Retinitis pigmentosa is a group of related eye disorders caused by variations in 60 genes that affect the retina (terms highlighted in teal are labeled on the diagram of the

Retinopathy of prematurity (ROP) is an eye disease that affects premature or underweight babies (babies who weigh less than 3 pounds at birth). Abnormal blood vessels grow in the retina,

Light-sensitive cells in the retina that work best in darkness or dim illuminations.

Innermost layer of the eye containing light sensitive nerve cells and fibers connecting with the brain through the optic nerve and nourished by a network of blood vessels; receives image

Measurement of the focusing characteristics of the eye to determine refractive error and the need for prescription glasses.