[Neurophysiological monitoring during surgery for astrocytoma at the motor strip with awake craniotomy].

We present a case of a 26-year-old male with fibrillary astrocytoma at the right face motor cortex. Surgery was performed with the patient under propofol anesthesia. Stimulation mapping techniques for localization of the motor and sensory cortex were applied. The entire right face motor cortex was resected up to the hand region, resulting in a gross total removal of the tumor. Postoperatively, the patient only had transient weakness of the left lower face. For improving the prognosis of gliomas around the motor strip, it is necessary to resect the tumor as much as possible while preserving motor function. Preoperative understanding of the anatomical relationship between the tumor and the motor strip, and intraoprative neurophysiological monitoring may be necessary. In order to simulate the operative fieled preoperatively, we superimposed the superficial venous image obtained by magnetic resonance angiography (MRA) upon the surface anatomy scan (SAS). Magnetoencephalography (MEG) provided precise localization of the central sulcus, preoperatively. The methods of direct cortical stimulation to localize sensorimotor pathways with awake craniotomy enabled us to resect the tumor maximally and to minimize morbidity.