The iris pigment epithelium (IPE) is a two-cell thick layer of cuboidal cells lying behind the iris. Both layers are jet black due to the numerous large melanosomes which pack the cytoplasm of each cell. Towards the central axis, the IPE terminates at the pupillary margin. Peripherally, the IPE is continuous with the ciliary epithelium, also double-layered but pigmented in only one layer. The ciliary epithelium is continuous in its turn with the multilayered retina, which has an outermost pigmented layer, the retinal pigment epithelium (RPE). Despite their very different functions and histological appearances, these regions have a common origin from the two layers of the embryological optic cup. The melanosomes of the IPE are distinctive, being larger, blacker and rounder than those in the ciliary epithelium or RPE.
Iris pigment epithelium is the scientific name for the color of an iris in the eye.
Read more about Iris Pigment Epithelium: Pathology
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“Light was a paste of pigment in our eyes.”
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