Progressive
opacity of the normally clear crystalline lens can lead to formation of a
cataract(#22005).These
changes may involve both the nucleus and the cortex of the lens (#22006,
#22008).Nuclear changes are
characterized by progressive crosslinking and insolubilty of crystalline
proteins.This leads to a
progressive hardening of the nucleus and discoloration which is initially
yellow and can eventually become a dark brown or brunescent color(#22009,
#22262).Cortical changes may begin as small peripheral water clefts
with globular degenerative changes of the cortex.This may eventually coalesce into dense bands of opaque cortical
material.In addition, lens
epithelial cells may migrate posteriorly and form swollen bladder
cells(#22011, #22188).Also,
anterior lens epithelial cells may undergo a fibrous metaplasia leading to
a thick fibrous plaque between the anterior lens capsule and the anterior
epithelial cells (#22012).
