Preoperative matching studies in the diagnosis of parathyroid adenoma for primary hyperparathyroidism: Can we avoid intraoperative PTH monitoring?

INTRODUCTION

We aim to determine the utility of intraoperative parathyroid hormone (IOPTH) monitoring in patients with matching preoperative ultrasound and mibi SPECT for primary hyperparathyroidism for a single adenoma.

METHODS

All patients who underwent minimally invasive parathyroidectomy (MIP) for pseudohypoparathyroidism (PHP) for a single parathyroid adenoma, were included. An Ultrasound and mibi SPECT were performed in all patients. We defined matching studies when both coincided in the localization of the adenoma. IOPTH was performed in all patients and analyzed in three occasions: a baseline measurement at the anesthetic induction, immediately before, and 15 minutes after gland excision. Success was defined during the third measurement as a drop of IOPTH of at least 50%compared to the previous maximum value after gland excision. Demographics, intraoperative, postoperative variables and the utility of IOPTH monitoring were analyzed.

RESULTS

A total of 218 MIP were performed. The average age was 60.1 years and 85% were female. Preoperative ultrasound and mibi SPECT coincided 100%. When the adenoma was localized, 15 minutes after its excision, IOPTH did not decrease in 9 patients (4.2% OR 1.9% - 7.69%); all of them underwent a bilateral neck exploration. The added-value of IOPTH accuracy for disease cure was 3.6%. There was a 99% of cure rate. The mean surgical time was 66.4 minutes and the waiting time for the third IOPTH result was 31minutes. Performing IOPTH monitoring made the surgery about twice more expensive.

CONCLUSIONS

Preoperative matching ultrasound and mibi SPECT for parathyroid adenoma localization in PHP, could avoid IOPTH monitoring in minimally invasive parathyroidectomies.