The
uvea is the vascular coat of the eye made up of the iris and ciliary body in the front part of the eye and the chproid which lines the back of the eye. It comprises a dense network of both large and small blood vessels (capillaries) supplied by larger vessels in the orbit. The uvea provides nutrition to, and removal of metabolic waste products from structures inside the eye. It has an important role in the immunological response of the eye to invading organisms (bacteria, fungi, parasites).
The most frequent diseases seen affecgting the uveal tract are inflammation (uveitis) and tumors (neoplasia) of the iris and ciliary body. Inflammation may arise from injuries to the eye, invasion by foreign organisms, or as part of chronic immune system activation in the eye - possibly initiated by infectious diseases (equine recurrent uveitis)