Functional reserves of the thyroid gland in thyrotoxicosis remission

: A test with intramuscular injection of 5 or 10 U of TTH was carried out in 47 patients suffering from diffuse toxic goiter, including 34 cases at the stage of thyrotoxicosis remission. Results of this test were evaluated by the changes of I131 absorption by the thyroid gland and of the blood protein-bound iodine level. The thyroid gland TTH sensitivity was found to be diminished in 16 patients with thyrotoxicosis remission. The reaction was absent most regularly in patients with ophthalmopathy. This denotes a latent form of thyroid insufficiency and suggest that the patients with the negative response to the exogenous TTH are in the "risk group" in respect to the development of manifest hypothyroidism.