Choroid

A sheet of blood vessels behind the retina that brings oxygen and nutrients and removes waste. In wet AMD, blood vessels from the choroid grow into the retina, leak and cause damage.

The choroid is the layer of cells that sits just below the retinal pigment [j1] epithelial (RPE) cells. The choroid is rich in blood vessels, and is a major supplier of oxygen and nutrients to the RPE and photoreceptor cells. It also takes away the waste from these cells. The retinal degenerative disease, choroideremia, involves the complete atrophy/death of the choroid and retina.

[j1]In some cases, you've used pigmented and in others pigment, since I thought it was used more often without the "ed" I deleted it.