నైరూప్య

Experimental study of applying shear wave elastography for examining effects of high intensity focused ultrasound ablation against subcutaneously implanted VX2 tumors in rabbits

Fei Chen, Sheng Li, Limei Wu, Jianzhong Zou, Shaodong Qiu, Quanshi Wang

The aims of this study were to investigate the feasibility of applying Shear Wave Elastography (SWE) to evaluate the effects of High Intensity Focused Ultrasound (HIFU) ablation on Subcutaneously Implanted VX₂ tumors in rabbits (R-SIVX₂). The tumor hardness in a total of 20 R-SIVX₂ models was measured at different time points using SWE following HIFU ablation treatment. In SWE images, the VX₂ tumor appeared to be a homogeneous blue, and the average tumor hardness (E_mean) was 10.48 ± 0.33 Kpa. Tumor hardness on D1 was the highest (E_mean=97.45 ± 23.08 Kpa), and decreased gradually over a 30 d period, with tumor hardness on D30 being similar to that on D0. The hardness uniformity (ESD) in the Region of Interest (ROI) increased significantly as compared to before the ablation, indicating that HIFU ablation can cause acoustic environmental changes in the organizations of the ROI. There were significant differences among E_min, E_mean, E_max and E_SD at different time points (P=0.00). There was no significant difference in Emin (Emean) between D0 and D30 (P<0.05), but there was a significant difference between D0/D30 and D1/D7/D14 (P<0.05). The Emax values among different time points showed statistical significance (P<0.05), but the difference in ESD between D3/D7 and D0/D1/D14/D30 was statistically significant (P<0.05). In addition to 2D ultrasound and color flow signals, SWE can provide tissue hardness information when used for evaluating the efficacy of HIFU ablation, which can provide useful information for evaluating the effects of tumor ablation.