Z-scores in evaluation of aortic and pulmonary diameter growth in normal fetuses of second and late trimesters / 中国医学影像技术

ABSTRACT

Objective To explore the application value of Z-scores in evaluating growth of aorta (AO) and pulmonary artery (PA) diameter.Methods AO and PA diameters in 332 normal fetuses were measured twice using fetal echocardiography.Z-scores of AO and PA were obtained based on a simple linear equation using gestational age (GA),biparietal diameter (BPD) and femur length (FL) as independent variables.The difference of Z-scores calculated by twice examinations was evaluated.Results The gestation ages of the first and the second examinations of fetal echocardiography were (25.82± 2.27) weeks (range 18-35 weeks) and (30.61± 2.28) weeks (range 23-39 weeks).There were statistical significant differences of AO and PA diameters between the first and the second examinations (both P＜0.05).AO and PA diameters increased with the growth of GA in all fetuses obtained using two examinations,whereas there was no obvious change of Zscores of AO and PA with increasing GA,BPD and FL in individual pregnant woman.No statistical significant difference was found for Z-scores of AO and PA between the first and the second examinations (both P＞0.05).Conclusion The growth of AO and PA diameters are positively correlated with the growth of biological parameters in normal fetuses,while Z-scores of AO and PA remain constant in second and late trimesters.