The eye is shaped much like a tennis ball, hollow inside with three different layers of tissue surrounding a central cavity. The outermost is the sclera (white coat of the eye) and the innermost is the retina (image-gathering tissue in the back of the eye much like the film in a camera).
The middle layer between the sclera and the retina is called the uvea, from the Greek word "uva" meaning grape. In the laboratory, it looks much like a "peeled grape." When the uvea becomes inflamed, the condition is called uveitis.
The uvea contains many of the blood vessels which nourish the eye. Inflammation of the uvea can affect the cornea, the retina, the sclera, and other vital parts of the eye.
Since the uvea borders many important parts of the eye, inflammation of this layer may threaten sight more seriously than the more common inflammation of the outside layers of the eye.
When the uvea is inflamed near the front of the eye in the iris, it is called iritis. If the uvea is inflamed in the middle of the eye involving the ciliary body, it is called cyclitis. If the inflammation is in the back of the eye affecting the choroid, it is called choroiditis.Causes
Uveitis has many different causes. It may result from a virus (such as shingles, mumps or herpes), a fungus (such as histoplasmosis), or a parasite (such as toxoplasmosis). In most cases, the cause remains unknown.
Uveitis can also be related to disease in other parts of the body, such as arthritis, or come as a consequence of injury to the eye.Symptoms
Symptoms include light sensitivity, blurring of vision, pain, and redness of the eye. Uveitis may come on suddenly with redness and pain, or it may be slow in onset with little pain or redness, but gradual blurring of vision.Diagnosis
Your physician will take a medical history and perform a physical examination including an eye exam.Treatment
Prompt treatment is necessary to minimize any loss of vision. Eye drops, especially steroids and pupil dilators, are medications used to reduce inflammation and pain.
For deeper inflammation, oral medication or injections may be necessary. Complications such as glaucoma (high pressure in the eye), cataracts (clouding of the lens of the eye), or new blood vessel formation (neovascularization), also may need treatment in the course of the disease. If complications are advanced, conventional or laser surgery may be necessary.
Uveitis in the front and middle part of the eye (iritis or cyclitis) is commonly more sudden in onset, generally lasting six to eight weeks, and in the early stages can usually be controlled by the frequent use of drops. Often, this type of uveitis cannot be given a specific cause.
Uveitis in the back part of the eye (choroiditis) is commonly slower in onset and may last longer, and is often more difficult to treat.Questions
What parts of the eye are inflamed?
What is the cause of the inflammation?
What are treatment options?
Would eye drops help?
Under what circumstances would surgery be recommended?