Robotically Controlled Catheter-Based Imaging for Beating Heart Surgery
A robotic system for automatic ultrasound imaging during beating heart surgery can increase situational awareness, improve workflow, reduce procedure times, and reduce complications. This system steers an ultrasound imager in the tip of a steerable catheter to automatically image cardiac structures or working instruments (such as ablation catheters) inside the heart. Steering is controlled by using a closed-form solution for forward and inverse kinematics that calculates the direction of the side-facing ultrasound imaging plane. Our system is capable of accurate position control, angular adjustments, and instrument tracking.
Commercially available ultrasound imaging catheters, known as intracardiac echocardiography (ICE), have an ultrasound transducer in the tip for acquiring high-resolution images from within the heart during procedures. This is useful for reliable imaging in diagnosis, navigation, and treatment. ICE catheters, which are currently controlled manually, are extremely challenging to aim due to the complex relationship between handle knobs and imager motion. The difficulty in steering ICE has limited its use to a few critical tasks.
Researchers: Alperen Degirmenci, Laura Brattain, and Paul Loschak
Robotic Catheters for Beating Heart Surgery
The goal of this project is to develop 3D ultrasound-guided robotic catheters for beating heart surgery. Cardiac surgery is currently an invasive procedure that often involves stopping the heart and opening the chest. The robotic catheter system removes these potential risks by allowing a robotic tool to operate on the beating heart by compensating for the fast motions using 3D ultrasound guidance. The motion compensation allows the surgeon to control the catheter to accurately repair and modify the moving structures inside the heart while it is still beating. The system uses 3D ultrasound guidance and visual servoing to control the catheter tip inside the beating heart.
The focus of this project has been the design and control of the motion-compensating robotics catheters. See the papers below for more information on the catheter system designs, including actuation, catheter components, force sensors, and end effectors. In order to accurately control the catheter tip position and applied forces, custom control methods were developed that compensate for the catheter performance limitations of friction and backlash. See the papers below for more information on these topics.
Researchers: Samuel B. Kesner
3D Ultrasound-Guided Robotic Motion Compensation for Beating Heart Intracardiac Surgery
Traditionally, surgeons have coped with heart motion during cardiac surgery by stopping the heart and using the heart-lung machine to pump and oxygenate the blood. There is great interest in avoiding the heart-lung machine because of its serious side effects. Furthermore, the outcome of a surgery on a stationary heart is challenging to predict. Beating-heart surgery prevents the morbidities associated with the heart-lung machine and potentially improves surgical outcomes by allowing the surgeon to evaluate repair, particularly of valves, during the operation. However, this type of procedure is difficult for surgeons to perform because of the heart’s motion.
In previous work, we demonstrated that real-time 3D ultrasound is an effective imaging technology for guiding surgeries inside the heart. In this project, we have developed a 3D ultrasound-guided motion compensation system that tracks heart motion and allows the surgeon to operate on the fast-moving structures of the beating heart without risk of damaging them. We focus on the beating heart repair of the mitral valve through mitral annuloplasty. The design of the system is guided by the clinical observation that the rapid motion of the mitral annulus is dominated by translation along a single axis between the left atrium and left ventricle. This allows the use of a simplified 1 DOF motion compensation system that can be used for surgical procedures like the anchor driving found in mitral annuloplasty.
Researchers: Shelten Yuen, Samuel B. Kesner, Daniel Kettler, Richard Plowed, and Paul Novotny