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Dietrich S, Aigner CS, Mayer J, Kolbitsch C, Schulz-Menger J, Schaeffter T, Schmitter S. Motion-compensated fat-water imaging for 3D cardiac MRI at ultra-high fields. Magn Reson Med 2022; 87:2621-2636. [PMID: 35092090 DOI: 10.1002/mrm.29144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 11/23/2021] [Accepted: 12/14/2021] [Indexed: 12/16/2022]
Abstract
PURPOSE Respiratory motion-compensated (MC) 3D cardiac fat-water imaging at 7T. METHODS Free-breathing bipolar 3D triple-echo gradient-recalled-echo (GRE) data with radial phase-encoding (RPE) trajectory were acquired in 11 healthy volunteers (7M\4F, 21-35 years, mean: 30 years) with a wide range of body mass index (BMI; 19.9-34.0 kg/m2 ) and volunteer tailored B 1 + shimming. The bipolar-corrected triple-echo GRE-RPE data were binned into different respiratory phases (self-navigation) and were used for the estimation of non-rigid motion vector fields (MF) and respiratory resolved (RR) maps of the main magnetic field deviations (ΔB0 ). RR ΔB0 maps and MC ΔB0 maps were compared to a reference respiratory phase to assess respiration-induced changes. Subsequently, cardiac binned fat-water images were obtained using a model-based, respiratory motion-corrected image reconstruction. RESULTS The 3D cardiac fat-water imaging at 7T was successfully demonstrated. Local respiration-induced frequency shifts in MC ΔB0 maps are small compared to the chemical shifts used in the multi-peak model. Compared to the reference exhale ΔB0 map these changes are in the order of 10 Hz on average. Cardiac binned MC fat-water reconstruction reduced respiration induced blurring in the fat-water images, and flow artifacts are reduced in the end-diastolic fat-water separated images. CONCLUSION This work demonstrates the feasibility of 3D fat-water imaging at UHF for the entire human heart despite spatial and temporal B 1 + and B0 variations, as well as respiratory and cardiac motion.
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Affiliation(s)
- Sebastian Dietrich
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany
| | | | - Johannes Mayer
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany
| | - Christoph Kolbitsch
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany
| | - Jeanette Schulz-Menger
- Experimental and Clinical Research Center, A Joint Cooperation between the Charité Medical Faculty and the Max-Delbrueck Center for Molecular Medicine and HELIOS Hospital Berlin Buch, Berlin, Germany.,DZHK (German Center for Cardiovascular Research), Partner Site Berlin, Berlin, Germany.,Helios Clinics Berlin-Buch Department of Cardiology and Nephrology, Berlin, Germany
| | - Tobias Schaeffter
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany.,Department of Medical Engineering, Technische Universität Berlin, Germany
| | - Sebastian Schmitter
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany.,Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, Minnesota, USA
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Zhu A, Reeder SB, Johnson KM, Nguyen SM, Golos TG, Shimakawa A, Muehler MR, Francois CJ, Bird IM, Fain SB, Shah DM, Wieben O, Hernando D. Evaluation of a motion-robust 2D chemical shift-encoded technique for R2* and field map quantification in ferumoxytol-enhanced MRI of the placenta in pregnant rhesus macaques. J Magn Reson Imaging 2019; 51:580-592. [PMID: 31276263 DOI: 10.1002/jmri.26849] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 06/19/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND 3D chemical shift-encoded (CSE)-MRI techniques enable assessment of ferumoxytol concentration but are unreliable in the presence of motion. PURPOSE To evaluate a motion-robust 2D-sequential CSE-MRI for R2* and B0 mapping in ferumoxytol-enhanced MRI of the placenta. STUDY TYPE Prospective. ANIMAL MODEL Pregnant rhesus macaques. FIELD STRENGTH/SEQUENCE 3.0T/CSE-MRI. ASSESSMENT 2D-sequential CSE-MRI was compared with 3D respiratory-gated CSE-MRI in placental imaging of 11 anesthetized animals at multiple timepoints before and after ferumoxytol administration, and in ferumoxytol phantoms (0 μg/mL-440 μg/mL). Motion artifacts of CSE-MRI in 10 pregnant women without ferumoxytol administration were assessed retrospectively by three blinded readers (4-point Likert scale). The repeatability of CSE-MRI in seven pregnant women was also prospectively studied. STATISTICAL TESTS Placental R2* and boundary B0 field measurements (ΔB0) were compared between 2D-sequential and 3D respiratory-gated CSE-MRI using linear regression and Bland-Altman analysis. RESULTS In phantoms, a slope of 0.94 (r2 = 0.99, concordance correlation coefficient ρ = 0.99), and bias of -4.8 s-1 (limit of agreement [LOA], -41.4 s-1 , +31.8 s-1 ) in R2*, and a slope of 1.07 (r2 = 1.00, ρ = 0.99) and bias of 11.4 Hz (LOA -12.0 Hz, +34.8 Hz) in ΔB0 were obtained in 2D CSE-MRI compared with 3D CSE-MRI for reference R2* ≤390 s-1 . In animals, a slope of 0.92 (r2 = 0.97, ρ = 0.98) and bias of -2.2 s-1 (LOA -55.6 s-1 , +51.3 s-1 ) in R2*, and a slope of 1.05 (r2 = 0.95, ρ = 0.97) and bias of 0.4 Hz (LOA -9.0 Hz, +9.7 Hz) in ΔB0 were obtained. In humans, motion-impaired R2* maps in 3D CSE-MRI (Reader 1: 1.8 ± 0.6, Reader 2: 1.3 ± 0.7, Reader 3: 1.9 ± 0.6), while 2D CSE-MRI was motion-free (Reader 1: 2.9 ± 0.3, Reader 2: 3.0 ± 0, Reader 3: 3.0 ± 0). A mean difference of 0.66 s-1 and coefficient of repeatability of 9.48 s-1 for placental R2* were observed in the repeated 2D CSE-MRI. DATA CONCLUSION 2D-sequential CSE-MRI provides accurate R2* and B0 measurements in ferumoxytol-enhanced placental MRI of animals in the presence of respiratory motion, and motion-robustness in human placental imaging. LEVEL OF EVIDENCE 1 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2020;51:580-592.
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Affiliation(s)
- Ante Zhu
- Department of Biomedical Engineering, University of Wisconsin, Madison, Wisconsin, USA.,Department of Radiology, University of Wisconsin, Madison, Wisconsin, USA
| | - Scott B Reeder
- Department of Biomedical Engineering, University of Wisconsin, Madison, Wisconsin, USA.,Department of Radiology, University of Wisconsin, Madison, Wisconsin, USA.,Department of Medical Physics, University of Wisconsin, Madison, Wisconsin, USA.,Department of Medicine, University of Wisconsin, Madison, Wisconsin, USA.,Department of Emergency Medicine, University of Wisconsin, Madison, Wisconsin, USA
| | - Kevin M Johnson
- Department of Radiology, University of Wisconsin, Madison, Wisconsin, USA.,Department of Medical Physics, University of Wisconsin, Madison, Wisconsin, USA
| | - Sydney M Nguyen
- Wisconsin National Primate Research Center, University of Wisconsin, Madison, Wisconsin, USA.,Department of Obstetrics and Gynecology, University of Wisconsin, Madison, Wisconsin, USA
| | - Thaddeus G Golos
- Wisconsin National Primate Research Center, University of Wisconsin, Madison, Wisconsin, USA.,Department of Obstetrics and Gynecology, University of Wisconsin, Madison, Wisconsin, USA.,Department of Comparative Biosciences, University of Wisconsin, Madison, Wisconsin, USA
| | - Ann Shimakawa
- Global MR Applications and Workflow, GE Healthcare, Menlo Park, California, USA
| | - Matthias R Muehler
- Department of Radiology, University of Wisconsin, Madison, Wisconsin, USA
| | | | - Ian M Bird
- Department of Comparative Biosciences, University of Wisconsin, Madison, Wisconsin, USA
| | - Sean B Fain
- Department of Biomedical Engineering, University of Wisconsin, Madison, Wisconsin, USA.,Department of Radiology, University of Wisconsin, Madison, Wisconsin, USA.,Department of Medical Physics, University of Wisconsin, Madison, Wisconsin, USA
| | - Dinesh M Shah
- Department of Obstetrics and Gynecology, University of Wisconsin, Madison, Wisconsin, USA
| | - Oliver Wieben
- Department of Radiology, University of Wisconsin, Madison, Wisconsin, USA.,Department of Medical Physics, University of Wisconsin, Madison, Wisconsin, USA
| | - Diego Hernando
- Department of Biomedical Engineering, University of Wisconsin, Madison, Wisconsin, USA.,Department of Radiology, University of Wisconsin, Madison, Wisconsin, USA.,Department of Medical Physics, University of Wisconsin, Madison, Wisconsin, USA.,Department of Electrical and Computer Engineering, University of Wisconsin, Madison, Wisconsin, USA
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Liu J, Peters DC, Drangova M. Method of B0 mapping with magnitude-based correction for bipolar two-point Dixon cardiac MRI. Magn Reson Med 2016; 78:1862-1869. [PMID: 27933641 DOI: 10.1002/mrm.26569] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 11/14/2016] [Accepted: 11/14/2016] [Indexed: 12/22/2022]
Abstract
PURPOSE The conventional two-point (2pt) Dixon technique explicitly estimates B0 map by performing phase unwrapping. When signal loss, phase singularity, artifacts, or spatially isolated regions corrupt the measured phase images, this unwrapping-based technique will face difficulty. This work aims to improve the reliability of B0 mapping by performing unwrapping error correction. METHOD To detect the unwrapping-caused phase errors, we determined a magnitude-based fat/water mask and used it as reference to identify pixels being mismatched by the phase-based mask, which was derived from the B0-corrected phase term of the Hermitian product between echoes. Then, we corrected the afore-determined phase error on a region-by-region basis. We tested the developed method with nine patients' data, and the results were compared with a well-established region-growing technique. RESULTS By adding the step to correct unwrapping-caused error, we improved the robustness of B0 mapping, resulting in better fat-water separation when compared with the conventional 2pt and the phasor-based region-growing techniques. CONCLUSION We showed the feasibility of B0 mapping with bipolar 2pt human cardiac data. The software is freely available to the scientific community. Magn Reson Med 78:1862-1869, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Junmin Liu
- Imaging Research Laboratories, Robarts Research Institute, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Dana C Peters
- Department of Radiology and Biomedical Imaging, Yale Medical School, New Haven, Connecticut, USA
| | - Maria Drangova
- Imaging Research Laboratories, Robarts Research Institute, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada.,Department of Medical Biophysics, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
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Henze Bancroft LC, Strigel RM, Hernando D, Johnson KM, Kelcz F, Kijowski R, Block WF. Utilization of a balanced steady state free precession signal model for improved fat/water decomposition. Magn Reson Med 2015; 75:1269-77. [PMID: 25946145 DOI: 10.1002/mrm.25728] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 03/10/2015] [Accepted: 03/20/2015] [Indexed: 12/21/2022]
Abstract
PURPOSE Chemical shift based fat/water decomposition methods such as IDEAL are frequently used in challenging imaging environments with large B0 inhomogeneity. However, they do not account for the signal modulations introduced by a balanced steady state free precession (bSSFP) acquisition. Here we demonstrate improved performance when the bSSFP frequency response is properly incorporated into the multipeak spectral fat model used in the decomposition process. THEORY AND METHODS Balanced SSFP allows for rapid imaging but also introduces a characteristic frequency response featuring periodic nulls and pass bands. Fat spectral components in adjacent pass bands will experience bulk phase offsets and magnitude modulations that change the expected constructive and destructive interference between the fat spectral components. A bSSFP signal model was incorporated into the fat/water decomposition process and used to generate images of a fat phantom, and bilateral breast and knee images in four normal volunteers at 1.5 Tesla. RESULTS Incorporation of the bSSFP signal model into the decomposition process improved the performance of the fat/water decomposition. CONCLUSION Incorporation of this model allows rapid bSSFP imaging sequences to use robust fat/water decomposition methods such as IDEAL. While only one set of imaging parameters were presented, the method is compatible with any field strength or repetition time.
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Affiliation(s)
- Leah C Henze Bancroft
- University of Wisconsin-Madison, Department of Medical Physics, Wisconsin Institutes for Medical Research, Madison, Wisconsin, USA
| | - Roberta M Strigel
- University of Wisconsin-Madison, Department of Medical Physics, Wisconsin Institutes for Medical Research, Madison, Wisconsin, USA.,University of Wisconsin School of Medicine and Public health, Department of Radiology, Madison, Wisconsin, USA.,University of Wisconsin Carbone Cancer Center, Wisconsin Institutes for Medical Research, Madison, Wisconsin, USA
| | - Diego Hernando
- University of Wisconsin-Madison, Department of Radiology, Wisconsin Institutes for Medical Research, Madison, Wisconsin, USA
| | - Kevin M Johnson
- University of Wisconsin-Madison, Department of Medical Physics, Wisconsin Institutes for Medical Research, Madison, Wisconsin, USA
| | - Frederick Kelcz
- University of Wisconsin School of Medicine and Public health, Department of Radiology, Madison, Wisconsin, USA
| | - Richard Kijowski
- University of Wisconsin School of Medicine and Public health, Department of Radiology, Madison, Wisconsin, USA
| | - Walter F Block
- University of Wisconsin-Madison, Department of Medical Physics, Wisconsin Institutes for Medical Research, Madison, Wisconsin, USA.,University of Wisconsin-Madison, Department of Radiology, Wisconsin Institutes for Medical Research, Madison, Wisconsin, USA.,University of Wisconsin-Madison, Department of Biomedical Engineering, Wisconsin Institutes for Medical Research, Madison, Wisconsin
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Sharma SD, Artz NS, Hernando D, Horng DE, Reeder SB. Improving chemical shift encoded water-fat separation using object-based information of the magnetic field inhomogeneity. Magn Reson Med 2014; 73:597-604. [PMID: 24585487 DOI: 10.1002/mrm.25163] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 12/18/2013] [Accepted: 01/14/2014] [Indexed: 12/11/2022]
Abstract
PURPOSE The purpose of this work was to improve the robustness of existing chemical shift encoded water-fat separation methods by incorporating object-based information of the B0 field inhomogeneity. THEORY The primary challenge in water-fat separation is the estimation of phase shifts that arise from B0 field inhomogeneity, which is composed of the background field and susceptibility-induced field. The susceptibility-induced field can be estimated if the susceptibility distribution is known or can be approximated. In this work, the susceptibility distribution is approximated from the source images using the known susceptibility values of water, fat, and air. The field estimate is then demodulated from the source images before water-fat separation. METHODS Chemical shift encoded source images were acquired in anatomical regions that are prone to water-fat swaps. The images were processed using algorithms from the ISMRM Fat-Water Toolbox, with and without the object-based field map information. The estimates were compared to examine the benefit of using the object-based field map information. RESULTS Multiple cases are shown in which water-fat swaps were avoided by using the object-based information of the B0 field map. CONCLUSION Object-based information of the B0 field may improve the robustness of existing chemical shift encoded water-fat separation methods.
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Affiliation(s)
- Samir D Sharma
- Department of Radiology, University of Wisconsin, Madison, Wisconsin, USA
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