Contemporary methods of radionuclide diagnosis and radioiodine therapy of the toxic goiter

A multidisciplinary radionuclide program has been worked out for optimization of radionuclide diagnosis and radioiodine therapy of the toxic goiter. It comprises in vivo and in vitro methods of investigation. The program consists of selected studies, dosimetric planning of treatment and a study of thyroid function after therapy. The in vivo technique was employed to study sup(99m)Tc early uptake (on the 20th minute) and 131I uptake after 24, 48 and 72 h. Scintigraphy of the thyroid gland was perfomed. The in vitro technique was used to define the following induces: the blood serum thyroxinbinding ability, the index of free thyroxin, an effective thyroxin coefficient, the content of total thyroxin, triiodothyronine and the thyreotropic hormone (TTH). The modified Levinger formula was used to define an absorbed dose. The most effective radiotherapy was achieved at a dose of 70-80 Gy for the diffuse toxic goiter and 100 Gy for the nodular and mixed type. A total of 577 patients with varying forms of the toxic goiter were examined and underwent radioiodine therapy according to the above program. Cure and prolonged remission were noted in 91.3% of the patients. The aggravation of thyreotoxicosis was noted in 15% of the patients on the firts days after 131I uptake. Hypothyreosis was noted in 2%