[Methodological and clinical aspects of radionuclide diagnosis of thyroid diseases]

A multimodality radionuclide study including thyroscintigraphy, thyroprofilography, radioimmunoassay to determine the levels of thyroid hormones and TSH in the blood serum, and a new method of radionuclide thyrochronoscopy, was conducted in 32 patients with diffuse and nodular enlargement of the thyroid and in 5 patients of the control group. Thyrochronoscopic results were used to determine the percentage of absorption of 99mTc-pertechnate by the thyroid on the 20th minute, exponential index of absorption and clearance index. Their values turned out elevated in the patients with hyperthyroidism and suspicion for hyperthyroidism. Three degrees of marked compensatory capabilities of the thyroid tissue were singled out in the patients with the euthyroid status. The study showed the diagnostic value of thyrochronoscopic findings in examining thyroid function. In this view the use of cross-sectional scanning proved to be less informative. Not in all the patients did the levels of thyroid hormones and TSH correlate with thyrochronoscopic findings because they make it possible to reveal the disturbance of the compensatory capabilities of the thyroid before the development of hormonal changes. The use of radionuclide thyrochronoscopy enhances the diagnostic efficacy of a comprehensive study of the thyroid.