Evaluation for real-time elastography versus shear wave elastography on the ablation zone of rabbit liver: a preliminary experimental study

Abstract

Objective To comparatively evaluate the ablation zone of rabbit liver with real-time elastography (RTE) and shear wave elastography (SWE). Methods A unipolar internal cooled radiofrequency probe was used to form the ablation zone for ten rabbit liver. After the ablation, RTE and SWE were used to measure the value of elastography. Contrast enhanced ultrasound was also used to assess the ablation zone. The value of elastography from these two methods and the scope of ablation zone among the CEUS images, samples and elastography images were compared, respectively. Results RTE and SWE could display the scope of ablation zone just after the ablation. RTE image could get the ratio of the ablation zone and the surrounding liver which was 3.22±0.70. SWE could display the value of elasticity decreased from the center to the edge of ablation zone. The value of elasticity for the center and the rim of ablation zone were (51.1±11.5)kPa and (29.70±3.28)kPa. The area of ablation zone for RTE and SWE were (1.087±0.179)cm2 and (1.058±0.219)cm2. There were no difference in the ablation area among RTE, SWE and the gross specimen (P>0.05). CEUS displayed non-enhancement for ablation zone, but the area of ablation zone was larger than those from gross sample (P<0.05). Conclusions RTE and SWE could confirm the scope of ablation zone. And the SWE provides the guidance for confirming the boundary of ablation zone for the future clinical application. Key words: Shear wave elastography; Real-time elastography; Radiofrequency ablation; Liver