Department of Radiology, University of Michigan, Ann Arbor, MI, USA.
Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, MI, USA.
J Ultrasound Med. 2022 Oct;41(10):2445-2457. doi: 10.1002/jum.15927. Epub 2021 Dec 21.
Placental blood flow analysis is complicated by having both maternal and fetal flow components. Using the Fast Fourier Transform (FFT) of the umbilical venous pulse wave spectra (PW) envelope, we could simultaneously assess maternal/fetal blood flow in the placenta and investigate if normal and intrauterine growth restriction (IUGR)/pre-eclamptic pregnancies could be distinguished.
This retrospective study included normal gestations (N = 11) and gestations with IUGR, pre-eclampsia, or both (N = 13). Umbilical vein PW were acquired and spectral envelopes were identified as a function of time and analyzed by FFT. Base-10 logarithms of the ratios of the maternal/fetal spectral peaks (LRSP) were compared in normal and IUGR/pre-eclamptic populations (two-tailed t-test). Body mass index (BMI), gestational age at scan time, placental position, and weight-normalized umbilical vein blood volume flow (two-tailed t-test, analysis of variance [ANOVA] analysis) were tested. P < .05 was considered significant.
The LRSP for normal and IUGR/pre-eclamptic pregnancies were 0.141 ± 0.180 and -0.072 ± 0.262 (mean ± standard deviation), respectively (P = .033). We detected differences between normal gestations and combinations of LRSP and weight-normalized umbilical venous blood flows. Placental effects based on LRSPs and blood flow may act synergistically in cases with both pre-eclampsia and IUGR (P = .014). No other significant associations were seen.
In this preliminary study, we showed that umbilical venous flow contains markers related to placental maternal/fetal blood flow, which can be used to assess IUGR and pre-eclampsia. When coupled with umbilical cord blood flow, this new marker may potentially identify the primary causes of the two conditions.
胎盘血流分析较为复杂，因为其包含母体和胎儿的血流成分。我们通过对脐静脉脉冲波谱（PW）包络的快速傅里叶变换（FFT），可以同时评估胎盘的母体/胎儿血流，并研究正常妊娠与宫内生长受限（IUGR）/子痫前期妊娠是否可以区分。
本回顾性研究纳入了正常妊娠（N=11）和 IUGR、子痫前期或两者并存的妊娠（N=13）。采集脐静脉 PW，确定时间相关的频谱包络，并通过 FFT 进行分析。比较正常和 IUGR/子痫前期人群中母体/胎儿频谱峰值的对数比（LRSP）（双侧 t 检验）。测试体质量指数（BMI）、扫描时的孕周、胎盘位置和体重归一化脐静脉血流容积（双侧 t 检验、方差分析[ANOVA]分析）。P<.05 为差异有统计学意义。
正常妊娠和 IUGR/子痫前期妊娠的 LRSP 分别为 0.141±0.180 和-0.072±0.262（均值±标准差）（P=0.033）。我们在正常妊娠和 LRSP 与体重归一化脐静脉血流的组合之间检测到差异。基于 LRSP 和血流的胎盘效应在子痫前期和 IUGR 并存的情况下可能具有协同作用（P=0.014）。未发现其他显著相关性。
在这项初步研究中，我们表明脐静脉血流中包含与胎盘母体/胎儿血流相关的标志物，可用于评估 IUGR 和子痫前期。当与脐带血流结合时，这种新标志物可能有潜力识别这两种情况的主要病因。
