实时剪切波弹性成像在肝癌热消融应用中的初步体会

背景与目的：热消融[射频消融(radiofrequency ablation，RFA)和微波消融(microwave ablation，MWA)]是治疗肝癌最常用的微创技术，实时剪切波弹性成像(real-time shear wave elastography，SWE)是一种新型的超声弹性成像技术。本研究将SWE应用于肝癌热消融中，旨在研究肝癌热消融前后病灶及其周围肝实质的硬度变化，初步探讨SWE在肝癌热消融疗效评价中的应用价值。方法：2014年10月—2015年4月因肝癌于哈尔滨医科大学附属肿瘤医院行超声引导下RFA或MWA且达到完全消融的36例患者(共39个病灶)。患者于消融前后分别行SWE检查，分别记录病灶及其周围肝实质的杨氏模量平均值(SWE-mean)、最小值(SWE-min)、最大值(SWE-max)、标准差(SWE-SD)。经统计学分析，比较消融前后病灶及其周围肝实质的硬度变化及两种消融方式下消融灶的硬度差异。结果：①消融前后，病灶的SWE-mean为(30.09±11.67)kPa vs (52.11±17.56)kPa，SWE-min为(10.46±8.22)kPavs (20.57±11.42)kPa，SWE-max为(51.50±20.84)kPa vs (88.54±27.75)kPa，SWE-SD为(10.63±4.30)kPavs (16.89±7.72)kPa，差异有统计学意义(P＜0.05)；②消融前后，病灶周围肝实质的SWE-mean为(8.84±2.82)kPavs (8.91±2.78)kPa，SWE-min为(4.77±1.95) kPavs (4.69±1.90)kPa，SWE-max为(13.82±3.79)kPavs (14.34±3.97)kPa，SWE-SD为(3.24±1.32)kPa vs(3.37±1.29)kPa，差异无统计学意义(P＞0.05)；③消融后，RFA及MWA的SWE-mean为(45.55±10.91)kPa vs (60.59±20.99)kPa,SWE-min为(18.95±8.86)kPavs (25.93±10.93)kPa,SWE-max为(76.58±15.51)kPavs (104.01±32.59)kPa,SWE-SD为(13.82±3.52)kPavs (20.85±9.77)kPa，差异有统计学意义(P＜0.05)。结论：SWE可以定量评价病灶的硬度，消融后病灶硬度大于消融前，MWA后消融灶硬度大于RFA后，两种消融方式对病灶周围肝实质的硬度影响不明显。SWE在肝癌热消融中的应用前景可期。

Preliminary experience with real-time shear wave elastography monitoring of thermal ablation of liver cancer

Background and purpose:Thermal ablation (radiofrequency ablation, RFA/microwave ablation, MWA) is the most commonly used minimally invasive technique for the treatment of liver cancer. Real-time shear wave elastography (SWE) is a new type of ultrasonic imaging technology, which was used in our study to monitor thermal ablation of liver cancer. This study aimed to investigate the stiffness change of liver cancer and that of surrounding liver parenchyma before and after thermal ablation, and to evaluate the application of SWE for monitoring thermal ablation for liver cancer.Methods:From Oct. 2014 to Apr. 2015, a total number of 36 patients, with 39 lesions, were treated with RFA or MWA and got complete response. SWE examination was performed before and after ablation. The SWE-mean, SWE-min, SWE-max, SWE-SD of lesions and the surrounding liver parenchyma were measured. Statistical analysis was made to compare the stiffness changes of liver cancer with those of the surrounding liver parenchyma before and after thermal ablation, and to determine whether there were differences between two different ablation modes.Results:Before and after ablation, the SWE-mean of lesions was (30.09±11.67) kPavs (52.11±17.56) kPa,SWE-min was (10.46±8.22) kPavs (20.57±11.42) kPa, SWE-max was (51.50±20.84) kPavs (88.54±27.75) kPa, SWE-SD was (10.63±4.30) kPavs (16.89±7.72) kPa; There were statistically signiifcant differences (P<0.05). Before and after ablation, the SWE-mean of surrounding liver parenchyma was (8.84±2.82) kPavs (8.91±2.78) kPa, SWE-min was (4.77±1.95) kPavs (4.69±1.90) kPa, SWE-max was (13.82±3.79) kPavs (14.34±3.97) kPa, SWE-SD was (3.24±1.32) kPavs (3.37±1.29) kPa; There were no statistically signiifcant differences (P>0.05). After ablation, the SWE-mean of RFA and MWA was (45.55±10.91) kPavs (60.59±20.99) kPa, SWE-min was (18.95±8.86) kPavs (25.93±10.93) kPa, SWE-max was (76.58±15.51) kPavs (104.01±32.59) kPa, SWE-SD was (13.82±3.52) kPavs (20.85±9.77) kPa; There were statistically signiifcant differences (P<0.05).Conclusion:SWE can quantitively analyze the stiffness of lesions. The ablation zone became stiffer after RFA or MWA, and the ablation zone of MWA was stiffer than that of RFA. Two kinds of ablation methods did not signiifcantly affect the stiffness of liver parenchyma around the lesion. SWE could potentially be used to monitor thermal ablation of liver cancer.