To evaluate the effect of ⁹⁹Tc^m-methoxyisobutylisonitrile (⁹⁹Tc^m-MIBI) in intraoperative localization during parathyroidectomy for secondary hyperparathyroidism patients.

Clinical data of 33 patients who underwent parathyroidectomy for secondary hyperparathyroidism at the Department of Nephrology, Jiangsu Subei People's Hospital from February 2012 to September 2018 were reviewed retrospectively. Patients were divided into two groups according to operative method, namely, patients undergoing parathyroidectomy with ⁹⁹Tc^m-MIBI guidance (groupⅠ) and those undergoing parathyroidectomy without ⁹⁹Tc^m-MIBI guidance (groupⅡ). Operative time and complications were collected, and the remission rate, successful rate, recurrence rate, and pathological positive rate were calculated by biochemical indexes and pathological results. The t-test was used to compare the intra- and inter-group differences of operative time, blood calcium and phosphorus, and preoperative blood parathyroid hormone (PTH), non-parametric tests were used to compare the intra-and inter-group differences of postoperative blood PTH, and the Fisher's exact probability method was used to compare the differences of success, remission, short-term recurrence, and pathological positive rates.

There was no significant difference in operation time or complications between the two groups (P>0.05). The levels of serum calcium, phosphorus, and PTH in the two groups on the 1st day, 1st week, and 6th month after operation were significantly lower than those before operation (P<0.05). There was no significant difference in remission rate (100% vs 86.7%) or short-term recurrence rate (0% vs 7.69%) between groupsⅠandⅡ(P>0.05), although the successful rate of operation (100% vs 73.3%) and pathological positive rate (100% vs 92.7%) were significantly different between the two groups (P=0.033, P=0.033).

Compared with parathyroidectomy without ⁹⁹Tc^m-MIBI guidance, intraoperative ⁹⁹Tc^m-MIBI radio-guided parathyroidectomy for secondary hyperparathyroidism can achieve higher pathological positive rate and improve the successful rate of operation, and reduce the incidence of recurrence and complications theoretically by localizing the lesions more accurately. ⁹⁹Tc^m-MIBI guidance may replace intraoperative pathology to reduce the operative time and is an effective and feasible method for intraoperative localization during parathyroidectomy.