Intraoperative Navigated Three-Dimensional Ultrasound Guidance Improves Resection in Gliomas Compared with Standard Two-Dimensional Ultrasound-Results from a Comparative Cohort Study.

Objective: Intraoperative ultrasound is a promising tool for intraoperative tumor resection control. Navigated three-dimensional US (n3DUS) has many benefits over standard two-dimensional US (2DUS).

Methods: Two cohorts (2DUS and n3DUS) of patients with histologically confirmed adult diffuse gliomas undergoing US-guided resection control were compared. The primary outcomes assessed were extent of resection and morbidity. Multivariate analysis was performed to account for tumor characteristics (delineation and eloquence) and surgeon experience, which could confound the results.

Results: n3DUS was used more often (n = 252) than 2DUS (n = 86). Tumor delineation was similar in 2DUS and n3DUS cohorts, although the n3DUS cohort included more nonenhancing, histologically lower grade (2-3) gliomas and had more gliomas located in eloquent regions; also, n3DUS was more often used by senior surgeons. Gross total resection (GTR) rates were 47%, and major morbidity was 9.5%. On multivariate analysis, after controlling for all other variables between the 2 groups, patients with well-delineated tumors, patients with prior treatment, and patients who underwent n3DUS were more likely to have GTR (adjusted odds ratios 3.0, 1.8, and 2.2, respectively), whereas patients with tumors in eloquent locations were half as likely (adjusted odds ratio 0.5) to have GTR. Eloquent located tumors were likely to be associated with higher neurological morbidity, although major morbidity was not significantly different.

Conclusions: Good delineation, noneloquent location, and use of n3DUS was associated with a higher probability of GTR in glioma surgery. Surgeons' experience did not influence the extent of resection. Morbidity was predominantly associated with eloquent location, independent of all other factors.