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Quantification of Thoracic Blood Flow Using Volumetric Magnetic Resonance Imaging With Radial Velocity Encoding

Alex Frydrychowicz, Oliver Wieben, Eric Niespodzany, Scott B. Reeder, Kevin M. Johnson, Christopher J. François
2013 Investigative Radiology  
Time-resolved 3-dimensional flow-sensitive MRI (4D-Flow-MRI) using PC-VIPR was performed with a velocity sensitivity V enc =150cm/s reconstructed to 20 time frames at 1.4mm isotropic spatial resolution  ...  Objectives-To validate radially undersampled 5-point velocity-encoded time-resolved flowsensitive MRI ("PC-VIPR") for quantification of ascending aortic (AAO) and main pulmonary artery (MPA) flow in-vivo  ...  University of Wisconsin -Madison.  ... 
doi:10.1097/rli.0b013e31829a4f2f pmid:23857136 pmcid:PMC3823671 fatcat:hc4cer7trjen3ccth3sywm2juu

Rapid Left-to-Right Shunt Quantification in Children by Phase-Contrast Magnetic Resonance Imaging Combined With Sensitivity Encoding (SENSE)

P. Beerbaum
2003 Circulation  
Background-Parallel imaging by sensitivity encoding (SENSE) may considerably reduce scan time in MRI.  ...  Conclusions-PC-MRI for flow quantitation may be combined with SENSE to achieve a substantive reduction of scanning time.  ...  We thank Kerstin Berkemeier, RN, for data postprocessing and Hermann Esdorn, MD, and Andreas Peterschröder, MD, for data acquisition.  ... 
doi:10.1161/01.cir.0000087603.97036.c2 pmid:12939211 fatcat:ubcroy53irg4po2764daiaesja

Aortic Pulse Wave Velocities Using Real-Time Phase-Contrast MRI

Arun A. Joseph, Martin Fasshauser, Klaus-Dietmar Merboldt, Jens Frahm
2015 Open Medical Imaging Journal  
A cross-correlation analysis of the same data resulted in 2.9 to 3.3 m s -1 and 3.3 to 3.7 m s -1 , respectively.  ...  Results: For the time-to-upslope analysis mean pulse wave velocities ranged from 3.5 to 3.9 m s -1 for real-time PC MRI and from 3.5 to 3.8 m s -1 for cine PC MRI.  ...  ACKNOWLEDGEMENTS We are grateful for financial support (A.A.J.) by the DZHK (German Centre for Cardiovascular Research) and BMBF (German Ministry of Education and Research).  ... 
doi:10.2174/1874347101509010009 fatcat:v4rosjrttvhdlbz5tvf6eohujq

Quantitative Cerebrovascular Reactivity in Normal Aging: Comparison Between Phase-Contrast and Arterial Spin Labeling MRI

Kamil Taneja, Peiying Liu, Cuimei Xu, Monroe Turner, Yuguang Zhao, Dema Abdelkarim, Binu P. Thomas, Bart Rypma, Hanzhang Lu
2020 Frontiers in Neurology  
CVR can be measured by BOLD MRI but few studies have measured quantitative cerebral blood flow (CBF)-based CVR in the context of aging.  ...  Conclusion: This study compared two quantitative CVR techniques in the context of brain aging and revealed that PC CVR is a more sensitive method for detection of age differences, despite the absence of  ...  PC MRI is a technique to measure blood flow via imaging of flow velocity in blood vessels (28, 30) .  ... 
doi:10.3389/fneur.2020.00758 pmid:32849217 pmcid:PMC7411174 fatcat:lxytor45bvfjlng5on6yftfeem

Noninvasive Quantification of Left-to-Right Shunt in Pediatric Patients : Phase-Contrast Cine Magnetic Resonance Imaging Compared With Invasive Oximetry

P. Beerbaum, H. Korperich, P. Barth, H. Esdorn, J. Gieseke, H. Meyer
2001 Circulation  
Background-Blood flow can be quantified noninvasively by phase-contrast cine MRI (PC-MRI) in adults. Little is known about the feasibility of the method in children with congenital heart disease.  ...  The accuracy of PC-MRI was confirmed by in vitro experiments. Conclusions-Determination of Q p/Q s by PC-MRI in children is quick, safe, and reliable compared with oximetry.  ...  Three flow-vs-time curves (bottom) were obtained in each vessel to assess repeatability of PC-MRI flow measurements.  ... 
doi:10.1161/01.cir.103.20.2476 pmid:11369688 fatcat:tjbimcga6vg2reirborufefqaq

4D flow imaging with MRI

Zoran Stankovic, Bradley D Allen, Julio Garcia, Kelly B Jarvis, Michael Markl
2014 Cardiovascular Diagnosis and Therapy  
The purpose of this review is to describe the methods used for 4D flow MRI acquisition, post-processing and data analysis.  ...  More recently, time-resolved PC-MRI with velocity encoding along all three flow directions and three-dimensional (3D) anatomic coverage (also termed '4D flow MRI') has been developed and applied for the  ...  Data acquisition methods: from 2D PC to 4D flow MRI Standard 2D PC-MRI PC MRI (also sometimes termed 'flow-sensitive MRI' or 'MR velocity mapping') takes advantage of the direct relationship between  ... 
doi:10.3978/j.issn.2223-3652.2014.01.02 pmid:24834414 pmcid:PMC3996243 fatcat:pnogrpykkzcm3phmwccehoi6bi

Phase-contrast MRI and CFD modeling of apparent 3He gas flow in rat pulmonary airways

Kevin R. Minard, Andrew P. Kuprat, Senthil Kabilan, Richard E. Jacob, Daniel R. Einstein, James P. Carson, Richard A. Corley
2012 Journal of magnetic resonance (San Diego, Calif. 1997 : Print)  
One challenge, however, is that PC-MRI provides apparent values of local ³He velocity that not only depend on actual airflow but also on gas diffusion.  ...  Here, both effects are predicted in a live rat using computational fluid dynamics (CFD), and for the first time, simulated patterns of apparent ³He gas velocity are compared with in vivo PC-MRI.  ...  Acknowledgments Research was performed in the Environmental Molecular Sciences Laboratory (a national scientific user facility sponsored by the US Department of Energy's Office of Biological and Environmental  ... 
doi:10.1016/j.jmr.2012.05.007 pmid:22771528 pmcid:PMC3448557 fatcat:vhfxwyjhobc6ff2ucjv4zvwi4y

Development of a graphical user interface and cross manufacturer adaptation of a program for determining the pulse wave velocity in the aorta from phase-contrast magnetic resonance images

Constantin Schareck, Thekla Oechtering, Alex Frydrychowicz, Martin Koch
2018 Current Directions in Biomedical Engineering  
PWV can be determined non-invasively if the blood flow in the aorta is measured via flow-sensitive MRI.  ...  These algorithms were only able to evaluate PC images which were acquired on a Philips tomograph. Therefore they have been extended for the analysis of PC images acquired on a Siemens tomograph.  ...  if the blood flow at least at two different locations in the aorta was measured with flow-sensitive MRI.  ... 
doi:10.1515/cdbme-2018-0114 fatcat:hsjph5dy2vf2boquxmqcwlg7j4

A Hybrid Approach for Cardiac Blood Flow Vortex Ring Identification Based on Optical Flow and Lagrangian Averaged Vorticity Deviation

Ke Yang, Shiqian Wu, Oluwarotimi W. Samuel, Hui Zhang, Dhanjoo N. Ghista, Di Yang, Kelvin K. L. Wong
2021 Frontiers in Physiology  
Objective: The measurement of cardiac blood flow vortex characteristics can help to facilitate the analysis of blood flow dynamics that regulates heart function.  ...  associated with vorticity deviation and the spatial mean of rings, by using phase-contrast magnetic resonance imaging (PC-MRI) datasets as a case study.  ...  Horn-Schunck Optical Flow Based Intermediate PC-MRI Synthesis Analysis Impact of Different Components on the Quality of PC-MRIs For evaluation, we performed a number of groundtruth comparisons using  ... 
doi:10.3389/fphys.2021.698405 pmid:34539430 pmcid:PMC8440940 fatcat:asbvjqz3tjdlhihqm6fx7jnuta

Velocity mapping of the aortic flow at 9.4 T in healthy mice and mice with induced heart failure using time-resolved three-dimensional phase-contrast MRI (4D PC MRI)

Philipp Rene Bovenkamp, Tobias Brix, Florian Lindemann, Richard Holtmeier, Desiree Abdurrachim, Michael T. Kuhlmann, Gustav J. Strijkers, Jörg Stypmann, Klaus H. Hinrichs, Verena Hoerr
2014 Magnetic Resonance Materials in Physics, Biology and Medicine  
In vivo, 4D PC MRI data of the ascending aorta and the pulmonary artery were confirmed by ultrasound, resulting in linear regressions of R 2 > 0.93.  ...  Herein we present the feasibility of 4D PC MRI in terms of qualitative and quantitative flow pattern analysis in mice with transverse aortic constriction (TAC).  ...  Data analysis FID files of the PC MRI datasets were imported into MAT-LAB (The MathWorks, Inc., Natick, MA, USA) for reconstruction.  ... 
doi:10.1007/s10334-014-0466-z pmid:25381179 pmcid:PMC4515240 fatcat:ne2znitv6bawvnwef5ukespgce

Accelerated dual-venc 4D flow MRI for neurovascular applications

Susanne Schnell, Sameer A. Ansari, Can Wu, Julio Garcia, Ian G. Murphy, Ozair A. Rahman, Amir A. Rahsepar, Maria Aristova, Jeremy D. Collins, James C. Carr, Michael Markl
2017 Journal of Magnetic Resonance Imaging  
Results-All 4D flow MRI scans were acquired successfully with an acquisition time of 20±4min. The shared reference scan reduced the total acquisition time by 12.5% compared to two separate scans.  ...  Conclusion-Dual-venc 4D flow MRI exhibits the superior VNR of the low-venc acquisition and reliably incorporates low-and high-velocity fields simultaneously.  ...  (17) and for the post-processsing dualvenc study by Nett et al. (14) PC-VIPR was used to acquire 4D flow MRI data.  ... 
doi:10.1002/jmri.25595 pmid:28152256 pmcid:PMC5464980 fatcat:yin3rs6akjhrhau43f5nxw3raa

Estimation of labeling efficiency in pseudocontinuous arterial spin labeling

Sina Aslan, Feng Xu, Peiying L. Wang, Jinsoo Uh, Uma S. Yezhuvath, Matthias van Osch, Hanzhang Lu
2010 Magnetic Resonance in Medicine  
Third, we compared the labeling efficiency of pCASL MRI under normocapnic and hypercapnic (inhalation of 5% CO2) conditions, and showed that a higher flow velocity in the feeding arteries resulted in a  ...  In summary, our results suggest that labeling efficiency is a critical parameter in pCASL MRI not only in terms of achieving highest sensitivity but also in quantification of absolute CBF in ml/min/100g  ...  The content of this paper does not necessarily reflect the position or the policy of the U.S. government, and no official endorsement should be inferred.  ... 
doi:10.1002/mrm.22245 pmid:20187183 pmcid:PMC2922009 fatcat:7mfanzzcobatbndudp4ywik2iu

Advanced flow MRI: emerging techniques and applications

M. Markl, S. Schnell, C. Wu, E. Bollache, K. Jarvis, A.J. Barker, J.D. Robinson, C.K. Rigsby
2016 Clinical Radiology  
In addition, the intrinsic sensitivity of MRI to motion offers the unique ability to acquire spatially registered blood flow simultaneously with the morphological data, within a single measurement.  ...  This review describes recently developed advanced MRI flow techniques, which allow for more comprehensive evaluation of blood flow characteristics, such as real-time flow imaging, 2D multiple-venc phase  ...  The lack of standardised analysis tools for regional flow quantification and analysis of PC data with three-directional velocity encoding and/or 3D volumetric coverage is currently a major hurdle for their  ... 
doi:10.1016/j.crad.2016.01.011 pmid:26944696 pmcid:PMC4930408 fatcat:uj2am6anmzbw3b5gqehsepapqy

Hemodynamic Measurement Using Four-Dimensional Phase-Contrast MRI: Quantification of Hemodynamic Parameters and Clinical Applications

Hojin Ha, Guk Bae Kim, Jihoon Kweon, Sang Joon Lee, Young-Hak Kim, Deok Hee Lee, Dong Hyun Yang, Namkug Kim
2016 Korean Journal of Radiology  
Recent improvements have been made to the use of time-resolved, three-dimensional phase-contrast (PC) magnetic resonance imaging (MRI), which is also named four-dimensional (4D) PC-MRI or 4D flow MRI,  ...  The present article reviews the principle and analytical procedures of 4D PC-MRI.  ...  Data Analysis To analyze and visualize hemodynamic features using 4D PC-MRI, two approaches are available. The first option is to use commercial analysis tools for 4D PC-MRI.  ... 
doi:10.3348/kjr.2016.17.4.445 pmid:27390537 pmcid:PMC4936168 fatcat:g2ppakxrz5g2tlf6zlwfbivope

Four-dimensional phase contrast magnetic resonance angiography: Potential clinical applications

Alex Frydrychowicz, Christopher J. François, Patrick A. Turski
2011 European Journal of Radiology  
While the basic principle of PC-MRI dates back almost 3 decades, novel time-resolved three-dimensional PC-MRI (4D PC-MRI) approaches have become increasingly researched over the past years.  ...  The attention hemodynamic research has received is partially based on flow-based theories of atherogenesis and arterial remodeling. 4D PC-MRI can be used to calculate flow-related vessel wall parameters  ...  Each frame in the CE VIPR series is then multiplied times the PC VIPR constraining data producing a new time series with nearly the signal to noise ratio and resolution of the 3D PC MRA exam.  ... 
doi:10.1016/j.ejrad.2011.01.094 pmid:21333479 pmcid:PMC3116042 fatcat:ot3ecs4u4jfvfo6bhgewve7bfm
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