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Cataract

Cataract

Opaque pupil
This is caused here by a "cataract." A cataract causes blurred vision by disturbing the coherence of light rays as they pass through the eye, so that there is no clear focus on the retina.

Opacification can begin anywhere in the lens, and may be quite minimal at first. One way to judge the density of a cataract is by how much it interferes with your view of the retina through the ophthalmoscope!

Cataract
Cataract is another word for lens opacity (the Greeks thought the whiteness looked like a waterfall). It is the most common cause of blindness in the developing world, where people do not have access to an ophthalmic surgeon.

The most common cause of cataract is simply the aging process. (But not all elderly people get them!) Senescence causes the lens protein to degenerate and lose its transparency. Other causes are inflammation, trauma, metabolic, and hereditary disorders.

Cataracts are removed surgically, by making a small incision at the corneal edge, removing the anterior lens capsule, and ultrasonically fragmenting the lens with a probe. The posterior lens capsule is left behind.

A plastic lens implant, whose refractive power mimics that of the extracted lens, is placed into the capsular bag.

Modern cataract surgery is successful in restoring normal vision in about 99% of eyes, provided there is no other reason for subnormal sight.

What to do?
Refer non-urgently to an ophthalmologist. Cataracts are removed when the patient and surgeon agree that the cataract is compromising vision enough to interfere with life's tasks and pleasures, and when the risks and benefits justify surgery. A plastic lens implant (intraocular lens) is placed into the space previously occupied by the natural (crystalline) lens.

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