Fig. 1

Centerline creation and roadmapping step-by-step tutorial. Begin by distinguishing bone, vessel and calcification densities from the pre-operative CT and start building the centerline for the vessels of interest using the reformatted views (a, white arrow on initial axial starting point). The centerline will start growing in 3D (b, white arrow). Once the occlusion is reached, start a bridge and deposit multiple points throughout the occluded vessel until the re-entry point (c-d) to continue growing the line (e). Adjust the vessel centerline using a dedicated tool (f). Repeat the operation on other vessels if necessary (g). Before proceeding with intra-procedural vessel selection, an assisting x-ray technologist fuses the pre-operative data on live fluoroscopic images using a Bi-View guided workflow all at tableside. Registration is performed by cross-referring fixed fluoroscopic landmarks (in this case, pelvic and spinal bones) with the same osseous landmarks on CT using only 2 fluoroscopic images approximately 50–60 degrees apart (in this case, RAO 15 (h) and LAO 40 (i). After initial registration, the vessel centerlines are displayed to the user (j), providing guidance to navigate the catheter compared to the standard fluoroscopy image (k). Dynamic adjustments to the registration are performed as needed by adjusting the red bony landmark overlays. Note that the occluded right common iliac vein (white arrow) and infrarenal inferior vena cava (black arrow) have already been crossed without contrast instillation using this technique