The Retinal Pigment Epithelium (RPE): The retinal pigment epithelium is the pigmented cell layer just outside the neurosensory retina. It serves as a source of nutrients for retinal visual cells. This retinal layer is firmly attached to the underlying choroid and overlying retinal visual cells.
When viewed from the outer surface, these cells appear smooth and hexagonal in shape.u00a0
The Retinal pigment epithelium forms the outer portion of the blood-retinal barrier.