A. Uveitis is inflammation of one or more of the parts of the uvea, the layer of tissue that lies between the retina and the white of the eye (the sclera). These three layers -- the retina, uvea, and sclera -- surround the cavity of the eyeball, which contains the gel-like vitreous humor.
Uveitis may develop suddenly, and one or both eyes may be affected. It can cause painful reddening of the eyeball, blurred vision, light sensitivity, and floaters or other debris in the field of vision. You may have all or none of these symptoms, depending upon the part of the uvea that's affected. It's a serious condition that can result in scarring and even blindness if left untreated.
Uveitis has many different causes, including infections, autoimmune conditions, or injury to the eye (including eye surgery). Rarely, medications may cause uveitis, including bisphosphonates (especially when given intravenously), the antibiotics rifabutin (Mycobutin) and moxifloxacin (Avelox), and the antiviral drug cidofovir (Vistide). In about 30 percent of cases, the cause is unknown. Some patients develop "masquerade syndromes," which resemble uveitis but have other causes, such as a tear in the retina or a type of lymphoma.
The uvea has three parts: the iris (the colored part of the eye); the ciliary body (the structure near the iris that makes fluid within the eye); and the choroid (a layer of blood vessels that nourish important parts of the eye, including the retina). Anterior uveitis, the most common form, affects the front part of the eye (the iris and ciliary body). In intermediate uveitis, the inflammation affects mostly the vitreous humor. And in posterior uveitis, the retina or choroid at the back of the eye is affected. Sometimes the whole eye is affected.
To diagnose uveitis, an ophthalmologist will examine the eye with a slit lamp, a magnifying instrument that permits a detailed view of the eye structures. Treatment is based on the cause.
Infectious uveitis is treated with an antibiotic, antifungal, antiviral, or other medication. (Topical steroid eyedrops are often added to minimize the inflammation while the medication is working.) Noninfectious uveitis is usually treated with steroids applied topically in the form of eyedrops, injected into the eye, or taken by mouth.
A surgical implant that slowly releases steroids within the eye has been approved for severe uveitis. All forms of steroid therapy may cause glaucoma or cataracts. Uveitis can also cause cataracts and glaucoma, but it must be treated to preserve vision. If cataracts or glaucoma develop during treatment, your ophthalmologist will recommend appropriate additional therapy.
Treating uveitis may require both an ophthalmologist and an internist. Once your ophthalmologist has confirmed the diagnosis, it's a good idea to tell your internist or primary care provider. She or he may want to take a detailed history, perform a physical exam, and order laboratory tests to determine whether your uveitis is related to a treatable underlying condition. It's also important to follow up with your ophthalmologist to make sure the treatment is working and to check for complications. -- Celeste Robb-Nicholson, M.D., Editor in Chief, Harvard Women's Health Watch