Study On Acoustic Radiation Force Impulse In Assessing The Early Effects After Treatment Of HCC By Radio Frequency Ablation

Objective The aim of this study was to explore the role of acoustic radiation force impulse(ARFI)in assessing the early response after radiofrequency ablation(RFA)in hepathocellcular carcinoma(HCC).Materials and Methods A total of 22 patients with 23 HCC lesions received RFA in our hospital from December 2015 to June 2016 were included.All the patients were examined with base-line ultrasound(BUS),contrast enhanced ultrasound(CEUS)and ARFI one week before RFA,24 h after RFA and one month after RFA,respectively.Measured the long diameter and transverse diameter of the ablated lesions by BUS,CEUS and Virtual touch tissue imaging(VTI)(one week before RFA,24 h after RFA and one month after RFA)and calculated the area by ellipsoid area formula.Compared the area of ablation lesions measured by the three methods at different time points.Virtual touch tissue quantification(VTQ)was calculated to assess the interior,the margin and peripheral parts of the primarytumor.Comparedthe focal hardness changes in different areas preoperative and postoperative RFA.Results 23 tumors showed low-echo on VTI 24 h after RFA and one month after RFA,which were easily detected.The extent of ablation area was enlarged compared to preoperative.After 24 h of RFA procedure,The VTQ value of the internal and marginal of ablation lesion area was higher than preoperative(all P<0.01),respectively,but there was not statistically significantly difference in one month after RFA(P=0.46,P=0.50).The value of VTQ in peripheral parts of the primary tumor did not change significantly at one week before RFA,24 h after RFA and one month after RFA(all P>0.05).24 h after RFA and one month after RFA the ablation lesion area measured by VTI and CEUS was larger than with BUS(all P<0.01).However,There is no statistically significantly difference of ablation lesion area between VTI and CEUS(P=0.88,P=0.49).Conclusion ARFI can accurately measure the ablation area and providing the change of lesion hardness immediately after RFA of HCC.It’sa non-invasive,effective and feasible method.