Towards a medical virtual reality environment for minimally invasive cardiac surgery

We have developed a visualization environment to assist surgeons with therapy delivery inside the beating heart, in absence of direct vision. This system employs virtual reality techniques to integrate pre-operative anatomical models, real-time intra-operative imaging, and models of magnetically-tracked surgical tools. Visualization is enhanced via 3D dynamic cardiac models constructed from high-resolution pre-operative MR or CT data and registered within the intra-operative imaging environment. In this paper, we report our experience with a feature-based registration technique to fuse the pre- and intra-operative data during an in vivo intracardiac procedure on a porcine subject. Good alignment of the pre- and intra-operative anatomy within the virtual reality environment is ensured through the registration of easily identifiable landmarks. We present our initial experience in translating this work into the operating room and employing this system to guide typical intracardiac interventions. Given its extensive capabilities in providing surgical guidance in the absence of direct vision, our virtual environment is an ideal candidate for performing off-pump intracardiac interventions.