Abstract
In this seminar, I discuss three types of applied research in which collaborations between biomedical engineers and medical doctors can advance the surgical field of vascular grafting. First, I describe a mock circulatory system designed to simulate regional hemodynamics and input impedance in the human aorta. This circuit can estimate the cardiac work that results from implanting or replacing a synthetic aortic graft. Simulation shows that replacement of an aortic graft made of silicone rubber with one made of polytetrafluoroethylene (PTFE) increases cardiac work significantly. Second, I show how technology originally developed for neurosurgical navigation can be applied to the replacement of a thoraco-abdominal aortic aneurysm with a PTFE graft. Here, a registration method combines visual relationships between the real operative space and a three-dimensional space constructed from images obtained by computed tomography. The system employs a phantom thoraco-abdominal artery to accurately locate the Adamkiewicz artery that often, but not always, arises from a left inferior intercostal artery. To date, this navigation system has contributed to the surgical success of eighty-six aortic grafts. Third, I introduce a computational fluid dynamic (CFD) program to predict the distribution of blood flow in a three-branch graft during thoracic endovascular aortic repair (TEVAR). Phase-contrast magnetic resonance angiography image (PC-MRI) of the blood flow distribution determines the initial conditions in patients and healthy individuals. Calculations show a permissible 3% decrease in flow in the descending aorta after surgical endovascular debranching. Finally, I emphasize the importance of educating and training new leaders of Medical Regulatory Science to achieve a true engineering-medical collaboration at Tokyo Women’s and Waseda University Joint Institution for Advances Biomedical Sciences.
