时间-空间相关成像-M超在测定胎儿左心室短轴缩短率中的应用

Application of spatio-temporal image with M-mode display in measuring fetal fractional shortening of left ventricular

目的探讨胎儿心脏实时三维超声时间-空间相关成像-M超(STIC-M超)在测定中孕期胎儿左心室短轴缩短率(LVFS)中的应用。方法使用STIC技术取得胎儿心脏的容积数据,利用离线分析软件对容积数据进行STIC-M超分析处理,获得胎儿心脏的M超曲线图,在其上测量左心室的舒张末期内径(LVIDd)与收缩末期内径(LVIDs),利用公式LVFS=(LVIDd-LVIDs)/LVIDd×100%计算LVFS,与传统方法获得的LVFS进行对照。结果对于获取图像质量较满意的65例胎儿进行均数比较发现:STIC-M超所得到的LVFS为:33.20%±7.06%,传统M超测得的LVFS为33.86%±5.33%。通过两组间数据Pearson相关性进行统计分析,相关系数r=0.927,P=0.000,通过Bland-Altman分析,两种方法间95%一致性界限为(4.98%,-6.25%)。使用STIC-M超测量LVFS,观察者间及观察者内ICC值分别为0.877、0.845,而通过传统方法测量者间及测量者内的ICC分别为0.794、0.780。结论 STIC-M超可用LVFS测量,与传统M超测量具有相关性,且较传统M超更准确、重复性更好,具有明显的优势,其可在离线状态下,更方便地进行胎儿的LVFS测定。

Objective To investigate the value of clinical application of spatio-temporal image correlation （STIC） with M-mode display （STIC-M） measuring the fetal fxactional shortening （LVFS） of left ventricular at the maternal gestation. Methods STIC technology was used to obtain volume data of fetal heart, these data were analysed with STIC-M by use of off-line analysis software, left ventricular end diastolic diameter （LVIDd） and in the end systolic diameter （LVIDs） were measured in STIC-M mode using 4D view software, and calculated LVFS using the formula LVFS=（LVIDd-LVIDs）/LVIDd×100%. And the data get by the traditional M-mode were compared. Results In 65 cases of fetus obtained satisfactory image, LVFS measured by STIC-M mode was： 33.20%±7.06%, while LVFS measured by the traditional M-mode was 33.86%±5.33%. There was a correlation between the two values （Pearson＇s correlation coefficient, r=0.927, P=-0.000） and the 95% limits of agreement of these two methods was （4.98%, -6.25%）. Interobserver and intraobserver correlations were 0.877 and 0.845 by STIC M-mode and 0.794 and 0.780 by traditional M-mode respectively. Conclusion STIC M-mode can be used for fetal LVFS measurement with advantages of off-line analysis, good reproducibility and accuracy as compared to the traditional M-mode ultrasound.