Brain tumor resection: Intraoperative monitoring with high-field-strength MR imaging-initial results

PURPOSE: To investigate the challenges and benefits of magnetic resonance ( MR) imaging during brain tumor resection. MATERIALS AND METHODS: A short-bore 1.5-T MR system equipped with echo-plan ar-capable gradients was used in resection of brain tumors in 30 patients. MR sequences and need for contrast material enhancement were determined on the basis of the targeted lesion. MR images were acquired before, during, a nd after surgery. Tissue obtained at biopsy or excised as a result of intra operative MR findings was examined histopathologically. RESULTS: MR images of enhancing lesions proved to be the most challenging t o interpret intraoperatively, and relative enhancement at the resection cav ity boundary was not specific for residual tumor. The ability to detect res idual tumor intraoperatively resulted in a radiologically complete resectio n in 24 (80%) of 30 patients. The frequency of complications was low, and n o untoward effects related to the MR environment were observed. CONCLUSION: Intraoperative MR imaging provided valuable information on the completeness of resection, and resection progress was well demonstrated dur ing surgery.