| Normal Vision |
A cataract is a clouding of the lens of the eye and light that passes through the lens to the retina is scattered. The scattered light causes images to be blurred and visual acuity is reduced. |
As we age, the lens of the eye yellows and becomes fixed and unable to focus, the pupil does not dilate very well to changes in illumination, and the retina and cortex become less able to process visual information. Contrast sensitivity decreases, visual acuity drops somewhat, and vision in low light levels suffers. |
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