Electromagnetic navigation system combined with High-Frequency-Jet-Ventilation for CT-guided hepatic ablation of small US-Undetectable and difficult to access lesions

Objective
To report the feasibility and efficacy of percutaneous ablation of small hepatic malignant tumors that are invisible on ultrasound and inaccessible using in-plane CT guidance, using a combination of high-frequency jet-ventilation (HFJV) and electromagnetic (EM) needle tracking.

Outcomes
Twenty-one patients with 27 treated lesions (14 hepatocellular carcinomas and 13 metastases) were included in this study. Mean tumor size was 12 ± 5.7 mm. Thirty-three percent of the lesions were located on the hepatic dome. Complete ablation was obtained in 100% at the 3- and 6-month MRI follow-up. The ablation probe was correctly placed on the first pass in 96%, with a mean path-to-tumor angle of 7 ± 4 degrees and a mean tip-to-tumor distance of 22 ± 19mm. A readjustment for additional overlapping application resulted in complete treatment in 4 patients. Needle placement took a mean 23 ± 12 min with mean radiation doses of 558 mGy*cm. No major complications were reported.

Conclusion 
Percutaneous liver ablation of lesions that cannot be seen on US and requiring out-of-plane CT access can be successfully and safely treated using electromagnetic-based navigation and jet-ventilation.

Reference
Electromagnetic navigation system combined with High-Frequency-Jet-Ventilation for CT-guided hepatic ablation of small US-Undetectable and difficult to access lesions S. Volpi, G. Tsoumakidou, A. Loriaud, A. Hocquelet, R. Duran, A. Denys

International Journal of Hyperthermia, October 17, 2019