Radiotherapy for Graves' orbitopathy: randomised placebo-controlled study

Background The best treatment (steroids, irradiation, or both) for moderate ly severe Graves' orbitopathy, a self-limiting disease is not known. We tes ted the efficacy of external beam irradiation compared with sham-irradiatio n. Methods In a double-blind randomised clinical trial, 30 patients with moder ately severe Graves' orbitopathy had radiotherapy (20 Gy in ten fractions), and 30 were assigned sham-irradiation (ten fractions of 0 Gy). Treatment o utcome was measured qualitatively by changes in major and minor criteria an d quantitatively in several ophthalmic and other variables, such as eyelid aperture, proptosis, eye movements, subjective eye score, and clinical-acti vity score at 24 weeks. Findings The qualitative treatment outcome was successful in 18 of 30 (60%) irradiated patients versus nine of 29 (31%) sham-irradiated patients at we ek 24 (relative risk [RR]=1.9 [95% CI 1.0-3.6], p=0.04). This difference wa s caused by improvements in diplopia grade, but not by reduction of proptos is, nor of eyelid swelling. Quantitatively, elevation improved significantl y in the radiotherapy group, whereas all other variables remained unchanged . The field of binocular single vision was enlarged in 11 of 17 patients af ter irradiation compared with two of 15 after sham-irradiation. Nevertheles s, only 25% of the irradiated patients were spared from additional strabism us surgery. Interpretation In these patients with moderately severe Graves' orbitopathy , radiotherapy should be used only to treat motility impairment.