Magnetic resonance imaging‐estimated placental perfusion in fetal growth assessment

Abstract

ObjectiveTo evaluate in‐vivo placental perfusion fraction, estimated by magnetic resonance imaging (MRI), as a marker of placental function.MethodsA study population of 35 pregnant women, of whom 13 had pre‐eclampsia (PE), were examined at 22–40 weeks' gestation. Within a 24‐h period, each woman underwent an MRI diffusion‐weighted sequence (from which we calculated the placental perfusion fraction), venous blood sampling and an ultrasound examination including estimation of fetal weight, amniotic fluid index and Doppler velocity measurements. The perfusion fractions in pregnancies with and without fetal growth restriction were compared and correlations between the perfusion fraction and ultrasound estimates and plasma markers were estimated using linear regression. The associations between the placental perfusion fraction and ultrasound estimates were modified by the presence of PE (P < 0.05) and therefore we included an interaction term between PE and covariates in the models.ResultsThe median placental perfusion fractions in pregnancies with and without fetal growth restriction were 21% and 32%, respectively (P = 0.005). The correlations between placental perfusion fraction and ultrasound estimates and plasma markers were highly significant (P = 0.002 and P = 0.0001, respectively). The highest coefficient of determination (R 2 = 0.56) for placental perfusion fraction was found for a model that included pulsatility index in the ductus venosus, plasma level of soluble fms‐like tyrosine kinase‐1, estimated fetal weight and presence of PE.ConclusionThe placental perfusion fraction has the potential to contribute to the clinical assessment of cases with placental insufficiency. © 2015 Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Microvascular perfusion of the placenta, developing fetal liver, and lungs assessed with intravoxel incoherent motion imaging

“…We reported a mean placental perfusion fraction of 29%, indicating that the microvascular compartment of the placenta remained consistently highly perfused during mid‐ and late‐gestation. This value is congruent with the report of Moore et al, who found a mean f of 26% and is also close to the placental f of 32% in healthy pregnancies reported by Sohlberg et al Our findings also match closely the f of the central placenta (35.1%) reported in a previous study and is lower than the mean value (42.5%) reported by Siauve et al, although our observed perfusion fraction is significantly lower than the perfusion values of the decidua basalis reported in normal and small for gestational age subjects . The perfusion fraction as previously found to be a sensitive marker of decreased placental perfusion in murine models and in human studies, and our study confirms the generally accepted range of normal placental perfusion fraction in the central parts of the placenta by means of IVIM.…”

“…27 The results of Derwig et al 21 are in line with these findings, as they investigated a relatively narrow gestational age range of 24 to 29 weeks, when, according to Siauve et al, f remains stable. 27 On the contrary, Sohlberg et al 26 reported a significant decrease of f with gestational age. We found a moderate correlation between placental f and gestational age, with increasing values over gestation.…”

“…We included in the study data from 55 IVIM imaging sessions, which were acquired for fetuses from 33 singleton pregnancies, with a mean 6 SD (range) gestational age at the time of examination of 26.8 6 3.8 (17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36) weeks. Maternal age was 32.9 6 4.7 (22.1-40.8) years at the time of the MR exam.…”

Perfusion of the placenta assessed using arterial spin labeling and ferumoxytol dynamic contrast enhanced magnetic resonance imaging in the rhesus macaque

“…This technique assumes that blood motion is incoherent over a voxel and of higher degree than surrounding tissue . The IVIM technique has been applied to placenta imaging in healthy subjects and demonstrated promise in detecting differences in the perfusion fraction in pregnancies with fetal growth restriction, small for gestational age fetuses, and in early and late preeclampsia compared with controls. In initial comparisons of placental perfusion, IVIM demonstrated a higher predictive power to reduced birthweight than ASL FAIR .…”

Semi-automatic segmentation of the placenta into fetal and maternal compartments using intravoxel incoherent motion MRI

“…The perfusion of maternal blood in the human placenta, so called placental perfusion , has a crucial role for the effective delivery of nutrients and gases to the fetus 1 . Any impedance to blood flow through the placenta compromises placental perfusion, and ultimately compromises the provision of necessary nutrients to the growing fetus 2 . Therefore, placental perfusion may be used as an early biomarker of placental dysfunction associated with fetal growth restriction (FGR).…”