Quantitative and intuitive liver tumor treatment with multi-constrained planning and holographic augmented reality

Abstract

In recent years, thermal ablation has become a widely accepted minimal invasive treatment for liver tumor patients. However, surgical planning and performing are still challenging tasks in two aspects: on one hand, surgical planning relies on fulfilling multiple medical constraints, especially for the ablation based on configurations of multiple electrodes. On the other hand, the precise and efficient performance of the percutaneous tumor punctures under free-breathing conditions is hard to achieve because of the high dependency on surgeons' experience. <br /> This thesis presents a novel quantitative and intuitive surgical planning and navigation modality for percutaneous respiratory tumor puncture via holographic visualization, which overlays the pre-operative computer-assisted surgical planning and navigation information precisely onto the intra-operative surgical scenario. <br /> In the pre-operation stage, we present the versatile approach for the computer-assisted planning of liver tumor thermal ablation, including the multi-electrode configuration for large tumors based on the patient-specific anatomical data and the insertion trajectory determine based on a series of medical constraints. We also build up the internal-external correlation model which represents the liver and tumor state under free-breathing with respect to the skin markers attached to the patient. In the intra-operative stage, we first propose a virtual-real alignment method to precisely superimpose the virtual information on the surgical scenario. Then, a user-friendly collaborative holographic interface is designed for real-time 3D respiratory tumor puncture navigation, which can assist surgeons in fast and accurately localizing needles towards the target step-by-step. <br /> In comparison to the state-of-the-art method and manually sketched thermal planning result, our method can achieve compact ablation regions without relying on assumptions of potential needle path search. This navigation system is validated on the static abdominal phantom, in-vivo beagle dogs, or pigs with artificial lesions. Experimental results demonstrate that the proposed holographic augmented reality navigation modality can effectively reduce the needle adjustment for precise puncture. <br /> Our surgical navigation system shows its clinical feasibility to provide the quantitative planning of optimal thermal ablation, which allows completely ablating the tumor region as well as reducing the damage of healthy tissue in comparison to the previous state-of-the-art method. In addition, the proposed augmented virtual reality navigation system can effectively improve the precision and reliability in percutaneous hepatic tumor treatment and has the potential to be used for other surgical planning and navigation tasks.