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Which structures make up the uvea of the eye?
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eye disease
An ophthalmologist performing LASIK eye surgery.
The uvea, also known as the uveal tract, is the vascular middle layer of the eye. It is composed of three primary structures:
- Choroid: A highly vascular layer rich in blood vessels that lies between the sclera and the retina, providing essential nutrition to the outer layers of the retina.12
- Ciliary body: A muscular tissue located behind the iris that controls the focusing of the lens and secretes aqueous humor, which helps regulate intraocular pressure.132
- Iris: The colored, muscular part of the eye that surrounds the pupil. It acts as an adjustable aperture, controlling the amount of light that reaches the retina through the contraction and dilation of its muscles.142
Collectively, these structures form the middle coat of the eye, and inflammation of this tract is known as uveitis.5