Radioiodine Therapy for Hyperthyroidism Changing Pattern of Management over Three Decades at INMAS

Abstract

Iodine - 131 therapy is a relatively simple, effective and economical method of treating hyperthyroidism. Even fifty years after the introduction of radioactive iodine, there is no concensus on the approach for selection of the dose for treatment of hyperthyroidism. Since the last three decades, the approach for radioiodine therapy at this Institute has been to treat with low, fractionated doses to produce partial destruction of the thyroid gland leaving the patient sufficient functioning gland for normal hormone production. New in vitro diagnostic techniques including free T/sub 3/, T/sub 4/ and sensitive TSH assay have been introduced over the past decade for the diagnosis of hyperthyroidism. Changes in the thyroid radioactive iodine uptake in the population due to introduction of iodized salt, and the high incidence of persistent hyperthyroidism after low dose radioiodine therapy, have prompted to go for a proporptionate increase in the /sup 131/I original dose schedules based on goitre grades. This has led to nominal increase in the incidence of post therapy hypothyroidism. However, the basic principle of low, fractionated dose therapy is still being followed at this Institute, which appears suitable for our social and economic conditions