Chest wall temperature during radiofrequency ablation in a normal rabbit lung model

Area of Science:

• Medical Imaging and Interventional Radiology
• Pulmonology
• Oncology

Background:

• Radiofrequency ablation (RFA) is an emerging technique for lung tumor treatment.
• Understanding thermal spread and tissue damage during RFA is crucial for safety and efficacy.
• Previous studies have not fully characterized temperature changes and pathological effects in the pleura during lung RFA.

Purpose of the Study:

• To investigate the actual tissue temperature during lung radiofrequency ablation (RFA) in a rabbit model.
• To evaluate the pathological changes induced by thermal damage in the pleural tissue of the chest wall following lung RFA.

Main Methods:

• 14 Japanese white rabbits underwent CT-guided lung RFA with a 2-cm expandable electrode.
• RFA was performed at 30W or 15W, with temperature monitored 5mm from the electrode.
• Histological examination of the chest wall was conducted immediately post-ablation.

Main Results:

• Mean maximum tissue temperatures were similar at 30W (86.7°C) and 15W (82.1°C).
• Ablation times to reach 50°C, 60°C, and 70°C were significantly faster at 30W compared to 15W (P < 0.05).
• Histology revealed pleural sloughing and ring-shaped thermal injury at the electrode insertion site.

Conclusions:

• Lung RFA near the chest wall in rabbits elevates local tissue temperature above 80°C.
• Ablation immediately below the pleura causes thermal injury to the chest wall.
• These findings highlight the potential for thermal damage to adjacent structures during lung RFA.