Tc99m Sestamibi Scan in Parathyroid Surgery: Positive Scan Obviates Routine Intra‐operative Parathormone Monitoring

Abstract

Objectives: Parathyroid surgery for hyperparathyroidism has moved from traditional four gland exploration to a minimally invasive procedure with advent of better imaging tools, intraoperative parathyroid hormone (PTH0 monitoring, and endoscopic techniques. In our hospital parathyroid operation is accomplished with preoperative sestamibi and serum PTH monitoring at D1 post-op. Intra-operative PTH assay is done only in selected patients. Methods: Analyze the outcome of parathyroid surgery at our hospital and correlate pre-operative sestamibi localisation of adenoma with operative findings. Retrospective chart review of 40 patients who had parathyroid operations from 2009 to 2012. Results: The majority of referrals came through GP and were seen at Joint Endocrinology and ear, nose, and throat (ENT) clinic but there were occasional referrals from renal, urology, orthopedics and surgical admissions. Half presented with incidental hypercalcemia and other half had varied clinical presentations like calculi, renal failure, fractures, fatigue, dehydration, acute abdomen etc. Majority (30/40) were females. Age ranged from 22 to 88 with mean of 58. Average operating time was 50 minutes with incision length from 2.5 to 4 cms. Two patients needed 2nd exploration. Postoperative PTH and calcium levels returned to normal in 38/40 patients. 36 had sestamibi scan and localization was positive in 24/36 patients (66.6%) and correlated 100% with surgical findings. In patients with negative scan, 4 gland explorations were done. Inferior gland pathology was found in two thirds with left inferior in majority. Conclusions: In our view, a preoperative sestamibi scan is sufficient in majority of patients. 4 gland explorations with intraoperative PTH assay are useful in selective patients with negative scan.