uvea

anatomy

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July 14, 2026

Quick Summary

The uvea is the pigmented, vascular middle layer of the eye, composed of the choroid, ciliary body, and iris. It is rich in blood vessels that supply nutrients to the retina.1234

The choroid is the posterior part of the uvea, providing blood supply to the outer retinal layers. The ciliary body, located behind the iris, contains muscles that adjust the lens for focusing and produces aqueous humor, which nourishes the cornea and lens. The iris, the colored part of the eye, is an adjustable aperture that controls the amount of light entering the pupil. Pigment in the iris determines eye color. Inflammation of the iris is known as iritis or anterior uveitis.2345

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uveitis
uvea (or uveal tract), the middle layer of tissue surrounding the eye that consists of the iris, ciliary body, and choroid. Uveitis can affect people at any age, but onset usually occurs in the third and fourth decades of life.
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uvea (or uveal tract), the middle layer of tissue surrounding the eye that consists of the iris, ciliary body, and choroid. Uveitis can affect people at any age, but onset usually occurs in the third and fourth decades of life.
Read More

human eye
The uvea
The middle coat of the eye is called the uvea (from the Latin for “grape”) because the eye looks like a reddish-blue grape when the outer coat has been dissected away. The posterior part of the uvea, the choroid, is essentially a layer of…
Read More
The middle coat of the eye is called the uvea (from the Latin for “grape”) because the eye looks like a reddish-blue grape when the outer coat has been dissected away. The posterior part of the uvea, the choroid, is essentially a layer of…
Read More