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Percutaneous ablation is becoming a viable treatment option for patients with early-stage hepatocellular carcinoma (HCC) who are not candidates for surgical resection or liver transplantation.1 The success of the treatment is measured by the complete coverage, plus a positive margin, of the tumor being contained within the ablation lesion.2 In this project, a multi-modality anthropomorphic phantom with simulated tumor and vascular flow was developed. The phantom consists of five different parts: the left and right lobes, internal and external vasculature (part of the Inferior Vena Cava), and the tumors. The geometry of these anatomical features are based on patient-specific CT data. Our anthropomorphic liver phantom is made with PolyVinyl Alcohol cryogel (PVA-c) to serve as an Ultrasound-, MRI-, and CT-compatible tissue-mimicking material. Talcum powder was added to the PVA-c to provide realistic speckle under ultrasound (US) imaging, with the optimal concentration being determined by experiment. The Talcum concentration of the tumors was evaluated by US and CT imaging. To create the closed-loop vasculature flow, positive silicone vasculature molds were inserted into the liver body mold prior PVA-c filling. After the freeze-thaw cycles, the silicone vasculature molds are extracted from the liver body creating a network of canals. To recreate the blood flow, a water pump was connected to the liver phantom vasculature to allow the flowing through the internal canals. Differentiation between the liver tissue, vessels, and simulated tumors was clearly visualized in US and CT imaging. Color Doppler was acquired to test the flow of the closed-loop vasculature. The antropomorphic characteristics and the manufacturing technique makes our liver phantom customizable to work as a sandbox environment for needle puncture procedures (i.e. focal ablation) as well as training and validation of surgical navigation systems for these interventions.
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