Active retrobulbar inflammation in Graves' ophthalmopathy visualized by Tc-99m DTPA SPECT

An orbital inflammatory process is present in patients with Graves' ophthalmopathy (GO). With this condition, it is important to separate patients with an active orbital autoimmune process from patients with inactive GO, because immunosuppressive treatment is useless in the latter group. The authors report a case of active GO and elevated Tc-99m DTPA accumulation in the retrobulbar space, indicating active retrobulbar inflammation. The authors present coregistered magnetic resonance slices at the same transaxial orbital level and SPECT images obtained using the somatostatin analog Tc-99m depreotide, plus comparable images of a patient with inactive GO.