Evaluation of the extent of resection and detection of ischemic lesions with intraoperative MRI in glioma surgery: is intraoperative MRI superior to early postoperative MRI?

OBJECTIVEMRI scans obtained within 48–72 hours (early postoperative MRI [epMRI]), prior to any postoperative reactive changes, are recommended for the accurate assessment of the extent of resection (EOR) after glioma surgery. Diffusion-weighted imaging (DWI) enables ischemic lesions to be detected and distinguished from the residual tumor. Prior studies, however, revealed that postoperative reactive changes were often present, even in epMRI. Although intraoperative MRI (iMRI) is widely used to maximize safe resection during glioma surgery, it is unclear whether iMRI is superior to epMRI when evaluating the EOR, because it theoretically shows fewer postoperative reactive changes. In addition, the ability to detect ischemic lesions using iMRI has not been investigated.METHODSThe authors retrospectively analyzed prospectively collected data in 30 patients with glioma (22 and 8 patients with enhancing and nonenhancing lesions, respectively) who underwent tumor resection. These patients had received preoperati...