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Updated: Feb 16, 2026
Contrast Enhanced Vessel Imaging using MicroCT
Published on: January 27, 2011
Quantitative Flow Imaging in Human Umbilical Vessels In Utero Using Nongated 2D Phase Contrast MRI
Uday Krishnamurthy1,2, Brijesh K Yadav1,2, Pavan K Jella1
1Department of Radiology, Wayne State University School of Medicine, Detroit, Michigan, USA.
Background:
Volumetric assessment of afferent blood flow rate provides a measure of global organ perfusion. Phase-contrast magnetic resonance imaging (PCMRI) is a reliable tool for volumetric flow quantification, but given the challenges with motion and lack of physiologic gating signal, such studies, in vivo on the human placenta, are scant.
Purpose:
To evaluate and apply a nongated (ng) PCMRI technique for quantifying blood flow rates in utero in umbilical vessels.
Study Type:
Prospective study design.
Study Population:
Twenty-four pregnant women with median gestational age (GA) 30 4/7 weeks and interquartile range (IQR) 8 1/7 weeks.
Field Strength/Sequence:
All scans were performed on a 3.0T Siemens Verio system using the ng-PCMRI technique.
Assessment:
The GA-dependent increase in umbilical vein (UV) and arterial (UA) flow was compared to previously published values. Systematic error to be expected from ng-PCMRI, in the context of pulsatile UA flow and partial voluming, was studied through Monte-Carlo simulations, as a function of resolution and number of averages.
Statistical Tests:
Correlation between the UA and UV was evaluated using a generalized linear model.
Results:
Simulations showed that ng-PCMRI measurement variance reduced by increasing the number of averages. For vessels on the order of 2 voxels in radius, partial voluming led to 10% underestimation in the flow. In fetuses, the average flow rates in UAs and UV were measured to be 203 ± 80 ml/min and 232 ± 92 ml/min and the normalized average flow rates were 140 ± 59 ml/min/kg and 155 ± 57 ml/min/kg, respectively. Excellent correlation was found between the total arterial flow vs. corresponding venous flow, with a slope of 1.08 (P = 0.036).
Data Conclusion:
Ng-PCMRI can provide accurate volumetric flow measurements in utero in the human umbilical vessels. Care needs to be taken to ensure sufficiently high-resolution data are acquired to minimize partial voluming-related errors.
Level Of Evidence:
2 Technical Efficacy Stage 1 J. Magn. Reson. Imaging 2017.
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