Ultrasonography of the thyroid and parathyroid glands.

High-resolution thyroid and parathyroid ultrasonography can play an integral part in the diagnosis and management of patients with clinically undifferentiated cervical masses, thyroid carcinomas or adenomas, and primary parathyroid hyperplasia or neoplasia. Because the study is inexpensive, noninvasive, and easily performed, ultrasonography can be performed as a screening test early in the evaluation of a patient, and ultrasound findings can corroborate the results of other diagnostic procedures, leading to a more accurate diagnosis.