[Thermal protection of targeted air instillation in CT-guided radiofrequency ablation]

Abstract

Purpose: To evaluate targeted intraperitoneal air instillation for the protection of adjacent structures at high-risk liver metastasis sites.

Materials and methods: On the basis of an interdisciplinary indication for radiofrequency ablation (RFA), targeted air instillation (up to 200 cc) was performed in 6 patients with a total of 6 liver metastases over an anterior or right lateral access route with a 22 G Chiba needle for the distension of the structures as well as protection against thermal damage from RFA in the close relationship of liver lesions to the stomach or colon.

Results: In 6 patients (mean age approximately 66.3 years, 4 males, 2 females) with a risky location of a colorectal metastasis (liver segment III or VI), the targeted air instillation was performed between the liver and stomach (4 / 6) and colon (2 / 6). Protection against thermal damage was able to be established in 6 / 6 liver metastases prior to RFA. All tumor sites were ablated completely without the occurrence of complications requiring treatment.

Conclusion: The additional instillation of air into the peritoneum for distension and thermal protection is a useful extension of the RFA technique, which allows successful ablation at high-risk liver tumor sites and also allows interventional radiologists to treat tumor manifestations closely related to the colon or stomach.