Advanced Ultrasound in Diagnosis and Therapy ›› 2021, Vol. 5 ›› Issue (1): 39-46.doi: 10.37015/AUDT.2021.200014

• Original Research • Previous Articles     Next Articles

A New-Designed Microwave Ablation System: Testing in ex vivo and in vivo Liver Model

Danni He, MSa, Qiao Ji, MDa, Huitong Lin, MDa, Xuankun Liang, MMa, Lujing Li, MMa, Fengping Liang, MMa, Xianxiang Wang, MMa, Kun Yuan, MSa, Zuofeng Xu, MDa,*()   

  1. aDepartment of Medical Ultrasonics, Institute for Diagnostic and Interventional Ultrasound, the Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen, Guangdong, China
  • Received:2020-03-13 Revised:2020-05-10 Online:2021-03-30 Published:2021-03-25
  • Contact: Zuofeng Xu, MD,


Objective: The present study aimed to determine the efficacy and safety of a newly designed microwave ablation (MWA) system in ex vivo and in vivo liver model.
Methods: A new MWA system (HRMW-01, Hengrui Medical, Guangzhou, China) was tested on porcine liver ex vivo with different parameter settings (50-70 W for 5-20 min). Ablation volums were measured on the gross specimens. In an in vivo study, MWA was performed at 60 W for 5 min in canine liver. Ablation volumes were identified and measured using contrast-enhanced ultrasound (CEUS) 1 w after the ablation. All animals underwent routine hematological, biochemical, and coagulation tests before ablation at 1 d and 1 w after ablation. For comparison, radiofrequency ablation (RFA) was performed using a Cool-tip system (Valleylab, Boulder, CO, USA) with an automated power setting for 12 min in both ex vivo and in vivo studies.
Results: In ex vivo studies, the mean volumes of MWA coagulation ranged from 27.8 ± 7.3 cm3 to 144.6 ± 35.9 cm 3 and increased with ablation duration and power output. MWA was prone to creating larger volume but less spherical ablation shape than RFA (P < 0.05). In in vivo studies, MWA created larger ablation volumes with shorter ablation time compared to RFA (P < 0.05). Laboratory data showed significantly higher alanine aminotransferase and aspartate aminotransferase levels 1 d after ablation than based line levels (P < 0.05) while the levels decreased close to pre-ablation levels 1 w after ablation (P > 0.05).
Conclusion: The newly designed MWA system is safe and more efficient than a commonly used RFA system. However, further clinical studies are warranted.

Key words: Microwave ablation; Radiofrequency ablation; Liver; Contrast-enhanced ultrasound; Animal study