Virtual angioscopy and 3-dimensional navigation findings of the aortic arch after vascular surgery.

The anatomy of the aortic arch is variable, and its detailed analysis on computed tomography (CT) scan may be difficult. Indeed, its curvature, angulations, length of horizontal portion, and origin of supra-aortic trunks (SAT) may vary among individuals. Furthermore, drastic modifications of the patient’s anatomy may be observed after open or endovascular surgery and in case of congenital abnormalities. The 3-dimensional (3D) nature of the aortic arch is then difficult to assess on an axial plane. Current workstations have permitted the reconstruction in 2 dimensions of the aortic arch, and the volume-rendering technique or shaded surface display gives an external analysis of the structures. Virtual angioscopy, first described in 2001,1 allows the realization of an endoluminal navigation in 3 dimensions. It is based on the notion of active vision, in which only visual perception drives the motion of the virtual angioscope.2 The navigation mode allows manual analysis of the elements of the aortic arch under different viewing angles and dynamic localization of abnormalities in relation to SAT with high precision and better understanding. Here are examples of patients having undergone an aortic arch procedure and for whom the fly-through with the help of virtual angioscopy has permitted better understanding of abnormalities of the aortic arch.