Definition
A.Clear vision occurs when the cornea and the crystalline lens bend (refract) light appropriately onto the retina. Refractive errors occur when any component of the optical system malfunctions. Refraction errors are common and correctable. Refractive errors include ametropia (including myopia, hyperopia, astigmatism) and presbyopia.
Incidence
A.Refractive disorders affect more than one third of people 40 years or older. Myopia and astigmatism are the two most prevalent refractive disorders. Myopia (nearsightedness) is more common in Caucasians and Asians. Astigmatism and presbyopia increase with aging.
Pathogenesis
A.Emmetropia (normal refraction) begins in childhood and continues into early adulthood. The etiology of poorly developed emmetropization is unknown.
Predisposing Factors
A.Myopia:
1.Genetic predisposition.
2.Reading for long periods.
3.Medications (sulfonamides, diuretics, and cholinergics), the adverse effects of which are reversible with discontinuing medication.
4.Diabetes.
5.Trauma.
6.Excessive accommodation.
7.Cataracts.
8.Older maternal age at birth or maternal smoking.
B.Hyperopia:
1.Trauma.
2.Anticholinergic medications.
Common Complaints
A.Fear of driving or performing usual, common activities due to decreased visual acuity.
Potential Complications
A.Motor vehicle accidents.
B.Increased risk of falls and hip fractures.
C.Isolation due to fear of leaving familiar environment.
Subjective Data
A.Review the onset, duration, and course of symptoms.
B.Was the change in vision sudden or gradual?
C.Determine family history of refractive disorders.
D.Review history of eye disorders and previous eye surgeries or treatments.
E.Review date of last eye exam, including dilation.
F.Review past medical history, including current medications and history of diabetes.
G.Determine if patient has used over-the-counter (OTC) corrective lenses and duration of use.
H.Has there been a change in vision associated with headaches?
I.Ask about the amount of up-close work, including reading, computer use, factory assembly, and sewing.
J.Determine the amount of change in activities of daily living (ADLs) due to visual impairment.
K.Ask about perceived safety concerns and history of falls.
Physical Examination
A.Vital signs, including blood pressure.
B.Inspect:
1.Symmetry of eyes and obvious deformities.
2.Pupil symmetry and response to light and accommodation.
3.Assess fields of vision and extraocular movements.
4.Funduscopic assessment.
5.Snellen and Rosenbaum screening.
6.Observe for entropion or ectropion.
7.Observe for pterygium.
Diagnostics
A.Phoropter (performed by an optometrist or ophthalmologist).
Differential Diagnosis
A.Cranial nerve dysfunction (CN II, III, VI).
B.Transient ischemic attack (TIA)/cerebrovascular accident (CVA).
C.Trauma (if sudden unilateral reduction in acuity).
D.Glaucoma.
E.Space-occupying intracranial lesion.
F.MD.
G.Diabetic retinopathy.
H.Cataracts.
Plan
A.General interventions:
1.A referral to an eye specialist for formal diagnosis and prescription for corrective lenses.
2.Discuss eye health, including routine eye exams and prevention of injury.
B.Patient teaching:
1.Importance of routine eye exam.
2.Importance of control of blood sugars if diabetic and blood pressure if hypertensive.
3.Importance of eye protection, including sunglasses.
Consultation/Referral
A.Referral to an eye specialist is required for accurate diagnosis following initial eye screening.
Individual Considerations
A.Adults:
1.Refraction errors are more common with aging, especially myopia, presbyopia, and astigmatism. At 40 years of age, patients should expect presbyopic changes.
2.Diabetic retinopathy, though not a refractive error, is a leading cause of blindness. Patients should receive an annual ophthalmic exam.
3.Eye exams are covered under certain circumstances by Medicare. Patients can receive up-to-date coverage information at Medicare.gov.
B.Geriatrics:
1.Safe driving—age-related vision changes to evaluate and discuss with older adults ≥60 years old:
a.Ability to see road sign clearly decreases
b.The vehicle’s instrument panel becomes blurry and it is difficult to quickly adjust from road to panel.
c.Challenges in judging distances
d.Color perception changes.
e.Night vision ability decreases.
f.Pain and difficulty adjusting to sunlight/headlights.
g.Peripheral vision loss.
2.Avoid wearing eyeglasses or sunglasses with wide frames or side-arm temples that could
restrict vision.
3.Suggest handheld or stand magnifiers when viewing labels or doing tasks such as sewing, puzzles, nail hygiene, and so on. Consider video magnification for computers/monitors. Avoid overuse of eyes, causing tired eyes.
Consider using talking timepieces, audio books, and apps that read aloud Internet news and social media comments.
4.Allow the geriatric patients to express feelings of vision loss and assist with eyesight solutions to assure safety and quality of life.