<qa>  What is the primary ocular disease?Retinal vasculitis is a major component of ocular inflammation that plays a critical role in retinal tissue damage and subsequent vision loss. Retinal vasculitis can occur as a primary ocular disease or secondarily, as a component of a systemic vascular disease. Unfortunately, little is known about primary retinal vasculitis. The initiating event in retinal vasculitis is most likely multifactorial. Nevertheless, the underlying pathologic mechanisms driving this process may be common. We hypothesize that there are biological markers of retinal vasculitis, such as, cytokines, chemokines, adhesion molecules, T-cell surface markers and autoantibodies which can be useful in determining disease progression, understanding mechanisms of pathogenesis, identifying therapeutic strategies and monitoring treatments. The purpose or objective of this study is to investigate selected biological markers to collect clinical and biologic information to better understand the natural history of conditions indicative of primary retinal vasculitis. 