Uveitis is the medical term used to describe inflammation of the uvea. The uvea is the middle layer of the eye that supplies blood to the retina. The uvea is made up of the following three parts:
- The iris -- the colored part of the eye.
- The ciliary body -- the part of the eye that releases aqueous humor. It also contains the ciliary muscles, which change the shape of the lens to help the eye focus.
- The choroid -- a layer of blood vessels and connective tissue that supplies nutrients to the inner part of the eye.
Anterior uveitis occurs when just the front part of the uvea is inflamed. This type of uveitis is sometimes called iritis because usually just the iris is affected. Symptoms of anterior uveitis may include eye pain, redness, light sensitivity, and blurred vision.
Posterior segment uveitis affects the ciliary body or choroid. The retina and its blood vessels may also be inflamed. People usually do not experience pain with posterior segment uveitis. Symptoms may include decreased vision and floating spots across the field of vision ("floaters").
If not treated properly, uveitis can cause complications that damage the eye and affect vision. Complications of untreated uveitis may include:
- High pressure inside the eye
- Damage to the optic nerve
- Loss of vision.
Uveitis may be caused by a variety of things, including infections or autoimmune diseases. Oftentimes, however, the exact cause of uveitis is unknown. Ozurdex is only approved to treat noninfective uveitis (not caused by an infection) affecting the posterior segment of the uvea.