Computerized Model Helps Perform Robotic Surgery on the Beating Heart

A computerized three-dimensional (3D) model tracks the motion of the heart's surface as it beats, assisting surgeons in using robotics to operate on the beating heart.

Developed by researchers at the Montpellier Laboratory of Informatics, Robotics, and Microelectronics (LIRMM; France), the new approach relies on a method for active cancellation of cardiac motion, by combining an efficient algorithm for 3D tracking of the heart surface based on a thin-plate spline (TPS) deformable model, and an illumination compensation algorithm able to cope with arbitrary illumination changes when using stereo images from a calibrated stereo endoscope. The resulting 3D mathematical representation of the heart's surface as it moves during pumping allows a robotic arm to continually adjust to heart and chest movements during the surgery, thus virtually eliminating the hearts' motion--from the surgeon's point of view--during the operation. The proposed tracking method has been evaluated offline, on in vivo images acquired by the Intuitive Surgical (Sunnyvale, CA, USA) daVinci surgical robotic platform. The study was published on December 11, 2009, in the International Journal of Robotics Research.

"In beating heart surgery, cardiac and respiratory motions are important sources of disturbance, hindering the surgeon's gestures and limiting the types of procedures that can be performed in a minimally invasive fashion,” explained study authors Rogério Richa, M.D., Philippe Poignet, M.E., Ph.D., and Chao Liu, Ph.D. "In this context, computer vision techniques can be used for retrieving the heart motion for active motion stabilization, which improves the precision and repeatability of the surgical gestures.”

Over the last 10 years, robotic arms have become essential in many surgical procedures, including microsurgery and procedures such as heart surgery, coronary bypasses, and many kinds of brain surgery that require extremely delicate movements. Researchers have made many attempts to use computer modeling to account for heart and breathing motion; however, previous efforts have relied on two-dimensional (2D) imaging combined with additional stages, negating instantaneous feedback during an operation. The new 3D imaging predicts the heart movements in a single step, making it faster in actual surgical environments.

Related Links:
Montpellier Laboratory of Informatics, Robotics, and Microelectronics
Intuitive Surgical