Transapical aortic valve replacement under MRI guidance in a beating heart is a recent minimally invasive technique that could benefit from a surgical assistant system. We present a robotic surgical assistant system that can precisely and repeatably deliver aortic valve prostheses. The surgical system consists of an imaging system, an Innomotion robotic arm, a 3-DoF valve delivery module and user interfaces. Interactive control allows the physician to remain in the loop and adjust the orientation and position using real-time MR feedback. The 3-DoF valve delivery module is developed to deploy both balloon-expandable and self-expanding stented prostheses. We use a new compact fiducial that can be placed close to the volume of interest and requires a single image plane for image based robot registration. We evaluate the MRI compatible valve delivery module for both types of prostheses. The accuracy for prosthesis delivery is about 0.8 mm and 1.5 mm, for self-expanding and balloon-expandable prostheses, respectively. Preliminary results in ex-vivo experimentation suggest that the robotic system can be translated into animal and clinical models.

MRI compatible robots are emerging as useful tools for image guided interventions. A shared control between a user and the MRI compatible robot makes it more intuitive instrument especially during setup phases of interventions. We present a MRI compatible, hands-on cooperative system using Innomotion robotic arm. An economic MRI compatible user input sensor was developed and its functionality was tested under typical application conditions. Performance improvement in phantom tasks shows promise of adding hands-on interface in MRI compatible robots.