Parathyroid exploration. A review of 125 cases.

Cervical exploration was performed in 106 patients with primary hyperparathyroidism and in 19 patients with chronic renal failure. Initial exploration for primary hyperparathyroidism was successful in 97% of the cases. Single adenomas were found in 84, double adenomas in six, and multiple-gland hyperplasia in 12 patients. Two of the four patients in whom cervical exploration failed were ultimately given the diagnosis of benign familial hypocalciuric hypercalcemia. Thirteen adenomas were ectopic. Preoperative thallium-technetium scans and ultrasound correctly localized only 63% of the adenomas. Only 45% of the ectopic adenomas were correctly localized. 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 searched carefully. Preoperative localization studies are not as reliable as an experience parathyroid surgeon.