Awake Craniotomy for Eloquent Brain Arteriovenous Malformations: A Systematic Review and Individual Patient Data Meta-Analysis

Background: Arteriovenous Malformations (AVMs) pose a risk of neurologic deterioration, particularly when located in eloquent areas. While awake surgery is well-established for treating low-grade gliomas near eloquent areas, its efficacy for AVMs is less conclusively reported.

Methods: This study conducted a systematic review and individual patient data (IPD) meta-analysis following Cochrane Collaboration and PRISMA guidelines. Literature searches were performed in Pubmed, Embase, and Web of Science. Eligible studies included case reports, case series, retrospective or prospective cohorts, and randomized trials evaluating Awake Craniotomy (AC) for AVMs. Single proportion analysis with 95% confidence intervals (CI) was utilized to pool the data. Case series and case reports were put together as a unique cohort.

Results: An analysis of 20 studies encompassing 287 patients was performed. The IPD cohort had 53 patients. The primary outcome pooled analysis indicated an 88% (CI 95% 81-95%; I2=63%) rate of total resection. Moreover, a rate of nearly 12% (CI 95% 5-19%; I2= 63%) of subtotal resection was observed. Furthermore, the analysis unveiled a 20% (95% CI, 13-28%; I2=58%) rate of postoperative neurological deficits, alongside a 6% (95% CI, 3-9%; I2=29%) rate of follow-up neurological deficits. The mean hospital stay was 4.13 (95% CI: 3.61-4.66; I2=73%) days.

Conclusion: Awake craniotomy for eloquent AVMs showed promising results. A significant rate of postoperative neurological deficits was found, which was reduced at follow-up. A small mean length of hospitalization was also found. These results suggest that AC for AVMs should be considered in eloquent lesion cases.