Fuchs’ Corneal Dystrophy

 The human body 13 remarkable in its apparent foresight
in preparation for age and disease. In all parts of the
body, as children we are provided with many times the
necessary cells for maintenance of bodily activity. As an
example, we are provided with two lungs and two kidneys when
only one would suffice. Thus the fundamental concept of
redundancy, heard most often in relation to the space
program, is nature's way of providing continuous bodily
function as we age and suffer the many traumas of daily
living.
The cornea is no different in this respect. While the
cornea appears as a simple transparent surface, devoid of
activity, on closer examination it becomes one of the most
active and energy consuming organs of the body. In order to
appreciate the diseases which affect this organ we must
first consider how it functions. Our modern appreciation of
the processes inherent in the functioning of the cornea is
quite recent, dating from the mid 1950's in the work of Dr.
David Maurice of Stanford University. The story of his
discovery and the reasoning which led to it are one of the
great adventures of ophthalmology.
It has been known for several centuries that the cornea
represented one potential cause of blindness as people aged.
In past times diseases of the cornea were often confused
with cataracts or diseases of the lens, a structure which
lies behind the cornea. When corneal scars were obvious, the
treatment most often employed was cosmetic, as by Galen in
the early Roman period who tattooed pigment into the cornea
to hide its appearance. when clinical biomicroscopy—er~;+—~~m~~H
examination of the eye under magnification with a slit beam
was introduced, it became possible to differentiate corneal
disease from diseases of the lens. Thus a disease related
to aging was described in the advanced stages by Dr. Fuchs
in 1910 which developed in the following manner. As one
examined older patients, one might begin to appreciate very
small lumps or "guttata" on the back surface of the cornea
associated with a "beaten metal" appearance when the cornea
was examined with a rear illumination reflected off the
iris, so called retro-illumination. That is the cornea
appeared as a piece of copper night look after it had been
worked with a ball-peen hammer. As these patients aged,
they gradually began to lose vision and the corneas assued
a very hazy appearance. By directing a slit of light across
the cornea, Dr. Fuchs could estimate the thickness of the
cornea and thus noted thickening of the cornea particularly
in the center. In addition in advanced cases, the surface
of the cornea became quite cystic with so called "bu1lae'
appearing in advanced stages. These patients noted