速度向量成像技术对脂肪肝弹性的评价研究

PRELIMINARY INVESTIGATION OF VELOCITY VECTOR IMAGING IN THE DIAGNOSTIC VALUE OF FATTY LIVER

目的初步探讨速度向量成像技术在脂肪肝弹性评价中的应用价值。方法选择轻度、中度、重度脂肪肝患者共69例,正常对照组30例,常规超声扫查后,连接心电电极,存储肝左叶至少3个心动周期动态图像,启动自带VVI软件测量同一直线上距离膈肌1、2、3、4cm处肝组织舒张期运动最大速度(Vmax),最大应变(Smax)及最大应变率(SRmax)。结合脂肪肝超声分度标准对其参数进行分析。结果脂肪肝组与对照组肝左叶舒张期Vmax、Smax及SRmax随着距膈肌距离的增加逐渐减小;对照组与轻度脂肪肝亚组之间Vmax、Smax差异无统计学意义(P>0.05),SRmax差异具有统计学意义(P<0.05);脂肪肝轻、中、重各组之间Vmax、Smax、SRmax差异具有统计学意义(P<0.05),且随着程度加重而减小。通过ROC曲线分析,肝左叶SR4max取值为0.703(s-1)时,判断轻度脂肪肝的灵敏度为93.3%,特异度为82.6%;S1max取值为10.994(%)时,判断中度脂肪肝的灵敏度为95.7%,特异度为84.6%;V4max取值为0.352(10-2cm/s)时,判断重度脂肪肝的灵敏度为92.3%,特异度为90.0%。结论速度向量成像技术在评价脂肪肝弹性变化中具有独特的优势,对脂肪肝的定量诊断具有一定指导意义。

Objective To preliminarily investigate diagnostic value of velocity vector imaging（VVI）for fatty 1iver.Methods Sixty-nine patients with fatty liver were enrolled,and 30 patients with proven healthy livers were used as control group.After all patients with conventional ultrasound scanning,connect ECG electrodes,and store the motion pictures of the left lobe of the liver at least three cardiac cycles.VVI software was used to measure diastolic measuring the maximum velocity（Vmax）,the maximum strain（Smax）and the maximum strain rate（SRmax）from the diaphragm1 cm,2cm,3cm,4cm in a straight line.The VVI parameters combined with fatty liver ultrasound index criteria were analyzed.Results The diastolic Vmax,Smaxand SRmaxof the left hepatic lobe with increasing distance from the diaphragm were decrease in fatty liver group and the control group;The differences of Vmax,Smaxbetween the two groups were not statistically significant（P〉0.05）,the difference of SRmax was statistically significant（P〈0.05）;The differences of Vmax,Smaxand SRmaxbetween fatty liver light,medium and heavy groups were statistically significant（P〈0.05）,and decreased with the aggravation.By ROC curve analysis,SR4 maxvalue of 0.703（s-1）,the diagnosis of mild fatty liver sensitivity and specificity were 93.3%,82.6%;S1maxvalue of 10.994（%）,the diagnosis of moderate fatty liver of sensitivity,specificity,respectivelyIt was 95.7%,84.6%;V4maxvalue of0.352（10-2cm/s）,the sensitivity and specificity of diagnosis of severe fatty liver were 92.3%and 90.0%.Conclusions Velocity Vector Imaging technology has a unique advantage in the evaluation of fatty liver elasticity variation,and has some significance in quantitative diagnosis of fatty liver.