Radiologically measured optic nerve sheath diameter as a predictor of mortality and functional outcomes in stroke patients: A systematic review and meta-analysis

Abstract

ABSTRACT Objective: Optic nerve sheath diameter (ONSD) has emerged as a non-invasive marker of intracranial pressure and may provide prognostic information in patients with acute stroke. However, studies evaluating its association with mortality and functional outcomes have reported inconsistent findings. This systematic review and meta-analysis aimed to evaluate the prognostic value of radiologically measured ONSD in stroke patients. Methodology: A systematic search of PubMed, Embase, Scopus, and Web of Science was conducted from database inception to March 10, 2026. Observational studies evaluating ONSD measured by computed tomography or ocular ultrasonography in adult stroke patients were included. Random-effects meta-analysis was performed to pool mean differences (MD) in ONSD between outcome groups and odds ratios (OR) for mortality associated with elevated ONSD. Results: Sixteen studies were included in the review. Seven studies reported ONSD values for mortality analysis, demonstrating significantly larger ONSD in patients who died compared with survivors (MD 0.50 mm, 95% CI 0.15-0.85; I²=86%). Five studies evaluating functional outcomes showed significantly greater ONSD in patients with poor outcomes (MD 0.60 mm, 95% CI 0.26-0.93; I²≈89%). Three studies reporting risk estimates indicated that elevated ONSD was associated with a higher risk of mortality (OR 5.87, 95% CI 3.11-11.09; I²=64%). Sensitivity analyses and subgroup analyses confirmed the robustness of these findings. Conclusions: Enlarged ONSD may be associated with increased mortality and poorer functional outcomes in stroke patients. ONSD measurement may serve as a simple, non-invasive adjunct for early prognostic assessment, although further standardised prospective studies are needed. Registration No: PROSPERO (CRD420261344376).