A Simple Scoring System to Predict the Resectability of Skull Base Meningiomas via an Endoscopic Endonasal Approach

To identify clinico-radiologic factors associated with incomplete anterior cranial fossa (ACF) meningioma resection via an endoscopic endonasal approach.

Patients undergoing endoscopic endonasal resection of an ACF meningioma were retrospectively accrued from two university-affiliated centers. Demographic profiles and radiologic findings, including tumor dimensions and morphology, anatomic location, and vascular involvement, were stratified according to the extent of resection.

Twenty-five patients were included in this study. Factors associated with incomplete surgical resection via an endonasal route were: presence of hyperostosis (P = 0.04), cavernous internal carotid artery involvement (P = 0.001), maximal dural tail length in the transverse plane (P = 0.006), and its ratio to the inter-fovea ethmoidalis distance (P = 0.01). Using a multiple regression analysis, only cavernous internal carotid artery involvement (P = 0.002) and a large dural tail length to inter-foveal distance ratio (P = 0.04) were significant predictors of incomplete resection (multiple correlation coefficient = 0.71). The combination of predictive factors to determine the likelihood of complete endoscopic resection produced a scoring system with a sensitivity and specificity of 85.7% (95% confidence interval [CI], 42.1-99.6] and 100% (95% CI, 81.5-100), respectively.

The use of a simple scoring system outlined in our study can facilitate proper patient selection for endoscopic endonasal resection of ACF meningiomas.