Supervoltage orbital radiotherapy in 36 cases of Graves' disease

Thirty-six patients who had clinically progressive Graves' dysthyroid orbitopathy were treated with supervoltage orbital radiotherapy. Twenty-three of the patients had discontinued the use of orally administered prednisone after developing intolerable side effects. Medical contraindications prevented seven patients from receiving systemic corticosteroid treatment. Six additional patients declined to take prednisone and chose orbital radiotherapy as their primary treatment. All patients were treated with one radiotherapy protocol wherein a 6 MV linear accelerator delivered 2,000 cGy to the midplane of both orbits in ten fractions. None of the 36 patients was treated with corticosteroids during the orbital radiotherapy treatment interval. We encountered three patients who failed to respond to orbital radiotherapy and required supplemental immunosuppression to arrest progression of Graves' disease. The remaining 33 patients experienced stabilization or clinical improvement of their condition. None of the patients experienced complications from orbital irradiation. We believe supervoltage orbital radiotherapy is an effective means of treating Graves' dysthyroid orbitopathy.