Radioiodine treatment of solitary functioning thyroid nodules

Forty-eight patients with hyperthyroidism due to a single toxic nodule have been treated with radioiodine (131I). The mean follow-up period is 37 months. All patients were rendered euthyroid and no cases of hyperthyroidism have been observed. Forty patients required only one dose of 131I to render them euthyroid, six patients required more than one dose and two patients initially rendered euthyroid relapsed during follow-up and required further 131I treatment. It is concluded that a single fixed dose of 131I is a simple, effective treatment for a solitary toxic thyroid nodule and does not cause hypothyroidism.