Intraoperative Cortical Sensorimotor Mapping During Glioma Resection Monitored With Drum Playing During Awake Craniotomy: A Case Report.

Tumors infiltrating the precentral gyrus remain a unique operative challenge. In this study, we explored a novel approach for awake craniotomy involving a patient playing a drum pad during resection of low-grade glioma, with the use of preoperative navigated transcranial magnetic stimulation (nTMS)-generated diffusion tensor imaging (DTI) and high-density real-time electrocorticography (ECoG). A 36-year-old left-handed male with a low-grade glioma in the left hemisphere hand knob region had a grand mal seizure. We combined preoperative nTMS-DTI with intraoperative passive functional mapping using high-density real-time ECoG. During an awake craniotomy, the patient played a drum pad while we assessed somatosensory-evoked potentials (SSEPs) using a 64-channel ECoG grid. This confirmed the absence of motor-evoked potentials (MEPs) over the tumor area, consistent with nTMS findings. Continuous monitoring of the patient's drum pad performance during the resection allowed for a gross total resection (GTR) of the tumor. Following the resection, he experienced some weakness in the intrinsic muscles of his right hand, which returned to full normal function at 6 months. At the end of 1 year, he remained seizure-free. A multimodal mapping strategy combined with awake monitoring of drum playing enabled preservation of function while achieving GTR in a patient with a motor-eloquent glioma.