Microwave ablation of the liver abutting the stomach: Insulating effect of a chitosan-based thermosensitive hydrogel. (March 2014)

• Record Type: Journal Article
• Authors: Zhang, Dedong; Xie, Daolin; Wei, Xiaoli; Zhang, Dakun; Chen, Min; Yu, Xiaoling; Liang, Ping
• Is Part Of: International journal of hyperthermia. Volume 30:Number 2(2014)
• Page Start: 126
• Page End: 133
• Publication Date: 2014-03
• Subjects: Thermotherapy -- Periodicals; 615.832
• DOI: 10.3109/02656736.2013.874048
• Languages: English
• ISSNs: 0265-6736

Abstract

<abstract> <title>Abstract</title> <p> <italic>Purpose</italic>: Collateral thermal injury can occur as a serious complication of microwave ablation. This study aimed to assess the insulating effect of a thermosensitive, chitosan-based hydrogel during the percutaneous microwave ablation of liver tissue abutting the stomach. <italic>Materials and methods</italic>: Thermometry needles (R1–R4) were positioned at 5-mm intervals from a thermal source to measure <italic>in vitro</italic> the temperature differences due to the hydrogel (R1 closest to the thermal source). Subsequently, two groups of eight rabbits each were injected with 10 mL of hydrogel solution or 410 ± 95 mL of 5% saline between the liver and stomach wall. A control group of eight rabbits received no ablation protection measures. The livers were ablated with 40 W for 300 s in 24 ablation zones. The severity of thermal injury to the stomach wall was assessed histologically. <italic>Results</italic>: <italic>In vitro</italic>, the mean maximum temperature difference between the R1 and R2 thermometry needles was 31.3° ± 0.1 °C. When R1 was over 60 °C, the mean temperatures at R2, R3, and R4 were 29.8° ± 0.1 °C, 18.6 ± 0.3 °C, and 18.1° ± 0.1 °C, respectively. After ablation for 300 s, the maximum temperature at R2 was 48.7° ± 0.2 °C. None of the rabbits injected with gel showed any injury after ablation; however, the other two groups showed varying degrees of thermal injury. <italic>Conclusion</italic>: The <italic>in situ</italic> gel protected the adjacent stomach wall from injury during percutaneous microwave ablation of liver tissue. Although the present technique appears promising, further studies are necessary prior to clinical application.</p> </abstract>