How Does an Age-Related Cataract Form?
There are several different causes of
cataracts. For each of these different
cataract causes, the reason the lens becomes cloudy will vary.
In the case of age-related cataracts (the most common cataract type), the cataracts form because of either protein clumpings or lens discoloration. Each of these will affect your vision differently.
Protein Clumpings
The lens consists mostly of water and protein. When the protein clumps up, it clouds the lens and reduces the light that reaches the retina. The clouding may become severe enough to cause blurred vision. Most age-related cataracts develop from protein clumpings.
When a cataract is small, the cloudiness affects only a small part of the lens. You may not notice any changes in your vision at first. Cataracts tend to develop slowly, so vision gets worse gradually. Over time, the cloudy area in the lens may get larger and the cataract may increase in size. Seeing may become more difficult, and your vision may get duller or blurrier.
Lens Discoloration
As the clear lens slowly colors with age, your vision gradually may acquire a brownish tint. At first, the amount of tinting may be small and may not cause a vision problem. Over time, increased tinting may make it more difficult to read and perform other routine activities. This gradual change in the amount of tinting does not affect the sharpness of the image transmitted to the retina.
If you have advanced lens discoloration, you may not be able to identify blues and purples. You may be wearing what you believe to be a pair of blue socks, only to find out from friends that you are wearing purple socks -- or even one purple and one blue sock.