Optic
AtrophyIntroduction: When the optic nerve stops
working, it undergoes degeneration. Here is a cross section through the back of
the eye where the optic
nerve has atrophied. You can clearly see a dip where there should
be nerve tissue. This is due to the shriveling up of a bundle of nerve fibers
from the optic nerve. This eye would have been completely blind. Signs
and Symptoms:
Depending
on what the underlying pathological process is, the symptoms can be quite different.
For instance, in a multiple sclerosis patient it may take a number of months or
years before a complete optic atrophy develops. Long before the progressive optic
atrophy develops, there may have been double vision first because of weakness
in the eye muscle coordination. On the other end of the scale there might
be a sudden loss of vision because of a brain tumor that puts pressure from behind
the eye onto the optic nerve leading to a sudden reversible optic atrophy. If
the tumor is benign and can be neurosurgically removed, part or all of the vision
can be recovered provided the neurosurgeons is consulted in time. Diagnostic
Test: When the physician looks through the ophthalmoscope or examines
the eye with the help of the slit lamp, this picture
of the fundus with optic atrophy would be seen. This was found in
a patient who was blind on that eye from multiple sclerosis. Treatment: Unfortunately,
if optic atrophy has taken place and the nerve tissue is lost, nothing can be
done to help this patient. However, if in an acute optic atrophy case the eye
pressure is found to be too high (glaucoma), the eye pressure can be quickly lowered
and the patient may recover some or all of the vision. Similarly, as already pointed
out in the case where a benign tumor puts pressure from behind onto the eye, removal
of the tumor can often restore most, if not all of the vision.
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