Cataract is a cloudiness of lens in the eye which leads to a decrease in vision and often develops slowly which can affect one or both eyes.
Geriatric dogs (usually beginning at 6 years of age) develop a hardening of the lens (Nuclear Sclerosis) that causes the lens to have a grayish appearance. The grayish-blue haze increases as the dog ages. Nuclear sclerosis is not a cataract, and does not usually interfere with vision.
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