A preoperative ultrasound planning of robotic system for hepatic microwave coagulation

This paper proposed a needle insertion robotic system for ultrasound guided hepatic microwave coagulation. The system includes a needle insertion robot, a pose tracking device and a surgical planning subsystem composed of pre-operative module and intra-operative module. One unique contribution of the system is real-time prediction of the microwave thermal field distribution generated by the needle´s electrode in the liver. The specific absorption rate of microwave energy can be calculated and corresponding temperature field can be visualized in the 3D surgery scene generated by the surgical planning system. Such information can be used to help the surgeon adjust the operation to improve the treatment effect. Experiments for the system accuracy test demonstrate that the mean value of the error is less than 2 mm. The temperature field distribution is verified by a 5.6% difference between real and predicted coagulation volume. These facts indicate that the proposed technique is promising to improve the effect of the interventional radiology therapy.