Improvement of radioiodine therapy of benign thyroid disorders: comparison of results from 1972-1978 and 1979-1983

Several improvements of radioiodine therapy of benign thyroid disorders have been introduced in 1979: 1. Exact determination of thyroid/goiter volumes by using ultrasonography in 2 projections. 2. Better determination of the radioiodine kinetics in the pretherapeutic state by more frequent measurements during 5 days (hyperthyroidism) or delayed measurements up to 14 days (nontoxic goiter). 3. Whole-body-measurements of patient's therapeutic activity with and without shielded thyroid gland to determine the percentage of extrathyroidal activity. 4. Introduction of a dose of 400 Gy (40000 rd) instead of 300 Gy for the elimination of autonomous adenoma. 5. If the desired dose would not be reached (less than 80% in case of differences between diagnostic and therapeutic kinetics) the patient got a second activity compensating this lack. Comparisons regarding the percentages of primarily successful tharapies, numbers of necessary repeated tharapies, other necessary requirements (thyrostatic medication), resulting cases of hypothyroidism, differences between antibody-positive and -negative cases of hyperthyroidism were performed each in the phase before and after installation of described improvements. Results are satisfying. The necessity of additional measurements and how to simplify the procedure will be discussed. (Author)