Prototype of a 3D-navigation system for interventional therapy of aortic aneurysms

Introduction: Over the last decade, interventional endovascular stenting of aortic aneurysm has been developed from single center experiences to a standard procedure in many countries. One integral part for the success of this minimally-invasive procedure is innovative and improved vascular imaging. One of the most difficulty in learning and performing this interventional therapy is the fact, that the three-dimensional vascular tree has to be overlain with the two-dimensional angiographic scene by the vascular surgeon. Methods: We report the development of real-time navigation software, which allows a three-dimensional endoluminal view of the vascular system during an EVAR-procedure in patients with infrarenal aortic aneurysm. Even in patients with complex anatomy, the surgeon or the interventionalist achieves an accurate option of spatial perception concerning the current vascular anatomy, e.g. the position of the guide-wire. We analyzed patients with an infra-renal aortic aneurysm in which the planning CT-Scans were volume-rendered. At the beginning of the intervention the relevant landmarks were matched in real-time with the two-dimensional angiographic scene. During intervention the software continuously registers the position of the guide-wire or the stent. An additional 3d-screen shows the generated endoluminal view during the whole intervention in real-time. Results: Our preliminary results of navigated endoluminal virtual angioscopy are promising. The ""Virtual angioscope"" may improve intraoperative visualization, placement of guide-wires and stents. It may reduce the amount of contrast agents and exposure to x-Rays. The prototype also offers the possibility of intervention planning and simulation which may lead to a reduced learning curve and therefore patient safety. Conclusion: Not only for pre-interventional simulation, even in training of inexperienced surgeons or interventionalists, our 3D navigation system may offer better visualization in complex endoluminal aortic procedures.