Cataracts
Jill C. Cash and Mellisa A. Hall
Definition
A.A cataract, an opacity of the crystalline lens of the eye, causes progressive, painless loss of vision (functional impairment). Presenile and senile cataract formation is painless and progresses throughout months and years. Cataracts are frequently associated with intraocular inflammation and glaucoma.
Incidence
A.Cataracts are the most common cause of blindness in the world.
B.95% of people older than age 60 have cataracts without visual disturbance.
C.50% of people older than age 75 have significant visual loss due to cataracts.
Pathogenesis
A.Age-related changes of the lens of the eye result from protein accumulation, which produces a fibrous thickened lens that obscures vision.
Predisposing Factors
A.Age.
B.Trauma.
C.Medications (e.g., topical or systemic steroids, major tranquilizers, or some diuretics).
D.Medical diseases (e.g., diabetes mellitus, metabolic syndrome, Wilson’s disease, hypoparathyroidism, glaucoma, congenital rubella syndrome, chronic anteri, or uveitis).
E.Chronic exposure to ultraviolet (UV) B light (including sunlight).
F.Down syndrome.
G.Low antioxidant vitamin use.
H.Alcohol use.
I.Smoking.
J.Lower educational levels.
K.Poor nutrition and sedentary lifestyle.
L.Lead exposure.
Common Complaints
A.Decreased vision, including reading road signs or small print.
B.Blurred or foggy vision, ghost
images.
C.Inability to drive at night.
Other Signs and Symptoms
A.Initial visual event can be a shift toward nearsightedness.
B.Visual impairment can be more marked at distances, with abnormal visual acuity exams.
C.Severe difficulty with glare.
D.Altered color perception.
E.Frequent falls or injuries.
Subjective Data
A.Review the onset, course, and duration of visual changes, including altered day or night vision and nearsighted versus farsighted vision. Rule out diplopia or hemianopia.
B.Assess whether involvement is in one or both eyes.
C.Determine what improves vision—use of glasses or use of extra light.
D.Review the patient’s medical history and current medications.
E.Review the patient’s history for traumatic injury.
F.Discuss the patient’s occupation and leisure activities to determine exposure to UV rays.
G.Review lifestyle choices that would identify risk of cataract formation.
Physical Examination
A.Inspect:
1.Conduct a funduscopic examination:
a.Check red reflex and opacity:
i.A bright red reflex is seen in the normal eye:
ii.Cataract formation is seen by the disruption of the red reflex.
iii.Lens opacities appear as dark areas against the background of the red-orange reflex.
b.Examine color of opacity. For brunescent cataracts, the nucleus acquires a yellow–brown coloration and becomes progressively more opaque.
c.Check retinal abnormalities, hemorrhage, scarring, and drusen (small yellow deposits).
d.Examine extraocular movements and papillary reactivity.
Diagnostic Tests
A.Perform visual acuity exam.
B.Perform peripheral vision exam.
C.Perform slit-lamp exam to determine the exact location and type of cataract.
Differential Diagnoses
A.Cataracts.
B.Glaucoma.
C.Age-related macular degeneration (MD). MD causes vision loss that is symptomatically similar to cataracts.
D.Diabetic retinopathy.
E.Temporal arteritis.
F.Cerebral vascular accident.
G.Central nervous system (CNS) lesions or neurodegenerative conditions.
Plan
A.General interventions:
1.Monitor the patient for increased interference of visual impairment on his or her lifestyle.
2.Cataracts do not need to be removed unless there is impairment of normal, everyday activities.
3.Surgery is the definitive treatment; however, modification of glasses may improve vision adequately to defer surgery. Contact lenses are optically superior to glasses.
B.Patient teaching:
1.Prevention is important. Teach the patient to use protective eyewear to prevent trauma and sun exposure.
2.Discuss modifiable lifestyle behaviors that increase the risk of cataract formation.
3.Wear a hat with a visor to protect eyes when outdoors.
4.Vitamins: Lutein and zeaxanthin are associated with reduced cataract formation in elderly females.
5.Patients may not be aware of Medicare coverage for surgical removal. Referring them to Medicare.gov will help them understand costs of surgical intervention.
Follow-Up
A.Surgical removal is indicated if the visual disturbance is interfering with the patient’s life, such as causing falls or prohibiting reading.
Consultation/Referral
A.Refer patient for ophthalmologic consultation.
B.Patients should be followed by an optometrist or an ophthalmologist to monitor the cataract for increased size and progressive visual impairment.
C.Contact a social worker or community resources as needed.
Individual Considerations
A.Adults:
1.Cataracts are most commonly seen after the age of 60.
2.Patients complaining of visual disturbance should be screened for cataracts.
B.Geriatrics:
1.More than half of Americans ≥80 years old have cataracts or have had cataract surgery. Older adult cataracts tend to present as a yellow-brown color on the lens. Patients may report a problem with identifying blues, blacks, and purples. Other complaints include cloudy/blurry vision, faded colors, glare, halo around lights (home appliances or headlights), poor night vision, and double/multiple images.
2.After 60 years of age, implement a comprehensive dilated eye exam at least once every 2 years.
3.Interventions for geriatrics include the following:
a.Reduction of UV light exposure. Encourage older adults to wear sunglasses and wide brim hats.
b.Smoking cessation and decrease/avoid alcohol use.
c.Surgery—diagnostic preoperative indications for geriatrics:
i.ECG for patients with heart disease to determine stability
ii.Potassium and creatinine levels for patients on diuretics (renal function).
iii.Glucose trends during stress/infections with diabetics in order to prepare any short-term medicine changes.
iv.Close monitoring for patients taking scheduled anticoagulant/antiplatelet medications.
4.Secondary cataracts may develop after long-term steroid use. Be sure to monitor patients who have chronic obstructive pulmonary disease (COPD) or rheumatoid arthritis (RA)/autoimmune disorders that have been taking daily steroids ≥ one year.