Integrated Image-Guided RF Ablation for Liver Tumors

DESCRIPTION (provided by applicant): The goal of this project is to facilitate accurate positioning of radiofrequency (RF) ablation probes during liver tumor treatment. The system developed will integrate pre-procedural CT imaging with electromagnetic device tracking. New methods of soft tissue registration and soft tissue motion compensation will be combined with a versatile RF probe tracking device and computer guidance software. This will enable interventional radiologists to accurately position and reposition RF probes. More accurate placement, positioning, and repositioning of probes responds to a clinical weakness of existing RF ablation techniques and should provide improved outcomes for this rapidly expanding and minimally invasive cancer treatment. The specific aims of the proposal are: 1. Develop an integrated system to provide accurate guidance for RF probe placement based on preprocedural CT images. The integrated system will include: a. Son tissue registration using electromagnetically tracked catheters & guidewires b. Intravascular soft tissue dynamic referencing using electromagnetically tracked catheters c. Accurate delivery ofRF energy using an electromagnetically tracked RF ablation probe 2. Characterize the system accuracy in phantom studies. The accuracy of the system will be evaluated in a liver/respiratory motion simulator. We will determine the simulated clinical accuracy with various levels of respiratory motion effects. 3. Conduct feasibility studies in four swine by inserting the registration and dynamic referencing targets into the hepatic vein via an internal jugular puncture. We will then target percutaneously implanted simulated lesions using a tracked RF ablation probe. The procedure accuracy will be evaluated by measuring the distance of the RF needle probe tip from the planned target using biplane fluoroscopic images.