Effects of radioiodine therapy in hyperthyroidism (thyroid function, thyroid volume, Graves' ophtalmopathy, thyrotoxic heart disease).

The study group consisted of 135 hyperthyroid patients--128 with Graves' disease and 7 with toxic multinodular goiter. A single dose of radioiodine was given in 110 cases (81.48%), two doses in 22 patients (16.3%) and three doses in 3 patients (2.22%); mean total dose was 6.8 mCi (range = 3-24 mCi). The main goal of radio iodine therapy is to achieve euthyroidism; after radioiodine treatment, 61 patients (45.2%) were euthyroid, 60 patients (44.4%) with permanent hypothyroidism and 14 (10.36%) with PERSISTING HYPERTHYROIDISM--the mean duration of follow-up being 4.2 years. After radioiodine therapy, goiter became absent in 30 patients (28%); in those patients, goiter was moderately enlarged or large before therapy. Around 63% (12 cases) of the patients with thyrotoxic atrial fibrillation reverted to sinus rhythm. During the last four years (1990-1994) the patients with Graves' ophthalmopathy from the study group were treated with Prednisone after radioiodine therapy; this corticotherapy contributes to the lower percentage (1.5%) of worsening Graves' ophthalmopathy after radioiodine therapy.