Chapter 5 - Disorders of the Eye and Ear.

Inflammatory infections of the hair follicles of the eyelid called hordeolum (styes) are caused by...

- staphylococcal infection.

Placement of sharp objects into the ear canal, an explosion, a severe middle ear infection, or a blow to the ear could result in ...

a ruptured tympanic membrane. *The four most common causes of a ruptured eardrum are insertion of sharp objects into the ear canal, a nearby explosion (including lightning strikes), a severe middle ear infection, and a blow to the ear. A ruptured eardrum also can occur as a result of a fractured skull. The eardrum occasionally ruptures spontaneously.

The wet form of macular degeneration is described as...

a serious form that can result in damage to the retina, resulting in loss of central vision. *The presence of abnormal fragile and hemorrhage-prone blood vessels can develop behind the macula and convert the disease to its wet form. Hemorrhage may occur when these abnormal vessels break and damage the retina. The result is loss of central vision.

Drug therapy used in the treatment of mastoiditis includes...

antibiotic or sulfonamide therapy. *The treatment is based on the results of the sensitivity studies. Antibiotic or sulfonamide therapy is prescribed. Mastoiditis not responding to this treatment necessitates a surgical procedure, called simple mastoidectomy, to prevent further complications and to preserve hearing. A radical mastoidectomy may be needed for chronic mastoiditis.

Which of the following statement(s) is/are true about nystagmus? - It is usually treated with warm compresses. - it is also known as strabismus. - it necessitates a complete neurologic evaluation when acquired. - all of the statements above are true.

- It necessitates a complete neurologic evaluation when acquired. *Any repetitive or involuntary movement of one or both eyes is a sign of nystagmus. Acquired nystagmus always necessitates a complete neurologic evaluation.

Diagnostic findings for benign paroxysmal positional vertigo (BPPV) may include ... - the sensation of the room spinning and lack of coordination. - nystagmus. - decreased hearing. - all of the above.

- all of the above. *Diagnosis is made from the history and examination. In addition to the false sensation of the room spinning or the patient spinning, nystagmus (involuntary eye movements) may be present. An audiogram or other means of hearing testing are used to determine the patient's level of hearing. Many times the hearing will be decreased. Lack of coordination may be detected, along with weakness and unsteadiness in the legs. Additional testing to rule out central nervous system involvement may include a computed tomography (CT) scan of the head, magnetic resonance imaging (MRI) scan of the head, or a magnetic resonance angiogram scan of the brain's blood vessels. Another test is caloric stimulation in which, by means of a syringe, cool water followed by warm water is gently flushed against the eardrum to test eye reflexes. In a normal test, no abnormal eye movements will be observed. During the test, BPPV can be detected if the eyes have sustained involuntary movement from side to side. Blood tests may be ordered to rule out other disease conditions.

Macular degeneration is ... True or False?

- caused by progressive deterioration in the macula of the retina. - usually related to aging. ^ both of the above. *Age-related macular degeneration (AMD) is the most common cause of blindness among white persons in the United States. Macular degeneration is often considered to be age related. The result is loss of central vision. No cure is known, and the success of treatment has been limited.

Causes of ruptured tympanic membrane are ...

- infection. - blow to the ear. - nearby explosion. ^ all of the above. *Any type of tear or injury to the eardrum causes a breach in the integrity of the membrane. This may be the result of pressure, force, or insult from the exterior aspect, or it may be caused by increased pressure within the middle ear.

Treatment of refractive errors of the eye might include...

- laser surgery. - contact lenses. - eyeglasses... ^ all of the above. *Correcting refractive errors involves fitting the patient with artificial lenses in the form of eyeglasses or contact lenses or performing corrective surgery. Radial keratotomy, a surgical procedure used to reshape the eye, has been replaced by laser surgery, which results in more precise visual correction and has fewer complications. The following refractive surgical procedures can be done to correct myopia, hyperopia, and astigmatism: laser-assisted in-situ keratomileusis (LASIK), astigmatic keratotomy, photorefractive keratotomy, laser thermal keratoplasty, conductive keratoplasty, and intraocular contact lenses (lenses permanently placed in the eyes).

The cause of sensorineural deafness, also referred to as occupational hearing loss, includes...

- loud noise. - the aging process. - the side effects of certain medication. ^all of the above. *The cause of sensorineural hearing loss is nerve failure or damage to the cochlea or the auditory nerve (VIII vestibulocochlear cranial nerve). This can be the result of the aging process (see Table 5-3); however, loud music, machinery noise, or sometimes the side effects of medications - including aminoglycosides (tobramycin), loop diuretics, aspirin, or antimetabolites (methotrexate) - can cause such damage at any age (see Figure 5-35, A and B). Other causes include mumps, measles, syphilis, meningitis, suppurative labyrinthitis, or viral infections. In addition, physical trauma with a fracture of the temporal bone may be a causative factor.

Symptoms of neoplasms of the ear commonly include

- progressive hearing loss and discharge from the ear. - a visible mass or lesion. - facial paralysis. *Signs and symptoms of these neoplasms commonly include progressive hearing loss, chronic otic discharge, a visible mass or lesion on ear examination, loss of equilibrium, and tinnitus. Some cancers, such as squamous cell carcinoma of the middle ear, are quite painful. Glomus tumors cause a pulsatile tinnitus, that is, hearing a pulsing sound in the ear that has the tumor, as a result of the tumor pressing on the bones of hearing.

Which statement(s) is/are true regarding adult-onset macular degeneration (AMD)? - Early evidence of AMD, such as tiny drusen can be seen during a routine eye exam by an ophthalmologist. - Patients with AMD may report seeing wavy lines when looking at lines that are straight. - With progression of AMD, reading and activities requiring sharp vision become impossible. - All of the above are true.

All of the above are true. *The condition is usually painless, develops slowly, and does not affect the peripheral vision. In most cases, both eyes are affected, either at the same time or one right after the other. As the condition worsens, reading and activities that require sharp vision become impossible. Eventually, the central vision may disappear altogether. AMD is the most common cause of blindness among white persons in the United States.

Treatment of BPPV includes ...

Antihistamines, anticholinergics and benzodiazepines. *Antihistamines [Antivert, Dramamine], anticholinergics [Scopolamine], and benzodiazepines [Compazine] may be prescribed to reduce symptoms of positional vertigo. Exercises in which the individual repeatedly turns the head from side to side may also be helpful.

A cloudy or opaque area in the normally clear lens of the eye is called

Cataract. *The most common cause of cataracts is opacification of the lens caused by the aging process, and the condition is present in about 50% of persons over age 75 in the United States. They also may be congenital or may result from ocular trauma; drug toxicity (prolonged high-dose corticosteroid administration); systemic disease, such as diabetes mellitus; or a complication of other ocular diseases. Long-term, unprotected exposure to sunlight is considered causative as well. Cataracts often have a familial occurrence; however, they also are a common condition in the general population.

Ototoxicity caused by drugs or chemicals affects the ________ nerve.

Eighth *Ototoxicity occurs when a drug or chemical causes damage to the eighth cranial (acoustic) nerve or to the inner ear, resulting in temporary or permanent hearing loss or disturbances in balance.

Blepharoptosis can be ectropion or entropion. True or False?

False. *Blepharoptosis, also called ptosis, is a permanent drooping of the upper eyelid, such that it partially or completely covers the eye. Blepharoptosis usually affects one eye, but both can be involved. In the case of entropion, the eyelid margins (more often the margin of just the lower lid) turn inward, causing the lashes to rub the conjunctiva. Ectropion is a condition in which the lower eyelid everts from the eyeball, and the exposed surface of the eyeball and the lining of the eyelid become dry and irritated.

Cochlear implants restore normal hearing. True or False?

False. *Individuals who experience severe sensorineural hearing loss that is not helped by hearing aids may have partial hearing restored by means of cochlear implants. Cochlear implants are electronic devices that use minute electrical currents to stimulate the auditory nerve and help the currents travel to the auditory cortex to be perceived as sound.

Sensorineural hearing loss has noticeable onset. True or False?

False. *Sensorineural hearing loss usually has an insidious onset. Many times the hearing loss is detected during a routine medical examination or preemployment screening. An abrupt onset of hearing loss is possible after sudden exposure to a loud explosive type of noise or nearby lightning strike.

The major risk with having a ruptured eardrum is an infection in the inner ear. True or False?

False. *Symptoms of a ruptured tympanic membrane (eardrum) are usually slight pain and partial loss of hearing and may include a slight discharge or bleeding from the ear. Buzzing in the ear and/or facial weakness or dizziness may be experienced. When an infectious process is involved, the drainage is usually purulent in nature. These symptoms may last only a few hours The major risk is that an infection may develop in the middle ear.

The ear's only function is hearing. True or False?

False. *the ear is the organ of balance and the organ of hearing.

A major cause of blindness in the United States is ...

Glaucoma. *damage to the optic nerve in the presence of elevated IOP. It is more common in patients older than 60 years of age; however, it can occur at any age. Several different pathologic causes and abnormalities in fluid drainage lead to glaucoma. Early treatment of glaucoma is essential; if not treated promptly, the disease can lead to blindness because any vision lost as a result of the disease generally cannot be regained.

Conjunctivitis can be caused by ...

Infection, irritation, allergies, or chemicals. *Conjunctivitis can be caused by infection, most commonly viral or bacterial, and also by irritation resulting from allergies or chemicals. Infections often are transmitted when contaminated fingers, washcloths, or towels touch the eyes.

Blepharitis is defined as...

Inflammation of the margins of the eyelids involving hair follicles and glands. *causes persistent redness and crusting on and around the eyelids. Visual examination of the eyelids and the presence of collarettes - tiny scales can determine the presence of staphylococci.

Which of the following statements is true about chronic open-angle glaucoma?

It is the most treatable cause of blindness. *Chronic open-angle glaucoma, a silent disease, is the most common form of glaucoma and is the most treatable cause of blindness. Patients can have open-angle glaucoma for a significant period of time before symptoms appear. By the time symptoms do appear, considerable damage usually has occurred. If chronic open-angle glaucoma goes untreated, the patient experiences characteristic loss of vision. The central vision may remain clear for a considerable period of time. However, if the condition progresses, the central vision is also lost, causing complete blindness. The best way to detect glaucoma is by having periodic routine ophthalmic examinations, which include IOP readings and optic nerve evaluations.

Infection or inflammation in the semicircular canals is called...

Labyrinthitis. *The labyrinth is a group of three fluid-filled chambers (the semicircular canals) in the inner ear that control balance (see Figure 5-31). Inflammation or infection of these chambers is called labyrinthitis.

A chronic disease of the inner ear marked by a recurring syndrome of vertigo, tinnitus, progressive hearing loss, and a sensation of pressure in the ear is called...

Meniere's disease. *Ménière's disease is marked by a recurring syndrome of vertigo, tinnitus, progressive hearing loss, and a sensation of fullness or pressure in the affected ear. Symptoms have a sudden onset. Nausea, vomiting, tinnitus, sweating, and loss of balance can follow an acute attack of vertigo. Some individuals may be subjected to nystagmus, whereas others may experience an unusual sensitivity to noises (hyperacusis). These attacks can last from a few hours to several days and may become increasingly serious with each recurrence. Ménière's disease usually affects just one ear, but both ears may become involved eventually. The disease usually manifests in individuals between 40 and 50 years of age.

Ankylosing of the stapes is called ...

Otosclerosis. *Otosclerosis, an abnormal bone growth in the middle ear, primarily affects the stapes, the third bone or ossicle of the middle ear, as the individual ages. Movement of the ossicles is impaired, which causes diminished conduction of sound waves and resulting hearing loss (see Figure 5-30). With this condition, an abnormal growth of spongy bone forms around the oval window, causing ankylosis of the stapes. Ankylosis produces conductive deafness because the ossicles cannot conduct the sound vibrations as they enter the ear. Symptoms of otosclerosis are tinnitus and a gradual hearing loss of low or soft sounds, which may be unilateral at first, but usually affects both ears at some point. Patients usually report not being able to hear as well with the affected ear when talking on the telephone. Relatives may notice that patients turn their heads to hear well. Otosclerosis is a young person's disease, with onset usually beginning after puberty and before 35 years of age.

The sensor receptive cells in the retina that function best in dim light and enable night vision are the...

Rods. *The retina is a light-sensitive layer made up of photoreceptive cells called rods and cones. Within the rods and cones, the image initiates a chemical reaction and sends messages through the nerve fiber layer of the retina to the optic nerve.

Labyrinthitis is an inflammation of the ...

Semicircular canal. *The inner ear contains two membrane-lined chambers, each filled with fluid, called the cochlea and the labyrinth. The cochlea contains tiny hairs that change the sound waves in the fluid into nerve impulses, which then are transmitted to the brain via the auditory nerve. The labyrinth is responsible for maintaining balance. It consists of three connected tubes bent into half circles, called the semicircular canals. Their function is to detect movement of the head and relay this information to the brain.

Treatment of swimmer's ear includes...

Thoroughly cleaning and drying the ear after swimming. *It is important for the ear canal to be kept clean and to be dried after swimming. Antibiotic or steroid eardrops and systemic antibiotics may be prescribed, depending on the severity of the condition. Swimmer's ear tends to recur and can become chronic for those with repeated exposure to water as in swimming.

A cholesteatoma and mastoiditis can both be the result of a neglected otitis media. True or False?

True, *This condition often begins to develop in infancy or it may be the result of chronic ear infection. The eustachian tube from the middle ear to the pharynx either fails to open properly or becomes blocked with material from recurring middle ear infections (see "otitis media" section). As a result, this normally air-filled chamber develops a weak vacuum, causing the eardrum to become retracted. This forms the pocket in the eardrum that allows the cholesteatoma to develop. Acute mastoiditis is the result of neglected acute otitis media. Streptococcus is the usual causative organism, but certain pneumococci and Staphylococcus aureus may also be involved. Chronic mastoiditis, necessitating radical or modified radical mastoidectomy, is associated with cholesteatoma.

Sensorineural hearing loss that is caused by damage to the cochlea is irreversible; therefore, prevention is essential. True or False?

True.

Symptoms of corneal abrasion or ulcer include pain, redness, tearing and sometimes visual impairment. True or False?

True. * A corneal abrasion is the painful loss of surface epithelium or outer layer of the cornea. The patient with corneal abrasion may experience significant persistent pain in the eye - prompt medical care needed.

Audiograms are used to diagnose otosclerosis... True or False?

True. *A diagnosis of otosclerosis is made by the physician using an audiogram, the patient history, and otoscopy. The audiogram will show a moderate to severe hearing loss, especially for loss in the low range.

Benign tumors of the ears include acoustic neuromas. True or False?

True. *Benign tumors of the ear include acoustic neuromas, facial neuromas, and glomus tumors. An acoustic neuroma arises from the eighth cranial nerve, whereas a facial neuroma is a tumor of the facial nerve. These tumors put pressure on the nerve fibers as they expand, causing hearing loss or facial paralysis, respectively, among other symptoms. Glomus tumors are the most common tumors of the middle ear and arise from the glomus bodies (tiny structures that serve as baroreceptors) (see Figure 5-36).

Diabetic retinopathy occurs most often in those with diabetes who do not control their blood glucose levels. True or False?

True. *Diabetic retinopathy usually occurs about 8-10 years after the onset of diabetes mellitus. It occurs most often in those with diabetes who do not control their blood glucose levels, but all persons with diabetes are susceptible.

Certain medications can cause ototoxicity... True or False?

True. *Drugs that can cause ototoxicity include salicylates (aspirin and aspirin-containing products); nonsteroidal antiinflammatory drugs; certain antibiotics (aminoglycosides, erythromycin, vancomycin); loop diuretics (furosemide [Lasix], bumetanide [Bumex], ethacrynic acid [Edecrin]); chemotherapeutic agents (cisplatin, vincristine, vinblastine); quinines (quinidine and quinine); and heavy metals, including mercury and lead.

Chronic open-end glaucoma results from a malfunction of the drainage system, which causes IOP to be raised. True or False?

True. *In chronic open-angle glaucoma, a block at the level of the trabecular meshwork impairs aqueous humor reabsorption. Chronic open-angle glaucoma can occur secondary to trauma, even years later. Overuse of topical steroids also can cause the condition. If the IOP is somewhat elevated or the optic nerve shows signs of enlarging, glaucoma needs to be considered as a possibility.

Infants and young children should be evaluated for leukokoria (white pupil) and strabismus at well child exams and referred urgently to an ophthalmologist if noted. True or False?

True. *Strabismus should be treated as soon as possible. Early intervention is the key. Corrective glasses, treatment to minimize or prevent amblyopia, or surgery to restore the eye muscle balance may be used in the course of the treatment. Patients reporting visible lesions around or "in" the eye, or those experiencing any unusual appearance or movement of the eye(s) with or without pain, need a timely appointment for a medical evaluation and an ophthalmic examination.

Lightning strikes may cause a ruptured tympanic membrane. True or False?

True. *The four most common causes of a ruptured eardrum are insertion of sharp objects into the ear canal, a nearby explosion (including lightning strikes), a severe middle ear infection, and a blow to the ear. A ruptured eardrum can also occur as a result of a fractured skull. The eardrum occasionally ruptures spontaneously.

The labyrinth is responsible for maintaining balance. True or False?

True. *The inner ear contains two membrane-lined chambers, each filled with fluid, called the cochlea and the labyrinth. The cochlea contains tiny hairs that change the sound waves in the fluid into nerve impulses, which then are transmitted to the brain via the auditory nerve. The labyrinth is responsible for maintaining balance. It consists of three connected tubes bent into half circles, called the semicircular canals. Their function is to detect movement of the head and relay this information to the brain.

The middle ear is normally air-filled. True or False?

True. *The middle section is filled with air and contains the tympanic membrane and three ossicles (tiny bones) called the malleus (hammer), the incus (anvil), and the stapes (stirrup). Also in the middle ear is a canal, called the eustachian tube, which leads to a cavity (the pharynx) at the back of the nose. At the innermost region of the middle ear is the oval window, the opening to the inner ear. The middle ear receives the sound waves from the vibrating eardrum and relays them along the three bones to the oval window (see Figure 5-19).

The most common tumor of the eye is cancer that has metastasized to the eye. True or False?

True. *The most common sites of origin are the lung in men and the breast in women, but many other types of cancer also are known to metastasize to the eye.

The internal lens of the eye is elastic and, therefore can focus images both near and far. True or False?

True. *Refractive errors are the most common cause for diminished visual acuity. Refractive errors that result in the eye being unable to focus light effectively on the retina are identified as hyperopia, myopia, astigmatism, and presbyopia.

The only treatment that cures otosclerosis is a surgical procedure called stapedectomy. True or False?

True. *The only treatment that cures otosclerosis is a surgical procedure called a stapedectomy. A stapedectomy involves the removal of the diseased stapes and replacement with a prosthesis. The composition of the prosthesis may be metal or a ceramic or plastic material. Use of a ceramic or plastic is likely because these materials facilitate visualization by MRI for the purpose of diagnosing and because of the inability to perform an accurate test of the patient's hearing if the prosthesis is made of metal. If the condition is bilateral, only one ear is operated on at a time so the success of the procedure can be evaluated. Generally, hearing improves soon after the surgery. A recent procedure, a stapedotomy, is performed with a laser creating a hole in the stapes permitting placement of a prosthetic device. If surgery is not an option for the patient, a hearing aid can be tried.

A defect in the _____ results in difficulty in visual detection of color and fine detail.

cones *The retina is a light-sensitive layer made up of photoreceptive cells called rods and cones. The rods function best in dim light, thereby enabling night vision, whereas the cones function in bright light and also detect color and fine detail. Within the rods and cones, the image initiates a chemical reaction and sends messages through the nerve fiber layer of the retina to the optic nerve.

An inflammation of the thin, transparent membrane covering the visible portion of the sclera and lining the inside of the eyelids results in ...

conjunctivitis. *can be caused by infection, most commonly viral or bacterial, and also by irritation resulting from allergies or chemicals. Infections often are transmitted when contaminated fingers, washcloths, or towels touch the eyes. Conjunctivitis can also be produced through sexual contact with someone who has a sexually transmitted disease.

Hyperopia, myopia, presbyopia are refractive errors that result when the ...

eye is unable to focus light effectively. *Hyperopia (farsightedness) occurs when light that enters the eye is focused behind the retina rather than on the retina. Myopia (nearsightedness) is the result of light rays entering the eye being focused in front of the retina, causing blurred vision. Presbyopia is the inability of the internal lens of the eye to focus on near objects due to loss of elasticity of the lens.

The insertion of a myringotomy - tympanostomy tube as a treatment for otitis media is called ...

myringotomy. *Analgesics and decongestants may be ordered to provide pain relief and to promote drainage in both types of otitis media. Oral or topical antibiotics are ordered for cases of suppurative otitis media. In severe cases, or in patients who fail to respond to medical treatment, surgical evacuation of the fluid (myringotomy) is necessary to prevent permanent hearing loss and the possible development of mastoiditis (see "mastoiditis" section) or a cholesteatoma (see "cholesteatoma" section). To keep the middle ear filled with air and to prevent fluid from accumulating, myringotomy (tympanoplasty) tubes (see Figure 5-28) may need to be inserted after the myringotomy (see Figure 5-29). Diagnosis and treatment of any allergic response involved is necessary. Removal of hypertrophic adenoids is a therapeutic measure.

Early symptoms of retinal detachment consist of ...

new floaters and light flashes. *A retinal detachment usually begins with a tear in the retina. Fluid then leaks under the retina and separates it from the choroid. After the retina is separated from the choroid, that portion of the retina no longer functions visually. As the retina continues to detach, more and more vision is lost.