2026 Poster Presentations
P312: BRAINSTEM CAVERNOUS MALFORMATION SURGICAL OUTCOMES USING ENDOSCOPIC-ASSISTED APPROACHES: A SINGLE-ARM META-ANALYSIS OF SAFETY AND EFFICACY
Khushal Gupta, MBBS1; Michael Karsy, MD, PhD, MSc, FAANS, FCNS2; 1Bharat Ratna Late Shri Atal Bihari Vajpayee Memorial Medical College; 2University of Michigan Health
Background: Brainstem cavernous malformations (BSCMs) are among the most challenging neurosurgical lesions because of their deep location and close relationship with critical neural pathways. Surgical treatment carries substantial risks, yet leaving them untreated may result in devastating hemorrhages. In recent years, endoscopic-assisted approaches have been proposed to improve visualization and minimize brainstem manipulation. We performed a systematic review and meta-analysis to better define the safety and effectiveness of this evolving strategy.
Methods: Following PRISMA guidelines, PubMed, Embase, and Scopus were searched through July 2025. We included clinical studies reporting outcomes of patients who underwent endoscopic-assisted resection of BSCMs; case reports with fewer than five patients were excluded. Two reviewers independently extracted study and patient data into a structured database. The primary endpoints were gross total resection (GTR), new cranial nerve (CN) deficits, CSF leak, recurrence or rebleed, neurological improvement, and functional independence. Random-effects models were applied, and pooled proportions were calculated using the Freeman–Tukey double arcsine transformation. Heterogeneity was assessed with I² and τ² statistics.
Results: Three studies comprising 29 patients were included, with an average follow-up of 28.4 months. The pooled GTR rate in this small series was 96% (95% CI 83–100), while subtotal resection occurred in 7%. New or worsened CN deficits were observed in 19% (95% CI 5–38), and postoperative CSF leak occurred in 22% (95% CI 0–58). No cases of recurrence or rebleed were reported during follow-up. Perioperative mortality was low at last follow-up. Most patients demonstrated improvement in neurological function and maintained functional independence. Across outcomes, heterogeneity was minimal, indicating consistency in reported results despite limited sample size.
Conclusions: This pooled analysis indicates that endoscopic-assisted surgery for BSCMs may allow for high rates of resection in selected cases, but postoperative cranial nerve deficits and CSF leaks remain notable risks. Given the very small number of patients and studies available, these findings should be interpreted cautiously. At present, the technique remains relatively unproven, and its role compared with conventional microsurgery is not yet established. Larger, multicenter prospective series with standardized outcome measures are needed to clarify long-term safety, durability, and optimal patient selection before stronger conclusions can be drawn.
