A robotic surgery navigation system for hepatic microwave coagulation therapy

This paper proposed a needle insertion robotic surgery system for hepatic microwave coagulation of liver tumors. The system could compensate the influence caused by the patient´s respiratory motion. The system includes a needle insertion robot, a surgical planning subsystem, a magnetic tracking device and a stereo vision system. In order to meet the fundamental requirement of the system, inserting the needle accurately to the target, we proposed a method in this paper. First, a patient body fixation technique was used to reduce unintentional patient movement. Then, stereo vision technique was used to track the markers on the patient´s body surface. By combining the fixation and stereo vision, we can trace the exact motion of the organ, minimizing influence of respiratory and cardiac motion. Finally, accuracy experiment on 3D ultrasound phantom was carried out to evaluate the navigation system. The results indicated that the proposed method could improve system accuracy, enhancing the efficiency of intervention therapy for the hepatic tumors and reducing the patient´s pain.