In vivo evaluation of bronchial injury of irreversible electroporation in a porcine lung ablation model by using laboratory, pathological, and CT findings.

ABSTRACT

Irreversible electroporation (IRE) creates permanent pores in the cell membrane, leading to irreversible cell death. In this study, the impact of IRE on bronchial injury was comprehensively examined in a timed series study. Altogether, 8 Bama miniature pigs were included in this study and were randomly assigned to experimental and control groups. The experimental group underwent IRE that was guided and monitored by spiral computed tomography (CT). The monopole probe of the IRE was positioned at the right pulmonary hilum. Specimens were collected at 0 h, 2 h, 2 d, 7 d, and 14 d after the IRE procedure for a pathological examination. A small amount of needle-tract bleeding occurred in two animals, and mild pneumothorax occurred in another. IRE can elicit acute bronchial inflammation, bleeding, and mucosal injury, but severe complications were not found. Pathological examinations and transmission electron microscopy (TEM) showed dead vascular epithelium cells in the region of the ablation, while the bronchioli and the vascular extracellular matrix were preserved. At 2 hours post-IRE, there were marked increases in bronchoalveolar macrophages (P<0.001), but the inflammation could recover after 14 days and showed no statistical significance when compared with the control group at the same time. In conclusion, CT-guided IRE ablation can elicit acute but recoverable bronchial inflammation, bleeding, and mucosal injury in porcine lung tissues. However, longer follow-up is still required to establish an evaluation of the long-term safety.