时间-空间相关成像技术对正常胎儿心脏大动脉空间角度的定量研究

目的 应用时间-空间相关成像(spatiotemporal image correlation,STIC)技术建立不同孕周胎儿心脏大动脉空间角度的正常参考值范围.方法 运用STIC采集352例孕20～38周正常胎儿的心脏三维数据,通过正交三平面模式测量标准四腔观与左室长轴观之间、左室长轴观与主肺动脉干观之间以及动脉导管弓观与主动脉弓观之间的角度.应用相关回归分析评价上述角度与孕周的相关性.结果 正常胎儿标准四腔观与左室长轴观的角度与孕周不相关(r=0.04,P=0.51),95%正常参考值范围为34.5°～56.7°.左室长轴观与主肺动脉干观之间以及动脉导管弓长轴观与主动脉弓长轴观之间的角度与孕周相关(r分别为-0.53、0.57,P＜0.001),回归方程分别为:Y=154-4.24X+0.05X2,Y=-20.8+2.65X-0.37X2.结论 STIC能定量测量20～38周胎儿心脏大动脉之间的角度并建立正常参考值范围,为产前筛查大动脉空间关系异常的先天性心脏病提供有价值的参考标准.

Abstract：

Objective To establish the reference ranges of the spatial angles among cardiac chambers and great vessels in second and third trimester fetuses measured by spatiotemporal image correlation (STIC).Methods Volume images of 352 normal fetuses from 20 to 38 weeks of gestation were recruited in the study.An off-line analysis of acquired volume datasets was carried out with multiplanar mode.Parameters measured included angles between:(1) the 4-chamber view and the left ventricular long axis view; (2) the left ventricular long axis view and main pulmonary artery; and (3) the ductal arch and aortic arch.The relationships between above-mentioned angles and gestational age were assessed by correlation and regression analysis.Results The angle between the 4-chamber view and the left ventricular long axis view (range:55.7° - 35.7°,mean:45.7° ± 5.12°) was uncorrelated with gestational age (r = 0.03,P = 0.51).In contrast,the angle between the left ventricular long axis view and main pulmonary artery,and the angle between the ductal arch and aortic arch were correlated with gestational age (P ＜ 0.001),and the correlation coefficient was - 0.53 and 0.57 respectively.The best-fit exponential curve regression equations of the angle between the left ventricular long axis view and main pulmonary artery was:Y = 154- 4.24X +0.05X2 ,and the angle between the ductal arch and aortic arch was:Y = - 20.8 + 2.65X - 0.37X2.Conclusions The angles among cardiac chambers and great arteries of fetuses from 20 to 38 weeks of gestation can be quantitatively measured by STIC.The reference ranges provide a reliable quantitative standard to estimate the spatial relationships of the cardiac large arteries of fetuses,which may be clinically useful in prenatal screening congenital heart disease.

Quantitative study of the spatial angles among cardiac chambers and great vessels in the normal fetuses by spatiotemporal image correlation

Objective To establish the reference ranges of the spatial angles among cardiac chambers and great vessels in second and third trimester fetuses measured by spatiotemporal image correlation (STIC).Methods Volume images of 352 normal fetuses from 20 to 38 weeks of gestation were recruited in the study.An off-line analysis of acquired volume datasets was carried out with multiplanar mode.Parameters measured included angles between:(1) the 4-chamber view and the left ventricular long axis view; (2) the left ventricular long axis view and main pulmonary artery; and (3) the ductal arch and aortic arch.The relationships between above-mentioned angles and gestational age were assessed by correlation and regression analysis.Results The angle between the 4-chamber view and the left ventricular long axis view (range:55.7° - 35.7°,mean:45.7° ± 5.12°) was uncorrelated with gestational age (r = 0.03,P = 0.51).In contrast,the angle between the left ventricular long axis view and main pulmonary artery,and the angle between the ductal arch and aortic arch were correlated with gestational age (P ＜ 0.001),and the correlation coefficient was - 0.53 and 0.57 respectively.The best-fit exponential curve regression equations of the angle between the left ventricular long axis view and main pulmonary artery was:Y = 154- 4.24X +0.05X2 ,and the angle between the ductal arch and aortic arch was:Y = - 20.8 + 2.65X - 0.37X2.Conclusions The angles among cardiac chambers and great arteries of fetuses from 20 to 38 weeks of gestation can be quantitatively measured by STIC.The reference ranges provide a reliable quantitative standard to estimate the spatial relationships of the cardiac large arteries of fetuses,which may be clinically useful in prenatal screening congenital heart disease.