Ultrasonic appearance of adenomatous and hyperplastic parathyroid glands.

An investigation was made of the sonographic and histopathologic characteristics of 27 parathyroid adenomas and 11 primary and secondary hyperplastic parathyroid glands demonstrated by ultrasound before surgical confirmation. All the hyperplastic glands and 21 of the adenomas had a homogeneously sonolucent interior structure and a smooth periphery. The adenomas and hyperplastic glands were sonographically indistinguishable except for 5 large adenomas which had areas of varying echodensity and an irregularly nodulated periphery. The ultrasonically inhomogeneous adenomas were histopathologically more heterogeneous with asymmetric, nodular enlargement. One patient had a cystic adenoma. The results are discussed in relation to the ultrasonic appearance of thyroid noduli and lymph nodes being the main source of errors in parathyroid ultrasonography.