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Tsampasian V, Cameron D, Sobhan R, Bazoukis G, Vassiliou VS. Phosphorus Magnetic Resonance Spectroscopy ( 31P MRS) and Cardiovascular Disease: The Importance of Energy. Medicina (B Aires) 2023; 59:medicina59010174. [PMID: 36676798 PMCID: PMC9866867 DOI: 10.3390/medicina59010174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 01/10/2023] [Accepted: 01/13/2023] [Indexed: 01/17/2023] Open
Abstract
Background and Objectives: The heart is the organ with the highest metabolic demand in the body, and it relies on high ATP turnover and efficient energy substrate utilisation in order to function normally. The derangement of myocardial energetics may lead to abnormalities in cardiac metabolism, which herald the symptoms of heart failure (HF). In addition, phosphorus magnetic resonance spectroscopy (31P MRS) is the only available non-invasive method that allows clinicians and researchers to evaluate the myocardial metabolic state in vivo. This review summarises the importance of myocardial energetics and provides a systematic review of all the available research studies utilising 31P MRS to evaluate patients with a range of cardiac pathologies. Materials and Methods: We have performed a systematic review of all available studies that used 31P MRS for the investigation of myocardial energetics in cardiovascular disease. Results: A systematic search of the Medline database, the Cochrane library, and Web of Science yielded 1092 results, out of which 62 studies were included in the systematic review. The 31P MRS has been used in numerous studies and has demonstrated that impaired myocardial energetics is often the beginning of pathological processes in several cardiac pathologies. Conclusions: The 31P MRS has become a valuable tool in the understanding of myocardial metabolic changes and their impact on the diagnosis, risk stratification, and prognosis of patients with cardiovascular diseases.
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Affiliation(s)
- Vasiliki Tsampasian
- Norwich Medical School, University of East Anglia, Bob Champion Research & Education Building, Research Park, Rosalind Franklin Rd, Norwich NR4 7UQ, UK
- Correspondence: (V.T.); (V.S.V.)
| | - Donnie Cameron
- C.J. Gorter MRI Center, Department of Radiology, Leiden University Medical Centre, 2333 ZA Leiden, The Netherlands
| | - Rashed Sobhan
- Norwich Medical School, University of East Anglia, Bob Champion Research & Education Building, Research Park, Rosalind Franklin Rd, Norwich NR4 7UQ, UK
| | - George Bazoukis
- Department of Cardiology, Larnaca General Hospital, Larnaca 6301, Cyprus
- Department of Basic and Clinical Sciences, University of Nicosia Medical School, Nicosia 2417, Cyprus
| | - Vassilios S. Vassiliou
- Norwich Medical School, University of East Anglia, Bob Champion Research & Education Building, Research Park, Rosalind Franklin Rd, Norwich NR4 7UQ, UK
- Correspondence: (V.T.); (V.S.V.)
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Papalia F, Jouhra F, Amin‐Youssef G, Shah AM, Charles‐Edwards G, Okonko DO. Cardiac energetics in patients with chronic heart failure and iron deficiency: an in-vivo 31 P magnetic resonance spectroscopy study. Eur J Heart Fail 2022; 24:716-723. [PMID: 35199406 PMCID: PMC9310591 DOI: 10.1002/ejhf.2454] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 01/25/2022] [Accepted: 02/18/2022] [Indexed: 11/12/2022] Open
Abstract
AIMS Iron deficiency (ID) is prevalent and adverse in chronic heart failure (CHF) but few human studies have explored the myocardial mechanism(s) that potentially underlie this adversity. Because mitochondrial oxidative phosphorylation (OXPHOS) provides over 90% of the hearts adenosine triphosphate (ATP), and iron is critical for OXPHOS, we hypothesized that patients with CHF and ID would harbour greater cardiac energetic impairments than patients without ID. METHODS AND RESULTS Phosphorus magnetic resonance spectroscopy was used to quantify the phosphocreatine (PCr) to ATP (PCr/ATP) ratio, an index of in-vivo cardiac energetics, in CHF patients and healthy volunteers. Cardiac structure and function was assessed from magnetic resonance short stack cines. Patients with (n = 27) and without (n = 12) ID, and healthy volunteers (n = 11), were similar with respect to age and gender. The PCr/ATP ratio was lower in patients with ID (1.03 [0.83-1.38]) compared to those without ID (1.72 [1.51-2.26], p < 0.01) and healthy volunteers (1.39 [1.10-3.68], p < 0.05). This was despite no difference in cardiac structure and function between patients with and without ID, and despite adjustment for the presence of anaemia, haemoglobin levels, cardiac rhythm, or New York Heart Association (NYHA) class. In the total CHF cohort, the PCr/ATP ratio correlated with ferritin levels (rho = 0.4, p < 0.01), and was higher in NYHA class I than class II or III patients (p = 0.02). CONCLUSION Iron deficiency is associated with greater cardiac energetic impairment in patients with CHF irrespective of anaemia and cardiac structure and function. Suppression of cardiac mitochondrial function might therefore be a mechanism via which ID worsens human CHF.
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Affiliation(s)
- Francesco Papalia
- King's College London British Heart Foundation Centre of ExcellenceSchool of Cardiovascular Medicine and Sciences, James Black CentreLondonUK
- Guy's and St Thomas' NHS Foundation TrustLondonUK
| | - Fadi Jouhra
- Guy's and St Thomas' NHS Foundation TrustLondonUK
- Lewisham & Greenwich NHS Foundation TrustLondonUK
- St George's University Hospitals NHS Foundation TrustLondonUK
| | | | - Ajay M. Shah
- King's College London British Heart Foundation Centre of ExcellenceSchool of Cardiovascular Medicine and Sciences, James Black CentreLondonUK
- Guy's and St Thomas' NHS Foundation TrustLondonUK
- King's College Hospital NHS Foundation TrustLondonUK
| | | | - Darlington O. Okonko
- King's College London British Heart Foundation Centre of ExcellenceSchool of Cardiovascular Medicine and Sciences, James Black CentreLondonUK
- Guy's and St Thomas' NHS Foundation TrustLondonUK
- King's College Hospital NHS Foundation TrustLondonUK
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3
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Tsampasian V, Swift AJ, Assadi H, Chowdhary A, Swoboda P, Sammut E, Dastidar A, Cabrero JB, Del Val JR, Nair S, Nijveldt R, Ryding A, Sawh C, Bucciarelli-Ducci C, Levelt E, Vassiliou V, Garg P. Myocardial inflammation and energetics by cardiac MRI: a review of emerging techniques. BMC Med Imaging 2021; 21:164. [PMID: 34749671 PMCID: PMC8573867 DOI: 10.1186/s12880-021-00695-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 10/28/2021] [Indexed: 11/10/2022] Open
Abstract
The role of inflammation in cardiovascular pathophysiology has gained a lot of research interest in recent years. Cardiovascular Magnetic Resonance has been a powerful tool in the non-invasive assessment of inflammation in several conditions. More recently, Ultrasmall superparamagnetic particles of iron oxide have been successfully used to evaluate macrophage activity and subsequently inflammation on a cellular level. Current evidence from research studies provides encouraging data and confirms that this evolving method can potentially have a huge impact on clinical practice as it can be used in the diagnosis and management of very common conditions such as coronary artery disease, ischaemic and non-ischaemic cardiomyopathy, myocarditis and atherosclerosis. Another important emerging concept is that of myocardial energetics. With the use of phosphorus magnetic resonance spectroscopy, myocardial energetic compromise has been proved to be an important feature in the pathophysiological process of several conditions including diabetic cardiomyopathy, inherited cardiomyopathies, valvular heart disease and cardiac transplant rejection. This unique tool is therefore being utilized to assess metabolic alterations in a wide range of cardiovascular diseases. This review systematically examines these state-of-the-art methods in detail and provides an insight into the mechanisms of action and the clinical implications of their use.
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Affiliation(s)
| | - Andrew J Swift
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK
| | - Hosamadin Assadi
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK
| | - Amrit Chowdhary
- Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
| | - Peter Swoboda
- Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
| | | | | | - Jordi Broncano Cabrero
- Cardiothoracic Imaging Unit, Hospital San Juan de Dios, Ressalta, HT Medica, Cordoba, Spain
| | - Javier Royuela Del Val
- Cardiothoracic Imaging Unit, Hospital San Juan de Dios, Ressalta, HT Medica, Cordoba, Spain
| | - Sunil Nair
- Norfolk and Norwich University Hospital, Norwich, UK
| | - Robin Nijveldt
- Cardiology Department, Radboudumc, Nijmegen, The Netherlands
| | | | - Chris Sawh
- Norfolk and Norwich University Hospital, Norwich, UK
| | | | - Eylem Levelt
- Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
| | - Vassilios Vassiliou
- Norwich Medical School, University of East Anglia, Norwich, UK.,Norfolk and Norwich University Hospital, Norwich, UK
| | - Pankaj Garg
- Norwich Medical School, University of East Anglia, Norwich, UK. .,Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK. .,Norfolk and Norwich University Hospital, Norwich, UK.
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4
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Abstract
The heart has the highest energy demands per gram of any organ in the body and energy metabolism fuels normal contractile function. Metabolic inflexibility and impairment of myocardial energetics occur with several common cardiac diseases, including ischemia and heart failure. This review explores several decades of innovation in cardiac magnetic resonance spectroscopy modalities and their use to noninvasively identify and quantify metabolic derangements in the normal, failing, and diseased heart. The implications of this noninvasive modality for predicting significant clinical outcomes and guiding future investigation and therapies to improve patient care are discussed.
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5
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Watson WD, Miller JJJ, Lewis A, Neubauer S, Tyler D, Rider OJ, Valkovič L. Use of cardiac magnetic resonance to detect changes in metabolism in heart failure. Cardiovasc Diagn Ther 2020; 10:583-597. [PMID: 32695639 DOI: 10.21037/cdt.2019.12.13] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The heart has a massive adenosine triphosphate (ATP) requirement, produced from the oxidation of metabolic substrates such as fat and glucose. Magnetic resonance spectroscopy offers a unique opportunity to probe this biochemistry: 31Phosphorus spectroscopy can demonstrate the production of ATP and quantify levels of the transport molecule phosphocreatine while 13Carbon spectroscopy can demonstrate the metabolic fates of glucose in real time. These techniques allow the metabolic deficits in heart failure to be interrogated and can be a potential future clinical tool.
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Affiliation(s)
- William D Watson
- Oxford Centre for Clinical Magnetic Resonance Research, Clarendon Laboratory, University of Oxford, Oxford, UK
| | - Jack J J Miller
- Oxford Centre for Clinical Magnetic Resonance Research, Clarendon Laboratory, University of Oxford, Oxford, UK.,Department of Physiology, Anatomy and Genetics, Clarendon Laboratory, University of Oxford, Oxford, UK.,Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, UK
| | - Andrew Lewis
- Oxford Centre for Clinical Magnetic Resonance Research, Clarendon Laboratory, University of Oxford, Oxford, UK
| | - Stefan Neubauer
- Oxford Centre for Clinical Magnetic Resonance Research, Clarendon Laboratory, University of Oxford, Oxford, UK
| | - Damian Tyler
- Oxford Centre for Clinical Magnetic Resonance Research, Clarendon Laboratory, University of Oxford, Oxford, UK.,Department of Physiology, Anatomy and Genetics, Clarendon Laboratory, University of Oxford, Oxford, UK
| | - Oliver J Rider
- Oxford Centre for Clinical Magnetic Resonance Research, Clarendon Laboratory, University of Oxford, Oxford, UK
| | - Ladislav Valkovič
- Oxford Centre for Clinical Magnetic Resonance Research, Clarendon Laboratory, University of Oxford, Oxford, UK.,Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sciences, Bratislava, Slovakia
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6
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Solaiyappan M, Weiss RG, Bottomley PA. Neural-network classification of cardiac disease from 31P cardiovascular magnetic resonance spectroscopy measures of creatine kinase energy metabolism. J Cardiovasc Magn Reson 2019; 21:49. [PMID: 31401975 PMCID: PMC6689869 DOI: 10.1186/s12968-019-0560-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 07/01/2019] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND The heart's energy demand per gram of tissue is the body's highest and creatine kinase (CK) metabolism, its primary energy reserve, is compromised in common heart diseases. Here, neural-network analysis is used to test whether noninvasive phosphorus (31P) cardiovascular magnetic resonance spectroscopy (CMRS) measurements of cardiac adenosine triphosphate (ATP) energy, phosphocreatine (PCr), the first-order CK reaction rate kf, and the rate of ATP synthesis through CK (CK flux), can predict specific human heart disease and clinical severity. METHODS The data comprised the extant 178 complete sets of PCr and ATP concentrations, kf, and CK flux data from human CMRS studies performed on clinical 1.5 and 3 Tesla scanners. Healthy subjects and patients with nonischemic cardiomyopathy, dilated (DCM) or hypertrophic disease, New York Heart Association (NYHA) class I-IV heart failure (HF), or with anterior myocardial infarction are included. Three-layer neural-networks were created to classify disease and to differentiate DCM, hypertrophy and clinical NYHA class in HF patients using leave-one-out training. Network performance was assessed using 'confusion matrices' and 'area-under-the-curve' (AUC) analyses of 'receiver operating curves'. Possible methodological bias and network imbalance were tested by segregating 1.5 and 3 Tesla data, and by data augmentation by random interpolation of nearest neighbors, respectively. RESULTS The network differentiated healthy, HF and non-HF cardiac disease with an overall accuracy of 84% and AUC > 90% for each category using the four CK metabolic parameters, alone. HF patients with DCM, hypertrophy, and different NYHA severity were differentiated with ~ 80% overall accuracy independent of CMRS methodology. CONCLUSIONS While sample-size was limited in some sub-classes, a neural network classifier applied to noninvasive cardiac 31P CMRS data, could serve as a metabolic biomarker for common disease types and HF severity with clinically-relevant accuracy. Moreover, the network's ability to individually classify disease and HF severity using CK metabolism alone, implies an intimate relationship between CK metabolism and disease, with subtle underlying phenotypic differences that enable their differentiation. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT00181259.
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Affiliation(s)
- Meiyappan Solaiyappan
- Division of MR Research, Department of Radiology, Johns Hopkins School of Medicine, Park Bldg. 310, 600 N Wolfe St, Baltimore, MD 21287 USA
| | - Robert G. Weiss
- Division of Cardiology, Department of Medicine, Johns Hopkins University, School of Medicine, Baltimore, MD USA
| | - Paul A. Bottomley
- Division of MR Research, Department of Radiology, Johns Hopkins School of Medicine, Park Bldg. 310, 600 N Wolfe St, Baltimore, MD 21287 USA
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7
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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.
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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
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8
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Abdurrachim D, Prompers JJ. Evaluation of cardiac energetics by non-invasive 31P magnetic resonance spectroscopy. Biochim Biophys Acta Mol Basis Dis 2017; 1864:1939-1948. [PMID: 29175056 DOI: 10.1016/j.bbadis.2017.11.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 11/17/2017] [Accepted: 11/18/2017] [Indexed: 01/10/2023]
Abstract
Alterations in myocardial energy metabolism have been implicated in the pathophysiology of cardiac diseases such as heart failure and diabetic cardiomyopathy. 31P magnetic resonance spectroscopy (MRS) is a powerful tool to investigate cardiac energetics non-invasively in vivo, by detecting phosphorus (31P)-containing metabolites involved in energy supply and buffering. In this article, we review the historical development of cardiac 31P MRS, the readouts used to assess cardiac energetics from 31P MRS, and how 31P MRS studies have contributed to the understanding of cardiac energy metabolism in heart failure and diabetes. This article is part of a Special issue entitled Cardiac adaptations to obesity, diabetes and insulin resistance, edited by Professors Jan F.C. Glatz, Jason R.B. Dyck and Christine Des Rosiers.
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Affiliation(s)
- Desiree Abdurrachim
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Functional Metabolism Group, Singapore Bioimaging Consortium, Agency for Science, Technology and Research, Singapore
| | - Jeanine J Prompers
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands.
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9
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Yan D, Afifi L, Jeon C, Trivedi M, Chang HW, Lee K, Liao W. The metabolomics of psoriatic disease. PSORIASIS (AUCKLAND, N.Z.) 2017; 7:1-15. [PMID: 28824870 PMCID: PMC5562362 DOI: 10.2147/ptt.s118348] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Metabolomics is an emerging new "omics" field involving the systematic analysis of the metabolites in a biologic system. These metabolites provide a molecular snapshot of cellular activity and are thus important for understanding the functional changes in metabolic pathways that drive disease. Recently, metabolomics has been used to study the local and systemic metabolic changes in psoriasis and its cardiometabolic comorbidities. Such studies have revealed novel insights into disease pathogenesis and suggest new biochemical signatures that may be used as a marker of psoriatic disease. This review will discuss common strategies in metabolomics analysis, current findings in the metabolomics of psoriasis, and emerging trends in psoriatic metabolomics.
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Affiliation(s)
- Di Yan
- Department of Dermatology, University of California-San Francisco, San Francisco, CA, USA
| | - Ladan Afifi
- Department of Dermatology, University of California-San Francisco, San Francisco, CA, USA
| | - Caleb Jeon
- Department of Dermatology, University of California-San Francisco, San Francisco, CA, USA
| | - Megha Trivedi
- Department of Dermatology, University of California-San Francisco, San Francisco, CA, USA
| | - Hsin Wen Chang
- Department of Dermatology, University of California-San Francisco, San Francisco, CA, USA
| | - Kristina Lee
- Department of Dermatology, University of California-San Francisco, San Francisco, CA, USA
| | - Wilson Liao
- Department of Dermatology, University of California-San Francisco, San Francisco, CA, USA
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10
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Clarke WT, Robson MD, Neubauer S, Rodgers CT. Creatine kinase rate constant in the human heart measured with 3D-localization at 7 tesla. Magn Reson Med 2016; 78:20-32. [PMID: 27579566 PMCID: PMC5484353 DOI: 10.1002/mrm.26357] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 06/26/2016] [Accepted: 07/06/2016] [Indexed: 12/21/2022]
Abstract
PURPOSE We present a new Bloch-Siegert four Angle Saturation Transfer (BOAST) method for measuring the creatine kinase (CK) first-order effective rate constant kf in human myocardium at 7 tesla (T). BOAST combines a variant of the four-angle saturation transfer (FAST) method using amplitude-modulated radiofrequency pulses, phosphorus Bloch-Siegert B1+-mapping to determine the per-voxel flip angles, and nonlinear fitting to Bloch simulations for postprocessing. METHODS Optimal flip angles and repetition time parameters were determined from Monte Carlo simulations. BOAST was validated in the calf muscle of two volunteers at 3T and 7T. The myocardial CK forward rate constant was then measured in 10 volunteers at 7T in 82 min (after 1 H localization). RESULTS BOAST kfCK values were 0.281 ± 0.002 s-1 in the calf and 0.35 ± 0.05 s-1 in myocardium. These are consistent with literature values from lower fields. Using a literature values for adenosine triphosphate concentration, we computed CK flux values of 4.55 ± 1.52 mmol kg-1 s-1 . The sensitive volume for BOAST depends on the B1 inhomogeneity of the transmit coil. CONCLUSION BOAST enables measurement of the CK rate constant in the human heart at 7T, with spatial localization in three dimensions to 5.6 mL voxels, using a 10-cm loop coil. Magn Reson Med 78:20-32, 2017. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
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Affiliation(s)
- William T Clarke
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Matthew D Robson
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Stefan Neubauer
- 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
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Schmidt R, Webb A. Characterization of an HEM-Mode Dielectric Resonator for 7-T Human Phosphorous Magnetic Resonance Imaging. IEEE Trans Biomed Eng 2016; 63:2390-2395. [PMID: 26929023 DOI: 10.1109/tbme.2016.2533659] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
GOAL To design and characterize a new set-up for dual nuclei MRI combining an annular dielectric resonator filled with high permittivity material for phosphorous (31P) and a traveling wave antenna for proton imaging. METHODS Recent studies have shown that an annular cylinder filled with water can serve as dielectric resonator for proton MRI of the extremities at 7 T. Using a very high permittivity material such as BaTiO3, this type of dielectric resonator can potentially be designed for lower gyromagnetic ratio nuclei. Combining this with a remote antenna for proton imaging, an alternative method for dual frequency imaging at ultrahigh field has been implemented. RESULTS 3D electromagnetic simulations were performed to examine the efficiency of the dielectric resonator. The new dielectric resonator was constructed for 31P acquisition at 121 MHz on a human 7 T MRI system. Phantom and in vivo scans demonstrated the feasibility of the setup, although the current sensitivity of the dielectric resonator is only half that of an equivalently sized birdcage. CONCLUSION The new approach offers a simple implementation for dual nuclei imaging at ultrahigh field, with several possibilities for further increases in sensitivity. SIGNIFICANCE Utilizing high permittivity materials enables very simple designs for high field RF coils: in the current configuration the interactions between the proton and phosphorous resonators are very low.
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12
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Brown R, Lakshmanan K, Madelin G, Alon L, Chang G, Sodickson DK, Regatte RR, Wiggins GC. A flexible nested sodium and proton coil array with wideband matching for knee cartilage MRI at 3T. Magn Reson Med 2015; 76:1325-34. [PMID: 26502310 DOI: 10.1002/mrm.26017] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 08/27/2015] [Accepted: 09/25/2015] [Indexed: 12/11/2022]
Abstract
PURPOSE We describe a 2 × 6 channel sodium/proton array for knee MRI at 3T. Multielement coil arrays are desirable because of well-known signal-to-noise ratio advantages over volume and single-element coils. However, low tissue-coil coupling that is characteristic of coils operating at low frequency can make the potential gains from a phased array difficult to realize. METHODS The issue of low tissue-coil coupling in the developed six-channel sodium receive array was addressed by implementing 1) a mechanically flexible former to minimize the coil-to-tissue distance and reduce the overall diameter of the array and 2) a wideband matching scheme that counteracts preamplifier noise degradation caused by coil coupling and a high-quality factor. The sodium array was complemented with a nested proton array to enable standard MRI. RESULTS The wideband matching scheme and tight-fitting mechanical design contributed to >30% central signal-to-noise ratio gain on the sodium module over a mononuclear sodium birdcage coil, and the performance of the proton module was sufficient for clinical imaging. CONCLUSION We expect the strategies presented in this study to be generally relevant in high-density receive arrays, particularly in x-nuclei or small animal applications. Magn Reson Med 76:1325-1334, 2016. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- 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.
| | - Karthik Lakshmanan
- 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
| | - Leeor Alon
- 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
| | - Gregory Chang
- 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
| | - Daniel K Sodickson
- 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
| | - Ravinder R Regatte
- 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
| | - Graham C Wiggins
- 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
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13
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Valkovič L, Bogner W, Gajdošík M, Považan M, Kukurová IJ, Krššák M, Gruber S, Frollo I, Trattnig S, Chmelík M. One-dimensional image-selected in vivo spectroscopy localized phosphorus saturation transfer at 7T. Magn Reson Med 2014; 72:1509-15. [PMID: 24470429 DOI: 10.1002/mrm.25058] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 10/30/2013] [Accepted: 11/05/2013] [Indexed: 01/07/2023]
Abstract
PURPOSE To evaluate the feasibility of a one-dimensional image-selected in vivo spectroscopy (1D-ISIS) saturation transfer (ST) sequence at 7T for localized in vivo measurements of energy metabolism in different tissues in clinically reasonable examination times. METHODS The performance of a gradient offset independent adiabacity-based 1D-ISIS localization was tested on phantom and the localized ST sequence was compared with the nonlocalized version in vivo. We performed localized measurements of basal metabolism of human liver and different muscle groups of the calf. Localized ST experiments took 15-25 minutes. RESULTS The selectivity of the 1D-ISIS sequence was 81.63% and the outer volume suppression was 97.57%. The ST parameters acquired with the 1D-ISIS sequence and with the nonlocalized acquisition in the muscle were not statistically different. The forward rate constants for phosphocreatine (PCr)-adenosine triphosphate (ATP) and inorganic phosphate (Pi)-ATP exchange reactions were measured in the soleus (kCK = 0.30 ± 0.06 s(-1) and kATP = 0.11 ± 0.02 s(-1) , respectively) and in the medial gastrocnemius (kCK = 0.27 ± 0.06 s(-1) and kATP = 0.09 ± 0.03s(-1) , respectively) in 15 minutes per muscle group. The corresponding fluxes were FCK = 6.26 ± 1.28 μmol/g/s, FATP = 0.22 ± 0.05 μmol/g/s and FCK = 6.29 ± 1.66 μmol/g/s, FATP = 0.21 ± 0.07 μmol/g/s, for soleus and gastrocnemius, respectively. The hepatic ATP synthesis measurement was feasible in 24 minutes. CONCLUSION The fast assessment of PCr-ATP and Pi-ATP exchange rates at 7T makes the 1D-ISIS ST sequence a promising tool for examining local resting-state metabolism in clinically acceptable measurement times.
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Affiliation(s)
- Ladislav Valkovič
- High Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University Vienna, Vienna, Austria; Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sciences, Bratislava, Slovakia
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El-Sharkawy AMM, Gabr RE, Schär M, Weiss RG, Bottomley PA. Quantification of human high-energy phosphate metabolite concentrations at 3 T with partial volume and sensitivity corrections. NMR IN BIOMEDICINE 2013; 26:1363-71. [PMID: 23729378 PMCID: PMC5239719 DOI: 10.1002/nbm.2961] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Revised: 02/25/2013] [Accepted: 03/09/2013] [Indexed: 05/23/2023]
Abstract
Practical noninvasive methods for the measurement of absolute metabolite concentrations are key to the assessment of the depletion of myocardial metabolite pools which occurs with several cardiac diseases, including infarction and heart failure. Localized MRS offers unique noninvasive access to many metabolites, but is often confounded by nonuniform sensitivity and partial volume effects in the large, poorly defined voxels commonly used for the detection of low-concentration metabolites with surface coils. These problems are exacerbated at higher magnetic field strengths by greater radiofrequency (RF) field inhomogeneity and differences in RF penetration with heteronuclear concentration referencing. An example is the (31)P measurement of cardiac adenosine triphosphate (ATP) and phosphocreatine (PCr) concentrations, which, although central to cardiac energetics, have not been measured at field strengths above 1.5 T. Here, practical acquisition and analysis protocols are presented for the quantification of [PCr] and [ATP] with one-dimensionally resolved surface coil spectra and concentration referencing at 3 T. The effects of nonuniform sensitivity and partial tissue volumes are addressed at 3 T by the application of MRI-based three-dimensional sensitivity weighting and tissue segmentation. The method is validated in phantoms of different sizes and concentrations, and used to measure [PCr] and [ATP] in healthy subjects. In calf muscle (n = 8), [PCr] = 24.7 ± 3.4 and [ATP] = 5.7 ± 1.3 µmol/g wet weight, whereas, in heart (n = 18), [PCr] = 10.4 ± 1.5 and [ATP] = 6.0 ± 1.1 µmol/g wet weight (all mean ± SD), consistent with previous reports at lower fields. The method enables, for the first time, the efficient, semi-automated quantification of high-energy phosphate metabolites in humans at 3 T with nonuniform excitation and detection.
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Affiliation(s)
- Abdel-Monem M El-Sharkawy
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Abraham MR, Bottomley PA, Dimaano VL, Pinheiro A, Steinberg A, Traill TA, Abraham TP, Weiss RG. Creatine kinase adenosine triphosphate and phosphocreatine energy supply in a single kindred of patients with hypertrophic cardiomyopathy. Am J Cardiol 2013; 112:861-6. [PMID: 23751935 DOI: 10.1016/j.amjcard.2013.05.017] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Revised: 05/02/2013] [Accepted: 05/02/2013] [Indexed: 01/20/2023]
Abstract
A lethal and extensively characterized familial form of hypertrophic cardiomyopathy (HC) is due to a point mutation (Arg403Gln) in the cardiac β-myosin heavy chain gene. Although this is associated with abnormal energy metabolism and progression to heart failure in an animal model, in vivo cardiac energetics have not been characterized in patients with this mutation. Noninvasive phosphorus saturation transfer magnetic resonance spectroscopy was used to measure the adenosine triphosphate supplied by the creatine kinase (CK) reaction and phosphocreatine, the heart's primary energy reserve, in 9 of 10 patients from a single kindred with HC caused by the Arg403GIn mutation and 17 age-matched healthy controls. Systolic and diastolic function was assessed by echocardiography in all 10 patients with HC. The patients with HC had impairment of diastolic function and mild systolic dysfunction, when assessed using global systolic longitudinal strain. Myocardial phosphocreatine was significantly decreased by 24% in patients (7.1 ± 2.3 μmol/g) compared with the controls (9.4 ± 1.2 μmol/g; p = 0.003). The pseudo-first-order CK rate-constant was 26% lower (0.28 ± 0.15 vs 0.38 ± 0.07 s⁻¹, p = 0.035) and the forward CK flux was 44% lower (2.0 ± 1.4 vs 3.6 ± 0.9 μmol/g/s, p = 0.001) than in the controls. The contractile abnormalities did not correlate with the metabolic indexes. In conclusion, myocardial phosphocreatine and CK-ATP delivery are significantly reduced in patients with HC caused by the Arg403Gln mutation, akin to previous results from mice with the same mutation. A lack of a relation between energetic and contractile abnormalities suggests the former result from the sarcomeric mutation and not a late consequence of mechanical dysfunction.
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Parasoglou P, Xia D, Chang G, Regatte RR. Dynamic three-dimensional imaging of phosphocreatine recovery kinetics in the human lower leg muscles at 3T and 7T: a preliminary study. NMR IN BIOMEDICINE 2013; 26:348-56. [PMID: 23065754 PMCID: PMC3696475 DOI: 10.1002/nbm.2866] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Revised: 08/20/2012] [Accepted: 08/22/2012] [Indexed: 05/11/2023]
Abstract
The rate of phosphocreatine (PCr) resynthesis after physical exercise has been extensively studied with phosphorus (³¹P)-MRS. Previous studies have used small surface coils that were limited to measuring one superficial muscle per experiment. This study focuses on the development and implementation of a spectrally selective three-dimensional turbo spin echo (3D-TSE) sequence at 3T and 7T with temporal resolution of 24 s, using two geometrically identical volume coils. We acquired imaging data of PCr recovery from four healthy volunteers and one diabetic patient, who performed plantar flexions using resistance bands. We segmented the anatomical regions of six different muscles from the lower leg, namely the gastrocnemius [lateral (GL) and medial (GM)], the tibialis [anterior (TA) and posterior (TP)], the soleus (S) and the peroneus (P) and measured the local PCr resynthesis rate constants. During the same examination, we also acquired unlocalized (³¹P-MRS data at a temporal resolution of 6 s. At 3T, the PCr resynthesis rate constants were measured at 25.4 ± 3.7 s [n = 4, mean ± standard deviation (SD)] using the MRS method and 25.6 ± 4.4 s using the MRI method. At 7T, the measured rates were 26.4 ± 3.2 s and 26.2 ± 4.7 s for MRS and MRI. Using our imaging method, we measured the local PCr resynthesis rate constants in six individual muscles of the lower leg (min/max 20.2/31.7 ). The recovery rate constants measured for the diabetic patient were 55.5 s (MRS) and 52.7 s (MRI). The successful implementation of our 3D-method suggests that imaging is possible at both fields with a relatively high spatial resolution (voxel size: 4.2 mL at 3T and 1.6 mL at 7T) using volume coils and that local PCr resynthesis rates can be obtained in a single measurement. The advantage of the imaging method is that it can highlight differences in PCr resynthesis rates between different muscles in a single measurement in order to study spatial gradients of metabolic properties of diseased states for which very little is currently known.
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Affiliation(s)
- Prodromos Parasoglou
- Quantitative Multinuclear Musculoskeletal Imaging Group, Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY, USA.
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Parasoglou P, Xia D, Chang G, Regatte RR. 3D-mapping of phosphocreatine concentration in the human calf muscle at 7 T: comparison to 3 T. Magn Reson Med 2013; 70:1619-25. [PMID: 23390003 DOI: 10.1002/mrm.24616] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 11/27/2012] [Accepted: 12/05/2012] [Indexed: 01/09/2023]
Abstract
PURPOSE The development and implementation of a spectrally selective 3D-Turbo Spin Echo sequence for quantitative mapping of phosphocreatine (PCr) concentration in different muscles of the lower leg of healthy volunteers both at 3 T and 7 T. METHODS Nine healthy volunteers were recruited, all of whom where scanned at 3 T and 7 T. Three dimensional PCr concentration maps were obtained after images were corrected for B1 inhomogeneities, T1 relaxation weighting, and partial volume of fatty tissue in the muscles. Two volunteers performed plantar flexions inside the magnet, and the oxidative capacity of their muscles was estimated. RESULTS Three dimensional PCr concentration maps were obtained, with full muscle coverage and nominal voxel size of 0.52 mL at both fields. At 7 T a 2.7-fold increase of signal-to-noise ratio was achieved compared to 3 T. CONCLUSION Imaging (31) P metabolites at 7 T allowed for significant increase in signal to noise ratio compared to imaging at 3 T, while quantification of the PCr concentration remained unaffected. The importance of such an increase in signal-to-noise ratio is 2-fold, first higher resolution images with reduced partial volume effects can be acquired, and second multiple measurements such as dynamic imaging of PCr post-exercise, (31) P magnetization transfer, or other (1) H measurements, can be acquired in a single imaging session.
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Affiliation(s)
- Prodromos Parasoglou
- Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, New York, USA
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Acquisition-weighted chemical shift imaging improves SLOOP quantification of human cardiac phosphorus metabolites. Z Med Phys 2013; 24:49-54. [PMID: 23375741 DOI: 10.1016/j.zemedi.2013.01.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 12/19/2012] [Accepted: 01/10/2013] [Indexed: 11/22/2022]
Abstract
PURPOSE Phosphorous metabolite ratios in human myocardium were determined by a combination of acquisition weighted CSI and a SLOOP evaluation and the results were compared to corresponding SLOOP experiments using standard CSI. MATERIALS AND METHODS 10 healthy subjects were examined at 1.5 T using both standard CSI and acquisition weighted CSI. Both experiments were performed with a similar acquisition time and the same spatial resolution. The PCr/ATP ratio was determined and the localization properties of both experiments were compared. RESULTS The PCr/ATP ratio of 2.2±0.4 found for the experiment using acquisition weighted CSI was almost identical to the value of 2.0±0.4 for standard CSI. The sensitivity and the localization properties improved in all subjects using SLOOP evaluation of the acquisition weighted sampling in comparison to the standard CSI acquisition with an average of 3% and 18%, respectively. CONCLUSION The employment of acquisition weighting allows for a further improvement of the (31)P SLOOP spectroscopy of the human heart.
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Parasoglou P, Xia D, Regatte RR. Spectrally selective 3D TSE imaging of phosphocreatine in the human calf muscle at 3 T. Magn Reson Med 2012; 69:812-7. [PMID: 22499078 DOI: 10.1002/mrm.24288] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Revised: 03/14/2012] [Accepted: 03/16/2012] [Indexed: 12/29/2022]
Abstract
Quantitative information about concentrations of several metabolites in human skeletal muscle can be obtained through localized (31)P magnetic resonance spectroscopy methods. However, these methods have shortcomings: long acquisition times, limited volume coverage, and coarse resolution. Significantly higher spatial and temporal resolution of imaging of single metabolites can be achieved through spectrally selective three-dimensional imaging methods. This study reports the implementation of a three-dimensional spectrally selective turbo spin-echo sequence, on a 3T clinical system, to map the concentration of phosphocreatine in the human calf muscle with significantly increased spatial resolution and in a clinically feasible scan time. Absolute phosphocreatine quantification was performed with the use of external phantoms after relaxation and flip angle correction of the turbo spin-echo voxel signal. The mean ± standard deviation of the phosphocreatine concentration measured in five healthy volunteers was 29.4 ± 2.5 mM with signal-to-noise ratio of 14:1 and voxel size of 0.52 mL.
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Affiliation(s)
- Prodromos Parasoglou
- Quantitative Multinuclear Musculoskeletal Imaging Group, Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, New York 10016, USA.
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Metabolomics: the apogee of the omics trilogy. Nat Rev Mol Cell Biol 2012. [DOI: 10.1038/nrm3314 and 4394=4394-- scwx] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Patti GJ, Yanes O, Siuzdak G. Metabolomics: the apogee of the omics trilogy. Nat Rev Mol Cell Biol 2012. [DOI: 10.1038/nrm3314 order by 1#] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Patti GJ, Yanes O, Siuzdak G. Metabolomics: the apogee of the omics trilogy. Nat Rev Mol Cell Biol 2012. [DOI: 10.1038/nrm3314 and 5927=6679-- elyo] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Patti GJ, Yanes O, Siuzdak G. Metabolomics: the apogee of the omics trilogy. Nat Rev Mol Cell Biol 2012. [DOI: 10.1038/nrm3314 and 3511=(select (case when (3511=3511) then 3511 else (select 9304 union select 4747) end))-- isaz] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Patti GJ, Yanes O, Siuzdak G. Metabolomics: the apogee of the omics trilogy. Nat Rev Mol Cell Biol 2012. [DOI: 10.1038/nrm3314 rlike (select (case when (1444=9719) then 0x31302e313033382f6e726d33333134 else 0x28 end))-- dyhd] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Patti GJ, Yanes O, Siuzdak G. Metabolomics: the apogee of the omics trilogy. Nat Rev Mol Cell Biol 2012. [DOI: 10.1038/nrm3314 and 4394=4394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Metabolomics: the apogee of the omics trilogy. Nat Rev Mol Cell Biol 2012. [DOI: 10.1038/nrm3314 order by 1-- zarb] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Patti GJ, Yanes O, Siuzdak G. Metabolomics: the apogee of the omics trilogy. Nat Rev Mol Cell Biol 2012. [DOI: 10.1038/nrm3314 rlike (select (case when (2201=2201) then 0x31302e313033382f6e726d33333134 else 0x28 end))] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Patti GJ, Yanes O, Siuzdak G. Metabolomics: the apogee of the omics trilogy. Nat Rev Mol Cell Biol 2012. [DOI: 10.1038/nrm3314 and extractvalue(1964,concat(0x5c,0x7176717a71,(select (elt(1964=1964,1))),0x7170716a71))] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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