduced corneal sensitivity B. Irregular astigmatism C. Patient's dissatisfaction with the need to re-introduce contact lenses D. All are challenges
D. All of the above.
Ch11-23. Corneal sensation is imperative for A. stimulation of the protective blink. B. wound healing. C. corneal health. D. All of the above.
D. be avoided.
Ch11-24. Extended wear modalities for post-refractive surgery patients should A. only be applied 4-6 months after surgery. B. be used no more than six consecutive nights before lens removal. C. be used for RK patients only. D. be avoided.
B. understanding the location and axis of the post-op astigmatism.
Ch11-25. CAVs are useful for A. determining the post-operative Rx. B. understanding the location and axis of the post-op astigmatism. C. determining the presence of corneal haze. D. evaluating the endothelial cell count.
B. 25%
Ch11-3. Approximately what percentage of the U.S. population is myopic? A. 10% B. 25% C. 50% D. 70%
A. radial keratotomy.
Ch11-4. An example of an incisional procedure would be A. radial keratotomy. B. photorefractive keratectomy. C. thermokeratoplasty. D. LASIK.
B. photorefractive keratectomy.
Ch11-5. An example of a lamellar procedure would be A. radial keratotomy. B. photorefractive keratectomy. C. thermokeratoplasty. D. intrastromal corneal ring.
C. thermokeratoplasty.
Ch11-6. An example of a heat-induced shrinkage procedure would be A. radial keratotomy. B. photorefractive keratectomy. C. thermokeratoplasty. D. intrastromal corneal ring.
A. LASIK.
Ch11-7. Currently, the most commonly performed refractive surgery procedure is A. LASIK. B. photorefractive keratectomy. C. thermokeratoplasty. D. radial keratotomy.
A. radial keratotomy.
Ch11-8. RK stands for A. radial keratotomy. B. refractive keratomileusis. C. refractive keratotomy. D. radial keratometry.
D. 88; 20/40
Ch11-9. In the PERK study, __ % of the patients received vision or better. A. 40; 20/20 B. 40; 20/40 C. 88; 20/20 D. 88; 20/40
C. the presence of active pathology.
Ch12-1. The only real non-indication for contact lenses following refractive surgery is A. irregular astigmatism. B. previous contact lens failure. C. the presence of active pathology. D. photophobia.
D. 9.5mm to 10.5mm
Ch12-10. What is the diameter of most of the rigid plateau lenses? A. 8.0mm to 9.0mm B. 8.5mm to 9.5mm C. 8.0mm to 10.0mm D. 9.5mm to 10.5mm
B. diagnostic lens evaluation and over-refraction.
Ch12-11. The most effective approach to fitting the post-refractive surgical cornea is A. empirical. B. diagnostic lens evaluation and over-refraction. C. keratometer readings and spectacle prescription given to the laboratory. D. corneal mapping.
A. approximate the mean of the pre-operative keratometer readings.
Ch12-12. Base curve selection for fitting a spherical or bi-aspheric rigid lens should A. approximate the mean of the pre-operative keratometer readings. B. be as flat as possible. C. be the mean of the pre-operative and postoperative keratometer readings. D. allow for the application of toric curves.
D. fixation dots placed on the front of the keratometer.
Ch12-13. The keratometer can be used to evaluate the peripheral topography of the cornea by using A. a Wratten #12 filter. B. an Innes disc. C. a central fixation dot. D. fixation dots placed on the front of the keratometer.
B. a yellow filter.
Ch12-14. Enhancement of the fluorescein pattern can be achieved with the use of A. a green filter. B. a yellow filter. C. the white light. D. using extra fluorescein.
A. to be similar to the pre-operative contact lens power.
Ch12-15. When utilizing a rigid lens over a post RK cornea, you could expect the contact lens power A. to be similar to the pre-operative contact lens power. B. to be plano. C. to be hyperopic. D. to be greater than the pre-operative contact lens power.
D. add half the pre-operative prescription to the current mean "K".
Ch12-16. To estimate a patient's pre-operative mean "K" reading, A. add the pre-operative prescription to the current flat "K". B. add the pre-operative prescription to the current steep "K". C. add the pre-operative prescription to the current mean "K". D. add half the pre-operative prescription to the current mean "K".
B. 41.50D
Ch12-17. Given the following information, what would be the estimated pre-operative "K" reading in the following example? Current "K"s: 38.00@ 180/40.00@ 90 Pre-operative Rx -5.00D A. 40.50D B. 41.50D C. 43.00D D. 44.00D
B. mid-peripheral light touch with central pooling.
Ch12-18. A bi-aspheric rigid lens on a post-refractive surgical cornea will exhibit A. an alignment pattern of fluorescein. B. mid-peripheral light touch with central pooling. C. little or no edge lift. D. inferior positioning.
C. had non-incisional refractive surgery.
Ch12-19. Soft lenses may safely be considered for patients who have A. undergone any type of refractive surgery. B. undergone only RK procedures. C. had non-incisional refractive surgery. D. undergone only astigmatic procedures.
A. provide a safe, effective contact lens fit.
Ch12-2. The role of the contact lens professional is to A. provide a safe, effective contact lens fit. B. be the Complaints Department. C. be the lightning rod for the patient 's frustration over their unsuccessful surgical procedure. D. discuss refractive surgery techniques.
A. utilize standard designs as with normal corneas.
Ch12-20. When fitting post PRK or post LASIK patients with soft lenses, A. utilize standard designs as with normal corneas. B. fit the lens as tight as possible to avoid lens flexure. C. fit the lens as thick as possible to reduce lens movement. D. utilize custom lens designs only.
C. a steep central lens to cornea relationship.
Ch12-21. Keratometry over a soft lens which shows blurred mires which clear immediately after blinking then blur again indicates A. a flat peripheral lens to cornea relationship. B. residual astigmatism. C. a steep central lens to cornea relationship. D. an aspheric lens in situ.
A. fluctuating vision due to flexure and wrinkling of the lens.
Ch12-22. It is important that a soft lens aligns with the central cornea in order to avoid A. fluctuating vision due to flexure and wrinkling of the lens. B. peripheral pooling of tears. C. mid-peripheral impingement. D. corneal hypoxia.
D. is thicker than a standard soft lens.
Ch12-23. The optical zone of a Harrison PRS soft lens A. is aspheric. B. incorporates a toric configuration. C. is thinner than a standard soft lens. D. is thicker than a standard soft lens.
D. retinoscope calibration.
Ch12-24. All the variables listed below are important in achieving a successful contact lens result except A. lens materials. B. lens designs. C. wearing schedules. D. retinoscope calibration.
C. Follow-up care
Ch12-25. Which element will enable the fitter to ensure the patient's cornea, refraction, and ocular health remain stable? A. The use of a soft contact lens B. The presence of sutures C. Follow-up care D. Ocular medications
D. All of the above
Ch12-3. Results of a post-refractive surgical contact lens fitting should be all of the following except A. optimal comfort for the patient. B. improved visual acuity for the patient. C. alignment of the corneal surface with the contact lens. D. All the above.
B. tear stagnation.
Ch12-4. Central iron stains in post-refractive surgical cases is an indication of A. irregular astigmatism. B. tear stagnation. C. cross cut incisions. D. excessive mass displacement of the contact lens.
C. RK
Ch12-5. Which refractive surgery procedure typically results in the greatest irregularity of the corneal midperiphery? A. Phototherapeutic keratectomy B. LASIK C. RK D. ALK
B. corneal vascularization in the incisions.
Ch12-6. The primary concern in fitting a soft lens after radial keratotomy is A. lens deposits. B. corneal vascularization in the incisions. C. lens flexure. D. myopic creep.
B. create a steeper central profile than peripheral profile.
Ch12-7. Hyperopic procedures A. create a steeper peripheral profile than central profile. B. create a steeper central profile than peripheral profile. C. can only be accomplished with intrastromal rings. D. Does not exist yet.
D. All of the above.
Ch12-8. Contact lenses may be needed after refractive surgery because of A. aniseikonia. B. irregular astigmatism. C. corneal opacities. D. All of the above.
D. All of the above
Ch12-9. Which rigid lens designs are available for the post refractive surgery patient? A. Multi-curve B. Aspheric C. Bi-aspheric D. All of the above
B. basic/curvature.
Ch13-1. The keratometer is a/ an instrument used to measure the anterior corneal A. basic/ diameter. B. basic/curvature. C. advanced/ diameter. D. advanced/ curvature.
D. 40
Ch13-10. Scanning slit instruments use a high-resolution video camera. The camera captures ______ light slits in one to two seconds. A. 10 B. 20 C. 30 D. 40
B. anterior and posterior surfaces
Ch13-11. The Scheimpflug camera allows for an analysis of both the of the cornea. A. stroma and limbus B. anterior and posterior surfaces C. endothelium and limbus D. apex and epithelium
A. retinal imaging/non-invasive
Ch13-12. Optical coherence tomography is ideal for ______ but it is also a method of cross-sectional scanning of the cornea that is A. retinal imaging/non-invasive B. retinal imaging/invasive C. corneal imaging/invasive D. general eye imaging/non-invasive
D. solid-state electronic device/light
Ch13-13. A charged-coupled device (CCD) is a/an ______ used to gather ______. A. lens system/light B. electrified mirror/electrons C. lens system/photons D. solid-state electronic device/light
A. sophisticated
Ch13-2. More ______ instrumentation is necessary for interpretation of the topography of the cornea to ensure the most desirable fitting of contact lens correction. A. sophisticated B. simple C. types of D. viewing
D. concentric rings
Ch13-3. Many topographical instruments today utilize the technology based on the principles of the Placido Disk. This technology consists of a series of illuminated ______ that are projected to the eye. A. green dots B. small triangles C. small squares D. concentric rings
A. two
Ch13-4. There are ______ types of projection techniques used for a Placido disk type topographer. A. two B. three C. four D. five
A. four
Ch13-5. Depending on the topographical instrument, there may be 500 to 22,000 points that are analyzed. That is significantly greater than the ______ cardinal points measured by the manual keratometer. A. four B. nine C. twelve D. fifteen
C. 8.9 to 10mm
Ch13-6. Depending on the instrument, a small cone Placido disk measures of corneal surface. A. 5.9 to 7.8mm B. 7.9 to 9mm C. 8.9 to 10mm D. ll.0 to 14mm
B. several standard types
Ch13-7. Topographers utilize ______ of displays for the data captured. A. five advanced types B. several standard types C. two standard types D. three advanced types
A. normalized
Ch13-8. A/an ______ type of map may be easier for a practitioner to use in contact lens design and evaluation. A. normalized B. axial C. tangential D. absolute
C. epithelial surface/tear film
Ch13-9. Topographical imaging requires an intact ______ and ______ A. palpebral conjunctiva/in-focus retina B. conjunctiva/limbus C. epithelial surface/tear film D. sclera/tear film
C. They should only be used to secure financing.
Ch14-1. Which of the following statements are not true regarding business plans? A. They organize the business' goals, strategies and actions. B. They should be used by every business. C. They should only be used to secure financing. D. A good business plan makes the practice look toward the future.
A. the clinician's credentials.
Ch14-10. Practice brochures should highlight all of the following except A. the clinician's credentials. B. products offered by the practice. C. hours of availability. D. hours when the office is closed.
B. 7%
Ch14-11. If you conduct a patient satisfaction survey, what is considered a highly successful response rate? A. 5% B. 7% C. 10% D. 20%
D. Simple and complex.
Ch14-12. Types of questions that are best utilized on a patient satisfaction survey are A. Direct and indirect. B. Open and closed. C. Behavioral and positioning. D. Simple and complex.
D. All of the above.
Ch14-13. Patient satisfaction surveys should A. maintain confidentiality of the patient . B. address "need to know" issues. C. include questions that will lead to action on the part of the practice. D. All of the above.
C. Marketing
Ch14-14. What single factor can have the greatest impact on the success of a contact lens practice? A. Staff B. Newsletters C. Marketing D. Recall system
D. be completed by filling out an evaluation form once a year.
Ch14-15. Performance reviews should A. be done at a staff meeting. B. be conducted more frequently for new employees. C. only be done when a problem arises with a staff member. D. be completed by filling out an evaluation form once a year.
A. it may be considered a legal document relative to employee issues.
Ch14-16. All of the following statements regarding office policy manuals are true except A. it may be considered a legal document relative to employee issues. B. it should be reviewed at least annually. C. it should be very specific so there is no room for question. D. it should not be viewed by new employees until they have been with the practice for at least six months.
C. essential insurance information.
Ch14-17. A practice brochure should include all of the following except A. office hours. B. an explanation of the contact lens fitting process. C. essential insurance information. D. names and addresses of other practices in the area.
B. sending recall notices.
Ch14-18. A procedure that can differentiate you from most of your competitors in your patients' eyes is A. follow-up calls on the purchase of contact lenses or spectacles. B. sending recall notices. C. direct mailing of contact lenses. D. conducting staff meetings.
D. managed care.
Ch14-19. Your greatest potential source of future revenue is A. direct mail. B. previous and current customers. C. spectacles. D. managed care.
B. what is happening in your city or region.
Ch14-2. Market analysis describes A. your practice. B. what is happening in your city or region. C. who your current patient/customers are and who you would like them to be. D. how the practice operates.
D. an office policy manual outlining your fees.
Ch14-20 . An important first step in contact lens financial management is A. good phone skills. B. a good recall system. C. an investment in a sophisticated computer system. D. an office policy manual outlining your fees.
A. internal and external.
Ch14-3. Two categories of advertising are A. internal and external. B. audio and visual. C. advertising and brochures. D. image and reactive.
B. it is 5 to 10 times more expensive to add new patients.
Ch14-4. When comparing the cost of adding new patients to your practice versus keeping your current patients, A. it is 5 to 10 times less expensive to add new patients. B. it is 5 to 10 times more expensive to add new patients. C. it is 5 to 10 times more expensive to keep current patients. D. it is 15 to 20 times more expensive to add new patients.
D. intuition.
Ch14-5. Marketing decisions should not be based on A. patient demographics. B. market demographics. C. database gathering. D. intuition.
D. All of the above.
Ch14-6. Growth of a contact lens practice has key components in A. retaining present patient/customers. B. recruiting new patient/customers. C. regaining lost patient/customers. D. All of the above.
D. 13 to 18 %
Ch14-7. What percentage of the annual contact lens practice's revenue should be designated for advertising? A. 1 to 2 % B. 3 to 8 % C. 10 to 15 % D. 13 to 18 %
B. radio ad.
Ch14-8. For those practitioners who feel uncomfortable with advertising, an effective, dignified practice promotion tool is the A. newsletter. B. radio ad. C. direct phone calls. D. direct mail with coupons.
C. call them to discuss the case.
Ch14-9. When a practitioner refers a patient to your practice, it is considered standard practice to A. fax them a copy of your chart notes. B. mail them a written acknowledgment. C. call them to discuss the case. D. take them out to lunch.
A. minimizing potential complications associated with contact lens wear.
Ch2-1. Assuring that the ocular surface is healthy and able to support soft contact lenses, gas permeable lenses, or scleral lenses will benefit the patient by A. minimizing potential complications associated with contact lens wear. B. maximizing potential complications associated with contact lens wear. C. changing their spectacle Rx to more plus. D. reducing photophobic effects.
B. Fluorescein and Rose Bengal
Ch2-10. ___________ are the two most common dye tests for evaluation of the cornea and conjunctiva! surfaces. A. Fluorescein and Royal Blue B. Fluorescein and Rose Bengal C. Rose Bengal and Cobalt Blue D. Rose Bengal and Cobalt Blue
D. Increased tear osmolarity
Ch2-11. Which of the following is thought to be the central condition that leads to the ocular surface damage and symptoms seen in dry eye? A. Decreased tear osmolarity B. Increased tear volume C. Excessive meibomian gland function D. Increased tear osmolarity
A. two
Ch2-12. Dry eye has been divided into _ _ __major subtypes based on etiology. A. two B. three C. four D. five
B. autoimmune
Ch2-13. Sjogren dry eye syndrome is a-an _____ disease affecting the lacrimal and salivary glands. A. bacterial B. autoimmune C. viral D. fungal
C. epiphora.
Ch2-14. Subjective symptoms involved in the diagnosis of dry eye include all of the following except A. foreign body sensation. B. burning and stinging. C. epiphora. D. photophobia, and ocular fatigue.
B. Tear supplementation
Ch2-15. Tear supplementation is the mainstay of treatment in all degrees of dry eye severity. A. Vitamin supplementation B. Tear supplementation C. Nutrition therapy D. Organic supplementation
A. longer durations than
Ch2-16. Due to their higher viscosity, ocular ointments and gels can coat the ocular surface for ______ liquids and are useful during sleep when aqueous tear production is normally decreased. A. longer durations than B. shorter durations than C. much shorter durations than D. equal durations as
B. beneficial
Ch2-17. Punctal occlusion is _____ in cases of aqueous tear deficiency dry eye. A. not beneficial B. beneficial C. not useful D. not considered
D. have both been found to be clinically beneficial in the treatment of dry eye.
Ch2-18. Topical cyclosporin A and topical corticosteroids A. have neither been found to be clinically beneficial in the treatment of dry eye. B. have not been studied in the treatment of dry eye. C. need to be used together in the treatment of dry eye. D. have both been found to be clinically beneficial in the treatment of dry eye.
D. the sensory eyelash nerves.
Ch2-2. The ocular surface comprises all of the following, except A. the epithelium of the cornea and conjunctiva. B. the main and accessory lacrimal glands. C. the supporting adnexal structures of the eyelids. D. the sensory eyelash nerves.
B. can worsen pre-existing dry eye.
Ch2-3. Prior ocular surgery, including refractive surgery A. can lessen pre-existing dry eye. B. can worsen pre-existing dry eye. C. has no impact on pre-existing dry eye. D. is of no concern regarding pre-existing dry eye.
D. three
Ch2-4. Recent studies indicate that the precorneal tear film is approximately ____ microns thick. A. one B. five C. ten D. three
A. design, closely
Ch3-6. There are strategies in the ____ and selection of a custom soft contact lens for patients with irregular corneal astigmatism that can optimize the final visual outcome. In many cases, these custom designs can ____ approach the visual quality provided by a well-centered, non-flexing gas permeable lens material. A. design, closely B. diameter, somewhat C. base curve, somewhat D. flexure, closely
C. central
Ch3-7. The primary soft contact lens parameter by which we enhance visual acuity in the irregular astigmat, beyond customary sphere and cylinder power, is ____ contact lens thickness. A. peripheral B. edge C. central D. mid-peripheral
D. 0.08mm to 0.18mm.
Ch3-8. In a standard off the rack contact lens, the average center thickness ranges from A. 2.0mm to 2.5mm. B. 1.0mm to 1.5mm. C. 0.8mm to 1.3mm. D. 0.08mm to 0.18mm.
B. 5-7
Ch4-10. During removal of a hybrid contact lens, the lens is squeezed at __ o'clock and __ o'clock on the soft skirt. A. 3-9 B. 5-7 C. 12-6 D. 2-11
B. stability - crisp visual acuity
Ch4-2. The purpose of piggybacking was to use the soft lens to aid lens centration and ____ and the gas permeable lens for ____. A. coverage - centration B. stability - crisp visual acuity C. crisp visual acuity - stability D. eyelid interaction - centration
C. 1984
Ch4-3. In _____, after years of development, the FDA approved a hybrid lens that would be marketed as the Saturn II lens. A. 1979 B. 1981 C. 1984 D. 1988
D. lack of proper centration.
Ch4-4. Problems with early hybrid contact lenses included all the following except A. low oxygen transmission through both the gas permeable and soft lens materials. B. a tendency for the lens to adhere to the eye. C. separation of the gas permeable lens from the skirt. D. lack of proper centration.
A. SynergEyes, Inc.
Ch4-5. In 2001, Quarter Lambda Technologies, Inc. (now known as ______ ) received IRB approval to begin the creation of the first of four hybrid contact lens designs. A. SynergEyes, Inc. B. Boston, Inc. C. Vistakon, Inc. D. Hybrid, Inc.
B. the newer lenses have GP and Soft Lens materials with much higher Dks.
Ch4-6. A significant difference between older design hybrid lenses and new design hybrid lenses is that A. the newer lenses do not have a soft skirt. B. the newer lenses have GP and Soft Lens materials with much higher Dks. C. the newer lenses have much better centration capability. D. the newer lenses are available with greater sag dimensions.
C. poly-hema skirt
Ch4-7. High molecular weight fluorescein is necessary when fitting hybrid contact lenses due to the __ to avoid absorption of the dye. A. gas permeable center B. edge-lift of the lens C. poly-hema skirt D. apical clearance of the lens
D. 3
Ch4-8. There are __ different techniques that can be used for insertion of new hybrid contact lenses. A. 6 B. 5 C. 4 D. 3
A. air bubbles under the lens.
Ch4-9. Prior to insertion, it is important that the hybrid contact lens be filled with saline to prevent any A. air bubbles under the lens. B. edge-adherence. C. fluorescein absorption. D. off-centering of the lens.
B. glass/PMMA
Ch5-1. Contact lenses were made of ______ in the late 1800s and in the 1930s to 1980s ______ plastic replaced this earlier material. A. gelatin/PMMA B. glass/PMMA C. gelatin/HEMA D. glass/HEMA
A. interfere with/discomfort
Ch5-10. After insertion of a scleral lens, the wearer checks to ensure there are no bubbles of air trapped behind the lens. Bubbles that migrate into the visual axis will ______ vision and/or cause ______ due to corneal drying behind the bubble. A. interfere with/discomfort B. interfere/ centration issues C. enhance/increased comfort D. enhance/ discomfort
B. haptic zone.
Ch5-11. With scleral lens designs, the peripheral fitting zone is referred to as the A. secondary zone. B. haptic zone. C. vault zone. D. centering zone.
C. asymmetric
Ch5-12. The sclera becomes more ______ the further away from the limbus, increasing the degree of difficulty to fit the eye with a scleral contact lens. A. thick B. dense C. asymmetric D. symmetric
D. lubricity.
Ch5-13. Non-preserved sterile saline lacks A. salt. B. tonicity. C. osmolitic pressure. D. lubricity.
A. the base curve is not the primary fitting curve
Ch5-14. Since mini-scleral and scleral lenses fully vault the cornea, ______ in these lens designs. A. the base curve is not the primary fitting curve B. the base curve is the primary fitting curve C. the base curve is not calculated D. the base curve is moved to the periphery
C. less complicated
Ch5-15. Gas permeable lenses in the scleral lens category are often ______ to fit than corneal lenses when complex corneal topographies are involved. A. equally complicated B. more complicated C. less complicated D. less desirable
B. all
Ch5-16. Because the scleral lens vaults the cornea, ______ corneal fitting issues are avoided. A. no B. all C. 75% of D. 50% of
A. similar to/better than
Ch5-17. The comfort of scleral lenses are ______, if not ______ hybrid and soft lenses, particularly with patients who complain of dry eye. A. similar to/better than B. worse than/much worse than C. much worse than/equal to D. similar to/worse than
D. 26mm
Ch5-2. With the emergence of high Dk oxygen permeable lens blanks available in large diameters, up to ______, the feasibility of scleral lenses as an option for vision correction has re-emerged. A. 15mm B. 19mm C. 22mm D. 26mm
C. being unable to obtain clear vision.
Ch5-3. Concerns that many patients have regarding scleral contact lenses include all of the following, except A. putting such a large lens on one's eye. B. being unable to get the lens off the eye. C. being unable to obtain clear vision. D. the training period involved for successful wear.
D. annually.
Ch5-9. Contact lens cases used with scleral contact lenses should be replaced A. monthly. B. quarterly. C. semi-annually. D. annually.
B. polymerization.
Ch6-1. A polymer is formed by chemically linking individual molecular units in a reaction called A. chemists formula. B. polymerization. C. molecule unitization. D. monomerizing.
B. PMMA (polymethylmethacrylate)/20mm to 26mm.
Ch6-10. Symblepharon rings are primarily __ and come in various sizes from A. HEMA (hydroxyethylmethacrylate)/ 10mm to 15mm. B. PMMA (polymethylmethacrylate)/20mm to 26mm. C. PMMA (polymethylmethacrylate)/15mm to 19mm. D. HEMA (hydroxyethylmethacrylate)/16mm to 21mm.
A. protective covering.
Ch6-2. The soft lens was not invented to become a A. protective covering. B. plastic mesh. C. mini corneal lens. D. GPC causing material.
D. sutures.
Ch6-3. Hydrogels have been successfully developed for all the following except A. soft contact lenses. B. wound dressings. C. drug delivery. D. sutures.
C. extremely effective
Ch6-4. Hydrogel lenses, when utilized as therapeutic bandages are ______ in promoting epithelial healing. A. not at all effective B. somewhat effective C. extremely effective D. moderately effective
D. control leakage/aid in general comfort
Ch6-5. The presence of a hydrogel lens can help ______ around suture tracks and ______ for the patient. A. increase leakage/decrease photophobia B. decrease impingement/increase discomfort C. control leakage/increase discomfort D. control leakage/aid in general comfort
B. frequently
Ch6-6. Silicone hydrogel lenses are ______ utilized following PRK and LASIK. A. never B. frequently C. always D. almost never
C. very short term/close
Ch6-8. Unlike most hydrogel lens applications, a therapeutic lens must fit snugly against the cornea and with minimal movement to achieve its goal and thus the __ use and __ monitoring by the surgeon is mandatory. A. long-term/some B. short-term/some C. very short term/close D. long-term/close
B. drug carriers.
Ch6-9. Drug delivery via a hydrogel polymer is an area of ongoing research. In this use, hydrogel polymers are utilized as A. vision correction devices only. B. drug carriers. C. UV protective devices. D. drug replacements.
C. 9 years
Ch7-1. Beyond what age will uncorrected vision problems cause permanent impairment in visual development? A. 3 years B. 6 years C. 9 years D. 12 years
B. Allen cards
Ch7-10. Which of the following is used to measure visual acuity for children who can't read? A. Snellen chart B. Allen cards C. Keratometer D. "O " game
D. Strabismus.
Ch7-11. The slit lamp is critical to checking A. Movement and centering of contact lenses. B. Corneal measurements. C. Binocularity and visual acuity. D. Strabismus.
C. the same as adults.
Ch7-12. Evaluating fluorescein patterns should be A. more difficult with children than adults. B. less difficult with children than adults. C. the same as adults. D. best done in the operating room when done with children.
B. should never be done with infants.
Ch7-13. Patching A. is always optional. B. should never be done with infants. C. forces the child to use the weaker eye. D. forces the child to use the stronger eye.
A. vinyl patches are used
Ch7-14. Patching is most effective when A. vinyl patches are used. B. begun on the same day as contact lenses. C. light is completely eliminated from the patched eye. D. done only when the child is in the right frame of mind.
C. increased hyperopic correction.
Ch7-15. A possible sign of glaucoma in a small child is/are A. increased corneal diameter. B. decreased myopic correction. C. increased hyperopic correction. D. None of the above.
B. Soft
Ch7-16. Which type of lens material is appropriate for children? A. GP B. Soft C. Silicone D. All of the above.
C. 48.25 D.
Ch7-17. Keratometric readings at birth average A. 55.25 D. B. 51.25 D. C. 48.25 D. D. 45.25 D.
A. preservative-free and effective.
Ch7-18. Appropriate care systems for children are A. preservative-free and effective. B. full of preservatives and effective. C. preservative-free and complex. D. complex and effective.
D. It's not important to involve the parent
Ch7-19. Which are ways of helping a parent support the contact lens program? A. Use terms the parent can understand B. Threaten them C. Stickers D. It's not important to involve the parent
A. lntraocular lens
Ch7-2. Which of the following is the preferred method of correcting vision after monocular cataract surgery for infants? A. lntraocular lens B. Contact lens C. Aphakic spectacles D. None of the above.
D. Stickers
Ch7-20. What is not a way of rewarding a child for contact lens success? A. Time off from contact lens wear B. Treats C. Hugs D. Stickers
D. Larger HVID, steeper corneal measurement
Ch7-21. How does an infant's eye compare to an adult's? A. Smaller HVID, flatter corneal measurement B. Smaller HVID, steeper corneal measurement C. Larger HVID, flatter corneal measurement D. Larger HVID, steeper corneal measurement
D. -1.50 D.
Ch7-22. Aphakic patients who are not yet walking should have their contact lens correction adjusted by A. +3.00 D. B. -3.00 D. C. +1.50 D. D. -1.50 D.
C. Burton lamp
Ch7-23. Which instrument(s) is/are helpful in a pediatric practice? A. Handheld slit lamp B. Handheld keratometer C. Burton lamp D. All of the above.
D. they should be interpreted the opposite of an adult's.
Ch7-24. When evaluating fluorescein patterns for an RGP lens on a child A. evaluate as you would an adult. B. never use the blue light. C. the handheld keratometer works best. D. they should be interpreted the opposite of an adult's.
A. wait until they are asleep
Ch7-25. To insert and remove a contact lens on an infant, it may be necessary to A. wait until they are asleep. B. swaddle them. C. straddle them. D. bribe them.
A. injury to the eye.
Ch7-3. Strabismus is A. injury to the eye. B. misalignment of the eyes. C. a cosmetic defect. D. the pathway of light through the iris.
C. Aqueous humor
Ch7-4. Amblyopia can occur with which of the following visual problems? A. Atmosphere B. Short posterior ciliary arteries C. Aqueous humor D. Central retinal vein
B. Trauma
Ch7-5. Which of the following is not a reason for fitting contact lenses on children? A. Anisometropia B. Trauma C. Presbyopa D. Strabismus
A. 20/80.
Ch7-6. At birth, the average child has a visual acuity approximating A. 20/80. B. 20/40. C. 20/200. D. 20/25.
B. Contacts are easier to take off than glasses
Ch7-7. Which of the following is a reason for fitting contacts vs. glasses on children? A. Glasses break less often B. Contacts are easier to take off than glasses C. Contacts give a more accurate picture of the world D. Highly corrected glasses offer a cosmetic benefit
C. Play word associations
Ch7-8. Which of the following will help you take "K" readings on a small child? A. Play a game B. Straddle them C. Play word associations D. Be firm and intimidating
C. OD +15.00 D, OS Plano.
Ch7-9. An example of anisometropia would be A. OD Plano, OS -1.00 D. B. OD -15.00 D, OS -15.00 -2.00 x 90. C. OD +15.00 D, OS Plano. D. OD +1.00 D, OS -0.50.
B. reshaping the cornea temporarily.
Ch8-1. Orthokeratology is a system of A. reshaping the sclera permanently. B. reshaping the cornea temporarily. C. reshaping the cornea permanently. D. re-vascularizing the limbus permanently.
A. can range from 1-90 years of age.
Ch8-1. The age of patients requiring a penetrating keratoplasty A. can range from 1-90 years of age. B. is always over 40 years old. C. is not a factor in post-surgical success. D. is always under 50 years old.
C. an RGP lens does not position properly.
Ch8-10. A custom soft toric lens may be indicated on a penetrating keratoplasty patient when A. the peripheral topography is abnormal. B. a good visual potential can be achieved with a refraction. C. an RGP lens does not position properly. D. All of the above.
D. Have a spare pair of Ortho-K contact lenses
Ch8-10. What is the best alternative patient option in case a lens is lost or damaged? A. Wear one lens only B. Have them use soft lenses C. Wear glasses D. Have a spare pair of Ortho-K contact lenses
A. with the aid of a DMV plunger.
Ch8-11. The removal of an Ortho-K contact lens should be done A. with the aid of a DMV plunger. B. using the scissors method. C. squeezing the lens between the thumb and forefinger. D. using the roll-off method.
C. have them look in the mirror to determine if the lens is actually in place.
Ch8-11. When dispensing a DMV remover to a PK patient, A. instruct them to occlude the fellow eye to make certain the lens is in place before attempting removal. B. caution them to only use it to re-center the lens. C. have them look in the mirror to determine if the lens is actually in place. D. instruct on how to insert the lens as well as remove it with the DMV remover.
B. faint alignment with the use of a Wratten #12 filter.
Ch8-12. The central fit upon evaluation should show A. apical clearance. B. faint alignment with the use of a Wratten #12 filter. C. steep clearance. D. stippling.
B. within two weeks
Ch8-12. The fitter should make an effort to see the patient ______ of the dispensing visit for an evaluation of the cornea and contact lens. A. within three weeks B. within two weeks C. within one month D. within two months
A. Stabilize the movement on the cornea
Ch8-13. What is the purpose of the peripheral curve of the shaping lens? A. Stabilize the movement on the cornea B. Provides more material to assure the proper diameter of the lens C. Allows for tear exchange and metabolic waste D. There is no need for this curve because the lens does not move much on the eye
D. The low plus power allows for the corneal bounce back
Ch8-14. Low plus power is added to the shaping lens for what reason? A. To make the center thicker B. Low plus power is easier to verify C. Alignment fit require plus prescription D. The low plus power allows for the corneal bounce back
A. Pre-teens and teenagers
Ch8-2. ______ are excellent candidates for Orthokeratology. A. Pre-teens and teenagers B. Presbyopes and teenagers C. Pre-teens and those approaching 50 years of age D. Teenagers and those approaching 30 years of age
B. Pseudophakic Corneal Edema
Ch8-2. ______ is the primary reason for patients requiring a penetrating keratoplasty. A. Keratoconus B. Pseudophakic Corneal Edema C. Myopia D. Hyperopia
C. irregular astigmatism.
Ch8-3. The most common indication for contact lens use following PK is A. myopia. B. cataracts. C. irregular astigmatism. D. bullous keratopathy.
B. corneal scar.
Ch8-4. A candidate for corneal reshaping would most likely be excluded if they have A. mild dry eye. B. corneal scar. C. 0.75D against the rule astigmatism. D. myopia of -6.00D.
A. a large difference in refractive errors between the two eyes.
Ch8-4. Anisometropia is A. a large difference in refractive errors between the two eyes. B. an imbalance in eye muscles. C. a contraindication to contact lens wear. D. best managed by custom soft contact lenses.
D. All of the above.
Ch8-5. A thorough pre-fitting interview should include A. diagnosis prior to surgery. B. time since surgery. C. current ocular and systemic medications. D. All of the above.
D. All of the above.
Ch8-5. Patients nearing presbyopic age can be fit A. binocularly with mono-vision. B. binocularly for distance correction. C. one eye corrected for distance. D. All of the above.
A. begins centrally and moves peripherally to the graft-host interface.
Ch8-6. Healing of the graft A. begins centrally and moves peripherally to the graft-host interface. B. begins at the graft-host interface and moves centrally. C. takes less than three months in most cases. D. begins at the limbus and moves to the sclera.
D. the patient exhibits myopia greater than 5.00D.
Ch8-6. If a patient has astigmatism, he/she can be a candidate for Ortho-K except when A. corneal astigmatism is less than 1.50 or less with the rule. B. refractive and corneal astigmatism are nearly the same. C. have 0.75D against-the-rule astigmatism. D. the patient exhibits myopia greater than 5.00D.
B. patient's gender.
Ch8-7. Factors affecting the speed of the healing of the graft-host interface include all of the following except A. patient's age. B. patient's gender. C. individual wound healing factors. D. suturing techniques.
C. Eliminating the myopia
Ch8-7. What would be an advantage to Ortho-K? A. Eliminate the need for any glasses B. Young patients needing good vision for sports C. Eliminating the myopia D. Less care regimen involved than regular contacts
D. increased susceptibility to wound dehiscence.
Ch8-8. Premature suture removal can lead to A. stability of the corneal topography. B. decreased susceptibility to wound dehiscence. C. stability of refractive error. D. increased susceptibility to wound dehiscence.
C. When the lenses are not worn anymore
Ch8-8. When does corneal refractive therapy stop being effective? A. At age 40 B. The visual acuities are 20/30 C. When the lenses are not worn anymore D. At age 50
D. central readings alone will not provide adequate fitting information.
Ch8-9. Keratometry readings are of little value when determining the fit of a post penetrating keratoplasty fit because A. they provide information on the peripheral cornea. B. readings provide adequate power information. C. they can detect topographies such as graft-tilt or graft steepening. D. central readings alone will not provide adequate fitting information.
D. placement and removal instruction.
Ch8-9. The patient can expect the following at each followup appointment except A. visual acuity assessment. B. topography. C. have the lenses cleaned. D. placement and removal instruction.
The answer is C. A back surface toric lens is created with a toric back surface and a spherical front surface. The toric back surface is what causes the two base curves to be found when verifying the lens with a radiuscope. The lensometer reads sphero-cylindrical because the toricity generated on the posterior surface of a back surface toric lens manifests through to the front surface.
If a rigid gas permeable lens is a back surface toric, it will read out on the radiuscope and lensometer as follows: A. One base curve, sphero-cylin drical power B. Two base curves, sphere power only C. Two base curves, sphero-cylindrical power D. One base curve, sphere power only
The answer is A. The three types of ultraviolet radiation are UVA, UVB and UVC. These three types of radiation encompass a range from 100 to 400 nm. UVC is the most harmful of the light rays and is found on the lowest end of the ultraviolet scale (100 to 290 nm). One hundred percent of the light rays below 280 nm are absorbed by the cornea before they pass through to the rest of the optical system. The majority of ultraviolet radiation is absorbed by the crystalline lens, which serves to protect the light sensitive retina.
What are the three types of ultraviolet radiation? A. UVA, UVB, UVC B. UVA,VVA,WVA C. UVl, UV2, UV3 D. Hyper, Hypo, Hyptic