Utility of Intraoperative Ultrasonography for Resection of Pituitary Adenomas: a Comparative Retrospective Study

Background: The evolution of pituitary surgery has made it a safe and effective form of treatment; however, risks of inadequate tumor resection, cerebrospinal fluid (CSF) leak, pituitary dysfunction, and vascular injury still exist. The use of intraoperative ultrasonography (IOUS) in pituitary surgery has been well described. Recent advancements in ultrasound technology have allowed for expanded utility as described here.

Methods: A retrospective review was performed between January 2016 and December 2019. One hundred thirty-eight patients (mean age 53.7 years, 47% females) were identified undergoing transsphenoidal surgery for pituitary tumors. Thirty-four patients had IOUS performed using a side-firing ultrasound probe, while 104 did not. Data was analyzed for preoperative (demographics, clinical, and radiographic features), perioperative (blood loss, operative time), and postoperative (complications, length of stay, hormone remission, and extent of resection) outcomes.

Results: There were no significant differences in patient age, gender, tumor volume, Knosp grade, and hormone-secreting status between the two groups. Patients treated using IOUS had significantly higher rates of gross total resection (79% vs. 44%, p = 0.0008), shorter operative times (74 vs. 146 min, p < 0.0001), lower blood loss (119 vs. 284 cc, p < 0.0001), and hospital stays (2.9 vs. 4.2 days, p = 0.001). Overall complication rates were lower in the IOUS group compared to standard pituitary surgery but did not reach significance.

Conclusions: Recent improvements in ultrasound technology have allowed for miniaturization of probes capable of delivering high-resolution images. The use of IOUS in transsphenoidal pituitary surgery may significantly increase rates of gross total resection, while decreasing blood loss, hospital LOS, and operative time.