Irreversible electroporation ablation against subcutaneously implanted VX₂ tumors in rabbits: findings of shearwave ultrasound elastography

Purpose: This study aimed to evaluate stiffness changes of rabbit subcutaneous VX₂ tumors before and after irreversible electroporation (IRE) ablationby shearwave ultrasound elastography (SWE).

Methods: IRE was performed on 20 subcutaneously implanted VX₂ tumors in rabbits (R-SIVX₂). Tumor stiffness was measured by SWE at different time points (before IRE,120minutes after IRE,7 days after IRE and 14 days after IRE).

Results: Before IRE, the mean stiffness (E_mean) of tumors was (10.45 ± 1.07) KPa. 120 minutes after I RE, the E_mean of tumors obviously rose to (70.53 ± 9.87) KPa. 7 days after IRE, the E_mean of tumors decreased to (40.22 ± 9.01) KPa. 14 days after IRE, the E_mean of tumors was (15.17 ± 1.00) KPa. A clear boundary was observed between the ablation area and the normal tissues in the pathological results.

Conclusions: The stiffness of the VX₂ tumors experienced a first rise process and tend to be normal in the procedure of IRE. SWE could provide tissue stiffness information of different IRE ablation period as a non-invasive method.