Radiotherapy for the treatment of thyroid eye disease—a prospective comparison: Is orbital radiotherapy a suitable alternative to steroids?

Background and aims: To evaluate the efficacy of orbital radiotherapy (OR) for the treatment of thyroid eye disease (TED). Methods: Thirty-five consecutive patients with active TED with contraindications to steroid therapy received a course of OR. Bilateral retrobulbar irradiation was performed with a total dose of 20 Gy. 7-points clinical activity score (7-CAS), ocular motility, visual acuity (VA), exophthalmos and eyelid retraction were prospectively evaluated at 3, 6 and 12 months and compared with baseline data. Results: There was a statistically significant improvement in 7-CAS at 3, 6 and 12 months post-treatment (p < 0.05). Ocular motility disturbances improved at 6 and 12 months (p < 0.05). Visual acuity remained stable; there was no significant change in exophthalmos (mean 24 mm, SD 3 mm) or eyelid retraction (marginal reflex distance mean 6 mm, SD 1.5 mm) during the follow-up period. No side effects were registered. Conclusions: This study suggests that OR might be effective in reducing 7-CAS and ocular motility disturbances. No significant improvement in proptosis or eyelid retraction should be expected from this treatment. OR might be considered a suitable alternative treatment in TED for patients who cannot tolerate steroids.