Intra-operative "pick-up" ultrasound for robot assisted surgery with vessel extraction and registration: A feasibility study

Abstract

We propose the use of a "pick-up" ultrasound transducer for robot-assisted minimally invasive surgeries. Unlike prior approaches, the ultrasound transducer is inserted before the procedure and remains in the abdominal cavity throughout. We present a new design for such an intra-abdominal ultrasound transducer with a handle that can be grasped in a repeatable manner using a da Vinci Pro-Grasp tool. The main application is mapping the vasculature, which is segmented from Doppler and B-mode images using a Kalman-filtering approach. Our goal is employ the vasculature to register pre-operative CT to intra-operative camera images. To demonstrate the feasibility of the approach, we use an ultrasound flow phantom to register a CT surface model to extracted ultrasound vessel center points using an iterative closest point method. The transducer was tracked with electromagnetic sensors and a target registration error of 3.2 mm was calculated. The initial application will be nephrectomy where vessel localization is paramount. © 2011 Springer-Verlag.