1
|
Guo R, Yang S, Wiesner HM, Li Y, Zhao Y, Liang ZP, Chen W, Zhu XH. Mapping intracellular NAD content in entire human brain using phosphorus-31 MR spectroscopic imaging at 7 Tesla. Front Neurosci 2024; 18:1389111. [PMID: 38911598 PMCID: PMC11190064 DOI: 10.3389/fnins.2024.1389111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Accepted: 05/20/2024] [Indexed: 06/25/2024] Open
Abstract
Introduction Nicotinamide adenine dinucleotide (NAD) is a crucial molecule in cellular metabolism and signaling. Mapping intracellular NAD content of human brain has long been of interest. However, the sub-millimolar level of cerebral NAD concentration poses significant challenges for in vivo measurement and imaging. Methods In this study, we demonstrated the feasibility of non-invasively mapping NAD contents in entire human brain by employing a phosphorus-31 magnetic resonance spectroscopic imaging (31P-MRSI)-based NAD assay at ultrahigh field (7 Tesla), in combination with a probabilistic subspace-based processing method. Results The processing method achieved about a 10-fold reduction in noise over raw measurements, resulting in remarkably reduced estimation errors of NAD. Quantified NAD levels, observed at approximately 0.4 mM, exhibited good reproducibility within repeated scans on the same subject and good consistency across subjects in group data (2.3 cc nominal resolution). One set of higher-resolution data (1.0 cc nominal resolution) unveiled potential for assessing tissue metabolic heterogeneity, showing similar NAD distributions in white and gray matter. Preliminary analysis of age dependence suggested that the NAD level decreases with age. Discussion These results illustrate favorable outcomes of our first attempt to use ultrahigh field 31P-MRSI and advanced processing techniques to generate a whole-brain map of low-concentration intracellular NAD content in the human brain.
Collapse
Affiliation(s)
- Rong Guo
- Beckman Institute of Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
- Siemens Medical Solutions USA, Inc., Urbana, IL, United States
| | - Shaolin Yang
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, United States
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States
| | - Hannes M. Wiesner
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States
| | - Yudu Li
- Beckman Institute of Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Yibo Zhao
- Beckman Institute of Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Zhi-Pei Liang
- Beckman Institute of Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Wei Chen
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States
| | - Xiao-Hong Zhu
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States
| |
Collapse
|
2
|
Bozymski B, Emir U, Dydak U, Shen X, Thomas MA, Özen A, Chiew M, Clarke W, Sawiak S. 3D ultra-short echo time 31P-MRSI with rosette k-space pattern: Feasibility and comparison with conventional weighted CSI. RESEARCH SQUARE 2024:rs.3.rs-4223790. [PMID: 38659806 PMCID: PMC11042414 DOI: 10.21203/rs.3.rs-4223790/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Phosphorus-31 magnetic resonance spectroscopic imaging (31P-MRSI) provides valuable non-invasive in vivo information on tissue metabolism but is burdened by poor sensitivity and prolonged scan duration. Ultra-short echo time (UTE) acquisitions minimize signal loss when probing signals with relatively short spin-spin relaxation time (T2), while also preventing first-order dephasing. Here, a three-dimensional (3D) UTE sequence with a rosette k-space trajectory is applied to 31P-MRSI at 3T. Conventional chemical shift imaging (CSI) employs highly regular Cartesian k-space sampling, susceptible to substantial artifacts when accelerated via undersampling. In contrast, this novel sequence's "petal-like" pattern offers incoherent sampling more suitable for compressed sensing (CS). These results showcase the competitive performance of UTE rosette 31P-MRSI against conventional weighted CSI with simulation, phantom, and in vivo leg muscle comparisons.
Collapse
Affiliation(s)
| | - Uzay Emir
- School of Health Sciences, Purdue University
| | | | - Xin Shen
- Radiology and Biomedical Imaging, University of California San Francisco
| | | | - Ali Özen
- Department of Radiology, Medical Physics, Medical Center - University of Freiburg
| | - Mark Chiew
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences
| | - William Clarke
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences
| | - Stephen Sawiak
- Department of Clinical Neuroscience, University of Cambridge
| |
Collapse
|
3
|
Niess F, Strasser B, Hingerl L, Niess E, Motyka S, Hangel G, Krššák M, Gruber S, Spurny-Dworak B, Trattnig S, Scherer T, Lanzenberger R, Bogner W. Reproducibility of 3D MRSI for imaging human brain glucose metabolism using direct ( 2H) and indirect ( 1H) detection of deuterium labeled compounds at 7T and clinical 3T. Neuroimage 2023; 277:120250. [PMID: 37414233 PMCID: PMC11019874 DOI: 10.1016/j.neuroimage.2023.120250] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/25/2023] [Accepted: 06/23/2023] [Indexed: 07/08/2023] Open
Abstract
INTRODUCTION Deuterium metabolic imaging (DMI) and quantitative exchange label turnover (QELT) are novel MR spectroscopy techniques for non-invasive imaging of human brain glucose and neurotransmitter metabolism with high clinical potential. Following oral or intravenous administration of non-ionizing [6,6'-2H2]-glucose, its uptake and synthesis of downstream metabolites can be mapped via direct or indirect detection of deuterium resonances using 2H MRSI (DMI) and 1H MRSI (QELT), respectively. The purpose of this study was to compare the dynamics of spatially resolved brain glucose metabolism, i.e., estimated concentration enrichment of deuterium labeled Glx (glutamate+glutamine) and Glc (glucose) acquired repeatedly in the same cohort of subjects using DMI at 7T and QELT at clinical 3T. METHODS Five volunteers (4 m/1f) were scanned in repeated sessions for 60 min after overnight fasting and 0.8 g/kg oral [6,6'-2H2]-glucose administration using time-resolved 3D 2H FID-MRSI with elliptical phase encoding at 7T and 3D 1H FID-MRSI with a non-Cartesian concentric ring trajectory readout at clinical 3T. RESULTS One hour after oral tracer administration regionally averaged deuterium labeled Glx4 concentrations and the dynamics were not significantly different over all participants between 7T 2H DMI and 3T 1H QELT data for GM (1.29±0.15 vs. 1.38±0.26 mM, p=0.65 & 21±3 vs. 26±3 µM/min, p=0.22) and WM (1.10±0.13 vs. 0.91±0.24 mM, p=0.34 & 19±2 vs. 17±3 µM/min, p=0.48). Also, the observed time constants of dynamic Glc6 data in GM (24±14 vs. 19±7 min, p=0.65) and WM (28±19 vs. 18±9 min, p=0.43) dominated regions showed no significant differences. Between individual 2H and 1H data points a weak to moderate negative correlation was observed for Glx4 concentrations in GM (r=-0.52, p<0.001), and WM (r=-0.3, p<0.001) dominated regions, while a strong negative correlation was observed for Glc6 data GM (r=-0.61, p<0.001) and WM (r=-0.70, p<0.001). CONCLUSION This study demonstrates that indirect detection of deuterium labeled compounds using 1H QELT MRSI at widely available clinical 3T without additional hardware is able to reproduce absolute concentration estimates of downstream glucose metabolites and the dynamics of glucose uptake compared to 2H DMI data acquired at 7T. This suggests significant potential for widespread application in clinical settings especially in environments with limited access to ultra-high field scanners and dedicated RF hardware.
Collapse
Affiliation(s)
- Fabian Niess
- High Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Lazarettgasse 14, Vienna A-1090, Austria.
| | - Bernhard Strasser
- High Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Lazarettgasse 14, Vienna A-1090, Austria
| | - Lukas Hingerl
- High Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Lazarettgasse 14, Vienna A-1090, Austria
| | - Eva Niess
- High Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Lazarettgasse 14, Vienna A-1090, Austria; Christian Doppler Laboratory for MR Imaging Biomarkers (BIOMAK), Austria
| | - Stanislav Motyka
- High Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Lazarettgasse 14, Vienna A-1090, Austria; Christian Doppler Laboratory for MR Imaging Biomarkers (BIOMAK), Austria
| | - Gilbert Hangel
- High Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Lazarettgasse 14, Vienna A-1090, Austria; Department of Neurosurgery, Medical University of Vienna, Austria
| | - Martin Krššák
- Department of Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Austria
| | - Stephan Gruber
- High Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Lazarettgasse 14, Vienna A-1090, Austria; Christian Doppler Laboratory for MR Imaging Biomarkers (BIOMAK), Austria
| | - Benjamin Spurny-Dworak
- Department of Psychiatry and Psychotherapy, Comprehensive Center for Clinical Neurosciences and Mental Health (C3NMH), Medical University of Vienna, Austria
| | - Siegfried Trattnig
- High Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Lazarettgasse 14, Vienna A-1090, Austria; Institute for Clinical Molecular MRI, Karl Landsteiner Society, Pölten 3100St, Austria
| | - Thomas Scherer
- Department of Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Austria
| | - Rupert Lanzenberger
- Department of Psychiatry and Psychotherapy, Comprehensive Center for Clinical Neurosciences and Mental Health (C3NMH), Medical University of Vienna, Austria
| | - Wolfgang Bogner
- High Field MR Center, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Lazarettgasse 14, Vienna A-1090, Austria; Christian Doppler Laboratory for MR Imaging Biomarkers (BIOMAK), Austria
| |
Collapse
|
4
|
Xu J, Chung JJ, Jin T. Chemical exchange saturation transfer imaging of creatine, phosphocreatine, and protein arginine residue in tissues. NMR IN BIOMEDICINE 2023; 36:e4671. [PMID: 34978371 PMCID: PMC9250548 DOI: 10.1002/nbm.4671] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 11/06/2021] [Accepted: 12/02/2021] [Indexed: 05/05/2023]
Abstract
Chemical exchange saturation transfer (CEST) MRI has become a promising technique to assay target proteins and metabolites through their exchangeable protons, noninvasively. The ubiquity of creatine (Cr) and phosphocreatine (PCr) due to their pivotal roles in energy homeostasis through the creatine phosphate pathway has made them prime targets for CEST in the diagnosis and monitoring of disease pathologies, particularly in tissues heavily dependent on the maintenance of rich energy reserves. Guanidinium CEST from protein arginine residues (i.e. arginine CEST) can also provide information about the protein profile in tissue. However, numerous obfuscating factors stand as obstacles to the specificity of arginine, Cr, and PCr imaging through CEST, such as semisolid magnetization transfer, fast chemical exchanges such as primary amines, and the effects of nuclear Overhauser enhancement from aromatic and amide protons. In this review, the specific exchange properties of protein arginine residues, Cr, and PCr, along with their validation, are discussed, including the considerations necessary to target and tune their signal effects through CEST imaging. Additionally, strategies that have been employed to enhance the specificity of these exchanges in CEST imaging are described, along with how they have opened up possible applications of protein arginine residues, Cr and PCr CEST imaging in the study and diagnosis of pathology. A clear understanding of the capabilities and caveats of using CEST to image these vital metabolites and mitigation strategies is crucial to expanding the possibilities of this promising technology.
Collapse
Affiliation(s)
- Jiadi Xu
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Julius Juhyun Chung
- Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Tao Jin
- Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| |
Collapse
|
5
|
Niess F, Strasser B, Hingerl L, Niess E, Motyka S, Hangel G, Krššák M, Gruber S, Spurny-Dworak B, Trattnig S, Scherer T, Lanzenberger R, Bogner W. Reproducibility of 3D MRSI for imaging human brain glucose metabolism using direct ( 2 H) and indirect ( 1 H) detection of deuterium labeled compounds at 7T and clinical 3T. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.04.17.23288672. [PMID: 37131634 PMCID: PMC10153308 DOI: 10.1101/2023.04.17.23288672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Introduction Deuterium metabolic imaging (DMI) and quantitative exchange label turnover (QELT) are novel MR spectroscopy techniques for non-invasive imaging of human brain glucose and neurotransmitter metabolism with high clinical potential. Following oral or intravenous administration of non-ionizing [6,6'- 2 H 2 ]-glucose, its uptake and synthesis of downstream metabolites can be mapped via direct or indirect detection of deuterium resonances using 2 H MRSI (DMI) and 1 H MRSI (QELT), respectively. The purpose of this study was to compare the dynamics of spatially resolved brain glucose metabolism, i.e., estimated concentration enrichment of deuterium labeled Glx (glutamate+glutamine) and Glc (glucose) acquired repeatedly in the same cohort of subjects using DMI at 7T and QELT at clinical 3T. Methods Five volunteers (4m/1f) were scanned in repeated sessions for 60 min after overnight fasting and 0.8g/kg oral [6,6'- 2 H 2 ]-glucose administration using time-resolved 3D 2 H FID-MRSI with elliptical phase encoding at 7T and 3D 1 H FID-MRSI with a non-Cartesian concentric ring trajectory readout at clinical 3T. Results One hour after oral tracer administration regionally averaged deuterium labeled Glx 4 concentrations and the dynamics were not significantly different over all participants between 7T 2 H DMI and 3T 1 H QELT data for GM (1.29±0.15 vs. 1.38±0.26 mM, p=0.65 & 21±3 vs. 26±3 µM/min, p=0.22) and WM (1.10±0.13 vs. 0.91±0.24 mM, p=0.34 & 19±2 vs. 17±3 µM/min, p=0.48). Also, the observed time constants of dynamic Glc 6 data in GM (24±14 vs. 19±7 min, p=0.65) and WM (28±19 vs. 18±9 min, p=0.43) dominated regions showed no significant differences. Between individual 2 H and 1 H data points a weak to moderate negative correlation was observed for Glx 4 concentrations in GM (r=-0.52, p<0.001), and WM (r=-0.3, p<0.001) dominated regions, while a strong negative correlation was observed for Glc 6 data GM (r=- 0.61, p<0.001) and WM (r=-0.70, p<0.001). Conclusion This study demonstrates that indirect detection of deuterium labeled compounds using 1 H QELT MRSI at widely available clinical 3T without additional hardware is able to reproduce absolute concentration estimates of downstream glucose metabolites and the dynamics of glucose uptake compared to 2 H DMI data acquired at 7T. This suggests significant potential for widespread application in clinical settings especially in environments with limited access to ultra-high field scanners and dedicated RF hardware.
Collapse
|
6
|
Sun P, Wu Z, Lin L, Hu G, Zhang X, Wang J. MR-Nucleomics: The study of pathological cellular processes with multinuclear magnetic resonance spectroscopy and imaging in vivo. NMR IN BIOMEDICINE 2023; 36:e4845. [PMID: 36259659 DOI: 10.1002/nbm.4845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 09/28/2022] [Accepted: 10/08/2022] [Indexed: 06/16/2023]
Abstract
Clinical medicine has experienced a rapid development in recent decades, during which therapies targeting specific cellular signaling pathways, or specific cell surface receptors, have been increasingly adopted. While these developments in clinical medicine call for improved precision in diagnosis and treatment monitoring, modern medical imaging methods are restricted mainly to anatomical imaging, lagging behind the requirements of precision medicine. Although positron emission tomography and single photon emission computed tomography have been used clinically for studies of metabolism, their applications have been limited by the exposure risk to ionizing radiation, the subsequent limitation in repeated and longitudinal studies, and the incapability in assessing downstream metabolism. Magnetic resonance spectroscopy (MRS) or spectroscopic imaging (MRSI) are, in theory, capable of assessing molecular activities in vivo, although they are often limited by sensitivity. Here, we review some recent developments in MRS and MRSI of multiple nuclei that have potential as molecular imaging tools in the clinic.
Collapse
Affiliation(s)
- Peng Sun
- Clinical & Technical Support, Philips Healthcare, China
| | - Zhigang Wu
- Clinical & Technical Support, Philips Healthcare, China
| | - Liangjie Lin
- Clinical & Technical Support, Philips Healthcare, China
| | - Geli Hu
- Clinical & Technical Support, Philips Healthcare, China
| | | | - Jiazheng Wang
- Clinical & Technical Support, Philips Healthcare, China
| |
Collapse
|
7
|
Songeon J, Courvoisier S, Xin L, Agius T, Dabrowski O, Longchamp A, Lazeyras F, Klauser A. In vivo magnetic resonance <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow><mml:msup><mml:mrow/> <mml:mrow><mml:mn>31</mml:mn></mml:mrow> </mml:msup> </mml:mrow> </mml:math> P-Spectral Analysis With Neural Networks: 31P-SPAWNN. Magn Reson Med 2023; 89:40-53. [PMID: 36161342 PMCID: PMC9828468 DOI: 10.1002/mrm.29446] [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: 04/20/2022] [Revised: 08/16/2022] [Accepted: 08/18/2022] [Indexed: 01/12/2023]
Abstract
PURPOSE We have introduced an artificial intelligence framework, 31P-SPAWNN, in order to fully analyze phosphorus-31 ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:mrow><mml:msup><mml:mrow/> <mml:mrow><mml:mn>31</mml:mn></mml:mrow> </mml:msup> </mml:mrow> <mml:annotation>$$ {}^{31} $$</mml:annotation></mml:semantics> </mml:math> P) magnetic resonance spectra. The flexibility and speed of the technique rival traditional least-square fitting methods, with the performance of the two approaches, are compared in this work. THEORY AND METHODS Convolutional neural network architectures have been proposed for the analysis and quantification of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:mrow><mml:msup><mml:mrow/> <mml:mrow><mml:mn>31</mml:mn></mml:mrow> </mml:msup> </mml:mrow> <mml:annotation>$$ {}^{31} $$</mml:annotation></mml:semantics> </mml:math> P-spectroscopy. The generation of training and test data using a fully parameterized model is presented herein. In vivo unlocalized free induction decay and three-dimensional <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:mrow><mml:msup><mml:mrow/> <mml:mrow><mml:mn>31</mml:mn></mml:mrow> </mml:msup> </mml:mrow> <mml:annotation>$$ {}^{31} $$</mml:annotation></mml:semantics> </mml:math> P-magnetic resonance spectroscopy imaging data were acquired from healthy volunteers before being quantified using either 31P-SPAWNN or traditional least-square fitting techniques. RESULTS The presented experiment has demonstrated both the reliability and accuracy of 31P-SPAWNN for estimating metabolite concentrations and spectral parameters. Simulated test data showed improved quantification using 31P-SPAWNN compared with LCModel. In vivo data analysis revealed higher accuracy at low signal-to-noise ratio using 31P-SPAWNN, yet with equivalent precision. Processing time using 31P-SPAWNN can be further shortened up to two orders of magnitude. CONCLUSION The accuracy, reliability, and computational speed of the method open new perspectives for integrating these applications in a clinical setting.
Collapse
Affiliation(s)
- Julien Songeon
- Department of Radiology and Medical InformaticsUniversity of GenevaGenevaSwitzerland
| | - Sébastien Courvoisier
- Department of Radiology and Medical InformaticsUniversity of GenevaGenevaSwitzerland,CIBM Center for Biomedical ImagingGenevaSwitzerland
| | - Lijing Xin
- CIBM Center for Biomedical ImagingGenevaSwitzerland,Animal Imaging and TechnologyEcole Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | - Thomas Agius
- Department of Vascular SurgeryCentre Hospitalier Universitaire Vaudois and University of LausanneLausanneSwitzerland
| | - Oscar Dabrowski
- Department of Radiology and Medical InformaticsUniversity of GenevaGenevaSwitzerland
| | - Alban Longchamp
- Department of Vascular SurgeryCentre Hospitalier Universitaire Vaudois and University of LausanneLausanneSwitzerland
| | - François Lazeyras
- Department of Radiology and Medical InformaticsUniversity of GenevaGenevaSwitzerland,CIBM Center for Biomedical ImagingGenevaSwitzerland
| | - Antoine Klauser
- Department of Radiology and Medical InformaticsUniversity of GenevaGenevaSwitzerland,CIBM Center for Biomedical ImagingGenevaSwitzerland
| |
Collapse
|
8
|
Cheng HLM. Emerging MRI techniques for molecular and functional phenotyping of the diseased heart. Front Cardiovasc Med 2022; 9:1072828. [PMID: 36545017 PMCID: PMC9760746 DOI: 10.3389/fcvm.2022.1072828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 11/22/2022] [Indexed: 12/12/2022] Open
Abstract
Recent advances in cardiac MRI (CMR) capabilities have truly transformed its potential for deep phenotyping of the diseased heart. Long known for its unparalleled soft tissue contrast and excellent depiction of three-dimensional (3D) structure, CMR now boasts a range of unique capabilities for probing disease at the tissue and molecular level. We can look beyond coronary vessel blockages and detect vessel disease not visible on a structural level. We can assess if early fibrotic tissue is being laid down in between viable cardiac muscle cells. We can measure deformation of the heart wall to determine early presentation of stiffening. We can even assess how cardiomyocytes are utilizing energy, where abnormalities are often precursors to overt structural and functional deficits. Finally, with artificial intelligence gaining traction due to the high computing power available today, deep learning has proven itself a viable contender with traditional acceleration techniques for real-time CMR. In this review, we will survey five key emerging MRI techniques that have the potential to transform the CMR clinic and permit early detection and intervention. The emerging areas are: (1) imaging microvascular dysfunction, (2) imaging fibrosis, (3) imaging strain, (4) imaging early metabolic changes, and (5) deep learning for acceleration. Through a concerted effort to develop and translate these areas into the CMR clinic, we are committing ourselves to actualizing early diagnostics for the most intractable heart disease phenotypes.
Collapse
Affiliation(s)
- Hai-Ling Margaret Cheng
- The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada,Ted Rogers Centre for Heart Research, Translational Biology & Engineering Program, Toronto, ON, Canada,*Correspondence: Hai-Ling Margaret Cheng,
| |
Collapse
|
9
|
Lopez Kolkovsky AL, Carlier PG, Marty B, Meyerspeer M. Interleaved and simultaneous multi-nuclear magnetic resonance in vivo. Review of principles, applications and potential. NMR IN BIOMEDICINE 2022; 35:e4735. [PMID: 35352440 PMCID: PMC9542607 DOI: 10.1002/nbm.4735] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 03/03/2022] [Accepted: 03/28/2022] [Indexed: 06/14/2023]
Abstract
Magnetic resonance signals from different nuclei can be excited or received at the same time,rendering simultaneous or rapidly interleaved multi-nuclear acquisitions feasible. The advan-tages are a reduction of total scan time compared to sequential multi-nuclear acquisitions or that additional information from heteronuclear data is obtained at thesame time and anatomical position. Information content can be qualitatively increased by delivering a more comprehensive MR-based picture of a transient state (such as an exercise bout). Also, combiningnon-proton MR acquisitions with 1 Hinformation (e.g., dynamic shim updates and motion correction) can be used to improve data quality during long scans and benefits image coregistration. This work reviews the literature on interleaved and simultaneous multi-nuclear MRI and MRS in vivo. Prominent use cases for this methodology in clinical and research applications are brain and muscle, but studies have also been carried out in other targets, including the lung, knee, breast and heart. Simultaneous multi-nuclear measurements in the liver and kidney have also been performed, but exclusively in rodents. In this review, a consistent nomenclature is proposed, to help clarify the terminology used for this principle throughout the literature on in-vivo MR. An overview covers the basic principles, the technical requirements on the MR scanner and the implementations realised either by MR system vendors or research groups, from the early days until today. Considerations regarding the multi-tuned RF coils required and heteronuclear polarisation interactions are briefly discussed, and fields for future in-vivo applications for interleaved multi-nuclear MR pulse sequences are identified.
Collapse
Affiliation(s)
- Alfredo L. Lopez Kolkovsky
- NMR Laboratory, Neuromuscular Investigation CenterInstitute of MyologyParisFrance
- NMR laboratoryCEA, DRF, IBFJParisFrance
| | - Pierre G. Carlier
- NMR Laboratory, Neuromuscular Investigation CenterInstitute of MyologyParisFrance
- NMR laboratoryCEA, DRF, IBFJParisFrance
| | - Benjamin Marty
- NMR Laboratory, Neuromuscular Investigation CenterInstitute of MyologyParisFrance
- NMR laboratoryCEA, DRF, IBFJParisFrance
| | - Martin Meyerspeer
- High‐Field MR Center, Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| |
Collapse
|
10
|
Klauser A, Strasser B, Thapa B, Lazeyras F, Andronesi O. Achieving high-resolution 1H-MRSI of the human brain with compressed-sensing and low-rank reconstruction at 7 Tesla. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2021; 331:107048. [PMID: 34438355 PMCID: PMC8717865 DOI: 10.1016/j.jmr.2021.107048] [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] [Received: 02/05/2021] [Revised: 06/29/2021] [Accepted: 08/08/2021] [Indexed: 06/02/2023]
Abstract
Low sensitivity MR techniques such as magnetic resonance spectroscopic imaging (MRSI) greatly benefit from the gain in signal-to-noise provided by ultra-high field MR. High-resolution and whole-slab brain MRSI remains however very challenging due to lengthy acquisition, low signal, lipid contamination and field inhomogeneity. In this study, we propose an acquisition-reconstruction scheme that combines 1H free-induction-decay (FID)-MRSI sequence, short TR acquisition, compressed sensing acceleration and low-rank modeling with total-generalized-variation constraint to achieve metabolite imaging in two and three dimensions at 7 Tesla. The resulting images and volumes reveal highly detailed distributions that are specific to each metabolite and follow the underlying brain anatomy. The MRSI method was validated in a high-resolution phantom containing fine metabolite structures, and in five healthy volunteers. This new application of compressed sensing acceleration paves the way for high-resolution MRSI in clinical setting with acquisition times of 5 min for 2D MRSI at 2.5 mm and of 20 min for 3D MRSI at 3.3 mm isotropic.
Collapse
Affiliation(s)
- Antoine Klauser
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States; Department of Radiology and Medical Informatics, University of Geneva, Switzerland; Center for Biomedical Imaging (CIBM), Geneva, Switzerland.
| | - Bernhard Strasser
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Bijaya Thapa
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Francois Lazeyras
- Department of Radiology and Medical Informatics, University of Geneva, Switzerland; Center for Biomedical Imaging (CIBM), Geneva, Switzerland
| | - Ovidiu Andronesi
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| |
Collapse
|
11
|
Bogner W, Otazo R, Henning A. Accelerated MR spectroscopic imaging-a review of current and emerging techniques. NMR IN BIOMEDICINE 2021; 34:e4314. [PMID: 32399974 PMCID: PMC8244067 DOI: 10.1002/nbm.4314] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 03/24/2020] [Accepted: 03/30/2020] [Indexed: 05/14/2023]
Abstract
Over more than 30 years in vivo MR spectroscopic imaging (MRSI) has undergone an enormous evolution from theoretical concepts in the early 1980s to the robust imaging technique that it is today. The development of both fast and efficient sampling and reconstruction techniques has played a fundamental role in this process. State-of-the-art MRSI has grown from a slow purely phase-encoded acquisition technique to a method that today combines the benefits of different acceleration techniques. These include shortening of repetition times, spatial-spectral encoding, undersampling of k-space and time domain, and use of spatial-spectral prior knowledge in the reconstruction. In this way in vivo MRSI has considerably advanced in terms of spatial coverage, spatial resolution, acquisition speed, artifact suppression, number of detectable metabolites and quantification precision. Acceleration not only has been the enabling factor in high-resolution whole-brain 1 H-MRSI, but today is also common in non-proton MRSI (31 P, 2 H and 13 C) and applied in many different organs. In this process, MRSI techniques had to constantly adapt, but have also benefitted from the significant increase of magnetic field strength boosting the signal-to-noise ratio along with high gradient fidelity and high-density receive arrays. In combination with recent trends in image reconstruction and much improved computation power, these advances led to a number of novel developments with respect to MRSI acceleration. Today MRSI allows for non-invasive and non-ionizing mapping of the spatial distribution of various metabolites' tissue concentrations in animals or humans, is applied for clinical diagnostics and has been established as an important tool for neuro-scientific and metabolism research. This review highlights the developments of the last five years and puts them into the context of earlier MRSI acceleration techniques. In addition to 1 H-MRSI it also includes other relevant nuclei and is not limited to certain body regions or specific applications.
Collapse
Affiliation(s)
- Wolfgang Bogner
- High‐Field MR Center, Department of Biomedical Imaging and Image‐Guided TherapyMedical University of ViennaViennaAustria
| | - Ricardo Otazo
- Department of Medical PhysicsMemorial Sloan Kettering Cancer CenterNew York, New YorkUSA
| | - Anke Henning
- Max Planck Institute for Biological CyberneticsTübingenGermany
- Advanced Imaging Research Center, UT Southwestern Medical CenterDallasTexasUSA
| |
Collapse
|
12
|
Ma RE, Murdoch JB, Bogner W, Andronesi O, Dydak U. Atlas-based GABA mapping with 3D MEGA-MRSI: Cross-correlation to single-voxel MRS. NMR IN BIOMEDICINE 2021; 34:e4275. [PMID: 32078755 PMCID: PMC7438238 DOI: 10.1002/nbm.4275] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 01/11/2020] [Accepted: 01/23/2020] [Indexed: 06/10/2023]
Abstract
The purpose of this work is to develop and validate a new atlas-based metabolite quantification pipeline for edited magnetic resonance spectroscopic imaging (MEGA-MRSI) that enables group comparisons of brain structure-specific GABA levels. By using brain structure masks segmented from high-resolution MPRAGE images and coregistering these to MEGA-LASER 3D MRSI data, an automated regional quantification of neurochemical levels is demonstrated for the example of the thalamus. Thalamic gamma-aminobutyric acid + coedited macromolecules (GABA+) levels from 21 healthy subjects scanned at 3 T were cross-validated both against a single-voxel MEGA-PRESS acquisition in the same subjects and same scan sessions, as well as alternative MRSI processing techniques (ROI approach, four-voxel approach) using Pearson correlation analysis. In addition, reproducibility was compared across the MRSI processing techniques in test-retest data from 14 subjects. The atlas-based approach showed a significant correlation with SV MEGA-PRESS (correlation coefficient r [GABA+] = 0.63, P < 0.0001). However, the actual values for GABA+, NAA, tCr, GABA+/tCr and tNAA/tCr obtained from the atlas-based approach showed an offset to SV MEGA-PRESS levels, likely due to the fact that on average the thalamus mask used for the atlas-based approach only occupied 30% of the SVS volume, ie, somewhat different anatomies were sampled. Furthermore, the new atlas-based approach showed highly reproducible GABA+/tCr values with a low median coefficient of variance of 6.3%. In conclusion, the atlas-based metabolite quantification approach enables a more brain structure-specific comparison of GABA+ and other neurochemical levels across populations, even when using an MRSI technique with only cm-level resolution. This approach was successfully cross-validated against the typically used SVS technique as well as other different MRSI analysis methods, indicating the robustness of this quantification approach.
Collapse
Affiliation(s)
- Ruoyun E. Ma
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN, USA
- School of Health Sciences, Purdue University, West Lafayette, IN, USA
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, USA
| | | | - Wolfgang Bogner
- High Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Ovidiu Andronesi
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Ulrike Dydak
- School of Health Sciences, Purdue University, West Lafayette, IN, USA
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, USA
| |
Collapse
|
13
|
Ohta H, Vo NMV, Hata J, Terawaki K, Shirakawa T, Okano HJ. Utilizing Dynamic Phosphorous-31 Magnetic Resonance Spectroscopy for the Early Detection of Acute Compartment Syndrome: A Pilot Study on Rats. Diagnostics (Basel) 2021; 11:586. [PMID: 33805144 PMCID: PMC8064087 DOI: 10.3390/diagnostics11040586] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/20/2021] [Accepted: 03/21/2021] [Indexed: 01/15/2023] Open
Abstract
INTRODUCTION Disasters, including terrorism and earthquakes, are significant threats to people and may lead to many people requiring rescue. The longer the rescue takes, the higher the chances of an individual contracting acute compartment syndrome (ACS). ACS is fatal if diagnosed too late, and early diagnosis and treatment are essential. OBJECTIVE To assess the ability of dynamic phosphorus magnetic resonance spectroscopy (31P-MRS) in the early detection of muscular damage in ACS. MATERIALS AND METHODS Six ACS model rats were used for serial 31P-MRS scanning (9.4 Tesla). Skeletal muscle metabolism, represented by the levels of phosphocreatine (PCr), inorganic phosphate (Pi), and adenosine triphosphate (ATP), was assessed. The PCr/(Pi + PCr) ratio, which decreases with ischemia, was compared with simultaneously sampled plasma creatine phosphokinase (CPK), a muscle damage marker. RESULTS The PCr/(Pi + PCr) ratio significantly decreased after inducing ischemia (from 0.86 ± 0.10 to 0.18 ± 0.06; p < 0.05), while CPK did not change significantly (from 89 ± 29.46 to 241.50 ± 113.28; p > 0.05). The intracellular and arterial pH index decreased over time, revealing significant differences at 120 min post-ischemia (from 7.09 ± 0.01 to 6.43 ± 0.13, and from 7.47 ± 0.03 to 7.39 ± 0.04, respectively). In the reperfusion state, the spectra and pH did not return to the original values. CONCLUSIONS The dynamic 31P-MRS technique can rapidly detect changes in muscle bioenergetics. This technique is a promising non-invasive method for determining early muscular damage in ACS.
Collapse
Affiliation(s)
- Hiroki Ohta
- Division of Regenerative Medicine, Research Center for Medical Sciences, The Jikei University School of Medicine, Tokyo 105-8461, Japan; (H.O.); (N.-M.V.V.); (J.H.); (K.T.)
| | - Nhat-Minh Van Vo
- Division of Regenerative Medicine, Research Center for Medical Sciences, The Jikei University School of Medicine, Tokyo 105-8461, Japan; (H.O.); (N.-M.V.V.); (J.H.); (K.T.)
- Department of Radiological Sciences, Tokyo Metropolitan University, Tokyo 116-0012, Japan;
| | - Junichi Hata
- Division of Regenerative Medicine, Research Center for Medical Sciences, The Jikei University School of Medicine, Tokyo 105-8461, Japan; (H.O.); (N.-M.V.V.); (J.H.); (K.T.)
| | - Koshiro Terawaki
- Division of Regenerative Medicine, Research Center for Medical Sciences, The Jikei University School of Medicine, Tokyo 105-8461, Japan; (H.O.); (N.-M.V.V.); (J.H.); (K.T.)
- Department of Radiological Sciences, Tokyo Metropolitan University, Tokyo 116-0012, Japan;
| | - Takako Shirakawa
- Department of Radiological Sciences, Tokyo Metropolitan University, Tokyo 116-0012, Japan;
| | - Hirotaka James Okano
- Division of Regenerative Medicine, Research Center for Medical Sciences, The Jikei University School of Medicine, Tokyo 105-8461, Japan; (H.O.); (N.-M.V.V.); (J.H.); (K.T.)
| |
Collapse
|
14
|
Clifford B, Gu Y, Liu Y, Kim K, Huang S, Li Y, Lam F, Liang ZP, Yu X. High-Resolution Dynamic 31P-MR Spectroscopic Imaging for Mapping Mitochondrial Function. IEEE Trans Biomed Eng 2020; 67:2745-2753. [PMID: 32011244 PMCID: PMC7384926 DOI: 10.1109/tbme.2020.2969892] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
OBJECTIVE To enable non-invasive dynamic metabolic mapping in rodent model studies of mitochondrial function using 31P-MR spectroscopic imaging (MRSI). METHODS We developed a novel method for high-resolution dynamic 31P-MRSI. The method synergistically integrates physics-based models of spectral structures, biochemical modeling of molecular dynamics, and subspace learning to capture spatiospectral variations. Fast data acquisition was achieved using rapid spiral trajectories and sparse sampling of (k, t, T)-space; image reconstruction was accomplished using a low-rank tensor-based framework. RESULTS The proposed method provided high-resolution dynamic metabolic mapping in rat hindlimb at spatial and temporal resolutions of 4[Formula: see text]2 mm3 and 1.28 s, respectively. This allowed for in vivo mapping of the time-constant of phosphocreatine resynthesis, a well established index of mitochondrial oxidative capacity. Multiple rounds of in vivo experiments were performed to demonstrate reproducibility, and in vitro experiments were used to validate the accuracy of the estimated metabolite maps. CONCLUSIONS A new model-based method is proposed to achieve high-resolution dynamic 31P-MRSI. The proposed method's ability to delineate metabolic heterogeneity was demonstrated in rat hindlimb. SIGNIFICANCE Abnormal mitochondrial metabolism is a key cellular dysfunction in many prevalent diseases such as diabetes and heart disease; however, current understanding of mitochondrial function is mostly gained from studies on isolated mitochondria under nonphysiological conditions. The proposed method has the potential to open new avenues of research by allowing in vivo and longitudinal studies of mitochondrial dysfunction in disease development and progression.
Collapse
Affiliation(s)
- Bryan Clifford
- Department of Electrical and Computer Engineering and the Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign
| | - Yuning Gu
- Department of Biomedical Engineering and the Case Center for Imaging Research, Case Western Reserve University
| | - Yuchi Liu
- Department of Biomedical Engineering and the Case Center for Imaging Research, Case Western Reserve University
| | - Kihwan Kim
- Department of Biomedical Engineering and the Case Center for Imaging Research, Case Western Reserve University
| | - Sherry Huang
- Department of Biomedical Engineering and the Case Center for Imaging Research, Case Western Reserve University
| | - Yudu Li
- Department of Electrical and Computer Engineering and the Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign
| | - Fan Lam
- Department of Bioengineering and the Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign
| | - Zhi-Pei Liang
- Department of Electrical and Computer Engineering and the Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Xin Yu
- Departments of Biomedical Engineering, Radiology, and Physiology and Biophysics, as well as the Case Center for Imaging Research, Case Western Reserve University, Cleveland, OH 44106-7207 USA
| |
Collapse
|
15
|
Santos-Díaz A, Noseworthy MD. Phosphorus magnetic resonance spectroscopy and imaging (31P-MRS/MRSI) as a window to brain and muscle metabolism: A review of the methods. Biomed Signal Process Control 2020. [DOI: 10.1016/j.bspc.2020.101967] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
|
16
|
Korzowski A, Weinfurtner N, Mueller S, Breitling J, Goerke S, Schlemmer H, Ladd ME, Paech D, Bachert P. Volumetric mapping of intra‐ and extracellular pH in the human brain using
31
P MRSI at 7T. Magn Reson Med 2020; 84:1707-1723. [DOI: 10.1002/mrm.28255] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 02/19/2020] [Accepted: 02/20/2020] [Indexed: 12/31/2022]
Affiliation(s)
- Andreas Korzowski
- Division of Medical Physics in Radiology German Cancer Research Center (DKFZ) Heidelberg Germany
| | - Nina Weinfurtner
- Division of Radiology German Cancer Research Center (DKFZ) Heidelberg Germany
| | - Sebastian Mueller
- Division of Medical Physics in Radiology German Cancer Research Center (DKFZ) Heidelberg Germany
| | - Johannes Breitling
- Division of Medical Physics in Radiology German Cancer Research Center (DKFZ) Heidelberg Germany
- Max‐Planck‐Institute for Nuclear Physics Heidelberg Germany
- Faculty of Physics and Astronomy University of Heidelberg Heidelberg Germany
| | - Steffen Goerke
- Division of Medical Physics in Radiology German Cancer Research Center (DKFZ) Heidelberg Germany
| | | | - Mark E. Ladd
- Division of Medical Physics in Radiology German Cancer Research Center (DKFZ) Heidelberg Germany
- Faculty of Physics and Astronomy University of Heidelberg Heidelberg Germany
- Faculty of Medicine University of Heidelberg Heidelberg Germany
| | - Daniel Paech
- Division of Radiology German Cancer Research Center (DKFZ) Heidelberg Germany
| | - Peter Bachert
- Division of Medical Physics in Radiology German Cancer Research Center (DKFZ) Heidelberg Germany
- Faculty of Physics and Astronomy University of Heidelberg Heidelberg Germany
| |
Collapse
|
17
|
Chen L, Schär M, Chan KWY, Huang J, Wei Z, Lu H, Qin Q, Weiss RG, van Zijl PCM, Xu J. In vivo imaging of phosphocreatine with artificial neural networks. Nat Commun 2020; 11:1072. [PMID: 32102999 PMCID: PMC7044432 DOI: 10.1038/s41467-020-14874-0] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 02/10/2020] [Indexed: 12/01/2022] Open
Abstract
Phosphocreatine (PCr) plays a vital role in neuron and myocyte energy homeostasis. Currently, there are no routine diagnostic tests to noninvasively map PCr distribution with clinically relevant spatial resolution and scan time. Here, we demonstrate that artificial neural network-based chemical exchange saturation transfer (ANNCEST) can be used to rapidly quantify PCr concentration with robust immunity to commonly seen MRI interferences. High-quality PCr mapping of human skeletal muscle, as well as the information of exchange rate, magnetic field and radio-frequency transmission inhomogeneities, can be obtained within 1.5 min on a 3 T standard MRI scanner using ANNCEST. For further validation, we apply ANNCEST to measure the PCr concentrations in exercised skeletal muscle. The ANNCEST outcomes strongly correlate with those from 31P magnetic resonance spectroscopy (R = 0.813, p < 0.001, t test). These results suggest that ANNCEST has potential as a cost-effective and widely available method for measuring PCr and diagnosing related diseases.
Collapse
Affiliation(s)
- Lin Chen
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Michael Schär
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Kannie W Y Chan
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, China
| | - Jianpan Huang
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, China
| | - Zhiliang Wei
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Hanzhang Lu
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Qin Qin
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Robert G Weiss
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Peter C M van Zijl
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jiadi Xu
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA.
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| |
Collapse
|
18
|
Niess F, Schmid AI, Bogner W, Wolzt M, Carlier P, Trattnig S, Moser E, Meyerspeer M. Interleaved 31 P MRS/ 1 H ASL for analysis of metabolic and functional heterogeneity along human lower leg muscles at 7T. Magn Reson Med 2019; 83:1909-1919. [PMID: 31846116 PMCID: PMC7065182 DOI: 10.1002/mrm.28088] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 10/16/2019] [Accepted: 10/28/2019] [Indexed: 12/16/2022]
Abstract
PURPOSE MR offers the unique possibility to noninvasively investigate cellular energy metabolism via 31P MRS, while blood perfusion, which provides oxygen and substrates to the tissue, is accessible by arterial spin labeling (ASL) 1H MRI. Because metabolic and hemodynamic parameters are linked, it would be desirable to study them simultaneously. A 3D-resolved method is presented that allows such measurements with high spatiotemporal resolution and has the potential to discern differences along an exercising muscle. METHODS Multi-voxel localized 31 P MRS was temporally interleaved with multi-slice pASL 1H MRI. Phosphorus spectra were collected from two adjacent positions in gastrocnemius medialis (GM) during rest, submaximal plantar flexion exercise and recovery, while perfusion and T 2 * -weighted axial images were acquired at the same time. Seventeen healthy volunteers (9 f / 8 m) were studied at 7 T. RESULTS An increase of postexercise perfusion and T 2 * -weighted signal in GM positively correlated with end-exercise PCr depletion and pH drop. At proximal positions functional and metabolic activity was higher than distally, that is, perfusion increase and peak T 2 * -weighted signal, end-exercise PCr depletion, end-exercise pH, and PCr recovery time constant were significantly different. An NOE-induced SNR increase of approximately 20 % (P < .001), at rest, was found in interleaved 31 P spectra, when comparing to 31 P-only acquisitions. CONCLUSIONS A technique for fast, simultaneous imaging of muscle functional heterogeneity in ASL, T 2 * and acquisition of time-resolved 31 P MRS data is presented. These single exercise recovery experiments can be used to investigate local variations during disease progression in patients suffering from vascular or muscular diseases.
Collapse
Affiliation(s)
- Fabian Niess
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,High Field MR Center, Medical University of Vienna, Vienna, Austria
| | - Albrecht Ingo Schmid
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,High Field MR Center, Medical University of Vienna, Vienna, Austria
| | - Wolfgang Bogner
- High Field MR Center, Medical University of Vienna, Vienna, Austria.,Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Michael Wolzt
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | | | - Siegfried Trattnig
- High Field MR Center, Medical University of Vienna, Vienna, Austria.,Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Ewald Moser
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,High Field MR Center, Medical University of Vienna, Vienna, Austria
| | - Martin Meyerspeer
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,High Field MR Center, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
19
|
Juras V, Mlynarik V, Szomolanyi P, Valkovič L, Trattnig S. Magnetic Resonance Imaging of the Musculoskeletal System at 7T: Morphological Imaging and Beyond. Top Magn Reson Imaging 2019; 28:125-135. [PMID: 30951006 PMCID: PMC6565434 DOI: 10.1097/rmr.0000000000000205] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In 2017, a whole-body 7T magnetic resonance imaging (MRI) device was given regulatory approval for clinical use in both the EU and United States for neuro and musculoskeletal applications. As 7 Tesla allows for higher signal-to-noise , which results in higher resolution images than those obtained on lower-field-strength scanners, it has attracted considerable attention from the musculoskeletal field, as evidenced by the increasing number of publications in the last decade. Besides morphological imaging, the quantitative MR methods, such as T2, T2∗, T1ρ mapping, sodium imaging, chemical-exchange saturation transfer, and spectroscopy, substantially benefit from ultrahigh field scanning. In this review, we provide technical considerations for the individual techniques and an overview of (mostly) clinical applications for the assessment of cartilage, tendon, meniscus, and muscle. The first part of the review is dedicated to morphological applications at 7T, and the second part describes the most recent developments in quantitative MRI at 7T.
Collapse
Affiliation(s)
- Vladimir Juras
- High-field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria.,Department of Imaging Methods, Institute of Measurements Science, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Vladimir Mlynarik
- High-field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria.,Karl Landsteiner Society, St. Pölten, Austria
| | - Pavol Szomolanyi
- High-field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria.,Department of Imaging Methods, Institute of Measurements Science, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Ladislav Valkovič
- High-field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria.,Oxford Centre for Clinical Magnetic Resonance Research, BHF Centre of Research Excellence, University of Oxford, Oxford, UK.,Department of Imaging Methods, Institute of Measurements Science, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Siegfried Trattnig
- High-field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria.,Austrian Cluster for Tissue Regeneration, Vienna, Austria.,Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna, Austria
| |
Collapse
|
20
|
Sedivy P, Dezortova M, Rydlo J, Drobny M, Krssak M, Valkovic L, Hajek M. MR compatible ergometers for dynamic 31P MRS. J Appl Biomed 2019; 17:91-98. [PMID: 34907736 DOI: 10.32725/jab.2019.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 04/15/2019] [Indexed: 11/05/2022] Open
Abstract
Magnetic Resonance (MR) compatible ergometers are specialized ergometers used inside the MR scanners for the characterization of tissue metabolism changes during physical stress. They are most commonly used for dynamic phosphorous magnetic resonance spectroscopy (31P MRS), but can also be used for lactate production measurements, perfusion studies using arterial spin labelling or muscle oxygenation measurements by blood oxygen dependent contrast sequences. We will primarily discuss the importance of ergometers in the context of dynamic 31P MRS. Dynamic 31P MRS can monitor muscle fatigue and energy reserve during muscle contractions as well as the dynamics of recuperation of skeletal muscle tissue during the following recovery through signal changes of phosphocreatine (PCr), inorganic phosphate and adenosine triphosphate (ATP). Based on the measured data it is possible to calculate intracellular pH, metabolic flux of ATP through creatine-kinase reaction, anaerobic glycolysis and oxidative phosphorylation and other metabolic parameters as mitochondrial capacity. This review primarily focuses on describing various technical designs of MR compatible ergometers for dynamic 31P MRS that must be constructed with respect to the presence of magnetic field. It is also expected that the construction of ergometers will be easy for the handling and well accepted by examined subjects.
Collapse
Affiliation(s)
- Petr Sedivy
- Institute for Clinical and Experimental Medicine, Department of Diagnostic and Interventional Radiology, MR-unit, Prague, Czech Republic
| | - Monika Dezortova
- Institute for Clinical and Experimental Medicine, Department of Diagnostic and Interventional Radiology, MR-unit, Prague, Czech Republic
| | - Jan Rydlo
- Institute for Clinical and Experimental Medicine, Department of Diagnostic and Interventional Radiology, MR-unit, Prague, Czech Republic
| | - Miloslav Drobny
- Institute for Clinical and Experimental Medicine, Department of Diagnostic and Interventional Radiology, MR-unit, Prague, Czech Republic
| | - Martin Krssak
- Medical University of Vienna, Department of Internal Medicine III & High Field MR Centre, Division of Endocrinology and Metabolism, Department of Biomedical Imaging and Image guided Therapy, Vienna, Austria.,Christian Doppler Laboratory for Clinical Molecular MR Imaging (MOLIMA), Vienna, Austria
| | - Ladislav Valkovic
- University of Oxford, RDM Cardiovascular Medicine, Oxford Centre for Clinical MR Research (OCMR), Oxford, United Kingdom.,Slovak Academy of Sciences, Institute of Measurement Science, Department of Imaging Methods, Bratislava, Slovakia
| | - Milan Hajek
- Institute for Clinical and Experimental Medicine, Department of Diagnostic and Interventional Radiology, MR-unit, Prague, Czech Republic
| |
Collapse
|
21
|
Santos-Díaz A, Noseworthy MD. Comparison of compressed sensing reconstruction algorithms for 31P magnetic resonance spectroscopic imaging. Magn Reson Imaging 2019; 59:88-96. [PMID: 30853562 DOI: 10.1016/j.mri.2019.03.006] [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: 10/12/2018] [Revised: 02/28/2019] [Accepted: 03/04/2019] [Indexed: 02/01/2023]
Abstract
Phosphorus MR spectroscopy and spectroscopic imaging (31P-MRS/MRSI) provide information about energy metabolism, membrane degradation and pH in vivo. In spite of their proven utility, 31P-MRS/MRSI are not often used primarily because of the challenges imposed by the low sensitivity and low concentration of metabolites leading to low signal to noise ratio (SNR), coarse spatial resolution and prolonged acquisition time. More recently there has been considerable interest in compressed sensing as an acceleration method for MR signal acquisition. This approach takes advantage of the intrinsic sparsity of the spectral data. In this work, we present a 31P-MRSI sequence that combines a flyback EPSI trajectory and compressed sensing, and we compared two different reconstruction methods, L1 norm minimization and low rank Hankel matrix completion. Our phantom results showed good preservation of spectral quality for both ×2.0 and ×3.0 acceleration factors, using both CS reconstruction methods. However, in vivo 31P-MRS brain data showed the low rank reconstruction approach was most suitable. Overall, this study shows the feasibility of combining a flyback EPSI trajectory and compressed sensing in the acquisition of 31P-MRSI as well as the better suitability of a low rank reconstruction approach.
Collapse
Affiliation(s)
- Alejandro Santos-Díaz
- School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada; Imaging Research Center, St. Joseph's Healthcare, Hamilton, Ontario, Canada
| | - Michael D Noseworthy
- School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada; Imaging Research Center, St. Joseph's Healthcare, Hamilton, Ontario, Canada; Electrical and Computing Engineering, McMaster University, Hamilton, Ontario, Canada.
| |
Collapse
|
22
|
Santos-Díaz A, Harasym D, Noseworthy MD. Dynamic 31 P spectroscopic imaging of skeletal muscles combining flyback echo-planar spectroscopic imaging and compressed sensing. Magn Reson Med 2019; 81:3453-3461. [PMID: 30737840 DOI: 10.1002/mrm.27682] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 01/09/2019] [Accepted: 01/10/2019] [Indexed: 01/21/2023]
Abstract
PURPOSE Dynamic phosphorus MR spectroscopic imaging (31 P-MRSI) experiments require temporal resolution on the order of seconds to concurrently assess different muscle groups. A highly accelerated pulse sequence combining flyback echo-planar spectroscopic imaging (EPSI) and compressed sensing was developed and tested in a phantom and healthy humans during an exercise-recovery challenge of the lower leg muscles, using a clinical 3T MRI. METHODS A flyback EPSI readout designed to achieve 2.25 × 2.25 cm2 resolution over a 18 × 18 cm2 field of view (i.e., 8 × 8 matrix) was combined with compressed sensing through the inclusion of pseudorandom gradient blips to sub-sample the ky-kt dimensions by a factor of 2.7×, achieving a temporal resolution of 9 s. The sequence was first tested in a phantom to assess performance compared to fully sampled EPSI (fidEPSI) and phase encoded chemical shift imaging (fidCSI). Then, tests were performed in 11 healthy volunteers during an exercise-recovery challenge of the lower leg muscles. Voxels containing tissue from different muscle groups were evaluated measuring percentage phosphocreatine (%PCr) depletion, time constant of PCr recovery (τPCr) and intracellular pH at rest and following exercise. RESULTS The sequence was capable to track the dynamic PCr response of multiple muscles simultaneously. No statistical differences were found in the metabolite ratio, pH or linewidth when compared with fidEPSI and fidCSI in the phantom study. Dynamic experiments showed differences in PCr depletion when comparing soleus with gastrocnemius muscles. Intracellular pH, τPCr and %PCr decrease were consistent with reported values. CONCLUSION Highly accelerated 31 P-MRSI combining flyback EPSI and compressed sensing is capable of assessing concurrent energy metabolism in multiple muscle groups using a clinical 3T MR system.
Collapse
Affiliation(s)
- Alejandro Santos-Díaz
- School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada.,Imaging Research Center, St. Joseph's Healthcare, Hamilton, Ontario, Canada
| | - Diana Harasym
- School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada.,Imaging Research Center, St. Joseph's Healthcare, Hamilton, Ontario, Canada
| | - Michael D Noseworthy
- School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada.,Imaging Research Center, St. Joseph's Healthcare, Hamilton, Ontario, Canada.,Electrical and Computing Engineering, McMaster University, Hamilton, Ontario, Canada
| |
Collapse
|
23
|
Ladd ME, Bachert P, Meyerspeer M, Moser E, Nagel AM, Norris DG, Schmitter S, Speck O, Straub S, Zaiss M. Pros and cons of ultra-high-field MRI/MRS for human application. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2018; 109:1-50. [PMID: 30527132 DOI: 10.1016/j.pnmrs.2018.06.001] [Citation(s) in RCA: 264] [Impact Index Per Article: 44.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 06/06/2018] [Accepted: 06/07/2018] [Indexed: 05/08/2023]
Abstract
Magnetic resonance imaging and spectroscopic techniques are widely used in humans both for clinical diagnostic applications and in basic research areas such as cognitive neuroimaging. In recent years, new human MR systems have become available operating at static magnetic fields of 7 T or higher (≥300 MHz proton frequency). Imaging human-sized objects at such high frequencies presents several challenges including non-uniform radiofrequency fields, enhanced susceptibility artifacts, and higher radiofrequency energy deposition in the tissue. On the other side of the scale are gains in signal-to-noise or contrast-to-noise ratio that allow finer structures to be visualized and smaller physiological effects to be detected. This review presents an overview of some of the latest methodological developments in human ultra-high field MRI/MRS as well as associated clinical and scientific applications. Emphasis is given to techniques that particularly benefit from the changing physical characteristics at high magnetic fields, including susceptibility-weighted imaging and phase-contrast techniques, imaging with X-nuclei, MR spectroscopy, CEST imaging, as well as functional MRI. In addition, more general methodological developments such as parallel transmission and motion correction will be discussed that are required to leverage the full potential of higher magnetic fields, and an overview of relevant physiological considerations of human high magnetic field exposure is provided.
Collapse
Affiliation(s)
- Mark E Ladd
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Faculty of Medicine, University of Heidelberg, Heidelberg, Germany; Faculty of Physics and Astronomy, University of Heidelberg, Heidelberg, Germany; Erwin L. Hahn Institute for MRI, University of Duisburg-Essen, Essen, Germany.
| | - Peter Bachert
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Faculty of Physics and Astronomy, University of Heidelberg, Heidelberg, Germany.
| | - Martin Meyerspeer
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria; MR Center of Excellence, Medical University of Vienna, Vienna, Austria.
| | - Ewald Moser
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria; MR Center of Excellence, Medical University of Vienna, Vienna, Austria.
| | - Armin M Nagel
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany.
| | - David G Norris
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, Netherlands; Erwin L. Hahn Institute for MRI, University of Duisburg-Essen, Essen, Germany.
| | - Sebastian Schmitter
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany.
| | - Oliver Speck
- Department of Biomedical Magnetic Resonance, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; German Center for Neurodegenerative Diseases, Magdeburg, Germany; Center for Behavioural Brain Sciences, Magdeburg, Germany; Leibniz Institute for Neurobiology, Magdeburg, Germany.
| | - Sina Straub
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany.
| | - Moritz Zaiss
- High-Field Magnetic Resonance Center, Max-Planck-Institute for Biological Cybernetics, Tübingen, Germany.
| |
Collapse
|
24
|
Niess F, Fiedler GB, Schmid AI, Laistler E, Frass‐Kriegl R, Wolzt M, Moser E, Meyerspeer M. Dynamic multivoxel-localized 31 P MRS during plantar flexion exercise with variable knee angle. NMR IN BIOMEDICINE 2018; 31:e3905. [PMID: 29578260 PMCID: PMC6001778 DOI: 10.1002/nbm.3905] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 01/08/2018] [Accepted: 01/16/2018] [Indexed: 05/07/2023]
Abstract
Exercise studies investigating the metabolic response of calf muscles using 31 P MRS are usually performed with a single knee angle. However, during natural movement, the distribution of workload between the main contributors to force, gastrocnemius and soleus is influenced by the knee angle. Hence, it is of interest to measure the respective metabolic response of these muscles to exercise as a function of knee angle using localized spectroscopy. Time-resolved multivoxel 31 P MRS at 7 T was performed simultaneously in gastrocnemius medialis and soleus during rest, plantar flexion exercise and recovery in 12 healthy volunteers. This experiment was conducted with four different knee angles. PCr depletions correlated negatively with knee angle in gastrocnemius medialis, decreasing from 79±14 % (extended leg) to 35±23 %(∼40°), and positively in soleus, increasing from 20±21 % to 36±25 %; differences were significant. Linear correlations were found between knee angle and end-exercise PCr depletions in gastrocnemius medialis (R2 =0.8) and soleus (R2 =0.53). PCr recovery times and end-exercise pH changes that correlated with PCr depletion were consistent with the literature in gastrocnemius medialis and differences between knee angles were significant. These effects were less pronounced in soleus and not significant for comparable PCr depletions. Maximum oxidative capacity calculated for all knee angles was in excellent agreement with the literature and showed no significant changes between different knee angles. In conclusion, these findings confirm that plantar flexion exercise with a straight leg is a suitable paradigm, when data are acquired from gastrocnemius only (using either localized MRS or small surface coils), and that activation of soleus requires the knee to be flexed. The present study comprises a systematic investigation of the effects of the knee angle on metabolic parameters, measured with dynamic multivoxel 31 P MRS during muscle exercise and recovery, and the findings should be used in future study design.
Collapse
Affiliation(s)
- Fabian Niess
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaAustria
- Highfield MR CenterMedical University of ViennaAustria
| | - Georg B. Fiedler
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaAustria
- Highfield MR CenterMedical University of ViennaAustria
| | - Albrecht I. Schmid
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaAustria
- Highfield MR CenterMedical University of ViennaAustria
| | - Elmar Laistler
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaAustria
- Highfield MR CenterMedical University of ViennaAustria
| | - Roberta Frass‐Kriegl
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaAustria
- Highfield MR CenterMedical University of ViennaAustria
| | - Michael Wolzt
- Department of Clinical PharmacologyMedical University of ViennaAustria
| | - Ewald Moser
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaAustria
- Highfield MR CenterMedical University of ViennaAustria
| | - Martin Meyerspeer
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaAustria
- Highfield MR CenterMedical University of ViennaAustria
| |
Collapse
|
25
|
Boss A, Heskamp L, Breukels V, Bains LJ, van Uden MJ, Heerschap A. Oxidative capacity varies along the length of healthy human tibialis anterior. J Physiol 2018; 596:1467-1483. [PMID: 29455454 DOI: 10.1113/jp275009] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 02/12/2018] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS During exercise skeletal muscles use the energy buffer phosphocreatine. The post-exercise recovery of phosphocreatine is a measure of the oxidative capacity of muscles and is traditionally assessed by 31 P magnetic resonance spectroscopy of a large tissue region, assuming homogeneous energy metabolism. To test this assumption, we collected spatially resolved spectra along the length of human tibialis anterior using a home-built array of 31 P detection coils, and observed a striking gradient in the recovery rate of phosphocreatine, decreasing along the proximo-distal axis of the muscle. A similar gradient along this muscle was observed in signal changes recorded by 1 H muscle functional MRI. These findings identify intra-muscular variation in the physiology of muscles in action and highlight the importance of localized sampling for any methodology investigating oxidative metabolism of this, and potentially other muscles. ABSTRACT The rate of phosphocreatine (PCr) recovery (kPCr ) after exercise, characterizing muscle oxidative capacity, is traditionally assessed with unlocalized 31 P magnetic resonance spectroscopy (MRS) using a single surface coil. However, because of intramuscular variation in fibre type and oxygen supply, kPCr may be non-uniform within muscles. We tested this along the length of the tibialis anterior (TA) muscle in 10 male volunteers. For this purpose, we employed a 3T MR system with a 31 P/1 H volume transmit coil combined with a home-built 31 P phased-array receive probe, consisting of five coil elements covering the TA muscle length. Mono-exponential kPCr was determined for all coil elements after 40 s of submaximal isometric dorsiflexion (SUBMAX) and incremental exercise to exhaustion (EXH). In addition, muscle functional MRI (1 H mfMRI) was performed using the volume coil after another 40 s of SUBMAX. A strong gradient in kPCr was observed along the TA (P < 0.001), being two times higher proximally vs. distally during SUBMAX and EXH. Statistical analysis showed that this gradient cannot be explained by pH variations. A similar gradient was seen in the slope of the initial post-exercise 1 H mfMRI signal change, which was higher proximally than distally in both the TA and the extensor digitorum longus (P < 0.001) and strongly correlated with kPCr . The pronounced differences along the TA in functional oxidative capacity identify regional variation in the physiological demand of this muscle during everyday activities and have implications for the bio-energetic assessment of interventions to modify its performance and of neuromuscular disorders involving the TA.
Collapse
Affiliation(s)
- Andreas Boss
- Department of Radiology and Nuclear Medicine, Radboud university medical center, Nijmegen, The Netherlands
| | - Linda Heskamp
- Department of Radiology and Nuclear Medicine, Radboud university medical center, Nijmegen, The Netherlands
| | - Vincent Breukels
- Department of Radiology and Nuclear Medicine, Radboud university medical center, Nijmegen, The Netherlands
| | - Lauren J Bains
- Donders Centre for Cognitive Neuroimaging, Radboud University, Nijmegen, The Netherlands
| | - Mark J van Uden
- Department of Radiology and Nuclear Medicine, Radboud university medical center, Nijmegen, The Netherlands
| | - Arend Heerschap
- Department of Radiology and Nuclear Medicine, Radboud university medical center, Nijmegen, The Netherlands
| |
Collapse
|
26
|
Santos-Díaz A, Obruchkov SI, Schulte RF, Noseworthy MD. Phosphorus magnetic resonance spectroscopic imaging using flyback echo planar readout trajectories. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2018; 31:553-564. [PMID: 29383517 DOI: 10.1007/s10334-018-0675-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 01/09/2018] [Accepted: 01/09/2018] [Indexed: 01/07/2023]
Abstract
OBJECT To present and evaluate a fast phosphorus magnetic resonance spectroscopic imaging (MRSI) sequence using echo planar spectroscopic imaging with flyback readout gradient trajectories. MATERIALS AND METHODS Waveforms were designed and implemented using a 3 Tesla MRI system. 31P spectra were acquired with 2 × 2 cm2 and 3 × 3 cm2 resolution over a 20- and 21-cm field of view and spectral bandwidths up to 1923 Hz. The sequence was first tested using a 20-cm-diameter phosphate phantom, and subsequent in vivo tests were performed on healthy human calf muscles and brains from five volunteers. RESULTS Flyback EPSI achieved 10× and 7× reductions in acquisition time, with 68.0 ± 1.2 and 69.8 ± 2.2% signal-to-noise ratio (SNR) per unit of time efficiency (theoretical SNR efficiency was 74.5 and 76.4%) for the in vivo experiments, compared to conventional phase-encoded MRSI for the 2 × 2 cm2 and 3 × 3 cm2 resolution waveforms, respectively. Statistical analysis showed no difference in the quantification of most metabolites. Time savings and SNR comparisons were consistent across phantom, leg and brain experiments. CONCLUSION EPSI using flyback readout trajectories was found to be a reliable alternative for acquiring 31P-MRSI data in a shorter acquisition time.
Collapse
Affiliation(s)
- Alejandro Santos-Díaz
- School of Biomedical Engineering, McMaster University, Hamilton, ON, Canada.,Imaging Research Center, St. Joseph's Healthcare, Hamilton, ON, Canada
| | - Sergei I Obruchkov
- Robinson Research Institute, Victoria University of Wellington, Wellington, New Zealand
| | | | - Michael D Noseworthy
- School of Biomedical Engineering, McMaster University, Hamilton, ON, Canada. .,Imaging Research Center, St. Joseph's Healthcare, Hamilton, ON, Canada. .,Department of Electrical and Computer Engineering, McMaster University, Engineering Technology Building, ETB-406, 1280 Main St. West, Hamilton, ON, L8S 4K1, Canada.
| |
Collapse
|
27
|
Chiew M, Jiang W, Burns B, Larson P, Steel A, Jezzard P, Albert Thomas M, Emir UE. Density-weighted concentric rings k-space trajectory for 1 H magnetic resonance spectroscopic imaging at 7 T. NMR IN BIOMEDICINE 2018; 31:e3838. [PMID: 29044762 PMCID: PMC5969060 DOI: 10.1002/nbm.3838] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 08/31/2017] [Accepted: 09/05/2017] [Indexed: 05/21/2023]
Abstract
It has been shown that density-weighted (DW) k-space sampling with spiral and conventional phase encoding trajectories reduces spatial side lobes in magnetic resonance spectroscopic imaging (MRSI). In this study, we propose a new concentric ring trajectory (CRT) for DW-MRSI that samples k-space with a density that is proportional to a spatial, isotropic Hanning window. The properties of two different DW-CRTs were compared against a radially equidistant (RE) CRT and an echo-planar spectroscopic imaging (EPSI) trajectory in simulations, phantoms and in vivo experiments. These experiments, conducted at 7 T with a fixed nominal voxel size and matched acquisition times, revealed that the two DW-CRT designs improved the shape of the spatial response function by suppressing side lobes, also resulting in improved signal-to-noise ratio (SNR). High-quality spectra were acquired for all trajectories from a specific region of interest in the motor cortex with an in-plane resolution of 7.5 × 7.5 mm2 in 8 min 3 s. Due to hardware limitations, high-spatial-resolution spectra with an in-plane resolution of 5 × 5 mm2 and an acquisition time of 12 min 48 s were acquired only for the RE and one of the DW-CRT trajectories and not for EPSI. For all phantom and in vivo experiments, DW-CRTs resulted in the highest SNR. The achieved in vivo spectral quality of the DW-CRT method allowed for reliable metabolic mapping of eight metabolites including N-acetylaspartylglutamate, γ-aminobutyric acid and glutathione with Cramér-Rao lower bounds below 50%, using an LCModel analysis. Finally, high-quality metabolic mapping of a whole brain slice using DW-CRT was achieved with a high in-plane resolution of 5 × 5 mm2 in a healthy subject. These findings demonstrate that our DW-CRT MRSI technique can perform robustly on MRI systems and within a clinically feasible acquisition time.
Collapse
Affiliation(s)
- Mark Chiew
- Wellcome Centre for Integrative Neuroimaging, FMRIB Division, Nuffield Department of Clinical NeurosciencesUniversity of OxfordJohn Radcliffe HospitalOxfordUK
| | - Wenwen Jiang
- Department of Radiology and Biomedical ImagingUniversity of CaliforniaSan FranciscoCAUSA
| | - Brian Burns
- Department of OncologyUniversity of OxfordOxfordUK
| | - Peder Larson
- Department of Radiology and Biomedical ImagingUniversity of CaliforniaSan FranciscoCAUSA
| | - Adam Steel
- Wellcome Centre for Integrative Neuroimaging, FMRIB Division, Nuffield Department of Clinical NeurosciencesUniversity of OxfordJohn Radcliffe HospitalOxfordUK
- Laboratory of Brain and Cognition, National Institute of Mental HealthNational Institutes of HealthBethesdaMDUSA
| | - Peter Jezzard
- Wellcome Centre for Integrative Neuroimaging, FMRIB Division, Nuffield Department of Clinical NeurosciencesUniversity of OxfordJohn Radcliffe HospitalOxfordUK
| | - M. Albert Thomas
- Department of Radiological SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - Uzay E. Emir
- Wellcome Centre for Integrative Neuroimaging, FMRIB Division, Nuffield Department of Clinical NeurosciencesUniversity of OxfordJohn Radcliffe HospitalOxfordUK
- School of Health SciencesPurdue UniversityWest LafayetteINUSA
| |
Collapse
|
28
|
Mancuso M, McFarland R, Klopstock T, Hirano M. International Workshop:: Outcome measures and clinical trial readiness in primary mitochondrial myopathies in children and adults. Consensus recommendations. 16-18 November 2016, Rome, Italy. Neuromuscul Disord 2017; 27:1126-1137. [PMID: 29074296 PMCID: PMC6094160 DOI: 10.1016/j.nmd.2017.08.006] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 08/24/2017] [Accepted: 08/30/2017] [Indexed: 01/01/2023]
Affiliation(s)
- Michelangelo Mancuso
- Department of Experimental and Clinical Medicine, Neurological Institute, University of Pisa, Italy.
| | - Robert McFarland
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Department of Physiology and Functional Genomics NE1 3BZ, Newcastle University, Newcastle upon Tyne, UK
| | - Thomas Klopstock
- Friedrich-Baur-Institut an der Neurologischen Klinik und Poliklinik, LMU München, Ziemssenstr. 1a, 80336 München, Federal Republic of Germany
| | - Michio Hirano
- Department of Neurology, H. Houston Merritt Neuromuscular Research Center, Columbia University Medical Center, New York, NY, USA
| |
Collapse
|
29
|
Liu Y, Gu Y, Yu X. Assessing tissue metabolism by phosphorous-31 magnetic resonance spectroscopy and imaging: a methodology review. Quant Imaging Med Surg 2017; 7:707-726. [PMID: 29312876 PMCID: PMC5756783 DOI: 10.21037/qims.2017.11.03] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 11/11/2017] [Indexed: 01/11/2023]
Abstract
Many human diseases are caused by an imbalance between energy production and demand. Magnetic resonance spectroscopy (MRS) and magnetic resonance imaging (MRI) provide the unique opportunity for in vivo assessment of several fundamental events in tissue metabolism without the use of ionizing radiation. Of particular interest, phosphate metabolites that are involved in ATP generation and utilization can be quantified noninvasively by phosphorous-31 (31P) MRS/MRI. Furthermore, 31P magnetization transfer (MT) techniques allow in vivo measurement of metabolic fluxes via creatine kinase (CK) and ATP synthase. However, a major impediment for the clinical applications of 31P-MRS/MRI is the prohibitively long acquisition time and/or the low spatial resolution that are necessary to achieve adequate signal-to-noise ratio. In this review, current 31P-MRS/MRI techniques used in basic science and clinical research are presented. Recent advances in the development of fast 31P-MRS/MRI methods are also discussed.
Collapse
Affiliation(s)
- Yuchi Liu
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Yuning Gu
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Xin Yu
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
- Department of Radiology, Case Western Reserve University, Cleveland, OH, USA
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH, USA
- Case Center for Imaging Research, Case Western Reserve University, Cleveland, OH, USA
| |
Collapse
|
30
|
Purvis LAB, Clarke WT, Biasiolli L, Valkovič L, Robson MD, Rodgers CT. OXSA: An open-source magnetic resonance spectroscopy analysis toolbox in MATLAB. PLoS One 2017; 12:e0185356. [PMID: 28938003 PMCID: PMC5609763 DOI: 10.1371/journal.pone.0185356] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 09/11/2017] [Indexed: 01/17/2023] Open
Abstract
In vivo magnetic resonance spectroscopy provides insight into metabolism in the human body. New acquisition protocols are often proposed to improve the quality or efficiency of data collection. Processing pipelines must also be developed to use these data optimally. Current fitting software is either targeted at general spectroscopy fitting, or for specific protocols. We therefore introduce the MATLAB-based OXford Spectroscopy Analysis (OXSA) toolbox to allow researchers to rapidly develop their own customised processing pipelines. The toolbox aims to simplify development by: being easy to install and use; seamlessly importing Siemens Digital Imaging and Communications in Medicine (DICOM) standard data; allowing visualisation of spectroscopy data; offering a robust fitting routine; flexibly specifying prior knowledge when fitting; and allowing batch processing of spectra. This article demonstrates how each of these criteria have been fulfilled, and gives technical details about the implementation in MATLAB. The code is freely available to download from https://github.com/oxsatoolbox/oxsa.
Collapse
Affiliation(s)
- Lucian A. B. Purvis
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
- * E-mail:
| | - William T. Clarke
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Luca Biasiolli
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Ladislav Valkovič
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
- Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Matthew D. Robson
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Christopher T. Rodgers
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| |
Collapse
|
31
|
Baligand C, Todd AG, Lee-McMullen B, Vohra RS, Byrne BJ, Falk DJ, Walter GA. 13C/ 31P MRS Metabolic Biomarkers of Disease Progression and Response to AAV Delivery of hGAA in a Mouse Model of Pompe Disease. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2017; 7:42-49. [PMID: 29018835 PMCID: PMC5626920 DOI: 10.1016/j.omtm.2017.09.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 09/05/2017] [Indexed: 01/31/2023]
Abstract
The development of therapeutic clinical trials for glycogen storage disorders, including Pompe disease, has called for non-invasive and objective biomarkers. Glycogen accumulation can be measured in vivo with 13C MRS. However, clinical implementation remains challenging due to low signal-to-noise. On the other hand, the buildup of glycolytic intermediates may be detected with 31P MRS. We sought to identify new biomarkers of disease progression in muscle using 13C/31P MRS and 1H HR-MAS in a mouse model of Pompe disease (Gaa−/−). We evaluated the sensitivity of these MR biomarkers in vivo after treatment using an adeno-associated virus vector 2/9 encoding hGAA driven by the desmin promotor. 31P MRS showed significantly elevated phosphomonoesters (PMEs) in Gaa−/− compared to control at 2 (0.06 ± 0.02 versus 0.03 ± 0.01; p = 0.003), 6, 12, and 18 months of age. Correlative 1H HR-MAS measures in intact gastrocnemius muscles revealed high glucose-6-phosphate (G-6-P). After intramuscular AAV injections, glycogen, PME, and G-6-P were decreased within normal range. The changes in PME levels likely partly resulted from changes in G-6-P, one of the overlapping phosphomonoesters in the 31P MR spectra in vivo. Because 31P MRS is inherently more sensitive than 13C MRS, PME levels have greater potential as a clinical biomarker and should be considered as a complementary approach for future studies in Pompe patients.
Collapse
Affiliation(s)
- Celine Baligand
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, FL 32610, USA
| | - Adrian G Todd
- Department of Pediatrics, University of Florida, Gainesville, FL 32610, USA
| | - Brittany Lee-McMullen
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, FL 32610, USA
| | - Ravneet S Vohra
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, FL 32610, USA
| | - Barry J Byrne
- Department of Pediatrics, University of Florida, Gainesville, FL 32610, USA
| | - Darin J Falk
- Department of Pediatrics, University of Florida, Gainesville, FL 32610, USA
| | - Glenn A Walter
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, FL 32610, USA
| |
Collapse
|
32
|
Khegai O, Madelin G, Brown R, Parasoglou P. Dynamic phosphocreatine imaging with unlocalized pH assessment of the human lower leg muscle following exercise at 3T. Magn Reson Med 2017; 79:974-980. [PMID: 28560829 DOI: 10.1002/mrm.26728] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 03/29/2017] [Accepted: 03/30/2017] [Indexed: 12/16/2022]
Abstract
PURPOSE To develop a high temporal resolution imaging method that measures muscle-specific phosphocreatine (PCr) resynthesis time constant (τPCr ) and pH changes in muscles of the lower leg following exercise on a clinical 3T MRI scanner. METHODS We developed a frequency-selective 3D non-Cartesian FLORET sequence to measure PCr with 17-mm nominal isotropic resolution (28 mm actual resolution) and 6-s temporal resolution to capture dynamic metabolic muscle activity. The sequence was designed to additionally collect inorganic phosphate spectra for pH quantification, which were localized using sensitivity profiles of individual coil elements. Nineteen healthy volunteers were scanned while performing a plantar flexion exercise on an in-house developed ergometer. Data were acquired with a dual-tuned multichannel coil array that enabled phosphorus imaging and proton localization for muscle segmentation. RESULTS After a 90-s plantar flexion exercise at 0.66 Hz with resistance set to 40% of the maximum voluntary contraction, τPCr was estimated at 22.9 ± 8.8 s (mean ± standard deviation) with statistical coefficient of determination r2 = 0.89 ± 0.05. The corresponding pH values after exercise were in the range of 6.9-7.1 in the gastrocnemius muscle. CONCLUSION The developed technique allows measurement of muscle-specific PCr resynthesis kinetics and pH changes following exercise, with a temporal resolution and accuracy comparable to that of single voxel 31 P-MRS sequences. Magn Reson Med 79:974-980, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
Collapse
Affiliation(s)
- Oleksandr Khegai
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, New York, USA.,Center for Advanced Imaging Innovation and Research, Department of Radiology, New York University School of Medicine, New York, New York, USA
| | - Guillaume Madelin
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, New York, USA.,Center for Advanced Imaging Innovation and Research, Department of Radiology, New York University School of Medicine, New York, New York, USA
| | - Ryan Brown
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, New York, USA.,Center for Advanced Imaging Innovation and Research, Department of Radiology, New York University School of Medicine, New York, New York, USA.,NYU WIRELESS, Polytechnic Institute of New York University, Brooklyn, New York, USA
| | - Prodromos Parasoglou
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, New York, USA.,Center for Advanced Imaging Innovation and Research, Department of Radiology, New York University School of Medicine, New York, New York, USA
| |
Collapse
|
33
|
Ma C, Clifford B, Liu Y, Gu Y, Lam F, Yu X, Liang ZP. High-resolution dynamic 31 P-MRSI using a low-rank tensor model. Magn Reson Med 2017; 78:419-428. [PMID: 28556373 DOI: 10.1002/mrm.26762] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Revised: 04/04/2017] [Accepted: 05/03/2017] [Indexed: 12/16/2022]
Abstract
PURPOSE To develop a rapid 31 P-MRSI method with high spatiospectral resolution using low-rank tensor-based data acquisition and image reconstruction. METHODS The multidimensional image function of 31 P-MRSI is represented by a low-rank tensor to capture the spatial-spectral-temporal correlations of data. A hybrid data acquisition scheme is used for sparse sampling, which consists of a set of "training" data with limited k-space coverage to capture the subspace structure of the image function, and a set of sparsely sampled "imaging" data for high-resolution image reconstruction. An explicit subspace pursuit approach is used for image reconstruction, which estimates the bases of the subspace from the "training" data and then reconstructs a high-resolution image function from the "imaging" data. RESULTS We have validated the feasibility of the proposed method using phantom and in vivo studies on a 3T whole-body scanner and a 9.4T preclinical scanner. The proposed method produced high-resolution static 31 P-MRSI images (i.e., 6.9 × 6.9 × 10 mm3 nominal resolution in a 15-min acquisition at 3T) and high-resolution, high-frame-rate dynamic 31 P-MRSI images (i.e., 1.5 × 1.5 × 1.6 mm3 nominal resolution, 30 s/frame at 9.4T). CONCLUSIONS Dynamic spatiospectral variations of 31 P-MRSI signals can be efficiently represented by a low-rank tensor. Exploiting this mathematical structure for data acquisition and image reconstruction can lead to fast 31 P-MRSI with high resolution, frame-rate, and SNR. Magn Reson Med 78:419-428, 2017. © 2017 International Society for Magnetic Resonance in Medicine.
Collapse
Affiliation(s)
- Chao Ma
- Gordon Center for Medical Imaging, NMMI, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Bryan Clifford
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.,Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Yuchi Liu
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA
| | - Yuning Gu
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA
| | - Fan Lam
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.,Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Xin Yu
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA
| | - Zhi-Pei Liang
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.,Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| |
Collapse
|
34
|
Valkovič L, Chmelík M, Krššák M. In-vivo 31P-MRS of skeletal muscle and liver: A way for non-invasive assessment of their metabolism. Anal Biochem 2017; 529:193-215. [PMID: 28119063 PMCID: PMC5478074 DOI: 10.1016/j.ab.2017.01.018] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 01/13/2017] [Accepted: 01/19/2017] [Indexed: 01/18/2023]
Abstract
In addition to direct assessment of high energy phosphorus containing metabolite content within tissues, phosphorus magnetic resonance spectroscopy (31P-MRS) provides options to measure phospholipid metabolites and cellular pH, as well as the kinetics of chemical reactions of energy metabolism in vivo. Even though the great potential of 31P-MR was recognized over 30 years ago, modern MR systems, as well as new, dedicated hardware and measurement techniques provide further opportunities for research of human biochemistry. This paper presents a methodological overview of the 31P-MR techniques that can be used for basic, physiological, or clinical research of human skeletal muscle and liver in vivo. Practical issues of 31P-MRS experiments and examples of potential applications are also provided. As signal localization is essential for liver 31P-MRS and is important for dynamic muscle examinations as well, typical localization strategies for 31P-MR are also described.
Collapse
Affiliation(s)
- Ladislav Valkovič
- High-field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria; Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, Oxford, United Kingdom; Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sciences, Bratislava, Slovakia.
| | - Marek Chmelík
- High-field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria; Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna, Austria; Institute for Clinical Molecular MRI in Musculoskeletal System, Karl Landsteiner Society, Vienna, Austria
| | - Martin Krššák
- High-field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria; Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna, Austria; Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| |
Collapse
|