ICD-11

This is a closed sac, having a distinct membrane and division compared to the nearby tissue. This diagnosis is of the thin, circular structure in the eye, responsible for controlling the diameter and size of the pupil and thus the amount of light reaching the retina. The color of the iris is often referred to as "eye color." It is also of the circumferential tissue inside the eye composed of the ciliary muscle and ciliary processes. It is triangular in horizontal section and is coated by a double layer, the ciliary epithelium.