A cataract is a cloudy area in the lens of the eye that blocks the
normal passage of light through the eye.
Cataracts that begin in the centre of the lens
(nuclear cataracts) are the most common cause of worsening nearsightedness in
adults. These cataracts are more common than the kind that begin to develop in
the outer part of the lens.
Nearsightedness associated with cataracts in the
centre of the lens is often classified with the
pseudomyopias, but it is actually a permanent change
in the way light focuses in the eye. Cataract surgery corrects the myopia as
well as the cataract.
The presence of
pathological myopia may affect how cataracts are
diagnosed and treated. It may be harder to tell whether nearsightedness is
getting worse because of the cataracts or because of the progression of
pathological myopia. People with pathological myopia who have cataract surgery
are at higher risk for
retinal detachment.
See a picture of an
eye with
cataracts
.