Asleep motor mapping in resected low-grade gliomas -a population based multicenter study

Area of Science:

• Neurosurgery
• Oncology
• Radiology

Background:

• Maximal safe resection is a key goal for WHO grade 2 low-grade gliomas (LGG).
• Asleep motor mapping is an emerging alternative to awake surgery for tumors near critical motor areas, demonstrating safety and efficacy in expert centers.

Purpose of the Study:

• To identify predictors of postoperative motor deficits in patients undergoing asleep motor mapping for LGG.
• To describe patient selection and intraoperative mapping techniques used across Scandinavian neurosurgical centers.

Main Methods:

• Retrospective analysis of 74 patients (≥18 years) with WHO grade 2 gliomas who underwent asleep motor mapping across eight Scandinavian institutions.
• Data collected included clinical, surgical, and imaging variables, with a primary outcome of permanent postoperative motor deficits at 3 months.
• Logistic regression analysis was used to assess associations with pre-, intraoperative, and radiological variables, including diffusion-weighted imaging (DWI) changes.

Main Results:

• Permanent postoperative motor deficits occurred in 25.7% of patients (19/74), with 6.8% considered major deficits.
• Univariate analysis revealed significant associations between preoperative motor deficits, postoperative DWI changes, and age with permanent deficits.
• Multivariate logistic regression confirmed DWI changes and age as significant predictors of permanent motor deficits.

Conclusions:

• Postoperative motor deficits are relatively common following asleep motor mapping for low-grade gliomas.
• Preoperative motor deficits and diffusion-weighted imaging changes are significant predictors of permanent motor deficits in this patient population.