Why are optometrists important?

The ophthalmoscope is an instrument used to examine the fundus, or eyeball interior, to determine visually the condition of the retina, optic disc, and internal blood vessels. Certain pathologic conditions such as Diabetes mellitus, arteriOSclerosis, and degenerative changes of the optic nerve and retina can be detected by such an examination.

-page 375 of Human Anatomy & Physiology Laboratory Manual, 10th Ed, Marieb & Mitchell