CS 3 - Cycloplegic Refraction

¡Supera tus tareas y exámenes ahora con Quizwiz!

Summary of Dosages - Atropine

0.5% ointment bid x2 d for accommodative Esotropia

Summary of Dosages - Tropicamide

1 gtt 1% Drug of choice for routine dilated exam For cycloplegia: 1 gtt 1% q 5 min - refract in 25 minutes

Summary of Dosages - Cyclopentolate

1 gtt 1% q 5 min x2 Drug of choice for routine cycloplegic exam Refract 30 min after instillation Don't use 2% solution-adverse reactions

Atropine

Absorbed through: Cornea Conjunctiva Nasal Mucosa GI Tract

Cyclopentolate Side Effects

Allergic Reaction

Ocular Reactions

Allergic Reaction (especially lids/conjunctiva) Itchy, red, swollen Atropine>Cyclopentolate>Tropicamide (rare)

Tropicamide Side Effects

Allergic Reactions

Atropine Side Effects

Allergic Reactions (contact dermatitis)

Adverse Reactions

Allergy Unpredictable/unexpected reaction Due to previous sensitizing reaction

Tropicamide Side Effects

Angle Closure

Ocular Reactions

Angle-Closure Glaucoma Precipitation of an acute attack Unlikely Observe Precautions: Assess Hx, Assess chamber depth, advise patient of surgery, check IOP before patient leaves

Cyclopentolate Side Effects

Angle-closure glaucoma

Cycloplegic Efficacy

Atropine 100% Scopolamine 92-96% Cyclopentolate 92% Homatropine 60-80% Tropicamide 60-80%

Cyclopentolate Indications

Children

Clinical Procedures - Instillation - Cap Color

Clear=topical anesthetic Red=mydriatic/cycloplegic agent Green=miotic

Proparicaine Adverse Effects

Conjunctival hyperemia

Proparicaine Allergic Reactions

Contact dermatitis (most common) Neomycin>atropine>proparicaine Periocular swelling Erythema Typical rash

Proparicaine Adverse Effects

Corneal Edema

Proparicaine Adverse Effects

Decreased reflex tearing Blocks afferent loop of reflex tearing

Cycloplegia helps Anterior Segment Inflammation by:

Decreases pain due to iridocyclitis Decreases possibility of posterior synechia Tends to restore permeability of inflamed vessels Decreases cells & flare Decreases clogging of angle

Proparicaine Adverse Effects

Delayed corneal healing

Residual Accommodation - Yasuna's Method

Distance correction in phoropter Add +3.00D OU Occlude one eye Target=0.5M at 33cm Reduce + in 0.25D steps to blur Replace +3.00D add in OU again Add + in 0.25D steps to blur Dioptric difference=residual accommodation

Residual Accommodation - Duane's Method

Distance correction in phoropter Add +3.00D OU Occlude target eye Target=0.5M at 33cm Determine near blur point Determine far blur point Dioptric difference=residual accommodation

General Contraindications

Down syndrome (especially with atropine)

Proparicaine

Duration is 10-20 minutes

Atropine

Duration of adequate cycloplegia: 24 hours

Cyclopentolate

Duration of cycloplegia is 1 day

Tropicamide

Duration of cycloplegia is 6 hours

Atropine

Duration of cycloplegia: 7-12 days

Cyclopentolate

Duration of maximum clycloplegia is 2 hours

Tropicamide

Duration of maximum cycloplegia: 15 minutes for 0.5% 40 minutes for 1.0%

Cyclopentolate

Duration of mydriasis is 1 day

Tropicamide

Duration of mydriasis is 6 hours

Atropine

Duration of mydriasis: 7-10 days

Proparicaine Adverse Effects

Endothelial toxicity If transcorneal portal of entry (a perforation)

Proparicaine Adverse Effects

Epithelial toxicity Increases sloughing rate of epithelial cells Slows healing rate (decreases motility)

General Indications for Cycloplegia

Esotropia - to determine accommodative component Suspected latent hyperopia Suspected pseudomyopia Young children Uncooperative/uncommunicative patients Suspected malingering/hysteria Reduced VA with no detectable pathology Anterior segment inflammation

Atropine Indications

Esotropia in children (especially if less than 4 yo) Try 1% cyclopentolate x2 first If residual ET, then use atropine

Atropine Side Effects

Fatal Dose Adult: 100 mg (200 drops of 1%) Children: 10 mg (20 drops of 1%)

Atropine Contraindications

Glaucoma (COAG or NAG) Narrow Angles Hypersensitivity Iris-Fixated IOL Down Syndrome

Cyclopentolate Contraindications

Glaucoma (COAG or NAG) Narrow angles Hypersensitivity Iris-fixated IOL Down syndrome Children with emotional problems History of seizures

Clinical Procedures - Pre-instillation

History VA Pupils Externals Van Herick test Tonometry

Systemic Reactions

Hot as a hare (fever, inability to sweat) Red as a beet (facial flushing, vasodilation) Dry as a bone (dry skin/mouth, inhibition of exocrine glands) Blind as a bat (Cycloplegia, blurred vision) Mad as a wet hen (Irritability/hallucinations, CNS toxicity)

Adverse Reactions

Hyper-susceptibility (intolerance) Quantitatively different response Greater than normal response Due to biologic variation, disease, or other medications

Adverse Reactions

Idiosyncrasy (genetically determined, abnormal reactivity)

Prescribing Myopes

If wet refraction is equal to or more minus than dry refraction: prescribe dry results

Proparicaine Secondary Adverse Effects

Interference with diagnostic tests: Hypofluorescence of fluorecein Variability in Shrimer testing Reduction of microbial recovery in culturing Preclusion of sequential testing Surface keratopathy

Cycloplegic considerations

Iris Color (darkly pigmented=stronger)

General Contraindications

Iris-fixated IOL

General Contraindications

Known Allergy to drug

Tropicamide Contraindications

Known Hypersensitivity Narrow Angle Glaucoma Narrow Angles Iris-fixated IOL

Suspected Pseudomyopia

Low myope on subjective ref. NP symptoms VA fluctuation Acc. hysteresis (blur on looking up) Static more plus than subjective NRA > PRA Acc. amp. low for age

Total Hyperopia

Manifest hyperopia + Latent hyperopia

Cyclopentolate

Maximum cyclopegia after 30-60 minutes

Atropine

Maximum cycloplegia after 1-3 hours

Tropicamide

Maximum cycloplegia after 30-45 minutes

Tropicamide

Maximum mydriasis after 20-35 minutes

Atropine

Maximum mydriasis after 30-40 minutes

Cyclopentolate

Maximum mydriasis after 30-60 minutes

Proparicaine Adverse Effects

Microbial contamination

General Contraindications

Narrow angles History of Narrow Angle Glaucoma

Suspected latent hyperopia

Nearpoint complaints EP at distance Miotic pupils High FCC finding Decreased accommodative amplitude for age Static refraction yields more plus than subjective NRA > +2.50D

Cylcoplegic Disadvantages

Not always complete Not always equal Not always properly timed Alters AC/A Decreases depth of focus Increases aberrations Can make retinoscopy difficult (concentrate on 4 mm in center of pupil) Inconvenience to pt Blurred vision Photophobia Potential adverse effects Toxic Allergic

Proparicaine

Onset is 10-20 seconds

Cycloplegia

Paralysis of accommodation Due to paralysis of the ciliary muscle

Proparicaine

Patient education! Do not rub eyes for next 30 minutes

Cycloplegic considerations

Patients age (younger=greater accommodative amplitude=stronger amplitude)

Atropine

Potent long-acting mydriatic/cycloplegic

Atropine Side Effects

Precipitation of acute-angle closure Glaucoma

Topical Anesthetia - Proparacaine

Prevents stinging Decreases blink rate & tearing (allows prolonged contact time) Roughens corneal epithelium (increases drug penetration)

Proparicaine Adverse Effects

Punctate Keratitis

Cyclopentolate

Rapidly-acting mydriatic/cyclopegic

Tropicamide

Rapidly-acting, short duration, mydriatic/cycloplegic

Proparicaine Adverse Effects

Reduced blink rate Increases evaporation

Tropicamide Side Effects

Safest mydriatic/cycloplegic for patients with: Hypertension Angina Cardiovascular disease

Cycloplegic considerations

Stabismus evaluation (needs greater potency)

Residual Accommodation - Pascal's Method

Static at Distance Static at retinoscope plane Dioptric difference = residual accommodation

Proparicaine Allergic Reactions

Stevens-Johnson Syndrome Skin/mucous membrane disorder Acute phase: fever, URI, mucopurulent conjunctiva Chronic phase: scarring stage

Proparicaine Adverse Effects

Stinging/lacrimation

Cyclopentolate Indications

Suspected latent hyperopia

Cyclopentolate Side Effects

Systemic Reactions Flushing, Fever, Drowsiness (especially in children)

Proparicaine Adverse Effects

Tear film instability Disrupts surface microvilli of epithelial cells, decreases mucous adherence

Cylcoplegic considerations

Therapeutic use (duration proportional to severity of inflammation)

Cycloplegic considerations

Timing (occupational/studying needs=needs short acting)

Atropine Side Effects

Toxic Reactions

Adverse Reactions

Toxicity (Poisoning)

Cyclopentolate Side Effects

Transient IOP elevation

Tropicamide Side Effects

Transient IOP elevation <5mmHg=insignificant clinically

Ocular Reactions

Transient IOP elevation Decreased aqueous outflow, especially occurs in COAG pts, check IOP before patient leaves

Atropine Side Effects

Transient IOP elevation (especially in Chronic Open Angle Glaucoma)

Tropicamide Side Effects

Transient Stinging

Cyclopentolate Side Effects

Transient psychotic reaction Hallucinations Disorientation Restlessness Ataxia Incoherent speech

Cyclopentolate Side Effects

Transient stinging/burning/discomfort

Proparicaine

Use 1 gtt (drop) of 0.5% solution

Tropicamide Side Effects

Visual hallucinations

Tropicamide Indications

Wide dilation (great for BIO)

Facultative Hyperopia

amount of hyperopia that can be compensated for by the patients accommodation

Absolute Hyperopia

amount of hyperopia that cannot be compensated for by the patients accommodation Present if hyperopia is greater than accommodative amplitude

Manifest Hyperopia

amount of hyperopia that may be measured by relaxation of accommodation by plus lenses

Latent Hyperopia

amount of total hyperopia compensated for by the residual tonicity of the ciliary muscle Not equal to facultative hyperopia May be revealed by cycloplegia Cannot be relaxed voluntarily or with plus lenses during dry refraction


Conjuntos de estudio relacionados

4 Types of Readiness to Learn (PEEK)

View Set

World AP Final Exam (Mock STAAR)

View Set

Chapter 14.3 During the Interview Aplia Assignment

View Set

financial accounting tophat chp 12b

View Set

Windows Server 2016 Identity: Active Directory Maintenance & Recovery

View Set

Cold War, Space Race, and Moon Landing

View Set

ch 29 Child With a Genitourinary Condition

View Set

The Great Hadeeth of Angel Jibreel

View Set

chapter 15 fetal assessment during labor

View Set