A simplified approach to minimally invasive parathyroidectomy

To assess the feasibility of a simplified approach for the use of a rapid intraoperative parathyroid hormone (IOPTH) assay based on a single 10-minute post-excision level using the workup parathyroid hormone level (wPTH) as the baseline in minimally invasive parathyroidectomy (MIP) and to compare the predictive value of this criterion with other recommended criteria.

Case series with chart review.

A single surgeon's prospectively maintained parathyroidectomy database at an academic center was reviewed over a 2-year period from June 2009 through June 2011.

A total of 102 patients undergoing MIP met the inclusion criteria. An IOPTH threshold of a ≥ 50% drop at 10 minutes post-excision from the wPTH baseline resulted in acceptable false positive (1.9%) and false negative (0.9%) rates. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of this modified criterion was 98.9%, 71.4%, 98%, 83.3%, and 97%, respectively.

In our patient cohort, the pre-incision and pre-excision IOPTH levels did not seem to change the overall accuracy of predicting surgical success in MIP if a single 10-minute post-excision IOPTH level is used along with the wPTH, and is commensurate with the commonly used Miami and Vienna criteria. A single intraoperative blood sample demonstrating a ≥50% drop from the wPTH at 10 minutes post-excision should be explored further as a feasible simplified criterion that avoids multiple IOPTH samples.