Background/Objective: Intracranial arteriovenous malformations (AVMs) are high-flow cerebrovascular lesions associated with a significant risk of intracranial hemorrhage, neurological morbidity, and mortality. Current management strategies, including microsurgical resection, endovascular embolization, stereotactic radiosurgery, and conservative observation, remain limited by procedural risk and uncertain long-term outcomes. Beta-blockers, particularly propranolol, have recently attracted interest as potential adjunctive therapies because of their vasoconstrictive, antiangiogenic, and vascular remodeling properties. This review evaluates the mechanistic rationale and current evidence regarding beta-blocker use in intracranial AVMs. Methods: A comprehensive literature review was conducted using PubMed, Scopus, and Google Scholar databases through January 2026 using combinations of the terms “arteriovenous malformation,” “AVM,” “beta-blocker,” “propranolol,” “angiogenesis,” “hemorrhage,” and “cerebral cavernous malformation.” Eligible studies included experimental investigations, translational studies, observational cohorts, case reports, clinical trials, systematic reviews, and meta-analyses evaluating beta-blocker use in intracranial AVMs or related vascular malformations. Studies unrelated to cerebrovascular lesions, duplicate reports, and non-English publications were excluded. Given the heterogeneity and limited volume of available AVM-specific literature, findings were synthesized narratively rather than through formal systematic review methodology. Discussion: Preclinical studies suggest that beta-blockers modulate molecular pathways implicated in AVM pathophysiology, including VEGF, HIF-1α, SDF1α/CXCR4, MMP-9, and Notch-associated signaling. These mechanisms may reduce abnormal angiogenesis, endothelial instability, and pathological vascular remodeling. Clinical evidence, however, remains limited to retrospective studies, perioperative reports, and indirect evidence from cerebral cavernous malformations. Observational studies have reported associations between beta-blocker exposure and certain favorable AVM characteristics, including lower rates of hemorrhagic presentation and less complex angioarchitecture. However, these findings are highly susceptible to confounding, reverse causation, and selection bias and should not be interpreted as evidence of disease modification. Conclusions: Beta-blockers cannot currently be recommended as definitive therapy for intracranial AVMs. Their established role remains perioperative hemodynamic control, while potential disease-modifying effects require validation through prospective studies and randomized clinical trials.

Background/Objectives: Expanded endoscopic endonasal approaches (EEAs) provide direct ventral access to adult intradural skull base tumors; however, postoperative complications are variably defined and reported in the literature. This review aimed to synthesize the overall spectrum of adult intradural EEA complications and distinguish pathology-specific evidence from large mixed EEA complication cohorts. Methods: A PRISMA 2020 systematic review and meta-analysis searched PubMed/MEDLINE, Embase, and Web of Science from database inception through July 2026. Eligible studies included adults or adult-separable subgroups undergoing expanded EEAs for intradural skull base tumors. The primary outcomes were CSF leak, meningitis or intracranial infection, new neurological deficit or vascular injury/stroke, hydrocephalus, mortality, and postoperative seizures. Pathology-specific adult intradural series with exact counts were quantitatively synthesized when appropriate, and large mixed EEA cohorts were summarized separately when the eligible subgroup was not separable. Results: After full-text eligibility assessment, 48 reports were retained in the extraction-status set. Three strictly adult-only exact-count reports contributed to the primary CSF leak meta-analysis, yielding a random-effects incidence of 23.0% (95% CI, 10.5–43.1%; I² = 78.7%). A sensitivity analysis adding one mixed-age cohort yielded 23.8% (95% CI, 14.5–36.6%; I² = 68.9%), while a broader sensitivity analysis including both mixed-age reports yielded 21.1% (95% CI, 12.2–33.8%; I² = 69.4%). Meningitis was reported in 6/166 patients across four studies (3.6%; 95% exact CI, 1.3–7.7%), and new neurological deficit/vascular injury/stroke was reported in 4/166 patients across four studies (2.4%; 95% exact CI, 0.7–6.1%). Postoperative seizures were reported in 4/652 patients across two studies (0.6%; 95% exact CI, 0.2–1.6%). Large mixed EEA cohorts were summarized separately because adult intradural tumor subsets could not be separated. Conclusions: CSF leak was the most consistently reported complication after expanded EEAs for adult intradural skull base tumors. The strict adult-only random-effects estimate was 23.0%, but it was based on only three studies and showed substantial heterogeneity, limiting its generalizability. Meningitis, neurological/vascular events, and seizures were uncommon in the extractable data and were summarized descriptively rather than being meta-analyzed. Large mixed EEA cohorts provide important safety context but cannot substitute for standardized adult intradural, pathology-specific reporting.

Background/Objectives: Expanded endoscopic endonasal approaches (EEA) provide direct ventral access to adult intradural skull base tumors; however, postoperative complications are variably defined and reported in the literature. This review aimed to synthesize the overall spectrum of adult intradural EEA complications and distinguish pathology-specific evidence from large mixed EEA complication cohorts. Methods: A PRISMA 2020 systematic review and meta-analysis searched PubMed/MEDLINE, Embase, and Web of Science from database inception through July 2026. Eligible studies included adults or adult-separable subgroups undergoing expanded EEA for intradural skull base tumors. The primary outcomes were CSF leak, meningitis or intracranial infection, new neurological deficit or vascular injury/stroke, hydrocephalus, mortality, and postoperative seizures. Pathology-specific adult intradural series with exact counts were quantitatively synthesized when appropriate, and large mixed EEA cohorts were summarized separately when the eligible subgroup was not separable. Results: The full-text screening set included 48 reports. Five exact-count reports, including one mixed-age contextual report, contributed to the CSF leak meta-analysis and yielded a random-effects incidence of 21.1% (95% CI, 12.2%-33.8%; I² = 69.4%). Excluding the mixed-age reports yielded 23.8% (95% CI, 14.5%-36.6%). Meningitis was reported in 6/166 patients (3.6%; 95% exact CI, 1.3%-7.7%), and new neurological deficit/vascular injury/stroke in 4/166 (2.4%; 95% exact CI, 0.7%-6.1%); these rare outcomes were summarized descriptively without continuity correction. Postoperative seizures were reported in 4/652 patients (0.6%) in two studies. Large mixed EEA cohorts have reported CSF leak rates of 1.6%-15.9% but these were not pooled because adult intradural tumor subsets were not separable. Conclusion: CSF leak was the most consistently reported complication after expanded EEA for adult intradural skull base tumors; however, its incidence varied substantially across pathologies and centers. Meningitis, neurological/vascular events, and seizures were uncommon in the extractable data and were better interpreted descriptively than as precise pooled rates. Large mixed EEA cohorts provide important safety context but cannot substitute standardized adult intradural, pathology-specific reporting.