A Needle Guidance System for Hepatic Tumor Ablation That Fuses Real-Time Ultrasou

DESCRIPTION (provided by applicant): This project proposes to enhance the capabilities of InnerOptic's InVision System (IVS) for needle guidance during hepatic tumor ablation procedures via an innovative and inexpensive method to warp pre-operative CT data in real time. Ablation has been demonstrated as a promising alternative to surgical resection to treat hepatic tumors, but needle placement difficulties have been reported due to poor visualization of the anatomy with currently-available technology. Conventional ultrasound guidance is intra-operative, but some tumors are only visible in computed tomography (CT); however, CT data of soft tissue becomes obsolete as soon as the tissue moves even a small amount (e.g., from breathing). We have already developed the IVS technology to address this problem: with it, the positions and orientations of the ablation needle and of the intra-operative ultrasound transducer used for needle guidance are continually monitored. A stereoscopic computer-generated real-time visualization displays dynamic avatars of needle and transducer as the physician advances the needle towards the target; in this way, the spatial relationship between needle and ultrasound slice is clear, and the surgeon can more easily target a feature in the ultrasound slice with the ablation needle. Here, we propose an improvement to this guidance system that will enhance a physician's spatial understanding even further. We introduce a novel and computationally-inexpensive means to warp pre-operative computed tomography (CT) data, and an updated guidance system that incorporates the real-time-deformed CT data in registration with the intra-operative ultrasound. The physician would then benefit from the complementary information provided by both the ultrasound and CT data, and could optimally plan and execute the ablation procedure. In this Phase I, we propose to develop the prototype by enhancing our existing IVS, and thus leveraging hardware and software that is already available to us. We will then verify the performance accuracy of the system, and proceed with both quantitative and qualitative testing by our surgeon consultants. We will pursue two rounds of testing: the first will provide an opportunity to optimize the ergonomic aspects of the device, and the second will yield both quantitative and qualitative performance data. The technology described here is by no means limited to ablation procedures. In the future, it could in the future be adapted to any procedure in which needles, ultrasound and pre-operative scans such as CT or MRI are employed. PUBLIC HEALTH RELEVANCE: We propose an advanced visualization system for ablation of hepatic tumors, which is a surgical procedure in which a needle-like device is inserted into the center of a cancerous lesion and is energized in a way so as to burn and effectively remove the timorous tissue. A promising alternative to surgical resection, this approach has several advantages over traditional resection, including reduced trauma and recovery time for the patient, but it requires significant skill with ultrasonography for guidance in the careful placement of the probe that is required for maximization of tumor destruction, and minimization of healthy tissue destruction. The system proposed here will allow even a novice surgeon to place the probe accurately and quickly, and can enable an expert surgeon to perform the procedure more quickly.