Comparison between single-photon emission computed tomography/computed tomography and ultrasound in preoperative detection of parathyroid adenoma: retrospective review of an institutional experience.

Objective: The aim of this study was to evaluate the accuracy of technetium- 99m-methoxyisobutylisonitrile (Tc-MIBI) single-photon emission computed tomography/computed tomography (SPECT/CT) and ultrasound in preoperative localization of single parathyroid adenomas (PTAs) in patients with primary hyperparathyroidism (pHPT) who would be suitable for minimally invasive parathyroidectomy (MIP).
Methods: A retrospective study of 143 consecutive patients with biochemical evidence of hyperparathyroidism who underwent preoperative localization of parathyroid lesions using Tc-MIBI SPECT/CT and ultrasound, and proceeded to parathyroid surgery at our institution from January 2013 to January 2018. Of these, 125 had single adenomas and are the subject of this study. The sensitivity, positive predictive value (PPV) and accuracy of the two imaging techniques for the accurately identification and lateralization of PTAs were determined using histopathology as the criterion standard.
Results: Of 125 PTAs, the correct identification and lateralization were significantly higher by SPECT/CT than ultrasound. SPECT/CT and ultrasound detected lesions with histopathologically proven PTAs in 116 and 95 patients, respectively. The sensitivity, PPV and accuracy were 92.17, 94.64 and 87.60%, respectively, for SPECT/CT and 75.89, 90.43 and 70.25%, respectively, for ultrasound in lateralization analysis.
Conclusions: The results of our study indicate that Tc-MIBI SPECT/CT is more accurate than ultrasound for the preoperative identification of single PTAs in patients with pHPT who are candidates for MIP.