1The Third Department of Internal Medicine, Showa University School of Medicine, 2Department of Surgery, Showa University School of Medicine, 3Ito Hospital
Graves' disease, Hemodynamics, Superior thyroid artery, Duplex scan
The blood flow of common carotid and superior thyroid artery was measured using Duplex scanning system in 16 normal volunteers and 54 hyperthyroid and 44 euthyroid patients with Graves' disease. This instrument which is equipped with 10 MHz B mode and 4.5 MHz pulse Doppler is able to measure blood flow in those arteries non-invasively and quantitatively. In patients with Graves' disease, the diameter, time average velocity, peak velocity and flow on both arteries were significantly higher than those in normal volunteers. After treatment all parameters of carotid artery, except for diameter, were significantly lower, while the peak velocity of superior thyroid artery was only significantly lower than those of hyperthyroid patients. Furthermore all parameters of superior thyroid artery were significantly correlated with the size of thyroid and its peak velocity was significantly correlated with serum free thyroxine or free triiodothyronine levels. But there was no correlation between all parameters of superior thyroid artery and thyroid 123I uptake value or TSH recepter antibody activity. From these data, it was suggested that blood flow of common carotid artery was influenced upon thyroid function, while on superior thyroid artery it was influenced upon not only thyroid function but also the size of thyroid in patients with Graves' disease.