WHAT IS CATARACT BLINDNESS?

There are an estimated 45 million blind adults in the world and this is likely to increase to more than 75 million by the year 2020. In most countries of Asia and Africa, cataract accounts for approximately half of all blindness. Over 80% of the blind live in developing countries with India accounting for the most cases world-wide (23.5% of all cases). While blindness is mainly a problem of developing countries, it is a problem which can be avoided in up to 90% of the cases.

A cataract is a clouding of the eye's lens that can cause vision problems. The most common type of cataract is related to aging. In its early stages, a cataract may not cause a problem. The cloudiness may affect only a small part of the lens. However, over time, the cataract may grow larger and cloud more of the lens, making it harder to see. Because less light reaches the retina, vision may become dull and blurry.

For an early cataract, vision may improve by using different eye glasses, magnifying lenses, or stronger lighting. If these measures don't help, surgery is the only effective treatment. This treatment involves removing the cloudy lens and replacing it with a substitute lens. In most cataract surgery, the removed lens is replaced by an intraocular lens (IOL). An IOL is a clear, artificial lens that requires no care and becomes a permanent part of your eye. With an IOL, the patient has improved vision because light is able to pass through and focus on the retina. Patients do not feel or see the new lens.

Sometimes, a cataract should be removed even if it doesn't cause problems with your vision. For example, a cataract should be removed if it prevents examination or treatment of another eye problem, such as age-related macular degeneration or diabetic retinopathy.

There are two primary ways to remove a cataract:

Phacoemulsification

This surgery involves making a small incision on the side of the cornea, the clear, dome-shaped surface that covers the front of the eye. The doctor then inserts a tiny probe into the eye. This device emits ultrasound waves that soften and break up the cloudy center of the lens so that it can be removed by suction. Most cataract surgery done today uses the phacoemulsification technique.

Extracapsular Surgery

This surgery involves making a slightly longer incision on the side of the cornea and removal of the hard center of the lens. The remainder of the lens is then removed by suction.