glossary

The ?front window? of the eye. Transparent front part of the globe shaped like a slightly domed cap. It is the primary focusing structure with the lens. Transparent membrane in the front of the eye that covers the iris, pupil, and anterior chamber and provides most of an eye’s optical power.

Sightless area within the visual field of a normal eye, where the optic disc attaches the optic nerve to the eye. Caused by absence of light sensitive photoreceptors where the optic nerve enters the eye.

Opacification of the crystalline lens. An extraction of the lens is usually replaced by an intra-ocular lens (implant). Clouding of the crystalline lens, which may prevent a clear image from forming on the retina. If visual loss becomes significant, surgical removal is required. Types of cataracts include traumatic, congenital and age-related. .