[Sonographic findings in autonomous adenoma of the thyroid gland in a goiter-endemic region].

Ultrasound scanning was carried out in 84 patients with autonomous nodules and 67 patients with inactive nodules. The echo pattern was correlated to the macro- and microscopic findings as well as to the function of the nodules. The autonomous nodules showed a low echogenicity in 57%, a normal parenchyma-identical echogenicity in 10% and a high echogenicity in 33%. In comparison the echo pattern of the inactive nodules showed low level echoes in 31%, normal in 36% and a high level echoes in 31%. Only one third of the nodules showed a homogeneous echo pattern, one third showed liquid degeneration and one third a mixed echo pattern. There is no correlation between the echo pattern of the autonomous nodules and the metabolic function of the nodules. 65 patients have been operated (37 autonomous and 28 inactive nodules). The macroscopic findings showed bleeding and cysts in most of the echo-poor nodules, also those with homogeneous structures. In the histological findings microfollicular structures were found in both high- and low-echogenicity nodules (18/16%). Macrofollicular changes and mixed forms were found mainly in nodules with parenchyma-identical and high echogenicity (58/48%). Ultrasound is very helpful in the morphological diagnosis of thyroid nodules, but there is no significant correlation to metabolic activity or to microscopic structures of the nodules in the thyroid gland.