[Diagnostic imaging of the thyroid].

Among various imaging modalities used for the diagnosis of thyroid diseases, ultrasonography is the most sensitive and economical method to visualize anatomic detail and structural relations. Scintigraphy using 123I or 99mTc gives critical information about thyroid cell function and makes it possible to differentiate the causes of thyrotoxicosis. Tumor scintigraphy using 201T1, 67Ga, 131I-metaiodobenzyl guanidine or 99mTc(V)-dimercaptosuccinic acid is useful for the characterization of nodules. Recently introduced magnetic resonance imaging appears promising in demonstrating pseudocapsules around tumors and capsular invasion.