Vascular Endothelial Growth Factor (VEGF) in Uveitis

This study will look for the presence in blood of a substance called vascular endothelial growth factor (VEGF) in patients with uveitis (eye inflammation). It will also look for this substance in eye fluid samples taken from patients with uveitis who are undergoing eye surgery. Some patients with uveitis experience some vision loss during an inflammatory attack because of swelling (edema) in a particular area of the retina called the macula, which is involved in visual acuity. It may be that VEGF is involved in the development of macular edema. Patients with uveitis who participate in this study will have about 10 cc (2 teaspoons) of blood drawn to be examined for VEGF. They will also undergo a procedure called fluorescein angiography to look at the blood vessels of the eye. A dye called sodium fluorescein is injected into the blood stream through a vein. After the dye reaches the blood vessels of the eye, photographs are taken of the retina. In addition, patients with uveitis who are undergoing eye surgery will have a tissue specimen (either aqueous fluid or vitreous gel) collected for examination for the presence of VEGF.