A framework for integrating real-time MRI with robot control: application to simulated transapical cardiac interventions.

The advent of intraoperative real-time image guidance has led to the emergence of new surgical interventional paradigms including image-guided robot assistance. Most often the use of an intraoperative imaging modality is limited to visual perception of the area of procedure. In this study, we propose a framework for performing robot-assisted interventions with real-time magnetic resonance imaging (rtMRI) guidance. The described computational core of this framework, processes on-the-fly rtMRI, integrates the processed information with robot control and renders it on the human-machine interfaces. This information is rendered on a visualization and force-feedback interface for enhanced perception of a dynamic area of procedure and for assisting the operator in the safe and accurate maneuvering of a robotic manipulator. The framework was experimentally tested by applying it to a simulated Transapical aortic valve implantation with a virtual robotic manipulator. rtMRI data were processed on-the-fly in a rolling-window scheme and together with a multithreaded and multihardware implementation, the core delivered appropriate speed of 20 Hz for visualization and 1000 Hz for force feedback. The experimental results demonstrate significant improvement in the simulated task by both decreasing the duration of the procedure by half and increasing safety in the presence of cardiac and breathing motion by reducing the duration or incidents the operator collides with the tissue.