Preoperative Embolization vs. Direct Surgery in Skull Base Meningiomas: A Systematic Review and Meta-Analysis with Meta-Regression

Abstract

• This is the largest meta-analysis to date comparing preoperative embolization (POE) versus direct surgery in skull base meningiomas, including 896 patients across 21 studies. • POE did not significantly reduce intraoperative blood loss, operative time, transfusion rate, or postoperative complication rates compared with direct surgery. • Meta-regression and subgroup analyses confirmed the findings were robust, showing no significant influence from modifiers like year, sample size, or Simpson grade. • The results were confirmed as robust by comprehensive sensitivity analyses (LOO and Baujat plots) and confirmed as free of publication bias (funnel plots/Egger's test). • Findings suggest that routine preoperative embolization offers limited benefit and should be reserved for highly vascular or giant skull base meningiomas after multidisciplinary evaluation. Skull base meningiomas present unique surgical challenges due to proximity to critical neurovascular structures, leading to prolonged operative time, significant blood loss, and high complication risks. Preoperative embolization (POE) is used to reduce tumor vascularity and potentially decrease blood loss and operative time. However, existing studies are limited by small samples and a general focus, particularly lacking robust evidence for skull base lesions. We aimed to perform a systematic review and meta -analysis of the efficacy of POE versus direct surgery in skull base meningiomas. A systematic search from inception up to 30 July 2025 (PubMed, Embase, and Cochrane Central) identified studies comparing POE to direct surgery for skull base meningiomas. Outcomes included intraoperative blood loss, operative time, hemoglobin, complications, and transfusion rates. Statistical analysis used a frequentist random-effects model (Risk Ratios [RR], Mean Differences [MD]), with heterogeneity assessed via I 2 and the Cochrane Q test. Twenty-one studies (n = 896; mean age 54, 65.5% females), including 349 POE patients (39%), were analyzed. Pooled analysis revealed no statistically significant differences between POE and direct surgery for intraoperative blood loss (MD −67.26; 95% CI [-265.28; 130.76]; p = 0.51; I 2 = 98.4%), operative time (MD −0.30; 95% CI [-1.03; 0.42]; p = 0.42; I 2 = 87.8%), hemoglobin levels (MD 0.21; 95% CI [-0.54; 0.96]; p = 0.58; I 2 = 70%), blood transfusion rate (RR 0.89; 95% CI [0.65; 1.23]; p = 0.446; I 2 = 21%), or complication prevalence (RR 1.12; 95% CI [0.67; 1.87]; p = 0.637; I 2 = 25.7%). Subgroup analyses (Simpson grade, extent of resection) and meta -regression showed no significant effect modifiers. POE of skull base meningiomas did not significantly improve perioperative outcomes compared with direct surgery. Routine use may offer limited clinical benefit. Selective use may be warranted in giant or highly vascular tumors, but further high-quality studies are needed to confirm these findings.