J Korean Radiol Soc.  2008 Mar;58(3):255-260. 10.3348/jkrs.2008.58.3.255.

Percutaneous Cryoablation for the Normal Lung evaluated in Rabbits: A Radiologic-Pathologic Correlation

• Kim YJ
• Jin GY
• Han YM
• Chung GH
• Choi EJ
• Chung MJ

• KMID: 1852938
• DOI: http://doi.org/10.3348/jkrs.2008.58.3.255

Abstract

PURPOSE
To assess the CT and histological findings after cryoablation in the normal lung of rabbits.
MATERIALS AND METHODS
After performing chest CT on rabbits, we inserted a cryoneedle toward the lower lobe of the right lung. We performed percutaneous cryoablation that was composed of freeze-thaw-freeze cycles (25 minutes) for group 1 animals and one cycle of variable freezing time (10-20 minutes) for group 2 animals. We measured the longest (Dl) and shortest diameter (Ds) of the ablated zones that were determined after cryoablation for all of the CT images. After cryoablation, we performed a pathological examination.
RESULTS
The mean Dl and Ds of the ablated zone was 28.1+/-3.9 mm and 16+/-1.6 mm, respectively, for group 1 rabbits. For group 2 rabbits, the mean Dl and Ds was 28.7+/-6.3 mm and 14.4+/-3.8 mm, respectively, for one cycle of 20 minutes freezing time. Based on the histological findings, the ablated zone was composed of a necrotic, hemorrhagic, and inflammatory area, in order from the center to the outside. Although each area was well differentiated in group 1 rabbits, only freezing for one cycle of 20 minutes for the group 2 rabbits gave the same results as for the group 1 rabbits.
CONCLUSION
A total freezing time of at least 20 minutes and two more freeze-thaw-freeze cycles might be important factors for providing a sufficient area of the ablated zone and uniform necrosis during cryoablation.

Keyword

Catheter ablation; Cryotherapy; Rabbits; Lung neoplasms

MeSH Terms

Animals
Catheter Ablation
Cryosurgery
Cryotherapy
Freezing
Lung
Lung Neoplasms
Necrosis
Rabbits
Thorax