gms | German Medical Science

Objective: Although extensive resection is a prognostic factor in gliomas, it must not be attempted at the cost of neurological deterioration. The aim of this study was to assess whether the use of an intraoperative MRI (iMRI) in combination with neurophysiological monitoring (IOM) is suitable to improve the extent of resection without endangering neurological function in patients with eloquently located gliomas.

Methods: We analyzed data on all consecutive glioma patients undergoing iMRI-guided surgery in combination with IOM techniques including continuous registration of motor and sensory evoked potentials as well as direct cortical and subcortical stimulation. We evaluated the extent of tumor resection with early postoperative high field MRI and determined the clinical status of patients 7 days after surgery.

Results: 54 patients were included in this study. In 21 patients (38.9%), intraoperative imaging led to additional tumor resection. Radiologically complete resections were achieved in 31 patients (57.4%), while in 12 of these iMRI, had depicted residual tumor tissue before resection was continued. In all other cases, IOM findings prohibited further tumor resection. Postoperatively, 13 patients (24.1%) showed new or worsening of pre-existing sensory-motor deficits. They were severe in 4 patients (7.4%). There was no correlation between the occurrence of either any new (P=0.77) or severe (P=1.0) sensory-motor deficit and continued resection after intraoperative image acquisition. Likewise, tumor location, histology, and tumor recurrence did not influence the complication rate.

Conclusions: The combination of iMRI-guidance with multimodal neurophysiological monitoring allows for extended resections in glioma surgery without inducing higher rates of neurological deficits, even in patients with eloquently located tumors.