The Efficacy of Low and High Dose 99mtc-MIBI Protocols for Intraoperative Identification of Hyperplastic Parathyroid Glands in Secondary Hyperparathyroidism

Abstract

Objective: The aim of this study was to compare the efficacy of low- and high-dose Tc-99m-MIBI protocols for intraoperative identification of hyperplastic parathyroid glands via gamma probe in secondary hyperparathyroidism.

Material and Methods: This retrospective study was conducted using a prospective database of 59 patients who had undergone radioguided subtotal parathyroidectomy between 2004-2012. The patients were studied in 2 groups. Group 1 (n=31) received 37 MBq Tc-99m-MIBI intravenously in the surgical room approximately 10 mm before the beginning of the intervention and surgery was performed under gamma probe guidance. Group 2 (n = 28) received 555 MBq Tc-99m- MIBI intravenously 2 h before surgery, which was also performed under gamma probe guidance. Intraoperative gamma probe findings, laboratory findings, and histopathological findings were evaluated together.

Results: Using acceptance of the histopathological findings as gold standard, sensitivity and specificity of intraoperative gamma probe for identifying hyperplastic parathyroid glands was 98% and 100%, respectively, in both groups.

Conclusions: In the light of these findings, it is concluded that the low-dose Tc-99m-MIBI protocol might be preferable for intraoperative identification of hyperplastic parathyroid glands in secondary hyperparathyroidism patients because it was observed to be as effective as the high-dose Tc-99m-MIBI protocol. Furthermore, the low-dose protocol does not have the disadvantages that are associated with the high-dose protocol. (C) 2014 Elsevier Espana, S.L. and SEMNIM. All rights reserved.