A meta-analysis of proportions of single arm observational series for anterior skull base meningiomas comparing supraorbital craniotomy to the endoscopic endonasal approach

Introduction: Olfactory groove (OG) and planum sphenoidale/tuberculum sella (PS/TS) meningiomas are frequently treated via supraorbital craniotomy (SOC) or endoscopic endonasal approach (EEA). Though previously compared, noncomparative studies comprising the majority of case series were excluded or analyses did not weight the study by sample size. We perform a meta-analysis taking these into consideration to understand relevant outcomes. Methods: A systematic literature search was performed from January 2000 to January 2020 for meningiomas treated by SOC or EEA utilizing PRISMA guidelines. Data was collected as binary variables. A meta-analysis of proportions for single-arm observational studies was performed in RStudios. Results: A total of 42 studies were included consisting of 427 SOC and 524 EEA patients. In OG, SOC had greater gross total resection (GTR; 90% [95% CI 84-94]) than EEA (66% [55-75]) (p < 0.0001 with a slight advantage in PS/TS (82% [76-87]) over EEA (74% [69-79]) (p = 0.0542). EEA had more frequent CSF leak in both OG (EEA 31%[22-41], SOC 11% [7-17], p = 0.0003) and PS/TS (EEA 15% [11-20], SOC 6% [4-10], p = 0.0020). Visual improvement was borderline significant (p = 0.0468) for EEA (73% [65-79]), over SOC (61% [51-70] given the overlapping confidence intervals. There was no difference in stroke, seizure, or recurrence. Discussion: SOC is favored over EEA for OG meningiomas given the higher rate of GTR and lower CSF leak rate. For PS/TS meningiomas without visual deficit, there is a slight EOR advantage with SOC. In cases of visual deficit, EEA has a slight advantage in postoperative visual improvement.