-IBIS-1.5.0-
tx
eyes/ears/nose/throat
cataract
diagnoses
definition and etiology
definition:
Congenital or acquired opacity in the lens of the eye causing a gradual loss of vision.
etiology: They may be developmental or degenerative.
Developmental cataracts include congenital cataracts, which follow diseases like rubella, herpes simplex, cytomegalic inclusion disease, and syphilis, as well as nutritional or toxic factors. They may also manifest as a result of inherited metabolic diseases like galactosemia, Marfan's syndrome, Down's syndrome etc.
Degenerative cataracts are related to aging (senile cataracts), trauma, drugs (esp. corticosteroids), radiation or infrared exposure, ocular disease including uveitis, and metabolic disorders (diabetes, hypoparathyroidism).
Cataracts are the leading cause of decreased vision and blindness in the U.S. About 4 million people are afflicted with cataracts to some degree, and 40,000 people are blind as a result. Cataract surgery is the most frequent major surgery performed on Medicare patients.
signs and symptoms
signs and symptoms:
blurring of vision
gradual, painless loss of vision
glare
altered color perception
absent or abnormal red reflex with ophthalmoscopic exam: a cataract appears as a dark defect
lab findings:
not applicable
course and prognosis
The course is usually slow and progressive to total visual loss. Cataract retraction surgery can return vision to full with the aid of lens replacement or corrective spectacles or contact lenses. The prognosis is generally better for degenerative cataracts than developmental ones.
differential diagnosis
glaucoma: open angle
footnotes