Parathyroid update: a review of 220 cases.

A total of 220 patients have undergone cervical exploration for hyperparathyroidism by the author. A review of 125 cases was published in 1991. An additional 95 patients have been explored in the subsequent four years. Subtotal parathyoidectomy was performed in 39 patients with chronic renal failure. Exploration was successful in over 97% of the 181 patients diagnosed with primary hyperparathyroidism. Single adenomas were found in 146, double adenomas in 11, and multiple gland hyperplasia in 19 patients. Two of the five patients in whom cervical exploration failed were ultimately diagnosed with benign familial hypocalciuric hypercalcemia. Twenty-four adenomas were ectopic. Preoperative thallium-technetium scans and ultrasound correctly localized only 61% of the adenomas. Technetium sestamibi scans were correct in two of four adenomas. Only 47% of ectopic adenomas were correctly localized by isotope scanning and 29% by ultrasound. All four glands should be examined at initial exploration. Because of the occurrence of double adenomas, contralateral exploration is always indicated regardless of whether an enlarged gland and a normal one are found on the first side. All enlarged parathyroids should be removed when dealing with single or multiple adenomas; subtotal parathyroidectomy (3-1/2 glands) should be performed in multiple gland hyperplasia. Frozen section confirmation of excised parathyroid tissue is essential. If exploration is unsuccessful, ectopic locations, such as the retroesophageal areas, thymus, anterior and posterior mediastinum, carotid sheath and thyroid lobe, must be examined carefully. Preoperative localization studies are not as reliable as an experienced parathyroid surgeon.