Assessing within-subject rates of change of placental MRI diffusion metrics in normal pregnancy

TY - JOUR

T1 - Assessing within-subject rates of change of placental MRI diffusion metrics in normal pregnancy

AU - Cromb, Daniel

AU - Slator, Paddy J.

AU - De la Fuente Botella, Miguel

AU - Price, Anthony

AU - Rutherford, Mary

AU - Counsell, Serena

AU - Hutter, Jana

N1 - Funding Information: We are extremely grateful to all participants who generously gave up their time to undergo placental MRI for this study. We are also grateful to radiographers Emer Hughes, Massimo Marenzana, Katie Colford, Peter Murkin, Louise Dillon, and Elaine Green for their assistance with ensuring all imaging was performed successfully; to Tomoki Arichi, Jennie Almalbmis, Rebe Martinez-Gonzalez, Joanna Robinson, Megan Quirke, Paul Cawley, and Alessandra Maggioni for their support in the Evelina Newborn Imaging Centre; and to Megan Brace, Stefanie Chan, Michelle Jiang, and Zoe Hesketh for their assistance with study recruitment and administration. Funding Information: This work was supported by grants from the Medical Research Council (MRC) UK, grant (MR/V002465/1); core funding from the Welcome/Engineering and Physical Sciences Research Council (EPSRC) Centre for Medical Engineering, grant (WT203148/Z/16/Z); the National Institutes of Health (NIH), the National Institute of Child Health and Development (NICHD) Human Placenta Project, grant [1U01HD087202‐01]; EPSRC grant EP/V034537/1. j.h . was also supported by a Welcome Trust Sir Henry Welcome Fellowship [201374/Z/16/Z] and a UK Research and Innovation (UKRI) Future Leaders Fellowships (FLF), grant [MR/T018119/1]. The views expressed are those of the authors and not necessarily those of the NHS, the National Institute for Health Research, or the Department of Health. Publisher Copyright: © 2023 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals LLC on behalf of International Society for Magnetic Resonance in Medicine.

PY - 2023/9

Y1 - 2023/9

N2 - Purpose: Studying placental development informs when development is abnormal. Most placental MRI studies are cross-sectional and do not study the extent of individual variability throughout pregnancy. We aimed to explore how diffusion MRI measures of placental function and microstructure vary in individual healthy pregnancies throughout gestation. Methods: Seventy-nine pregnant, low-risk participants (17 scanned twice and 62 scanned once) were included. T2-weighted anatomical imaging and a combined multi-echo spin-echo diffusion-weighted sequence were acquired at 3 T. Combined diffusion–relaxometry models were performed using both a (Figure presented.) -ADC and a bicompartmental (Figure presented.) -intravoxel-incoherent-motion ((Figure presented.)) model fit. Results: There was a significant decline in placental (Figure presented.) and ADC (both P < 0.01) over gestation. These declines are consistent in individuals for (Figure presented.) (covariance = −0.47), but not ADC (covariance = −1.04). The (Figure presented.) model identified a consistent decline in individuals over gestation in (Figure presented.) from both the perfusing and diffusing placental compartments, but not in ADC values from either. The placental perfusing compartment fraction increased over gestation (P = 0.0017), but this increase was not consistent in individuals (covariance = 2.57). Conclusion: Whole placental (Figure presented.) and ADC values decrease over gestation, although only (Figure presented.) values showed consistent trends within subjects. There was minimal individual variation in rates of change of (Figure presented.) values from perfusing and diffusing placental compartments, whereas trends in ADC values from these compartments were less consistent. These findings probably relate to the increased complexity of the bicompartmental (Figure presented.) model, and differences in how different placental regions evolve at a microstructural level. These placental MRI metrics from low-risk pregnancies provide a useful benchmark for clinical cohorts.

AB - Purpose: Studying placental development informs when development is abnormal. Most placental MRI studies are cross-sectional and do not study the extent of individual variability throughout pregnancy. We aimed to explore how diffusion MRI measures of placental function and microstructure vary in individual healthy pregnancies throughout gestation. Methods: Seventy-nine pregnant, low-risk participants (17 scanned twice and 62 scanned once) were included. T2-weighted anatomical imaging and a combined multi-echo spin-echo diffusion-weighted sequence were acquired at 3 T. Combined diffusion–relaxometry models were performed using both a (Figure presented.) -ADC and a bicompartmental (Figure presented.) -intravoxel-incoherent-motion ((Figure presented.)) model fit. Results: There was a significant decline in placental (Figure presented.) and ADC (both P < 0.01) over gestation. These declines are consistent in individuals for (Figure presented.) (covariance = −0.47), but not ADC (covariance = −1.04). The (Figure presented.) model identified a consistent decline in individuals over gestation in (Figure presented.) from both the perfusing and diffusing placental compartments, but not in ADC values from either. The placental perfusing compartment fraction increased over gestation (P = 0.0017), but this increase was not consistent in individuals (covariance = 2.57). Conclusion: Whole placental (Figure presented.) and ADC values decrease over gestation, although only (Figure presented.) values showed consistent trends within subjects. There was minimal individual variation in rates of change of (Figure presented.) values from perfusing and diffusing placental compartments, whereas trends in ADC values from these compartments were less consistent. These findings probably relate to the increased complexity of the bicompartmental (Figure presented.) model, and differences in how different placental regions evolve at a microstructural level. These placental MRI metrics from low-risk pregnancies provide a useful benchmark for clinical cohorts.

KW - diffusion imaging

KW - longitudinal imaging

KW - placental MRI

KW - relaxometry

UR - http://www.scopus.com/inward/record.url?scp=85159362644&partnerID=8YFLogxK

U2 - 10.1002/mrm.29665

DO - 10.1002/mrm.29665

M3 - Article

C2 - 37183839

AN - SCOPUS:85159362644

SN - 0740-3194

VL - 90

SP - 1137

EP - 1150

JO - Magnetic Resonance in Medicine

JF - Magnetic Resonance in Medicine

IS - 3

ER -