Woven EndoBridge device apposition and compression using Sim&Size virtual simulation correlate with aneurysm occlusion status: a retrospective cohort study

Background Virtual simulation is increasingly used for aneurysm treatment. This study aimed to explore whether mechanical behavior biomarkers of the Woven EndoBridge (WEB) device as computed by Sim&Size simulation software were associated with aneurysmal occlusion status at follow-up. Methods Consecutive patients with aneurysms treated with WEB were retrospectively enrolled (January 2014 to December 2021). Aneurysms were included if three-dimensional digital subtraction angiography and follow-up imaging were available. Device apposition and compression within the aneurysm sac were retrospectively calculated by Sim&Size simulation software. Mean global and maximum compression, mid-device and neck compression, and the Spruce index of heterogeneity of deformation of the simulated device were calculated. A multivariate Lasso regression was performed. Results A total of 81 aneurysms in 80 patients (56 females; mean age 60±12 years) were analyzed. At a mean radiological follow-up of 3±2 years, 62 (77%) showed an adequate occlusion. Mean apposition in the inadequate and adequate occlusion group was 42.9±11% and 53.97±12%, respectively (P=0.002), mean global compression was 4.95±3% and 7.85±6% (P=0.035), respectively, and maximal compression was 13.44±6% and 20.73±11%, respectively (P=0.009). Compressions at mid-level and neck level were comparable between the two groups. The Spruce index was higher in the inadequate occlusion group (0.16±0.05 vs 0.20±0.05, P=0.005). Multivariate analysis showed that wall apposition, maximum compression and the Spruce index were independent prognosticators of aneurysm occlusion. Conclusions Wall apposition, maximum compression and the Spruce index computed by Sim&Size software predicted the likelihood of aneurysm occlusion at follow-up, after WEB treatment.