Preservation of Motor Function After Resection of Lower-Grade Glioma at the Precentral Gyrus and Prediction by Presurgical Functional Magnetic Resonance Imaging and Magnetoencephalography.

BACKGROUND: Intra-axial brain tumors located at anatomically eloquent areas are challenging conditions. On one hand, it is often difficult to pursue maximum extent of resection of tumor in these locations. On the other hand, neuroplasticity occurs in some patients with low-grade glioma, and the primary neural functions are known to sometimes shift from conventional "eloquent cortices."

CASE DESCRIPTION: In a patient with a lower-grade glioma located at the precentral gyrus, shift of primary motor function from the precentral gyrus to the postcentral gyrus was detected on magnetoencephalography and functional magnetic resonance imaging. Aggressive removal of the pathologic precentral gyrus was accomplished via awake craniotomy without causing obvious motor function deficit.

CONCLUSIONS: This case highlights the importance of preoperative multimodal neurophysiologic imaging in patients with low-grade gliomas in eloquent areas.