308 Improvement in Cranial Nerve Neuropathies Following Treatment of Intracranial Aneurysms With Flow Diverters: Institutional Outcomes and Meta-analysis of Literature

Abstract

INTRODUCTION: Cranial nerve (CN) neuropathies are rare presenting symptoms of intracranial aneurysms. Ophthalmological outcomes for symptomatic aneurysms treated with flow diversion are not well established. METHODS: We conducted a retrospective review of our institutional database for patients with intracranial aneurysms presenting with CN neuropathies who underwent treatment with flow diversion between 2015 and 2023. Systematic review of the literature was performed using Medline, EMBASE, Cochrane, and manual citation searches. Random effects meta-analysis was used. RESULTS: Twelve out of 136 studies were included in this meta-analysis, totaling 261 patients. The results were combined with our institutional data. The pooled rate of improvement in any CN neuropathies following flow diversion was 76% (95% CI, 67%-84%, n = 272). Patients presenting with CNII deficits were less likely to improve following treatment compared to other CN neuropathies (pooled OR [pOR] 0.32, 95% CI, 0.16-0.63, n = 224). The pooled rate of clinical improvement was 53% in CNII deficits (95% CI, 42%-65%, n = 80) and 80% in other CN deficits (95% CI, 71%-88%, n = 106). Intervention within one month of presentation was associated with improvement (pOR 6.53, 95% CI, 1.34-31.81, n = 33). Adjunctive coiling did not demonstrate effect on the improvement rate (pOR 0.38, 95% CI, 0.07-2.13, n = 31). Near total occlusion (Raymond Roy Occlusion Classification of 1 or 2, or O'Kelly-Marotta scale of C or D) was associated with symptomatic improvement (pOR 5.29, 95% CI, 1.66-16.90, n = 118), but not total occlusion (pOR 2.83, 95% CI, 0.97-8.23, n = 118). CONCLUSIONS: Flow diversion improves CN outcomes in patients with symptomatic intracranial aneurysms. These results support the theory that CN neuropathies depend more on the pulsatility of the aneurysm sac rather than mass effect. The inferior rate of improvement in CNII deficits compared to other CN symptoms may imply an additional, more irreversible mechanism contributing to CNII visual deficits.