An eye
problem may be the first manifestation of an underlying
systemic disease. Since the eye is derived from the same embryonic
tissues as the other organs of the body, many systemic disease are
associated with ocular signs and symptoms. Young students study
circulation by using a light microscope to observe blood moving in
the tail of a fish. Ophthalmologists use an ophthalmoscope to see
the circulation of the eye. The retina is actually part of the
central nervous system and connected to the brain by the optic
nerve. The ophthalmologist is able to visualize a component of the
central nervous system without a MRI or CT scan. The cornea, human
lens, retina, and optic nerve can be affected by medications that
are ingested or injected. Periodic eye examinations can help
prevent cataracts and glaucoma, and loss of sight from optic nerve
or retina damage from these medications.
An eye
examination may be the first sign of a disease affecting the
rest of the body. An eye examination by Dr. Eldridge led to
the diagnosis of the following systemic
diseases: