Fluid-modulated bipolar radiofrequency ablation: an ex-vivo evaluation study

Area of Science:

• Medical Imaging and Interventional Radiology
• Biomedical Engineering
• Surgical Oncology

Background:

• Radiofrequency ablation (RFA) is a medical procedure where heat is used to destroy abnormal tissue.
• The effectiveness of RFA can be influenced by factors such as fluid injection.
• Understanding fluid modulation is key to optimizing RFA outcomes.

Purpose of the Study:

• To investigate how different injected fluids impact the efficacy of bipolar radiofrequency ablation (RFA).
• To assess the potential of various fluids in modulating RFA-induced coagulation in an ex-vivo liver model.

Main Methods:

• Utilized a bipolar RFA system with an internally cooled applicator on ex-vivo porcine liver.
• Injected 1 ml of seven distinct fluids prior to ablation.
• Measured lesion dimensions, volume, and calculated an efficiency index, comparing results to RFA alone.

Main Results:

• All tested fluids increased mean coagulation volume compared to RFA without fluid injection.
• Significant lesion enlargement was observed with gadopentetate dimeglumine, hydroxyethyl starch, glucose, and ethanol.
• Hydroxyethyl starch yielded the largest lesions, while glucose allowed for the most energy application.

Conclusions:

• Fluid injection enhances RFA by altering both electrical and thermal conductivity.
• Further in-vivo studies are necessary to validate these findings with larger injection volumes.