Motor mapping to enable resections of peri-rolandic diffuse gliomas

Area of Science:

• Neurosurgery
• Neuro-oncology
• Brain mapping

Background:

• Intraoperative motor mapping is crucial for safe resection of peri-Rolandic gliomas.
• Comparative outcomes of awake versus asleep mapping across WHO 2021 molecular subtypes are not well-defined.
• This study compares awake and asleep motor mapping in glioblastoma (GBM) and IDH-mutant gliomas.

Purpose of the Study:

• To compare neurological outcomes between awake and asleep intraoperative motor mapping techniques.
• To evaluate outcomes across different glioma molecular subtypes (GBM and IDH-mutant).
• To assess the safety and efficacy of handheld probe direct cortical stimulation (HHP-DCS) versus subdural electrode direct cortical stimulation (SDE-DCS) within the asleep cohort.

Main Methods:

• Retrospective analysis of 130 patients with peri-Rolandic gliomas undergoing motor mapping.
• Stratification by mapping modality (awake vs. asleep) and tumor subtype (WHO 2021).
• Comparison of primary outcome (neurological deficits at 3 months) and secondary outcomes (KPS, survival).

Main Results:

• Comparable 3-month deficit rates between awake (5.6%) and asleep (5.3%) mapping.
• No neurological deficits observed in IDH-mutant glioma patients regardless of mapping modality.
• Similar progression-free and overall survival in GBM patients between awake and asleep mapping groups.

Conclusions:

• Awake and asleep motor mapping yield comparable neurological outcomes in glioma patients.
• Asleep motor mapping is a suitable alternative when awake craniotomy is not feasible.
• HHP-DCS and SDE-DCS appear comparable in terms of safety for asleep mapping.