Cataracts

The incidence of cataracts increases steadily after 50 years of age, and is nearly 50% among people 75 years of age.

Maryann Hopkins, Pharmacist, Grace Hospital, Ottawa

Seeing is one of our most useful ways of learning about the world around us. When we have clear vision, our eyes can sense millions of different aspects of light and colour. They collect millions of pieces of information and send them to the brain.

The various parts of our eyes contribute to how we see. The lens, located behind the pupil, focuses light that passes through the pupil on to the back of they eye (retina) and protects the retina from harmful ultraviolet light. It works very much like a camera lens. Normally, the lens consists of a clear gel held in pouch or capsule. It is flexible and can vary in thickness. Because of this, it can focus light from objects, whether they are near or far, to one point on the retina. the retina collects the information and sends it to the brain to complete the process of “seeing”.

As a lens ages, it becomes less flexible. the lens may also become cloudy and gradually take on a yellowish-brown colour. This cloudy, defective lens is called a cataract. With cataracts, vision becomes distorted. Blindness can eventually develop.

there are several causes of cataracts, including injury, chemicals, radiation, some eye conditions, diabetes, and the effects of some drugs, but the most common cause is aging. Age-related cataracts often result from a lifetime of exposure to sunlight. The incidence of cataracts increases steadily after 50 years of age, and is nearly 50% among people 75 years of age. Protective eyewear is recommended to decrease exposure to solar radiation, especially when participating in outdoor activities in bright sunlight.

Nothing can clear a cataract once it has developed. However, modern micro-surgery allows doctors to remove the cataract and dramatically improve vision. In the past, it was fairly common to remove the lens and use thick glasses to correct vision. Now, the foggy lens can be removed and a clear artificial one (intraocular lens) implanted exactly where the old one used to be or at the front in the anterior chamber of the eye. This type of surgery is almost always successful (up to 99% of the cases) in greatly improving vision. This is one of the most common and successful types of eye surgery. It is usually done as a short-stay procedure (home from hospital or clinic within a few hours of being admitted). The individual will have to use eye drops at home for a few weeks and take precautions not to damage the newly operated eye, a small price to pay for improved sight!