A Novel Method for Optimal Woven EndoBridge Device Sizing by Inscribing a Rectangle in Aneurysm Projections on 2-Dimensional Angiograms

The Woven EndoBridge device is used for endovascular treatment of wide-neck bifurcation cerebral aneurysms. Conventional sizing methods often result in oversizing and require subsequent resizing. Although recent studies demonstrated the accuracy of volumetric methods for sizing, they are often complex. We aimed to develop a simplified method for estimating the appropriate Woven EndoBridge size using two-dimensional angiographic images by inscribing rectangles in aneurysms modeled as ellipsoids, which we named the Inscribed Rectangle Method. This retrospective, single-center study included 12 patients with wide-neck bifurcation cerebral aneurysms treated with the Woven EndoBridge device between May 2023 and July 2024. Aneurysm projections were approximated as ellipses, with the horizontal and vertical axes corresponding to the aneurysm's mean width and minimum height, respectively. The largest inscribed rectangle dimensions (D_rec, H_rec) were calculated. We then developed a predictive formula for Woven EndoBridge sizing based on D_rec and H_rec and compared its performance with conventional sizing methods. Adequate perioperative occlusion was achieved in 83% of cases, and no significant procedural complications were observed. Analysis of these cases revealed that the implanted Woven EndoBridge width and height were approximately D_rec × 1.5 and H_rec, respectively. The Inscribed Rectangle Method, which uses D_rec × 1.5 and H_rec, more closely predicted the implanted Woven EndoBridge size than conventional methods (p < 0.01). The Inscribed Rectangle Method provides a simplified, two-dimensional angiography-based approach for Woven EndoBridge sizing that may reduce the need for device resizing while preserving procedural efficiency.