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Yin Y, Clark AR, Collins SL. 3D Single Vessel Fractional Moving Blood Volume (3D-svFMBV): Fully Automated Tissue Perfusion Estimation Using Ultrasound. IEEE TRANSACTIONS ON MEDICAL IMAGING 2024; 43:2707-2717. [PMID: 38478454 DOI: 10.1109/tmi.2024.3376668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
Power Doppler ultrasound (PD-US) is the ideal modality to assess tissue perfusion as it is cheap, patient-friendly and does not require ionizing radiation. However, meaningful inter-patient comparison only occurs if differences in tissue-attenuation are corrected for. This can be done by standardizing the PD-US signal to a blood vessel assumed to have 100% vascularity. The original method to do this is called fractional moving blood volume (FMBV). We describe a novel, fully-automated method combining image processing, numerical modelling, and deep learning to estimate three-dimensional single vessel fractional moving blood volume (3D-svFMBV). We map the PD signals to a characteristic intensity profile within a single large vessel to define the standardization value at the high shear vessel margins. This removes the need for mathematical correction for background signal which can introduce error. The 3D-svFMBV was first tested on synthetic images generated using the characteristics of uterine artery and physiological ultrasound noise levels, demonstrating prediction of standardization value close to the theoretical ideal. Clinical utility was explored using 143 first-trimester placental ultrasound volumes. More biologically plausible perfusion estimates were obtained, showing improved prediction of pre-eclampsia compared with those generated with the semi-automated original 3D-FMBV technique. The proposed 3D-svFMBV method overcomes the limitations of the original technique to provide accurate and robust placental perfusion estimation. This not only has the potential to provide an early pregnancy screening tool but may also be used to assess perfusion of different organs and tumors.
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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 PMCID: PMC11257151 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.
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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
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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.
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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
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de Vos ES, Koning AHJ, Steegers-Theunissen RPM, Willemsen SP, van Rijn BB, Steegers EAP, Mulders AGMGJ. Assessment of first-trimester utero-placental vascular morphology by 3D power Doppler ultrasound image analysis using a skeletonization algorithm: the Rotterdam Periconception Cohort. Hum Reprod 2022; 37:2532-2545. [PMID: 36125007 PMCID: PMC9627684 DOI: 10.1093/humrep/deac202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 08/16/2022] [Indexed: 11/22/2022] Open
Abstract
STUDY QUESTION Can three-dimensional (3D) Power Doppler (PD) ultrasound and a skeletonization algorithm be used to assess first-trimester development of the utero-placental vascular morphology? SUMMARY ANSWER The application of 3D PD ultrasonography and a skeletonization algorithm facilitates morphologic assessment of utero-placental vascular development in the first trimester and reveals less advanced vascular morphologic development in pregnancies with placenta-related complications than in pregnancies without placenta-related complications. WHAT IS KNOWN ALREADY Suboptimal development of the utero-placental vasculature is one of the main contributors to the periconceptional origin of placenta-related complications. The nature and attribution of aberrant vascular structure and branching patterns remain unclear, as validated markers monitoring first-trimester utero-placental vascular morphologic development are lacking. STUDY DESIGN, SIZE, DURATION In this prospective observational cohort, 214 ongoing pregnancies were included before 10 weeks gestational age (GA) at a tertiary hospital between January 2017 and July 2018, as a subcohort of the ongoing Rotterdam Periconception Cohort study. PARTICIPANTS/MATERIALS, SETTING, METHODS By combining 3D PD ultrasonography and virtual reality, utero-placental vascular volume (uPVV) measurements were obtained at 7, 9 and 11 weeks GA. A skeletonization algorithm was applied to the uPVV measurements to generate the utero-placental vascular skeleton (uPVS), a network-like structure containing morphologic characteristics of the vasculature. Quantification of vascular morphology was performed by assigning a morphologic characteristic to each voxel in the uPVS (end-, vessel-, bifurcation- or crossing-point) and calculating total vascular network length. A Mann–Whitney U test was performed to investigate differences in morphologic development of the first-trimester utero-placental vasculature between pregnancies with and without placenta-related complications. Linear mixed models were used to estimate trajectories of the morphologic characteristics in the first trimester. MAIN RESULTS AND THE ROLE OF CHANCE All morphologic characteristics of the utero-placental vasculature increased significantly in the first trimester (P < 0.005). In pregnancies with placenta-related complications (n = 54), utero-placental vascular branching was significantly less advanced at 9 weeks GA (vessel points P = 0.040, bifurcation points P = 0.050, crossing points P = 0.020, total network length P = 0.023). Morphologic growth trajectories remained similar after adjustment for parity, conception mode, foetal sex and occurrence of placenta-related complications. LIMITATIONS, REASONS FOR CAUTION The tertiary setting of this prospective observational study provides high internal, but possibly limited external, validity. Extrapolation of the study’s findings should therefore be addressed with caution. WIDER IMPLICATIONS OF THE FINDINGS The uPVS enables assessment of morphologic development of the first-trimester utero-placental vasculature. Further investigation of this innovative methodology needs to determine its added value for the assessment of (patho-) physiological utero-placental vascular development. STUDY FUNDING/COMPETING INTEREST(S) This research was funded by the Department of Obstetrics and Gynecology of the Erasmus MC, University Medical Centre, Rotterdam, The Netherlands. There are no conflicts of interest. TRIAL REGISTRATION NUMBER Registered at the Dutch Trial Register (NTR6854).
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Affiliation(s)
- Eline S de Vos
- Department of Obstetrics and Gynecology, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, The Netherlands
| | - Anton H J Koning
- Department of Pathology, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, The Netherlands
| | | | - Sten P Willemsen
- Department of Obstetrics and Gynecology, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, The Netherlands.,Department of Biostatistics, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, The Netherlands
| | - Bas B van Rijn
- Department of Obstetrics and Gynecology, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, The Netherlands
| | - Eric A P Steegers
- Department of Obstetrics and Gynecology, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, The Netherlands
| | - Annemarie G M G J Mulders
- Department of Obstetrics and Gynecology, Erasmus MC, University Medical Centre Rotterdam, Rotterdam, The Netherlands
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Hernandez-Andrade E, Huntley ES, Bartal MF, Soto-Torres EE, Tirosh D, Jaiman S, Johnson A. Doppler evaluation of normal and abnormal placenta. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2022; 60:28-41. [PMID: 34806234 DOI: 10.1002/uog.24816] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 11/12/2021] [Indexed: 06/13/2023]
Abstract
Doppler techniques are needed for the evaluation of the intraplacental circulation and can be of great value in the diagnosis of placental anomalies. Highly sensitive Doppler techniques can differentiate between the maternal (spiral arteries) and fetal (intraplacental branches of the umbilical artery) components of the placental circulation and assist in the evaluation of the placental functional units. A reduced number of placental functional units can be associated with obstetric complications, such as fetal growth restriction. Doppler techniques can also provide information on decidual vessels and blood movement. Abnormal decidual circulation increases the risk of placenta accreta. Doppler evaluation of the placenta greatly contributes to the diagnosis and clinical management of placenta accreta, vasa previa, placental infarcts, placental infarction hematoma, maternal floor infarction, massive perivillous fibrin deposition and placental tumors. However, it has a limited role in the diagnosis and clinical management of placental abruption, placental hematomas, placental mesenchymal dysplasia and mapping of placental anastomoses in monochorionic twin pregnancies. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.
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Affiliation(s)
- E Hernandez-Andrade
- Department of Obstetrics and Gynecology and Reproductive Sciences, McGovern Medical School, University of Texas, Health Science Center at Houston (UTHealth), Houston, TX, USA
| | - E S Huntley
- Department of Obstetrics and Gynecology and Reproductive Sciences, McGovern Medical School, University of Texas, Health Science Center at Houston (UTHealth), Houston, TX, USA
| | - M F Bartal
- Department of Obstetrics and Gynecology and Reproductive Sciences, McGovern Medical School, University of Texas, Health Science Center at Houston (UTHealth), Houston, TX, USA
| | - E E Soto-Torres
- Department of Obstetrics and Gynecology and Reproductive Sciences, McGovern Medical School, University of Texas, Health Science Center at Houston (UTHealth), Houston, TX, USA
| | - D Tirosh
- Department of Obstetrics and Gynecology, Soroka University Medical Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - S Jaiman
- Department of Obstetrics and Gynecology Wayne State University, Detroit, MI, USA
| | - A Johnson
- Department of Obstetrics and Gynecology and Reproductive Sciences, McGovern Medical School, University of Texas, Health Science Center at Houston (UTHealth), Houston, TX, USA
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Issa E, Stevenson GN, Gomes De Melo Tavares Ferreira AE, Chang MHY, Alphonse J, Welsh AW. The Influence of Hyperoxygenation on Fetal Brain Vascularity Measured Using 3D Power Doppler Ultrasound and the Index "Fractional Moving Blood Volume". Fetal Diagn Ther 2021; 48:651-659. [PMID: 34710879 DOI: 10.1159/000517727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Accepted: 06/08/2021] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Maternal hyperoxygenation effects on fetal cerebral hemodynamics are largely unknown. This study aimed to determine efficacy and reliability of a validated power Doppler ultrasound (US) index, fractional moving blood volume (FMBV), at measuring fetal cerebral vasculature changes during maternal hyperoxia. METHODS The fetal cerebral effects of 10 min of hyperoxygenation at 2 flow rates (52%/60% FiO2) were evaluated in women in their third trimester of pregnancy. 2D-US and 3D-US in a transverse plane were performed before, during, and following maternal hyperoxygenation with FMBV estimation performed offline. RESULTS Forty-five cases provided data for analysis. Mean intraobserver ICCs were 0.89 (3D-FMBV) and 0.84 (2D-FMBV). A significant difference in vascularity before and during and before and after 60% hyperoxia was observed (p < 0.05), whereas no significant differences were found at 52% hyperoxia (p > 0.05). Significant differences in vascularity were found between 2D-FMBV and 3D-FMBV (p < 0.01). CONCLUSION Measurement of fetal cerebral vascularity by 3D-FMBV and 2D-FMBV was highly reproducible. The differing cerebral vascular changes seen with 60% but not 52% FiO2 suggest a possible "threshold effect" that may have influenced prior studies. Further studies are needed to assess cerebral effects of maternal hyperoxygenation on compromised fetuses.
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Affiliation(s)
- Evitta Issa
- School of Women's and Children's Health, Faculty of Medicine, University of New South Wales Sydney, Sydney, New South Wales, Australia
| | - Gordon Niall Stevenson
- School of Women's and Children's Health, Faculty of Medicine, University of New South Wales Sydney, Sydney, New South Wales, Australia
| | | | - Melissa Han Yiin Chang
- School of Women's and Children's Health, Faculty of Medicine, University of New South Wales Sydney, Sydney, New South Wales, Australia
| | - Jennifer Alphonse
- School of Women's and Children's Health, Faculty of Medicine, University of New South Wales Sydney, Sydney, New South Wales, Australia
| | - Alec William Welsh
- School of Women's and Children's Health, Faculty of Medicine, University of New South Wales Sydney, Sydney, New South Wales, Australia.,Department of Maternal-Fetal Medicine, Royal Hospital for Women, Randwick, New South Wales, Australia
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Bertholdt C, Dap M, Beaumont M, Duan J, Morel O. New insights into human functional ultrasound imaging. Placenta 2021; 117:5-12. [PMID: 34768169 DOI: 10.1016/j.placenta.2021.10.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 08/23/2021] [Accepted: 10/06/2021] [Indexed: 12/17/2022]
Abstract
Ultrasound imaging is a vital tool for exploring in vivo the placental function which is essential to understand pathological phenomena such as preeclampsia or intrauterine growth restriction. As technology advances including ready availability of three-dimensional (3D) probes and novel software, new markers of placental function become possible. The objective of this review was to provide an overview of the new ultrasound markers of placental function with a focus on the potential clinical application of three-dimensional power Doppler (3DPD). A broad-free text literature search was undertaken based on human placental studies and sixty full-text studies were included in this review. Three-dimensional power Doppler is a promising technique to predict preeclampsia in the first trimester. However, the influence of external factors such as body mass index, parameter standardisation and machine settings still need to be addressed. Contrast-enhanced ultrasound is currently reserved for research, because the required injected contrast mediums are not currently approved for use in pregnancy, although the safety data is reassuring.
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Affiliation(s)
- C Bertholdt
- Université de Lorraine, CHRU-Nancy, Pôle de Gynécologie-Obstétrique, F-54000 Nancy, France; Université de Lorraine, Inserm, IADI, F-54000 Nancy, France.
| | - M Dap
- Université de Lorraine, CHRU-Nancy, Pôle de Gynécologie-Obstétrique, F-54000 Nancy, France
| | - M Beaumont
- CHRU-Nancy, Inserm, Université de Lorraine, CIC, Innovation Technologique, F-54000 Nancy, France
| | - J Duan
- Hubei Clinical Research Center for Prenatal Diagnosis and Birth Health, Hubei, 430071, China; Gynecology and Obstetrical Service, Zhongnan Hospital of Wuhan University, Hubei, 430071, China
| | - O Morel
- Université de Lorraine, CHRU-Nancy, Pôle de Gynécologie-Obstétrique, F-54000 Nancy, France; Université de Lorraine, Inserm, IADI, F-54000 Nancy, France
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A 10-Year Retrospective Review of Prenatal Applications, Current Challenges and Future Prospects of Three-Dimensional Sonoangiography. Diagnostics (Basel) 2021; 11:diagnostics11081511. [PMID: 34441444 PMCID: PMC8394388 DOI: 10.3390/diagnostics11081511] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Revised: 08/14/2021] [Accepted: 08/18/2021] [Indexed: 12/12/2022] Open
Abstract
Realistic reconstruction of angioarchitecture within the morphological landmark with three-dimensional sonoangiography (three-dimensional power Doppler; 3D PD) may augment standard prenatal ultrasound and Doppler assessments. This study aimed to (a) present a technical overview, (b) determine additional advantages, (c) identify current challenges, and (d) predict trajectories of 3D PD for prenatal assessments. PubMed and Scopus databases for the last decade were searched. Although 307 publications addressed our objectives, their heterogeneity was too broad for statistical analyses. Important findings are therefore presented in descriptive format and supplemented with the authors’ 3D PD images. Acquisition, analysis, and display techniques need to be personalized to improve the quality of flow-volume data. While 3D PD indices of the first-trimester placenta may improve the prediction of preeclampsia, research is needed to standardize the measurement protocol. In highly experienced hands, the unique 3D PD findings improve the diagnostic accuracy of placenta accreta spectrum. A lack of quality assurance is the central challenge to incorporating 3D PD in prenatal care. Machine learning may broaden clinical translations of prenatal 3D PD. Due to its operator dependency, 3D PD has low reproducibility. Until standardization and quality assurance protocols are established, its use as a stand-alone clinical or research tool cannot be recommended.
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Looney P, Yin Y, Collins SL, Nicolaides KH, Plasencia W, Molloholli M, Natsis S, Stevenson GN. Fully Automated 3-D Ultrasound Segmentation of the Placenta, Amniotic Fluid, and Fetus for Early Pregnancy Assessment. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2021; 68:2038-2047. [PMID: 33460372 PMCID: PMC8154733 DOI: 10.1109/tuffc.2021.3052143] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Volumetric placental measurement using 3-D ultrasound has proven clinical utility in predicting adverse pregnancy outcomes. However, this metric cannot currently be employed as part of a screening test due to a lack of robust and real-time segmentation tools. We present a multiclass (MC) convolutional neural network (CNN) developed to segment the placenta, amniotic fluid, and fetus. The ground-truth data set consisted of 2093 labeled placental volumes augmented by 300 volumes with placenta, amniotic fluid, and fetus annotated. A two-pathway, hybrid (HB) model using transfer learning, a modified loss function, and exponential average weighting was developed and demonstrated the best performance for placental segmentation (PS), achieving a Dice similarity coefficient (DSC) of 0.84- and 0.38-mm average Hausdorff distances (HDAV). The use of a dual-pathway architecture improved the PS by 0.03 DSC and reduced HDAV by 0.27 mm compared with a naïve MC model. The incorporation of exponential weighting produced a further small improvement in DSC by 0.01 and a reduction of HDAV by 0.44 mm. Per volume inference using the FCNN took 7-8 s. This method should enable clinically relevant morphometric measurements (such as volume and total surface area) to be automatically generated for the placenta, amniotic fluid, and fetus. The ready availability of such metrics makes a population-based screening test for adverse pregnancy outcomes possible.
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Clark AR, Lee TC, James JL. Computational modeling of the interactions between the maternal and fetal circulations in human pregnancy. WIREs Mech Dis 2020; 13:e1502. [PMID: 32744412 DOI: 10.1002/wsbm.1502] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 06/16/2020] [Accepted: 06/17/2020] [Indexed: 12/14/2022]
Abstract
In pregnancy, fetal growth is supported by its placenta. In turn, the placenta is nourished by maternal blood, delivered from the uterus, in which the vasculature is dramatically transformed to deliver this blood an ever increasing volume throughout gestation. A healthy pregnancy is thus dependent on the development of both the placental and maternal circulations, but also the interface where these physically separate circulations come in close proximity to exchange gases and nutrients between mum and baby. As the system continually evolves during pregnancy, our understanding of normal vascular anatomy, and how this impacts placental exchange function is limited. Understanding this is key to improve our ability to understand, predict, and detect pregnancy pathologies, but presents a number of challenges, due to the inaccessibility of the pregnant uterus to invasive measurements, and limitations in the resolution of imaging modalities safe for use in pregnancy. Computational approaches provide an opportunity to gain new insights into normal and abnormal pregnancy, by connecting observed anatomical changes from high-resolution imaging to function, and providing metrics that can be observed by routine clinical ultrasound. Such advanced modeling brings with it challenges to scale detailed anatomical models to reflect organ level function. This suggests pathways for future research to provide models that provide both physiological insights into pregnancy health, but also are simple enough to guide clinical focus. We the review evolution of computational approaches to understanding the physiology and pathophysiology of pregnancy in the uterus, placenta, and beyond focusing on both opportunities and challenges. This article is categorized under: Reproductive System Diseases >Computational Models.
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Affiliation(s)
- Alys R Clark
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Tet Chuan Lee
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Joanna L James
- Department of Obstetrics and Gynaecology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
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Cheung W, Stevenson GN, de Melo Tavares Ferreira AEG, Alphonse J, Welsh AW. Feasibility of image registration and fusion for evaluation of structure and perfusion of the entire second trimester placenta by three-dimensional power Doppler ultrasound. Placenta 2020; 94:13-19. [PMID: 32217266 DOI: 10.1016/j.placenta.2020.03.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 02/24/2020] [Accepted: 03/10/2020] [Indexed: 11/17/2022]
Abstract
BACKGROUND Placental perfusion can be evaluated by 3D power Doppler ultrasound (3D PD-US), particularly using the validated tool 3D Fractional Moving Blood Volume (3D-FMBV); however regional variability and size limitations beyond the first trimester mean that multiple 3D PD-US volumes are required to evaluate the whole organ. PURPOSE We assessed the feasibility of manual offline stitching of second trimester 3D PD-US volumes of the placenta to assess whole organ perfusion using 3D-FMBV. MATERIALS AND METHODS This was a single-centre, prospective, observational cohort study of 36 normal second trimester singleton pregnancies with anterior placentas. 3D PD-US placental volumes were manually segmented offline and stitched together by rigid registration using manually selected, pair-wise coordinates. Data acquisition and offline volume segmentation and stitching were triplicated by a single observer with Dice similarity coefficient (DSC) and Hausdorff distance used to assess consistency. Intraclass correlation coefficient (ICC) was used to assess intra-observer repeatability of 3D-FMBV and placental volume. RESULTS Acquisition and stitching success were 94% and 88%, respectively. Median time for acquisition, segmentation and stitching were 13 min, 40 min and 95 min, respectively. Median intra-observer DSCs were 0.94 and 0.88, and Hausdorff distances were 11.85 mm and 36.6 mm, for segmentations and stitching, respectively. CONCLUSION 3D-ultrasound volume stitching of the placenta is technically feasible. Intra-observer repeatability was good to excellent for all measured parameters. This work demonstrates technical feasibility; further studies may provide the basis of an in-vivo assessment tool to measure the placenta in mid-to late pregnancy.
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Affiliation(s)
- Winnie Cheung
- School of Women's and Children's Health, University of New South Wales, Randwick, New South Wales, Australia
| | - Gordon N Stevenson
- School of Women's and Children's Health, University of New South Wales, Randwick, New South Wales, Australia
| | | | - Jennifer Alphonse
- School of Women's and Children's Health, University of New South Wales, Randwick, New South Wales, Australia
| | - Alec W Welsh
- School of Women's and Children's Health, University of New South Wales, Randwick, New South Wales, Australia; Department of Maternal-Fetal Medicine, Royal Hospital for Women, Randwick, New South Wales, Australia.
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Welsh AW, Fowlkes JB, Pinter SZ, Ives KA, Owens GE, Rubin JM, Kripfgans OD, Looney P, Collins SL, Stevenson GN. Three-dimensional US Fractional Moving Blood Volume: Validation of Renal Perfusion Quantification. Radiology 2019; 293:460-468. [PMID: 31573404 PMCID: PMC6800606 DOI: 10.1148/radiol.2019190248] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Background Three-dimensional (3D) fractional moving blood volume (FMBV) derived from 3D power Doppler US has been proposed for noninvasive approximation of perfusion. However, 3D FMBV has never been applied in animals against a ground truth. Purpose To determine the correlation between 3D FMBV and the reference standard of fluorescent microspheres (FMS) for measurement of renal perfusion in a porcine model. Materials and Methods From February 2017 to September 2017, adult pigs were administered FMS before and after measurement of renal 3D FMBV at baseline (100%) and approximately 75%, 50%, and 25% flow levels by using US machines from two different vendors. The 3D power Doppler US volumes were converted and segmented, and correlations between FMS and 3D FMBV were made with simple linear regression (r2). Similarity and reproducibility of manual segmentation were determined with the Dice similarity coefficient and 3D FMBV reproducibility (intraclass correlation coefficient [ICC]). Results Thirteen pigs were studied with 33 flow measurements. Kidney volume (mean Dice similarity coefficient ± standard deviation, 0.89 ± 0.01) and renal segmentation (coefficient of variation = 12.6%; ICC = 0.86) were consistent. The 3D FMBV calculations had high reproducibility (ICC = 0.97; 95% confidence interval: 0.96, 0.98). The 3D FMBV per-pig correlation showed excellent correlation for US machines from both vendors (mean r2 = 0.96 [range, 0.92-1.0] and 0.93 [range, 0.78-1.0], respectively). The correlation between 3D FMBV and perfusion measured with microspheres was high for both US machines (r2 = 0.80 [P < .001] and 0.70 [P < .001], respectively). Conclusion The strong correlation between three-dimensional (3D) fractional moving blood volume (FMBV) and fluorescent microspheres indicates that 3D FMBV shows excellent correlation to perfusion and good reproducibility. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Morrell et al in this issue.
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Affiliation(s)
- Alec W. Welsh
- School of Women’s and Children’s Health, Faculty of Medicine, University of New South Wales, Randwick, New South Wales, Australia
- Department of Maternal-Fetal Medicine, Royal Hospital for Women, Randwick, NSW, Australia
| | - J. Brian Fowlkes
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Stephen Z. Pinter
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Kimberly A Ives
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Gabe E Owens
- Department of Pediatrics, University of Michigan Health System, Ann Arbor, MI, USA
| | - Jonathan M. Rubin
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Oliver D Kripfgans
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Pádraig Looney
- Nuffield Department of Women’s and Reproductive Health, University of Oxford, Oxford, United Kingdom
| | - Sally L. Collins
- Nuffield Department of Women’s and Reproductive Health, University of Oxford, Oxford, United Kingdom
- Fetal Medicine Unit, Women’s Centre, John Radcliffe Hospital, Oxford, United Kingdom
| | - Gordon N. Stevenson
- School of Women’s and Children’s Health, Faculty of Medicine, University of New South Wales, Randwick, New South Wales, Australia
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13
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Mathewlynn S, Collins SL. Volume and vascularity: Using ultrasound to unlock the secrets of the first trimester placenta. Placenta 2019; 84:32-36. [PMID: 31279487 DOI: 10.1016/j.placenta.2019.06.379] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 06/19/2019] [Accepted: 06/22/2019] [Indexed: 11/19/2022]
Abstract
Fetal growth restriction (FGR) is a major cause of perinatal morbidity and mortality. Identifying which pregnancies are at risk of FGR facilitates enhanced surveillance and early delivery before fetal demise can ensue. However, existing risk stratification strategies yield an unacceptably low detection rate. A robust and reliable first trimester screening test for FGR would not only enable high-risk women to be appropriately monitored but would facilitate future trials for possible interventions to enhance fetal growth. Both the volume and vascularity of the first trimester placenta has been demonstrated to be linked to adverse pregnancy outcomes including FGR and pre-eclampsia. The investigation of novel ultrasound markers for FGR are discussed along with the development of methods for fully automatic placental volume estimation which has the potential for use as part of a multi-variable population-based screening test.
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Affiliation(s)
- S Mathewlynn
- Department of Obstetrics and Gynaecology, Milton Keynes University Hospital, Milton Keynes, UK
| | - S L Collins
- Nuffield Department of Women's and Reproductive Health, University of Oxford, UK; Fetal Medicine Unit, The Women's Centre, John Radcliffe Hospital, Oxford, UK.
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14
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Kim YR, Jung I, Park G, Chang SW, Cho HY. First-trimester screening for early preeclampsia risk using maternal characteristics and estimated placental volume. J Matern Fetal Neonatal Med 2019; 34:1155-1160. [PMID: 31220966 DOI: 10.1080/14767058.2019.1628207] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
OBJECTIVE The purpose of this study was to evaluate the strategy of screening for preeclampsia (PE) in the first trimester based on maternal characteristics, and estimated placental volume (EPV). METHODS A prospective cohort study was performed with 351 women enrolled, of which 13 women developed PE. This study analyzed the risk of PE according to ultrasonography findings of the placenta, maternal characteristics, and serum markers. The placental ultrasound exam and maternal serum pregnancy-associated plasma protein A (PAPP-A) was determined at 11+0 to 13+6 weeks and the serum alpha-fetoprotein (MSAFP), human chorionic gonadotropin (hCG), unconjugated estriol (uE3), and inhibin A were assayed at 14+0 to 22+0 weeks. We reviewed all antenatal medical screening records and assessed the relationships of EPV of ultrasound examination, maternal characteristics, and serum markers by using multiple logistic regression analysis. RESULTS Thirteen of the 351 women (3.7%) developed PE in singleton pregnancy. The gestational age at delivery was significantly different between the normal and PE group (p < .001). In the PE group, the placental weight at delivery was not statistically different between the normal and the PE group. The EPV at the first trimester was significantly lower in women with PE compared to those without PE (p = .002). In addition, we predicted PE using combined maternal age, BMI, and EPV, which were achieving an area under the curve of 0.83 overall. CONCLUSION A risk prediction model of PE, which combined maternal age, BMI, and EPV can be adopted for the screening of PE at the first trimester in singleton pregnancy.
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Affiliation(s)
- Young Ran Kim
- Department of Obstetrics and Gynecology, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam, Korea
| | - Inkyung Jung
- Division of Biostatistics, Department of Biomedical Systems Informatics, Yonsei University College of Medicine, Seoul, Korea
| | - Goeun Park
- Division of Biostatistics, Department of Biomedical Systems Informatics, Yonsei University College of Medicine, Seoul, Korea
| | - Sung Woon Chang
- Department of Obstetrics and Gynecology, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam, Korea
| | - Hee Young Cho
- Department of Obstetrics and Gynecology, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam, Korea
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15
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Schwartz N, Siegal J, Rourke A, Sehgal CM. Placental Pulsatility: Quantitative Assessment of Placental Bed Vasculature by 2-Dimensional Doppler Cine Imaging. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2019; 38:471-479. [PMID: 30121962 PMCID: PMC6347511 DOI: 10.1002/jum.14720] [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] [Received: 02/16/2018] [Revised: 05/17/2018] [Accepted: 05/20/2018] [Indexed: 06/08/2023]
Abstract
OBJECTIVES Vascular resistance is known to be one of the determinants of pulsatile flow. This study aimed to investigate whether quantitative 2-dimensional Doppler ultrasound can capture and evaluate the pulsatility within the placental bed vasculature. METHODS The placental bed vasculature was imaged by directional power Doppler ultrasound. Ten-second cine clips were recorded by using standardized machine settings. A region of interest with a prominent Doppler signal in the uteroplacental interface was analyzed for the percentage of vascularity to generate a time-vascularity waveform. A vascular pulsatility index representing variation over the cardiac cycle was calculated by the ratio of the systolic-diastolic difference in vascularity to the mean vascularity. The acquisitions were repeated with 6 different pulse repetition frequencies (PRFs) and 3 wall motion filter (WMF) settings to evaluate their impact on the Doppler measurements. RESULTS Ten sets of cine clips were analyzed for this study. The pulsatile nature of the vascularity was readily apparent in each cine clip. The measured time-vascularity waveforms showed uniform cyclic variation in vascularity over the cardiac cycle, with systolic vascularity significantly higher than diastolic vascularity at each combination of PRF and WMF (P < .05). A gradual increase in the vascular pulsatility index was observed with an increasing PRF or WMF. Normalization of systolic-to-diastolic measurement provided a stable vascular assessment across the range of PRFs. CONCLUSIONS Doppler cine clips provide a dynamic representation of the placental bed vasculature and a novel analytic approach to quantitatively evaluating the pulsatility of this critical vascular network. Further work is warranted to explore the reproducibility and clinical potential of this approach.
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Affiliation(s)
- Nadav Schwartz
- Maternal Child Health Research Center, Department of Obstetrics and Gynecology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Julia Siegal
- Maternal Child Health Research Center, Department of Obstetrics and Gynecology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Aaron Rourke
- Department of Radiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Chandra M. Sehgal
- Department of Radiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
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