Uveitis

What Is It?

Uveitis means inflammation of the part of the eye called the uvea. The uvea, also called the uveal tract, is a continuous layer of fibrous tissue that surrounds the eye. It is made up of three structures:

• The iris - The donut-shaped part that gives the eye its color

• The choroid - A membrane full of tiny blood vessels that lines the eye

• The ciliary body - A thick ring of tissue that helps control the shape of the lens, and is attached to the iris and to the front portion of the choroid

Various terms are used for the condition, depending on the part of the uvea affected. They include:

• Anterior uveitis (iritis) - Affects the front portion of the uvea, the iris

• Iridocyclitis - Affects the iris and the ciliary body

• Intermediate uveitis (also called pars planitis) - Affects the middle portion of the uvea, between the retina and the ciliary body

• Posterior uveitis (choroiditis) - Affects the back part of the uvea, the choroid

Diffuse uveitis - Inflammation of all portions of the uveaThe most common types of uveitis are anterior uveitis and iridocyclitis. Posterior uveitis is rare. Many cases of uveitis are related to an autoimmune disorder (such as ankylosing spondylitis, lupus, juvenile rheumatoid arthritis, multiple sclerosis or sarcoidosis ) or an infection, such as toxoplasmosis, herpes, syphilis or cytomegalovirus (especially in patients with AIDS). In up to half of cases, the cause is not known, but recent research has linked certain genes to the development of the disease. One possibility is that some people are prone to uveitis because they have genes that program the immune system to attack the uvea, a process that may be triggered by an infection.

Symptoms

Symptoms of uveitis can vary depending on the location of the inflammation. Severe symptoms generally are associated with anterior uveitis, and can include:

• Eye pain

• Eye redness

• Sensitivity to light

• Blurred or decreased vision

Intermediate and posterior uveitis can have more subtle symptoms, including small specks or clouds that move in your field of vision, called floaters, and decreased vision.