Echographic findings and histological feature of the thyroid: a reverse relationship between the level of echo-amplitude and lymphocytic infiltration.

In 43 patients with Graves' disease, 5 patients with painless thyroiditis and 30 patients with Hashimoto-thyroiditis ultrasonographical observations and histological examinations by needle biopsy of the thyroid were carried out simultaneously. In all cases the level of echo-amplitude was well correlated with the rate of lymphocytic infiltrations and fibrosis. In cases which exhibited marked lymphocytic infiltrations in the thyroidal biopsy specimen, no apparent echoes or very low amplitude echoes were observed in the whole thyroid and in cases in which replacement with lymphocytic infiltration was observed in almost a half part of the thyroid, several sonolucent regions were observed in the thyroid and in cases in which lymphocytic infiltration or fibrosis was observed sporadically, low-amplitude and uniform echoes were observed in the whole or several regions of the thyroid. In cases with no lymphocytic infiltration in the histological specimen, diffuse high-amplitude and uniform echoes were observed throughout the whole lobe of the thyroid. In patients with painless thyroiditis, the amplitude of echo was low when the level of lymphocytic infiltration was high and the echo-amplitude showed a tendency to increase along with the decrease in the rate of lymphocytic infiltration. From these observations it is concluded that echo-amplitude is well correlated with lymphocytic infiltration and fibrosis in patients with Hashimoto-thyroiditis, Hashitoxicosis and painless thyroiditis.