Today I’d like to talk about cataracts. The term cataract refers to the clouding of the crystalline lens of the eye. The lenses in children are clear and flexible as we age the lens loses its flexibility and in most people becomes cloudy and yellowed. The decrease in flexibility continues up to about 55 or 56 and results in the inability to focus at near. Reading glasses and bifocal lenses help these patients with their near and intermediate vision. The yellowing and clouding of the lens are signs of a developing cataract. As the cataract matures or worsens, vision decreases, glare becomes more pronounced and perception of color can become distorted. Most cataracts are age related but they can also form from trauma to the eye, reaction to certain medications, and can also be caused by some diseases.
There are several different kinds of cataracts. They differ in how they affect the lens, their severity in vision loss and how fast they progress. The following is a list of the different types of age related cataracts listed in order of severity of vision loss.
Nuclear Sclerotic Cataracts
They are the most common cataract. They typically affect vision the least and are slow forming. They affect the center of the lens making it yellow and cloudy. Over time the lens yellowing can become almost brown and the patient can have problems with color perception. I had one patient tell me after cataract surgery he was surprised to find the green carpet he had bought was in fact blue. Another symptom patients will experience is increased glare as the clouding of the lens worsens. When the glare reaches a certain level cataract surgery is indicated.
These are cataracts that affect the peripheral parts of the lens. They form as white streaks or spokes at the edge of the lens and work inward toward the center. As they progress to the center they will cause more visual problems, primarily increased glare. At this point they are usually removed.
Posterior Subcapsular Cataracts
These are the fastest progressing and most visually debilitating cataract. They form on the back of the lens directly in line with the pupil. Because of their location they affect the light rays entering the eye the most. They cause problems with reading and near work, decreased vision in bright light and halos in dim illumination. Once they begin to form they can quickly cause severe visual loss.
Cataracts are easy to diagnose. Once found we need to monitor the patient form progression of the cataract and the visual problems they cause. Cataracts are annoying at best and visually debilitating at worst. The good thing about cataracts is that in most cases they are easily removed and once removed, good vision is completely restored. I’ve had many patients who are hesitant about having their cataracts removed but once they see how much better vision they have and how easy the procedure was, they can’t wait to have the fellow eye done.
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