Intraoperative ultrasound and reoperative parathyroid surgery: An initial evaluation

We compared intraoperative ultrasound (IOUS) to preoperative high-resolution real-time ultrasound in 25 consecutive patients undergoing reoperations for primary hyperparathyroidism. Intraoperative neck scanning was performed after the platysma muscle flaps were raised, and one or both sides of the neck were opened along the medial border of the sternocleidomastoid muscle. Preoperative localization studies were used to determine which side of the neck to explore. Pathologic parathyroid glands appeared sonolucent on both pre- and intraoperative ultrasound. Glands were always imaged in 2 planes. Neither preoperative nor intraoperative scans were able to image normal parathyroid glands. Preoperative scans were correct for abnormal tissue in 9 patients, and intraoperative scans were correct in 19 patients (p=0.01). Size of a pathologic parathyroid gland was not a factor in the ability of IOUS to detect it, but location was. Intrathyroidal and inferior glands were detected reliably, but superior glands were missed (33%). If IOUS imaged the pathologic parathyroid tissue, the length of the surgical procedure was significantly reduced [5.9 hours versus 3.1 hours (p= 0.005)]. IOUS did not appear to impact on ultimate outcome as 5 of 6 patients in whom IOUS failed to image the pathologic gland had successful surgery without complication.