Sonography of the thyroid and parathyroid.

Ultrasound is a primary imaging tool for thyroid and parathyroid localization. Classic thyroid and parathyroid tumors are easily distinguished by their sonographic appearance and location, but variations are common and complicate the distinction. Thus, biopsy under ultrasound guidance provides proof of the nature of the lesion. When parathyroid localization is problematic with ultrasound, magnetic resonance imaging is an excellent alternative.