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Three-dimensional, time-resolved (4D) relative pressure mapping using magnetic resonance imaging
2000
Journal of Magnetic Resonance Imaging
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The feasibility of performing 4D pressure mapping in vivo is also demonstrated. ...
We describe here a method for generating relative pressure maps from magnetic resonance velocity data in three spatial and one temporal dimension (4D). ...
ACKNOWLEDGEMENTS The authors wish to thank Miho Tyszka for assistance with data acquisition, Seth Blumberg for help coding parts of the pressure algorithm and Al Barr for use of the Caltech graphics laboratory ...
doi:10.1002/1522-2586(200008)12:2<321::aid-jmri15>3.0.co;2-2
pmid:10931596
fatcat:ogi236smv5fsdeeonp5i2wufuq
Velocity Measurement in Carotid Artery: Quantitative Comparison of Time-Resolved 3D Phase-Contrast MRI and Image-based Computational Fluid Dynamics
2015
Iranian Journal of Radiology
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TR 3D PC MRI was performed on a 3 T scanner to measure velocity in carotid bifurcation. 3D anatomical model for CFD was created using images obtained from time-of-flight MR angiography. ...
PC MRI represented a good estimation of main flow patterns inside the vasculature, which seems to be acceptable for clinical use. ...
In this work, 3D geometrical model for CFD was constructed from high resolution time-of-flight MR angiograms that provided more accurate model than phase contrast magnitude images; however, in PC MRI, ...
doi:10.5812/iranjradiol.18286
pmid:26793288
pmcid:PMC4711029
fatcat:yvi3zikuxnatpkexlm7tbifski
MR elastography at 1 Hz of gelatin phantoms using 3D or 4D acquisition
2018
Journal of magnetic resonance (San Diego, Calif. 1997 : Print)
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Quantitative flow (QFLOW) MR techniques were used to phase encode 1 Hz motions as a function of gradient direction using 3D or 4D acquisition; 4D acquisition was twice as fast and yielded comparable motion ...
Signal to noise ratio (SNR) was 94 ± 17 for 3D and dropped to 69 ± 10 for the faster 4D acquisition, but yielded octahedral shear stress and shear modulus maps of high quality that differed by only about ...
Figure 10 : 10 Real shear modulus maps for Phantom 2 (see fig 5) actuated at 1 Hz using 3D or 4D acquisition. Image is based solely on stiffness, not relaxation. ...
doi:10.1016/j.jmr.2018.08.012
pmid:30241018
pmcid:PMC6235749
fatcat:g372u5hvufg4zbv6fmhmrw427a
Noninvasive pressure difference mapping derived from 4D flow MRI in patients with unrepaired and repaired aortic coarctation
2014
Cardiovascular Diagnosis and Therapy
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Pressure difference maps derived from 4D flow MRI can depict alterations of spatial pressure distribution in patients with repaired and unrepaired aortic coarctation. ...
Image analysis was performed with in-house developed image processing software. Relative pressures were computed based on the Navier-Stokes equation. ...
Computation of relative pressure maps from the flow field consists of two major steps (13) . ...
doi:10.3978/j.issn.2223-3652.2014.03.03
pmid:24834408
pmcid:PMC3996241
fatcat:ourn7m2jezdn3grxz4zkk5f3ki
4D flow MRI andT1-Mapping: Assessment of altered cardiac hemodynamics and extracellular volume fraction in hypertrophic cardiomyopathy
2015
Journal of Magnetic Resonance Imaging
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Conclusions-The integration of 4D-flow and T 1 -mapping-MRI allowed for the evaluation of tissue and flow abnormalities in HCM patients. ...
Methods and Results-Cardiac MRI including 4D flow (field strength=1.5T, resolution=2.1-4.0×2.1-4.0×2.5-3.2mm 3 ; venc=150-250cm/s; TE/TR/FA=2.2-2.5ms/4.6-4.9ms/15°) for the invivo assessment of 3D blood ...
Acknowledgments This work was supported by the National Institute of Health (NIH) National Heart, Lung, and Blood Institute (NHLBI) grants R01HL115828, K25HL119608 ...
doi:10.1002/jmri.24962
pmid:26227419
pmcid:PMC4850842
fatcat:ucgz5bn3yfatnh5z7h3cqtcexm
Validation of 4D Flow based relative pressure maps in aortic flows
2021
Medical Image Analysis
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In this work we provide a validation and comparison with phantom and clinical patient data of pressure difference maps estimators. ...
We compare the classical Pressure Poisson Estimator (PPE) and the new Stokes Estimator (STE) against catheter pressure measurements under a variety of stenosis severities and flow intensities. ...
Relative pressure maps are reconstructed from 4D Flow data by means of the Pressure Poisson Estimator (PPE) approach (Ebbers et al., 2002; Ebbers and Farnebäck, 2009; Krittian et al., 2012) and the Stokes ...
doi:10.1016/j.media.2021.102195
pmid:34419837
fatcat:hvuzb5rbmnbvxnwnxhgbslks7i
4D flow cardiovascular magnetic resonance consensus statement
2015
Journal of Cardiovascular Magnetic Resonance
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Derived flow parameters, generally needing further development or validation for clinical use, include measurements of wall shear stress, pressure difference, turbulent kinetic energy, and intracardiac ...
Derived flow parameters, generally needing further development or validation for clinical use, include measurements of wall shear stress, pressure difference, turbulent kinetic energy, and intracardiac ...
Relative Pressure Fields [128, 129, 131] Relative blood pressure field Noninvasive estimation of pressure differences Pressure field calculations based on MR velocity data do not take turbulence effects ...
doi:10.1186/s12968-015-0174-5
pmid:26257141
pmcid:PMC4530492
fatcat:rqx4ao2mnbhgzfp7wcayupn6km
Bridging the gap between measurements and modelling: a cardiovascular functional avatar
2017
Scientific Reports
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The personalized model is created using flow data from four-dimensional magnetic resonance imaging and cuff pressure measurements in the brachial artery. ...
Both quantitatively and qualitatively, the model-based results agreed well with the pressure and flow measurements obtained in vivo for each subject. ...
For extracting flows along the aorta, a 4D PC-MR angiogram was derived from the 4D Flow MRI data to identify the locations of the analysis planes F3 to F5. ...
doi:10.1038/s41598-017-06339-0
pmid:28740184
pmcid:PMC5524911
fatcat:dty66vvyknelppjh2csmym4zna
Assessment of turbulent flow effects on the vessel wall using four-dimensional flow MRI
2016
Magnetic Resonance in Medicine
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Near-wall TKE estimates from MR simulations have good agreement to CFD-derived ground truth (mean R 2 = 0.90). Maps of near-wall TKE have strong visual correspondence to tWSS. ...
Conclusion Near-wall estimation of TKE permits assessment of relative maps of tWSS, but direct estimation of tWSS is challenging due to limitations in spatial resolution. ...
Grant support:
Swedish Research Council, Medical Research Council of Southeast Sweden (FORSS) ...
doi:10.1002/mrm.26308
pmid:27350049
fatcat:26t26wrgpzd4niv32yafnsqqd4
A finite-element approach to the direct computation of relative cardiovascular pressure from time-resolved MR velocity data
2012
Medical Image Analysis
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Input information is provided by enhanced 4D flow data and derived MR domain masking. ...
A subsequent evaluation of pressure differences in enclosed vascular compartments is a further step which is currently not directly available from such data. ...
Acknowledgments The authors want to express their gratitude to all the people who have contributed to the OpenCMISS project during the last couple of years. ...
doi:10.1016/j.media.2012.04.003
pmid:22626833
pmcid:PMC3387378
fatcat:mzx7aiezdvdqhktxtupwyi2rt4
4DFlowNet: Super-Resolution 4D Flow MRI using Deep Learning and Computational Fluid Dynamics
[article]
2020
arXiv
pre-print
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We also tested the 4DFlowNet in actual 4D flow MR images of a phantom and normal volunteer data, and demonstrated comparable results with the actual flow rate measurements giving an absolute relative error ...
Our novel 4DFlowNet network was trained on this synthetic 4D flow data and was capable in producing noise-free super resolution 4D flow phase images with upsample factor of 2. ...
Acknowledgments The authors wish to thank the funders.
4DFlowNet: Super-Resolution 4D-Flow MRI ...
arXiv:2004.07035v1
fatcat:lcekut4pizaqveoq7s7vwhteqi
Magnetic Resonance Measurement of Turbulent Kinetic Energy for the Estimation of Irreversible Pressure Loss in Aortic Stenosis
2013
JACC Cardiovascular Imaging
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Post-stenotic pressure loss is largely caused by dissipation of turbulent kinetic energy into heat. Recent developments in magnetic resonance flow imaging permit noninvasive estimation of TKE. ...
Direct measurement of TKE by magnetic resonance flow imaging may, with further validation, be used to estimate irreversible pressure loss in aortic stenosis. (J Am Coll Cardiol Img 2013;6:64 -71) ...
Others have shown that relative pressure fields can be computed from 4D PC-MRI velocity data (36, 37) . ...
doi:10.1016/j.jcmg.2012.07.017
pmid:23328563
pmcid:PMC3624082
fatcat:e6utp7m5w5f6jg7o53ou5vqbxa
4DFlowNet: Super-Resolution 4D Flow MRI Using Deep Learning and Computational Fluid Dynamics
2020
Frontiers in Physics
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We also tested the 4DFlowNet in actual 4D flow MR images of a phantom and normal volunteer data, and demonstrated comparable results with the actual flow rate measurements giving an absolute relative error ...
Our novel 4DFlowNet network was trained on this synthetic 4D flow data and was capable in producing noise-free super resolution 4D flow phase images with upsample factor of 2. ...
AUTHOR CONTRIBUTIONS All authors participated in conception and design of the study, interpretation of data, revision of the manuscript, and final approval of the submitted manuscript. ...
doi:10.3389/fphy.2020.00138
fatcat:yx5h5ufz7za2haftnpbvvr3foy
Four-Dimensional Image Reconstruction Strategies in Cardiac-Gated and Respiratory-Gated PET Imaging
2013
PET Clinics
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The development of advanced 4D physical anthropomorphic phantoms and computational models will benefit research in cardiac-gated and respiratory-gated PET imaging. ...
Direct four-dimensional (4D) PET image reconstruction incorporating motion compensation provides a very promising alternative to this problem. ...
The motion field estimated from PET images, cine MR images, and tagged MR images was compared. ...
doi:10.1016/j.cpet.2012.10.005
pmid:27157815
fatcat:wfqcow3fnnfv7pt2jg4i66fotq
4D Flow MRI hemodynamic benchmarking of surgical bioprosthetic valves
2020
Magnetic Resonance Imaging
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≥ 0.042) and similar TPGs (p ≥ 0.25). 4D Flow TPGs estimations strongly correlated against ground-truth data from pressure transducers; viscous energy dissipation proved to be inversely proportional to ...
We exploited 4-dimensional flow magnetic resonance imaging (4D Flow), combined with a standardized in vitro setting, to establish a comprehensive benchmark for the systematic hemodynamic comparison of ...
The authors thank Denis Tresova and Elvis Tresova for their valuable assistance in 4D Flow data acquisitions. ...
doi:10.1016/j.mri.2020.01.006
pmid:31981709
fatcat:5yocjff3h5axdolduywlwbkk7e
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