Comparison Of The Blood Flow Velocity Of The Middle Cerebral Artery And The Intra-Hepatic Umbilical Vein By Color Doppler Ultrasonography In Predicting Fetal α-Thalassemia

Objective: To investigate and compare the value of the blood flow velocity of the middle cerebral artery and the intra-hepatic umbilical vein by color Doppler ultrasonography in predicting fetalα-thalassemia.Methods: 129 pregnancies of the experiment group at risk due to fetalα-thalassemia and 44 pregnancies of the normal control, were performed with two-dimensional ultrasound and Doppler imaging. The MCA peak systolic velocity (PSV), and IHUV maximum velocity (Vmax) were measured. All fetuses of the experiment group were detectedα-thalassemia genotypes by amniocentesis or cordocentesis. Both MCA-PSV and IHUV-Vmax were expressed as multiples of the median(MOM). Evaluate and compare the value of MCA-PSV and IHUV-Vmax in predicting fetalα-thalassemia.Results: The group of fetuses with Hemoglobin Bart's Hydrops Fetalis Syndrome had significantly higher MCA-PSV, IHUV-Vmax compared to the fetuses with Hemoglobin H disease ,α-thalassemia Trait and the normal fetuses (P<0.001,P<0.05);However, there were no statistical significant difference in the MCA-PSV, IHUV-Vmax between the other groups(P>0.05). The best cut-off points of MCA-PSV and IHUV-Vmax were 1.29 MOM, 1.27MOM, respectively. The sensitivity of MCA-PSV>1.29 MOM and IHUV-Vmax >1.27MOM in prediction of Hemoglobin Bart's Hydrops Fetalis Syndrome were 81.25%, 63.33%, respectively; and the specificity were 93.62%, 75.18%, respectively. The earliest time for MCA-PSV and IHUV-Vmax to predict Hemoglobin Bart's Hydrops Fetalis Syndrome was 16 gestational weeks, earlier than the time of hydrops appeared. The sensitivity and specificity of combining MCA-PSV with IHUV-Vmax in the prediction of Hemoglobin Bart's Hydrops Fetalis Syndrome were 93.12%,98.42%, respectively. Comparing combined MCA-PSV with IHUV-Vmax and single MCA-PSV or single IHUV-Vmax, there were no statistical significant difference in the rate of reducing invasive procedure(P>0.05), but the former had lower rate of missed diagnosis of Hemoglobin Bart's Hydrops Fetalis Syndrome than the latter two(P<0.05).Conclusion: Measurement of MCA-PSV and IHUV-Vmax by Doppler ultrasound can be used to be a noninvasive tool to predict Hemoglobin Bart's Hydrops Fetalis Syndrome. MCA-PSV is an accurate parameter for the prediction of fetal anemia, better than IHUV-Vmax. Combined MCA-PSV with IHUV-Vmax could raise the sensitivity or the specificity, reduce unwanted invasive procedure and reduce the rate of missed diagnosis in prediction of Hemoglobin Bart's Hydrops Fetalis Syndrome.