Thyroid Accumulation of 99Mtc-Dtpa in Graves Disease

99m Tc-DTPA dynamic renal scintigraphy for evaluating glomerular filtration rate was performed in a 29-year-old woman with hyperuricemia and Graves disease. Subsequently, 99m Tc-DTPA orbital scintigraphy was conducted to determine the activity of Graves ophthalmopathy. Thyroid accumulation of 99m Tc-DTPA was incidentally identified. This should be cautiously distinguished from 99m Tc-pertechnetate uptake, considering that the salivary glands, oral cavity, and stomach were not visualized. Our case demonstrates that augmentation of blood supply, enhancement of capillary permeability, and accumulation of inflammatory exudate may be involved in the pathological process of Graves disease.