Dual Localization with Ultrasound and Iodine 123 and Technetium (99mTc) Sestamibi Scintigraphy is Superior to Single Imaging Modalities in Facilitating Minimally Invasive Parathyroidectomy for Primary Hyperparathyroidism

Primary hyperparathyroidism is caused by a single parathyroid adenoma in the majority of patients. Localization of parathyroid adenomas prior to surgery has the benefit of allowing a minimally invasive approach. Over the years, multiple imaging modalities have been employed in an attempt to identify the site preoperatively, with varying degrees of success. In this study, we explore the accuracy of a combination of ultrasound and nuclear medicine planar scintigraphy with iodine-123 and technetium (99mTc) sestamibi. A retrospective study of consecutive series of 117 patients undergoing minimally invasive parathyroidectomy was carried out. Inclusion criteria incorporated clinical and biochemical evidence of primary hyperparathyroidism. All patients had at least one form of imaging: Ultrasound or nuclear medicine scintigraphy or both. The accuracy was compared with surgical findings. Gland weight was also related to imaging accuracy. A total of 101 patients underwent surgery for primary hyperparathyroidism. There was no significant difference between ultrasound and scintigraphy ability to localize a parathyroid adenoma (p = 0.738). The combination of ultrasound and scintigraphy was superior at preoperative localization compared to ultrasound (p = 0.039) or scintigraphy alone (p = 0.0078). Gland weight had no significant bearing on the accuracy of the scan (ultrasound, p = 0.89; scintigraphy, p = 0.16). Dual localization with ultrasound and scintigraphy in primary hyperparathyroidism is superior to a single imaging technique. Dual localization facilitates minimally invasive parathyroidectomy.