[Evaluation of ultrasonography in the diagnosis of thyroid nodules].

Purpose of the paper: Specify the merits of ultrasonography in thyroid pathology. Outline ultrasonographic orienting criteria to identify the nature of thyroid nodules. Analysis of the paper: Thyroid ultrasonography allows detecting nodules that cannot be detected clinically or with radionuclide scanning. 20% of sonographic nodules cannot be palpated; 33% of sonographic nodules are not visible on radionuclide scans. Ultrasonography often shows multiple nodules where palpation and/or radionuclide scanning detect only one. When there are clinical signs of hyperthyroidism and uncertain biological findings, ultrasonography can relate a low-uptake nodule with an adenoma becoming autonomous, if the nodule appears to be hypodense. It allows monitoring the volume of nodules under freination therapy. Benign nodules may be liquid (15.7% of all cases); solid and isoechogenic (27.6%); solid and hyperechogenic (10.1%); solid and hypoechogenic (18.1%, including 88.5% toxic adenomas) or compound (26.4%). Comparison of the 2 series of nodules reveals the predominance of liquid and iso/hyperechogenic solid appearances for benign nodules (63.8%, excluding toxic adenomas). For cancers, the frequency of hypodense solid or compound nodules is 92.2%. Combining radionuclide scanning and ultrasonography allows further restricting the group of suspicious nodules, which have a low uptake and are hypodense or compound.