Tarzamni Mohammad Kazem, Nezami Nariman, Sobhani Narges, Eshraghi Nazanin, Tarzamni Maryam, Talebi Yashar
Department of Radiology, Tabriz University of Medical Sciences, and Obstetrics and Gynecology ward, 29 Bahman Hospital, Tabriz, Iran.
BMC Pregnancy Childbirth. 2008 Nov 12;8:50. doi: 10.1186/1471-2393-8-50.
Doppler flow velocity waveform analysis of fetal vessels is one of the main methods for evaluating fetus health before labor. Doppler waves of middle cerebral artery (MCA) can predict most of the at risk fetuses in high risk pregnancies. In this study, we tried to obtain normal values and their nomograms during pregnancy for Doppler flow velocity indices of MCA in 20-40 weeks of normal pregnancies in Iranian population and compare their pattern with other countries' nomograms.
During present descriptive cross-sectional study, 1037 normal pregnant women with 20th-40th week gestational age were underwent MCA Doppler study. All cases were studied by gray scale ultrasonography initially and Doppler of MCA afterward. Resistive Index (RI), Pulsative Index (PI), Systolic/Diastolic ratio (S/D ratio), and Peak Systolic Velocity (PSV) values of MCA were determined for all of the subjects.
Results of present study showed that RI, PI, S/D ratio values of MCA decreased with parabolic pattern and PSV value increased with simple pattern, as gestational age progressed. These changes were statistically significant (P=0.000 for all of indices) and more characteristic during late weeks of pregnancy.
Values of RI, PI and S/D ratio indices reduced toward the end of pregnancy, but PSV increased. Despite the trivial difference, nomograms of various Doppler indices in present study have similar pattern with other studies.
胎儿血管的多普勒血流速度波形分析是分娩前评估胎儿健康的主要方法之一。大脑中动脉（MCA）的多普勒波可预测大多数高危妊娠中处于危险的胎儿。在本研究中，我们试图获取伊朗人群正常妊娠20至40周期间MCA多普勒血流速度指数的正常值及其列线图，并将其模式与其他国家的列线图进行比较。
在当前的描述性横断面研究中，对1037名妊娠20至40周的正常孕妇进行了MCA多普勒研究。所有病例首先通过灰阶超声检查，然后进行MCA多普勒检查。测定了所有受试者MCA的阻力指数（RI）、搏动指数（PI）、收缩/舒张比（S/D比）和收缩期峰值速度（PSV）值。
本研究结果表明，随着孕周的增加，MCA的RI、PI、S/D比值呈抛物线型下降，PSV值呈简单型增加。这些变化具有统计学意义（所有指标P = 0.000），在妊娠晚期更具特征性。
妊娠末期RI、PI和S/D比指数值降低，但PSV升高。尽管存在细微差异，但本研究中各种多普勒指数的列线图与其他研究具有相似的模式。
