Determining Epicardial Surface Motion Using Elastic Registration: Towards Virtual Reality Guidance of Minimally Invasive Cardiac Interventions

Minimally invasive cardiac surgery is performed on the beating heart, through inter-costal ports. The two major limitations of these procedures are: selecting port locations for optimal target coverage (based on chest x-rays and angiograms), and navigating surgical tools through a dynamic and confined environment using a 2D endoscope. To supplement the current surgery planning and guidance strategies, we continue developing VCSP – a virtual reality, patient-specific, thoracic cavity model derived from 3D pre-procedural images. In this work, we apply elastic image registration to 4D images of the heart to model the epicardial surface over the cardiac cycle. We validated our registration algorithm on CT images of a dynamic cardiac phantom and of normal canine hearts, and found the error to be 1.14 ± 0.31 mm and 0.61 ± 0.12 mm, respectively. We believe this method of modeling the epicardial surface is sufficiently accurate to be applied in cardiac surgery planning and guidance.