Parathyroid autotransplantation during thyroidectomy: is frozen section necessary?

OBJECTIVE To evaluate the accuracy of parathyroid gland identification and the need for routine frozen section examination before parathyroid autotransplantation during thyroidectomy. DESIGN A prospective case series. SETTING An endocrine surgical unit. PATIENTS From January 1, 1995, to December 31, 1997, parathyroid autotransplantation was attempted for devascularized or inadvertently removed glands in 152 (33.7%) of 450 patients during thyroidectomy. Before autotransplantation, a biopsy specimen of the transplanted tissue was sent for histological examination without frozen section confirmation. MAIN OUTCOME MEASURES Positive identification of parathyroid tissue in microscopic examination. RESULTS Of 179 attempted autotransplantations of parathyroid glands, parathyroid tissue was confirmed in 167 biopsy specimens (93.3%). Incorrect identification of parathyroid gland occurred in 12 instances. The tissue mistaken as parathyroid gland included fat in 6 cases, thyroid tissue in 4 cases, lymph node in 1 case, and thymus in 1 case. Transplantation of at least 1 parathyroid gland (range, 1-3) was confirmed in 144 patients. For patients with confirmed parathyroid autotransplantation at risk of hypoparathyroidism (n = 112), postoperative transient hypocalcemia occurred in 22 (19.6%), while no patient developed any permanent hypocalcemia during a median follow-up of 6 months. CONCLUSIONS Devascularized or inadvertently removed parathyroid glands can be identified expeditiously without routine frozen section during thyroid surgery. Immediate autotransplantation should be performed and permanent hypoparathyroidism can be avoided with this measure.