Preoperative Localization Of Sensorimotor Cortex: MRI versus MEG

Accurate knowledge of cortical functional organization is important in the surgical treatment of brain disorders, because the relevant pathology is often within, or adjacent to, cortical regions that are critical for essential sensory, motor, or cognitive functioning. Avoidance of sensorimotor cortex is especially important because damage to this area can cause a hemiparalysis that reduces the quality of a patient’s post-operative life. It is well established that the central sulcus normally demarcates the boundary between primary motor and somatosensory areas, but presurgical identification of the central sulcus by magnetic resonance imaging (MRI) can be difficult, especially in neurosurgical patients where lesions can cause significant distortion of the local neuroanatomy. The present study compared central sulcus identifications using MRI versus MEG in patients that underwent subsequent intraoperative monitoring for validation of preoperative inferences.