Virtual simulation accurately predicts in vivo flow diverter length for intracranial aneurysm treatment: a multicenter validation study

BACKGROUND: Accurate device sizing is crucial for successful flow diverter (FD) therapy in intracranial aneurysms. This study assesses the accuracy and clinical utility of the Ankyras virtual simulation software (Mentice AB, Gothenburg, Sweden) in predicting FD length across multiple device types and manufacturers. METHODS: We retrospectively analyzed 193 FDs (7 device types) deployed in 180 patients with 230 intracranial aneurysms. Simulation-based prediction of effective lengths (simulated length (SL)) and nominal manufacturer specifications (labeled length) were compared with measured in vivo lengths (measured length (ML)). Performance was evaluated using simulation accuracy (SA), absolute error (AE), relative error (RE), length ratio, and correlation analysis. RESULTS: Virtual simulation demonstrated good clinical usability, achieving a mean absolute deviation of only -1.38 mm at the proximal landing zone compared with ML. Simulation-based predictions showed significantly superior accuracy compared with nominal manufacturer specifications (SA 89.6±11.3% vs 81.8±13.7%, P