Radioiodine treatment, ablation, and ophthalmopathy: a balanced perspective

In some patients with Graves' disease, ophthalmopathy develops or deteriorates after initiation of therapy for hyperthyroidism. The possible relationship between the management of hyperthyroidism and the course of ophthalmopathy has been addressed in several studies but with conflicting results. The overall impression, when comparing these studies, is that there is no definite difference between the three forms of therapy for hyperthyroidism with regard to the course of ophthalmopathy, although there are more studies suggesting that 131I carries a higher risk for aggravating the eye disease. However, many of these studies are retrospective, contain few patients, have a short follow-up time, and include patients who have received more than one type of treatment. We performed a prospective study in which patients were randomized to either antithyroid drugs, subtotal thyroidectomy, or 131I. We found that 33% of the patients treated with 131i deteriorated compared with 10% and 16% of patients treated with antithyroid drugs and surgery, respectively (p = 0.02). The risk was greater when patients had very high pretreatment thyroid hormone levels. On the other hand, patients treated with 131I were given thyroxine later than the other patients, although this fact did not appear to be of importance for the results. In another retrospective study, we showed that early administration with thyroxine can reduce the risk for ophthalmopathy, and we now are undertaking a prospective study in which treatment with antithyroid drugs is compared with 131I treatment and early thyroxine. Our guidelines for ablative therapy in patients with progressive ophthalmopathy are presented.