Human eye layer, known as the fibrous tunic, is composed of the cornea and sclera. The middle layer, known as the vascular tunic or uvea, consists of the choroid, ciliary body, pigmented epithelium and iris. The innermost is the retina, which gets its oxygenation from the blood vessels of the choroid (posteriorly) as well as the retinal vessels (anteriorly). The spaces of the eye are filled with the aqueous humour anteriorly, between the cornea and lens, and the vitreous body, a jelly-like substance, behind the lens, filling the entire posterior cavity. The aqueous humour is a clear watery fluid that is contained
Retinal pigment epithelium The RPE is composed of a single layer of hexagonal cells that are densely packed with pigment granules. At the ora serrata, the RPE continues as a membrane passing over the ciliary body and continuing as the back surface of the iris. This generates the fibers of the dilator. Directly beneath this epithelium is the neuroepithelium (i.e., rods and cones) passes jointly with the RPE. Both, combined, are understood to be the ciliary epithelium of the embryo. The front end continuation of the retina is the posterior iris epithelium, which takes on pigment when it enters the iris. When viewed