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bioRxiv · 10.1101/454413

Validation of a low-cost, carbon dioxide-based cryoablation system for percutaneous tumor ablation

Abstract

Breast cancer rates are rising in low- and middle-income countries (LMICs), yet there is a lack of accessible and cost-effective treatment. As a result, the cancer burden and death rates are highest in LMICs. In an effort to meet this need, our work presents the design and feasibility of a low-cost cryoablation system using widely-available carbon dioxide as the only consumable. This system uses an 8-gauge outer-diameter needle and Joule-Thomson expansion to percutaneously necrose tissue with cryoablation. Bench top experiments characterized temperature dynamics in ultrasound gel demonstrated that isotherms greater than 2 cm were formed. Further, this system was applied to mammary tumors in an in vivo rat model and necrosis was verified by histopathology. Finally, freezing capacity under a large heat load was assessed with an in vivo porcine study, where volumes of necrosis greater than 1.5 cm in diameter confirmed by histopathology were induced in a highly perfused liver after two 7-minute freeze cycles. These results demonstrate the feasibility of a carbon-dioxide based cryoablation system for improving solid tumor treatment options in resource-constrained environments.

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BibTeXRIS

Surtees, B., Young, S., Hu, Y., Wang, G., McChesney, E., Kuroki, G., Acree, P., Thomas, S., Blair, T., Rastogi, S., Kraitchman, D. L., Weiss, C., Sukumar, S., Harvey, S. C., Durr, N. J.. 2018-10-26. Validation of a low-cost, carbon dioxide-based cryoablation system for percutaneous tumor ablation. https://doi.org/10.1101/454413

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