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choroid

(KOR-oyd)
A thin layer of tissue that is part of the middle layer of the wall of the eye, between the sclera (white outer layer of the eye) and the retina (the inner layer of nerve tissue at the back of the eye). The choriod is filled with blood vessels that bring oxygen and nutrients to the eye.
Eye anatomy; two-panel drawing showing the outside and inside of the eye. The top panel shows the outside of the eye, including the eyelid, pupil, sclera, and iris. The bottom panel shows the inside of the eye, including the cornea, lens, ciliary body, retina, choroid, optic nerve, and vitreous humor.Enlarge this image in new window
Anatomy of the eye showing the outside and inside of the eye, including the eyelid, pupil, sclera, iris, cornea, lens, ciliary body, retina, choroid, optic nerve, and vitreous humor.
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