Virtual Fixtures for Robotic Cardiac Surgery

We are developing virtual fixtures for the internal mammary artery (IMA) harvest portion of robot-assisted coronary artery bypass graft procedures. A preoperative CT scan will be processed to define the location of the IMA. In surgery, the patient's anatomy will be registered to the image data, then a virtual fixture will constrain the instrument's motions, as commanded by the surgeon, to appropriate paths adjacent to the artery. As a preliminary test, a virtual wall is implemented on a commercial surgical robot system. Results from a dissection task show that execution is faster and more precise than with conventional freehand techniques.