1
|
Noble RMN, Kirschenman R, Wiedemeyer A, Patel V, Rachid JJ, Zemp RJ, Davidge ST, Bourque SL. Use of Photoacoustic Imaging to Study the Effects of Anemia on Placental Oxygen Saturation in Normoxic and Hypoxic Conditions. Reprod Sci 2024; 31:966-974. [PMID: 38012522 DOI: 10.1007/s43032-023-01395-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 10/23/2023] [Indexed: 11/29/2023]
Abstract
We aimed to evaluate fetal and placental oxygen saturation (sO2) in anemic and non-anemic pregnant rats throughout gestation using photoacoustic imaging (PAI). Female Sprague-Dawley rats were fed an iron-restricted or iron-replete diet before and during pregnancy. On gestational days 13, 18, and 21, PAI was coupled with high resolution ultrasound to measure oxygenation of the fetus, whole placenta, mesometrial triangle, as well as the maternal and fetal faces of the placenta. PAI was performed in 3D, which allowed sO2 to be measured within an entire region, as well as in 2D, which enabled sO2 measurements in response to a hypoxic event in real time. Both 3D and 2D PAI were performed at varying levels of FiO2 (fraction of inspired oxygen). Iron restriction caused anemia in dams and fetuses, a reduction in fetal body weight, and an increase in placental weight, but overall had minimal effects on sO2. Reductions in FiO2 caused corresponding reductions in sO2 which correlated to the severity of the hypoxic challenge. Regional differences in sO2 were evident within the placenta and between the placenta and fetus. In conclusion, PAI enables non-invasive measurement of sO2 both rapidly and with a high degree of sensitivity. The lack of overt changes in sO2 levels between control and anemic fetuses may suggest reduced oxygen extraction and utilization in the latter group, which could be attributed to compensatory changes in growth and developmental trajectories.
Collapse
Affiliation(s)
- Ronan M N Noble
- Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada
- Cardiovascular Research Institute, University of Alberta, Edmonton, AB, Canada
- Department of Pediatrics, University of Alberta, Edmonton, AB, Canada
| | - Raven Kirschenman
- Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada
- Department of Obstetrics and Gynecology, University of Alberta, Edmonton, AB, Canada
| | - Alyssa Wiedemeyer
- Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada
- Cardiovascular Research Institute, University of Alberta, Edmonton, AB, Canada
- Department of Pediatrics, University of Alberta, Edmonton, AB, Canada
| | - Vaishvi Patel
- Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada
| | - Jad-Julian Rachid
- Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada
- Cardiovascular Research Institute, University of Alberta, Edmonton, AB, Canada
- Department of Pediatrics, University of Alberta, Edmonton, AB, Canada
| | - Roger J Zemp
- Cardiovascular Research Institute, University of Alberta, Edmonton, AB, Canada
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB, Canada
| | - Sandra T Davidge
- Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada
- Cardiovascular Research Institute, University of Alberta, Edmonton, AB, Canada
- Department of Obstetrics and Gynecology, University of Alberta, Edmonton, AB, Canada
- Department of Physiology, University of Alberta, Edmonton, AB, Canada
| | - Stephane L Bourque
- Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada.
- Cardiovascular Research Institute, University of Alberta, Edmonton, AB, Canada.
- Department of Pediatrics, University of Alberta, Edmonton, AB, Canada.
- Department of Physiology, University of Alberta, Edmonton, AB, Canada.
- Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, AB, Canada.
| |
Collapse
|
2
|
Herrera CL, Kim MJ, Do QN, Owen DM, Fei B, Twickler DM, Spong CY. The human placenta project: Funded studies, imaging technologies, and future directions. Placenta 2023; 142:27-35. [PMID: 37634371 DOI: 10.1016/j.placenta.2023.08.067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 08/16/2023] [Accepted: 08/19/2023] [Indexed: 08/29/2023]
Abstract
The placenta plays a critical role in fetal development. It serves as a multi-functional organ that protects and nurtures the fetus during pregnancy. However, despite its importance, the intricacies of placental structure and function in normal and diseased states have remained largely unexplored. Thus, in 2014, the National Institute of Child Health and Human Development launched the Human Placenta Project (HPP). As of May 2023, the HPP has awarded over $101 million in research funds, resulting in 41 funded studies and 459 publications. We conducted a comprehensive review of these studies and publications to identify areas of funded research, advances in those areas, limitations of current research, and continued areas of need. This paper will specifically review the funded studies by the HPP, followed by an in-depth discussion on advances and gaps within placental-focused imaging. We highlight the progress within magnetic reasonance imaging and ultrasound, including development of tools for the assessment of placental function and structure.
Collapse
Affiliation(s)
- Christina L Herrera
- Department of Obstetrics and Gynecology, UT Southwestern Medical Center, and Parkland Health Dallas, Texas, USA; Green Center for Reproductive Biology Sciences, UT Southwestern Medical Center, Dallas, TX, USA.
| | - Meredith J Kim
- University of Texas Southwestern Medical School, Dallas, TX, USA
| | - Quyen N Do
- Department of Radiology, UT Southwestern Medical Center, Dallas, TX, USA
| | - David M Owen
- Department of Obstetrics and Gynecology, UT Southwestern Medical Center, and Parkland Health Dallas, Texas, USA; Green Center for Reproductive Biology Sciences, UT Southwestern Medical Center, Dallas, TX, USA
| | - Baowei Fei
- Department of Radiology, UT Southwestern Medical Center, Dallas, TX, USA; Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX, USA; Department of Bioengineering, University of Texas at Dallas, Dallas, TX, USA
| | - Diane M Twickler
- Department of Obstetrics and Gynecology, UT Southwestern Medical Center, and Parkland Health Dallas, Texas, USA; Department of Radiology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Catherine Y Spong
- Department of Obstetrics and Gynecology, UT Southwestern Medical Center, and Parkland Health Dallas, Texas, USA
| |
Collapse
|
3
|
Chappell J, Aughwane R, Clark AR, Ourselin S, David AL, Melbourne A. A review of feto-placental vasculature flow modelling. Placenta 2023; 142:56-63. [PMID: 37639951 PMCID: PMC10873207 DOI: 10.1016/j.placenta.2023.08.068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 08/18/2023] [Accepted: 08/20/2023] [Indexed: 08/31/2023]
Abstract
The placenta provides the vital nutrients and removal of waste products required for fetal growth and development. Understanding and quantifying the differences in structure and function between a normally functioning placenta compared to an abnormal placenta is vital to provide insights into the aetiology and treatment options for fetal growth restriction and other placental disorders. Computational modelling of blood flow in the placenta allows a new understanding of the placental circulation to be obtained. This structured review discusses multiple recent methods for placental vascular model development including analysis of the appearance of the placental vasculature and how placental haemodynamics may be simulated at multiple length scales.
Collapse
Affiliation(s)
- Joanna Chappell
- School of Biomedical Engineering and Imaging Sciences (BMEIS), King's College, London, UK.
| | - Rosalind Aughwane
- Elizabeth Garrett Anderson Institute for Women's Health, University College, London, UK
| | | | - Sebastien Ourselin
- School of Biomedical Engineering and Imaging Sciences (BMEIS), King's College, London, UK
| | - Anna L David
- Elizabeth Garrett Anderson Institute for Women's Health, University College, London, UK
| | - Andrew Melbourne
- School of Biomedical Engineering and Imaging Sciences (BMEIS), King's College, London, UK
| |
Collapse
|
4
|
Mahadevan A, Tipler A, Jones H. Shared developmental pathways of the placenta and fetal heart. Placenta 2023; 141:35-42. [PMID: 36604258 DOI: 10.1016/j.placenta.2022.12.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 12/14/2022] [Accepted: 12/21/2022] [Indexed: 12/28/2022]
Abstract
Congenital heart defects (CHD) remain the most common class of birth defect worldwide, affecting 1 in every 110 live births. A host of clinical and morphological indicators of placental dysfunction are observed in pregnancies complicated by fetal CHD and, with the recent emergence of single-cell sequencing capabilities, the molecular and physiological associations between the embryonic heart and developing placenta are increasingly evident. In CHD pregnancies, a hostile intrauterine environment may negatively influence and alter fetal development. Placental maldevelopment and dysfunction creates this hostile in-utero environment and may manifest in the development of various subtypes of CHD, with downstream perfusion and flow-related alterations leading to yet further disruption in placental structure and function. The adverse in-utero environment of CHD-complicated pregnancies is well studied, however the specific etiological role that the placenta plays in CHD development remains unclear. Many mouse and rat models have been used to characterize the relationship between CHD and placental dysfunction, but these paradigms present substantial limitations in the assessment of both the heart and placenta. Improvements in non-invasive placental assessment can mitigate these limitations and drive human-specific investigation in relation to fetal and placental development. Here, we review the clinical, structural, and molecular relationships between CHD and placental dysfunction, the CHD subtype-dependence of these changes, and the future of Placenta-Heart axis modeling and investigation.
Collapse
Affiliation(s)
- Aditya Mahadevan
- Physiology and Aging, University of Florida College of Medicine, USA; Center for Research in Perinatal Outcomes, University of Florida, USA
| | - Alyssa Tipler
- Physiology and Aging, University of Florida College of Medicine, USA; Center for Research in Perinatal Outcomes, University of Florida, USA
| | - Helen Jones
- Physiology and Aging, University of Florida College of Medicine, USA; Center for Research in Perinatal Outcomes, University of Florida, USA.
| |
Collapse
|
5
|
Lewis RM. Volume electron microscopy reveals placental ultrastructure in 3D. Placenta 2023; 141:78-83. [PMID: 37487796 DOI: 10.1016/j.placenta.2023.07.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 07/18/2023] [Accepted: 07/19/2023] [Indexed: 07/26/2023]
Abstract
Many structures necessary for placental function can only be visualised at the ultrastructural scale. Recent technological advances have made Volume electron microscopy (volume EM) approaches much more accessible. Volume EM allows the ultrastructure of tissues, cells and organelles to be visualised in 3D. It also allows the 3D spatial relationships between these structures to be determined. This review will highlight the potential for volume EM to advance our understanding of placental ultrastructure. It will focus on the human term placenta highlighting key findings spanning the placental barrier from trans-syncytial nanopores in the syncytiotrophoblast to tunnelling nanotubes in the fetal capillary endothelium. Volume EM is advancing our understanding of placental ultrastructure, but to fully exploit its potential, it will be necessary to use it as part of multimodal and correlative workflows. The complementary strengths of these different approaches can complement volume EM and reveal the biological significance of its novel observations. The use of volume EM also highlighted how ultrastructural features might underpin pregnancy pathologies and demonstrates the need for more research in this underrepresented area.
Collapse
|
6
|
Cromb D, Slator PJ, De La Fuente M, Price AN, Rutherford M, Egloff A, Counsell SJ, Hutter J. Assessing within-subject rates of change of placental MRI diffusion metrics in normal pregnancy. Magn Reson Med 2023; 90:1137-1150. [PMID: 37183839 PMCID: PMC10962570 DOI: 10.1002/mrm.29665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 03/14/2023] [Accepted: 03/22/2023] [Indexed: 05/16/2023]
Abstract
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 aT 2 * $$ {\mathrm{T}}_2^{\ast } $$ -ADC and a bicompartmentalT 2 * $$ {\mathrm{T}}_2^{\ast } $$ -intravoxel-incoherent-motion (T 2 * IVIM $$ {\mathrm{T}}_2^{\ast}\;\mathrm{IVIM} $$ ) model fit. RESULTS There was a significant decline in placentalT 2 * $$ {\mathrm{T}}_2^{\ast } $$ and ADC (both P < 0.01) over gestation. These declines are consistent in individuals forT 2 * $$ {\mathrm{T}}_2^{\ast } $$ (covariance = -0.47), but not ADC (covariance = -1.04). TheT 2 * IVIM $$ {\mathrm{T}}_2^{\ast}\;\mathrm{IVIM} $$ model identified a consistent decline in individuals over gestation inT 2 * $$ {\mathrm{T}}_2^{\ast } $$ 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 placentalT 2 * $$ {\mathrm{T}}_2^{\ast } $$ and ADC values decrease over gestation, although onlyT 2 * $$ {\mathrm{T}}_2^{\ast } $$ values showed consistent trends within subjects. There was minimal individual variation in rates of change ofT 2 * $$ {\mathrm{T}}_2^{\ast } $$ 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 bicompartmentalT 2 * IVIM $$ {\mathrm{T}}_2^{\ast}\;\mathrm{IVIM} $$ 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.
Collapse
Affiliation(s)
- Daniel Cromb
- Centre for the Developing Brain, School of Biomedical Engineering and Imaging SciencesKing's College LondonLondonUK
| | - Paddy J. Slator
- Centre for Medical Image Computing, Department of Computer ScienceUniversity College LondonLondonUK
| | - Miguel De La Fuente
- Centre for the Developing Brain, School of Biomedical Engineering and Imaging SciencesKing's College LondonLondonUK
| | - Anthony N. Price
- Centre for the Developing Brain, School of Biomedical Engineering and Imaging SciencesKing's College LondonLondonUK
- Centre for Medical EngineeringSchool of Biomedical Engineering and Imaging Sciences, King's College LondonLondonUK
| | - Mary Rutherford
- Centre for the Developing Brain, School of Biomedical Engineering and Imaging SciencesKing's College LondonLondonUK
- MRC Centre for Neurodevelopmental DisordersKing's College LondonLondonUK
| | - Alexia Egloff
- Centre for the Developing Brain, School of Biomedical Engineering and Imaging SciencesKing's College LondonLondonUK
| | - Serena J. Counsell
- Centre for the Developing Brain, School of Biomedical Engineering and Imaging SciencesKing's College LondonLondonUK
| | - Jana Hutter
- Centre for the Developing Brain, School of Biomedical Engineering and Imaging SciencesKing's College LondonLondonUK
- Centre for Medical EngineeringSchool of Biomedical Engineering and Imaging Sciences, King's College LondonLondonUK
| |
Collapse
|
7
|
Biondetti E, Cho J, Lee H. Cerebral oxygen metabolism from MRI susceptibility. Neuroimage 2023; 276:120189. [PMID: 37230206 PMCID: PMC10335841 DOI: 10.1016/j.neuroimage.2023.120189] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 04/26/2023] [Accepted: 05/23/2023] [Indexed: 05/27/2023] Open
Abstract
This article provides an overview of MRI methods exploiting magnetic susceptibility properties of blood to assess cerebral oxygen metabolism, including the tissue oxygen extraction fraction (OEF) and the cerebral metabolic rate of oxygen (CMRO2). The first section is devoted to describing blood magnetic susceptibility and its effect on the MRI signal. Blood circulating in the vasculature can have diamagnetic (oxyhemoglobin) or paramagnetic properties (deoxyhemoglobin). The overall balance between oxygenated and deoxygenated hemoglobin determines the induced magnetic field which, in turn, modulates the transverse relaxation decay of the MRI signal via additional phase accumulation. The following sections of this review then illustrate the principles underpinning susceptibility-based techniques for quantifying OEF and CMRO2. Here, it is detailed whether these techniques provide global (OxFlow) or local (Quantitative Susceptibility Mapping - QSM, calibrated BOLD - cBOLD, quantitative BOLD - qBOLD, QSM+qBOLD) measurements of OEF or CMRO2, and what signal components (magnitude or phase) and tissue pools they consider (intravascular or extravascular). Validations studies and potential limitations of each method are also described. The latter include (but are not limited to) challenges in the experimental setup, the accuracy of signal modeling, and assumptions on the measured signal. The last section outlines the clinical uses of these techniques in healthy aging and neurodegenerative diseases and contextualizes these reports relative to results from gold-standard PET.
Collapse
Affiliation(s)
- Emma Biondetti
- Department of Neuroscience, Imaging and Clinical Sciences, "D'Annunzio University" of Chieti-Pescara, Chieti, Italy; Institute for Advanced Biomedical Technologies, "D'Annunzio University" of Chieti-Pescara, Chieti, Italy
| | - Junghun Cho
- Department of Biomedical Engineering, University at Buffalo, The State University of New York, New York, USA
| | - Hyunyeol Lee
- School of Electronic and Electrical Engineering, Kyungpook National University, Daegu, Republic of Korea; Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
| |
Collapse
|
8
|
Improving Development of Drug Treatments for Pregnant Women and the Fetus. Ther Innov Regul Sci 2022; 56:976-990. [PMID: 35881237 PMCID: PMC9315086 DOI: 10.1007/s43441-022-00433-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 06/30/2022] [Indexed: 12/12/2022]
Abstract
The exclusion of pregnant populations, women of reproductive age, and the fetus from clinical trials of therapeutics is a major global public health issue. It is also a problem of inequity in medicines development, as pregnancy is a protected characteristic. The current regulatory requirements for drugs in pregnancy are being analyzed by a number of agencies worldwide. There has been considerable investment in developing expertise in pregnancy clinical trials (for the pregnant person and the fetus) such as the Obstetric-Fetal Pharmacology Research Centers funded by the National Institute of Child Health and Human Development. Progress has also been made in how to define and grade clinical trial safety in pregnant women, the fetus, and neonate. Innovative methods to model human pregnancy physiology and pharmacology using computer simulations are also gaining interest. Novel ways to assess fetal well-being and placental function using magnetic resonance imaging, computerized cardiotocography, serum circulating fetoplacental proteins, and mRNA may permit better assessment of the safety and efficacy of interventions in the mother and fetus. The core outcomes in women’s and newborn health initiative is facilitating the consistent reporting of data from pregnancy trials. Electronic medical records integrated with pharmacy services should improve the strength of pharmacoepidemiologic and pharmacovigilance studies. Incentives such as investigational plans and orphan disease designation have been taken up for obstetric, fetal, and neonatal diseases. This review describes the progress that is being made to better understand the extent of the problem and to develop applicable solutions.
Collapse
|
9
|
Abulnaga SM, Turk EA, Bessmeltsev M, Grant PE, Solomon J, Golland P. Volumetric Parameterization of the Placenta to a Flattened Template. IEEE TRANSACTIONS ON MEDICAL IMAGING 2022; 41:925-936. [PMID: 34784274 PMCID: PMC9069541 DOI: 10.1109/tmi.2021.3128743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
We present a volumetric mesh-based algorithm for parameterizing the placenta to a flattened template to enable effective visualization of local anatomy and function. MRI shows potential as a research tool as it provides signals directly related to placental function. However, due to the curved and highly variable in vivo shape of the placenta, interpreting and visualizing these images is difficult. We address interpretation challenges by mapping the placenta so that it resembles the familiar ex vivo shape. We formulate the parameterization as an optimization problem for mapping the placental shape represented by a volumetric mesh to a flattened template. We employ the symmetric Dirichlet energy to control local distortion throughout the volume. Local injectivity in the mapping is enforced by a constrained line search during the gradient descent optimization. We validate our method using a research study of 111 placental shapes extracted from BOLD MRI images. Our mapping achieves sub-voxel accuracy in matching the template while maintaining low distortion throughout the volume. We demonstrate how the resulting flattening of the placenta improves visualization of anatomy and function. Our code is freely available at https://github.com/mabulnaga/placenta-flattening.
Collapse
|
10
|
Garbow JR, Neil JJ. Editorial on "Ex vivo MRI of the Normal Human Placenta: Structural-Functional Interplay and the Association With Birth Weight". J Magn Reson Imaging 2021; 56:145-146. [PMID: 34873770 DOI: 10.1002/jmri.28020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 11/26/2021] [Indexed: 11/07/2022] Open
Affiliation(s)
- Joel R Garbow
- Department of Radiology, St. Louis, Missouri, USA.,The Alvin J Siteman Cancer Center, St. Louis, Missouri, USA
| | - Jeffrey J Neil
- Department of Radiology, St. Louis, Missouri, USA.,Department of Neurology, St. Louis, Missouri, USA
| |
Collapse
|
11
|
Stout JN, Bedoya MA, Grant PE, Estroff JA. Fetal Neuroimaging Updates. Magn Reson Imaging Clin N Am 2021; 29:557-581. [PMID: 34717845 PMCID: PMC8562558 DOI: 10.1016/j.mric.2021.06.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
MR imaging is used in conjunction with ultrasound screening for fetal brain abnormalities because it offers better contrast, higher resolution, and has multiplanar capabilities that increase the accuracy and confidence of diagnosis. Fetal motion still severely limits the MR imaging sequences that can be acquired. We outline the current acquisition strategies for fetal brain MR imaging and discuss the near term advances that will improve its reliability. Prospective and retrospective motion correction aim to make the complement of MR neuroimaging modalities available for fetal diagnosis, improve the performance of existing modalities, and open new horizons to understanding in utero brain development.
Collapse
Affiliation(s)
- Jeffrey N Stout
- Fetal and Neonatal Neuroimaging and Developmental Science Center, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA.
| | - M Alejandra Bedoya
- Department of Radiology, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA
| | - P Ellen Grant
- Fetal and Neonatal Neuroimaging and Developmental Science Center, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA; Department of Radiology, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA; Department of Pediatrics, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Judy A Estroff
- Department of Radiology, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA; Maternal Fetal Care Center, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA
| |
Collapse
|
12
|
Damhuis SE, Ganzevoort W, Gordijn SJ. Abnormal Fetal Growth: Small for Gestational Age, Fetal Growth Restriction, Large for Gestational Age: Definitions and Epidemiology. Obstet Gynecol Clin North Am 2021; 48:267-279. [PMID: 33972065 DOI: 10.1016/j.ogc.2021.02.002] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Abnormal fetal growth (growth restriction and overgrowth) is associated with perinatal morbidity, mortality, and lifelong risks to health. To describe abnormal growth, "small for gestational age" and "large for gestational age" are commonly used terms. However, both are statistical definitions of fetal size below or above a certain threshold related to a reference population, rather than referring to an abnormal condition. Fetuses can be constitutionally small or large and thus healthy, whereas fetuses with seemingly normal size can be growth restricted or overgrown. Although golden standards to detect abnormal growth are lacking, understanding of both pathologic conditions has improved significantly.
Collapse
Affiliation(s)
- Stefanie E Damhuis
- Department of Obstetrics and Gynaecology, University Medical Center of Groningen, CB20, Hanzeplein 1, 9700RB Groningen, the Netherlands; Department of Obstetrics and Gynaecology, University Medical Centers Amsterdam, University of Amsterdam, H4, PO Box 22660, Amsterdam 1105 AZ, the Netherlands.
| | - Wessel Ganzevoort
- Department of Obstetrics and Gynaecology, University Medical Centers Amsterdam, University of Amsterdam, H4, PO Box 22660, Amsterdam 1105 AZ, the Netherlands
| | - Sanne J Gordijn
- Department of Obstetrics and Gynaecology, University Medical Center of Groningen, CB20, Hanzeplein 1, 9700RB Groningen, the Netherlands
| |
Collapse
|
13
|
Lewis RM, Pearson-Farr JE. Multiscale three-dimensional imaging of the placenta. Placenta 2020; 102:55-60. [DOI: 10.1016/j.placenta.2020.01.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 01/30/2020] [Accepted: 01/31/2020] [Indexed: 01/18/2023]
|
14
|
Real-time Assessment of the Development and Function of the Placenta Across Gestation to Support Therapeutics in Pregnancy. Clin Ther 2020; 43:279-286. [PMID: 33246660 DOI: 10.1016/j.clinthera.2020.11.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 11/02/2020] [Accepted: 11/02/2020] [Indexed: 12/19/2022]
Abstract
The placenta is vital to the health and development of the fetus, serving to deliver oxygen and nutrients, facilitate the removal of waste products, and provide a barrier to pathogens and other harmful substances present in the maternal circulation. When these processes fail to operate normally, they can lead to complications of pregnancy such as preeclampsia or fetal growth restriction. The development of novel therapeutics for the mother, fetus, or placenta requires a mechanistic understanding of the development and functions of the placenta. For the obstetric clinician, being able to monitor the placenta throughout the pregnancy and to measure the impact of any treatment modality on the mother and the developing fetus are essential for providing the best possible care. The Eunice Kennedy Shriver National Institute of Child Health and Human Development at the National Institutes of Health has been a longtime supporter of research on the placenta. In 2014, the Human Placenta Project was initiated to help to drive an understanding of the biology of the human placenta and to facilitate the development of novel tools and approaches to allow for safe, noninvasive, real-time assessment of the placenta across pregnancy. Those efforts, along with others from around the globe, are showing promise. Although not yet ready for clinical application, these advances are moving the field forward and are certain to have a tremendous impact on the development and assessment of therapeutics designed for treating conditions of pregnancy.
Collapse
|
15
|
Stout JN, Rouhani S, Turk EA, Ha CG, Luo J, Rich K, Wald LL, Adalsteinsson E, Barth WH, Grant PE, Roberts DJ. Placental MRI: Development of an MRI compatible ex vivo system for whole placenta dual perfusion. Placenta 2020; 101:4-12. [PMID: 32905974 DOI: 10.1016/j.placenta.2020.07.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 07/24/2020] [Indexed: 10/23/2022]
Abstract
PURPOSE Placental dysfunction plays a key role in diseases that affect the fetus in utero and after birth. Aiming to develop a platform for validating in vivo placental MRI and investigations into placental physiology, we designed and built a prototype MRI-compatible perfusion chamber with an integrated MRI receive coil for high SNR ex vivo placental imaging. PRINCIPAL RESULTS After optimizing placenta vascular clearing and perfusion protocols, we performed contrast enhanced MR angiography and MR relaxometry on eight carefully selected placentas while they were perfused via the umbilical arteries (UAs). Additionally, two of these placentas underwent maternal perfusion via the intervillous space (IVS). Despite striving for homogenous perfusion across the whole placenta, imaging results were highly heterogeneous for both UA and IVS perfused placentas. By histology, we observed blood congestion in the villi in regions that showed low UA perfusion during MRI. In two placentas prominent chorionic arteries followed by adjacent veins underwent contrast enhancement in the absence of villous capillary blush. The single placenta from a pregnancy affected by IUGR had the most homogeneous villous capillary perfusion. MAJOR CONCLUSIONS A dual perfusion system for ex vivo placentas compatible with MRI permitted assessment of UA and IVS placental perfusion. We observed spatial UA perfusion heterogeneity and evidence for arteriovenous shunting in placentas from normal pregnancies and deliveries, but relative villous capillary perfusion homogeneity in a single IUGR placenta. Future work will focus on system optimization, followed by physiological manipulation and validation of in vivo placental MRI.
Collapse
Affiliation(s)
- Jeffrey N Stout
- Fetal-Neonatal Neuroimaging & Developmental Sciences Center, Boston Children's Hospital, Boston, MA, USA.
| | - Shahin Rouhani
- Fetal-Neonatal Neuroimaging & Developmental Sciences Center, Boston Children's Hospital, Boston, MA, USA; Department of Pathology, Massachusetts General Hospital, Boston, MA, USA
| | - Esra Abaci Turk
- Fetal-Neonatal Neuroimaging & Developmental Sciences Center, Boston Children's Hospital, Boston, MA, USA
| | - Christopher G Ha
- Fetal-Neonatal Neuroimaging & Developmental Sciences Center, Boston Children's Hospital, Boston, MA, USA
| | - Jie Luo
- Fetal-Neonatal Neuroimaging & Developmental Sciences Center, Boston Children's Hospital, Boston, MA, USA
| | - Karen Rich
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
| | - Lawerence L Wald
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
| | - Elfar Adalsteinsson
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA; Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - William H Barth
- Maternal-Fetal Medicine, Obstetrics and Gynecology, Massachusetts General Hospital, Boston, MA, USA
| | - P Ellen Grant
- Fetal-Neonatal Neuroimaging & Developmental Sciences Center, Boston Children's Hospital, Boston, MA, USA
| | - Drucilla J Roberts
- Department of Pathology, Massachusetts General Hospital, Boston, MA, USA
| |
Collapse
|
16
|
Abaci Turk E, Abulnaga SM, Luo J, Stout JN, Feldman HA, Turk A, Gagoski B, Wald LL, Adalsteinsson E, Roberts DJ, Bibbo C, Robinson JN, Golland P, Grant PE, Barth WH. Placental MRI: Effect of maternal position and uterine contractions on placental BOLD MRI measurements. Placenta 2020; 95:69-77. [PMID: 32452404 DOI: 10.1016/j.placenta.2020.04.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 04/16/2020] [Accepted: 04/17/2020] [Indexed: 12/24/2022]
Abstract
INTRODUCTION Before using blood-oxygen-level-dependent magnetic resonance imaging (BOLD MRI) during maternal hyperoxia as a method to detect individual placental dysfunction, it is necessary to understand spatiotemporal variations that represent normal placental function. We investigated the effect of maternal position and Braxton-Hicks contractions on estimates obtained from BOLD MRI of the placenta during maternal hyperoxia. METHODS For 24 uncomplicated singleton pregnancies (gestational age 27-36 weeks), two separate BOLD MRI datasets were acquired, one in the supine and one in the left lateral maternal position. The maternal oxygenation was adjusted as 5 min of room air (21% O2), followed by 5 min of 100% FiO2. After datasets were corrected for signal non-uniformities and motion, global and regional BOLD signal changes in R2* and voxel-wise Time-To-Plateau (TTP) in the placenta were measured. The overall placental and uterine volume changes were determined across time to detect contractions. RESULTS In mothers without contractions, increases in global placental R2* in the supine position were larger compared to the left lateral position with maternal hyperoxia. Maternal position did not alter global TTP but did result in regional changes in TTP. 57% of the subjects had Braxton-Hicks contractions and 58% of these had global placental R2* decreases during the contraction. CONCLUSION Both maternal position and Braxton-Hicks contractions significantly affect global and regional changes in placental R2* and regional TTP. This suggests that both factors must be taken into account in analyses when comparing placental BOLD signals over time within and between individuals.
Collapse
Affiliation(s)
- Esra Abaci Turk
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
| | - S Mazdak Abulnaga
- Computer Science and Artificial Intelligence Laboratory (CSAIL), Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Jie Luo
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA; School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Jeffrey N Stout
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Henry A Feldman
- Institutional Centers for Clinical and Translational Research, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Ata Turk
- Electrical Computer Engineering Department, Boston University, Boston, MA, USA
| | - Borjan Gagoski
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Lawrence L Wald
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA; Radiology, Harvard Medical School, Boston, MA, United States; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States
| | - Elfar Adalsteinsson
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA; Harvard-MIT Health Sciences and Technology; Massachusetts Institute of Technology, Cambridge, MA, USA; Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Drucilla J Roberts
- Department of Pathology, Massachusetts General Hospital, Boston, MA, USA
| | - Carolina Bibbo
- Maternal Fetal Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - Julian N Robinson
- Maternal Fetal Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - Polina Golland
- Computer Science and Artificial Intelligence Laboratory (CSAIL), Massachusetts Institute of Technology, Cambridge, MA, USA; Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - P Ellen Grant
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - William H Barth
- Maternal-Fetal Medicine, Obstetrics and Gynecology, Massachusetts General Hospital, Boston, MA, USA
| |
Collapse
|