Scintillation imaging has been used as an aid in detecting and documenting patterns of abnormality for many organ systems of the body. The synovial membrane of the joints of the extremities may be studied by means of tracers of 131I- or 99mTc-tagged albumin (1, 2). The use of 99mTc pertechnetate provides a similar localization in the synovial membrane in cases of active synovitis without administering exogenous protein. When employed with a stationary imaging device such as an Anger camera, images of all the joints of the extremities may be obtained within a period of thirty minutes to one hour. The synovial membrane image has been useful for the early detection of synovitis and for the documentation of the pattern of synovitis at a specific time. It has also aided in determining if joint pain was due to active synovitis when laboratory studies, roentgenograms, and physical examination were equivocal (3). Method The thyroid gland is blocked with Lugol's solution or a potassium iodide with a dosage schedul...