Improvement of presurgical patient evaluation by generation of functional magnetic resonance risk maps

Recent functional magnetic resonance imaging (FMRI) replication studies sho w a high variability of active voxels within subjects and across runs - a p otentially harmful situation for clinical applications. We tried to reduce these uncertainties inherent in current presurgical FMRI. For this, a new h igh quality head fixation device was used to detect reliably activated voxe ls over repeated measurements. In addition high correlation thresholds were applied to define the areas with highest probability of activation. The re sults show a focussing of such functional high risk areas to only a few vox els which localized close to intraoperative cortical stimulation. The gener ation of such FMRI risk maps may improve validity of clinical localization and facilitate the development of currently missing standards for maximized but sti II safe tumor resection. (C) 2000 Elsevier Science Ireland Ltd. Al l rights reserved.