Adaption of 3D Models to 2D X-Ray Images: Optimization and Validation

Abstract: The abdominal aortic aneurysm is one of the most common aortic diseases. The aneurysm is a dilation of the aorta that may result in rupture. Today, most of the abdominal aortic aneurysms are repaired endovascularly. The physician places a stent graft at the location of the aneurysm to reduce the pressure on the aortic wall and prevent further growth of the aneurysm. The accuracy of the stent placement is critical, not to close the main branching arteries of the aorta, such as the renal arteries. The novel stent placement procedure is guided by intraoperative C-arm images overlayed with a segmented preoperative computed tomography (CT). However, the inserted devices may distort the anatomy and reduce the accuracy of the overlay. In this work the aorta and the iliac artery meshes are deformed accordingly, in order to have a correct overlay and minimize contrast agent usage. The implemented method, the skeleton-based as-rigid-as-possible (ARAP) mesh deformation, with an appropriate control point selection shows visually, as well as quantitatively promising results. The initial mean Euclidean distance between an ostium and the corresponding landmark of 19.81 mm (variance: 293.92 mm2) was reduced to 4.56 (variance: 7.88 mm2).