The purpose of this study is to develop a relatively simple, accurate method of diagnosing sarcoidosis. Sarcoidosis is a disease in which granulomas (nodules of inflamed tissue) develop in various organs, such as the lungs, liver, skin and eyes. Disease symptoms vary depending on the tissues involved. Many patients develop uveitis (eye inflammation). Tissue biopsy-often a costly and difficult invasive procedure-is currently the only definitive diagnostic test for sarcoidosis. Other tests, such as blood and urine tests, do not provide definitive results.