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Chen H, De Feyter HM, Brown PB, Rothman DL, Cai S, de Graaf RA. Comparison of direct 13C and indirect 1H-[ 13C] MR detection methods for the study of dynamic metabolic turnover in the human brain. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2017; 283:33-44. [PMID: 28869920 DOI: 10.1016/j.jmr.2017.08.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 08/02/2017] [Accepted: 08/10/2017] [Indexed: 06/07/2023]
Abstract
A wide range of direct 13C and indirect 1H-[13C] MR detection methods exist to probe dynamic metabolic pathways in the human brain. Choosing an optimal detection method is difficult as sequence-specific features regarding spatial localization, broadband decoupling, spectral resolution, power requirements and sensitivity complicate a straightforward comparison. Here we combine density matrix simulations with experimentally determined values for intrinsic 1H and 13C sensitivity, T1 and T2 relaxation and transmit efficiency to allow selection of an optimal 13C MR detection method for a given application and magnetic field. The indirect proton-observed, carbon-edited (POCE) detection method provides the highest accuracy at reasonable RF power deposition both at 4T and 7T. The various polarization transfer methods all have comparable performances, but may become infeasible at 7T due to the high RF power deposition. 2D MR methods have limited value for the metabolites considered (primarily glutamate, glutamine and γ-amino butyric acid (GABA)), but may prove valuable when additional information can be extracted, such as isotopomers or lipid composition. While providing the lowest accuracy, the detection of non-protonated carbons is the simplest to implement with the lowest RF power deposition. The magnetic field homogeneity is one of the most important parameters affecting the detection accuracy for all metabolites and all acquisition methods.
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Affiliation(s)
- Hao Chen
- Magnetic Resonance Research Center, Department of Radiology and Biomedical Imaging, Yale University, School of Medicine, New Haven, CT, USA; Department of Electronic Science, Xiamen University, Xiamen, Fujian, China
| | - Henk M De Feyter
- Magnetic Resonance Research Center, Department of Radiology and Biomedical Imaging, Yale University, School of Medicine, New Haven, CT, USA
| | - Peter B Brown
- Magnetic Resonance Research Center, Department of Radiology and Biomedical Imaging, Yale University, School of Medicine, New Haven, CT, USA
| | - Douglas L Rothman
- Magnetic Resonance Research Center, Department of Radiology and Biomedical Imaging, Yale University, School of Medicine, New Haven, CT, USA
| | - Shuhui Cai
- Department of Electronic Science, Xiamen University, Xiamen, Fujian, China
| | - Robin A de Graaf
- Magnetic Resonance Research Center, Department of Radiology and Biomedical Imaging, Yale University, School of Medicine, New Haven, CT, USA.
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Magnetic Resonance Spectroscopy and its Clinical Applications: A Review. J Med Imaging Radiat Sci 2017; 48:233-253. [PMID: 31047406 DOI: 10.1016/j.jmir.2017.06.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Revised: 04/30/2017] [Accepted: 06/22/2017] [Indexed: 12/25/2022]
Abstract
In vivo NMR spectroscopy is known as magnetic resonance spectroscopy (MRS). MRS has been applied as both a research and a clinical tool in order to detect visible or nonvisible abnormalities. The adaptability of MRS allows a technique that can probe a wide variety of metabolic uses across different tissues. Although MRS is mostly applied for brain tissue, it can be used for detection, localization, staging, tumour aggressiveness evaluation, and tumour response assessment of breast, prostate, hepatic, and other cancers. In this article, the medical applications of MRS in the brain, including tumours, neural and psychiatric disorder studies, breast, prostate, hepatic, gastrointestinal, and genitourinary investigations have been reviewed.
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Lai M, Gruetter R, Lanz B. Progress towards in vivo brain 13C-MRS in mice: Metabolic flux analysis in small tissue volumes. Anal Biochem 2017; 529:229-244. [PMID: 28119064 DOI: 10.1016/j.ab.2017.01.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Revised: 01/19/2017] [Accepted: 01/20/2017] [Indexed: 01/08/2023]
Abstract
The combination of dynamic 13C MRS data under infusion of 13C-labelled substrates and compartmental models of cerebral metabolism enabled in vivo measurement of metabolic fluxes with a quantitative and distinct determination of cellular-specific activities. The non-invasive nature and the chemical specificity of the 13C dynamic data obtained in those tracer experiments makes it an attractive approach offering unique insights into cerebral metabolism. Genetically engineered mice present a wealth of disease models particularly interesting for the neuroscience community. Nevertheless, in vivo13C NMR studies of the mouse brain are only recently appearing in the field due to the numerous challenges linked to the small mouse brain volume and the difficulty to follow the mouse physiological parameters within the NMR system during the infusion experiment. This review will present the progresses in the quest for a higher in vivo13C signal-to-noise ratio up to the present state of the art techniques, which made it feasible to assess glucose metabolism in different regions of the mouse brain. We describe how experimental results were integrated into suitable compartmental models and how a deep understanding of cerebral metabolism depends on the reliable detection of 13C in the different molecules and carbon positions.
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Affiliation(s)
- Marta Lai
- Laboratory for Functional and Metabolic Imaging (LIFMET), École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.
| | - Rolf Gruetter
- Laboratory for Functional and Metabolic Imaging (LIFMET), École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland; Department of Radiology, University of Geneva, 1205 Geneva, Switzerland; Department of Radiology, University of Lausanne, 1015 Lausanne, Switzerland
| | - Bernard Lanz
- Laboratory for Functional and Metabolic Imaging (LIFMET), École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland; Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, United Kingdom
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4
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Wijnen JP, Klomp DWJ, Nabuurs CIHC, de Graaf RA, van Kalleveen IML, van der Kemp WJM, Luijten PR, Kruit MC, Webb A, Kan HE, Boer VO. Proton observed phosphorus editing (POPE) for in vivo detection of phospholipid metabolites. NMR IN BIOMEDICINE 2016; 29:1222-1230. [PMID: 26601921 DOI: 10.1002/nbm.3440] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 09/03/2015] [Accepted: 10/08/2015] [Indexed: 06/05/2023]
Abstract
The purpose of this article was to compare the sensitivity of proton observed phosphorus editing (POPE) with direct (31) P MRS with Ernst angle excitation for (1) H-(31) P coupled metabolites at 7 T. POPE sequences were developed for detecting phosphocholine (PC), phosphoethanolamine (PE), glycerophosphocholine (GPC), and glycerophosphoethanolamine (GPE) on the (1) H channel, thereby using the enhanced sensitivity of the (1) H nuclei over (31) P detection. Five healthy volunteers were examined with POPE and (31) P-MRS. POPE editing showed a more than doubled sensitivity in an ideal phantom experiment as compared with direct (31) P MRS with Ernst angle excitation. In vivo, despite increased relaxation losses, significant gains in signal-to-noise ratio (SNR) of 30-40% were shown for PE and GPE + PC levels in the human brain. The SNR of GPC was lower in the POPE measurement compared with the (31) P-MRS measurement. Furthermore, selective narrowband editing on the (31) P channel showed the ability to separate the overlapping GPE and PE signals in the (1) H spectrum. POPE can be used for enhanced detection of (1) H-(31) P coupled metabolites in vivo. Copyright © 2015 John Wiley & Sons, Ltd.
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Affiliation(s)
- Jannie P Wijnen
- Department of Radiology, University Medical Centre Utrecht, Utrecht, The Netherlands
- Department of Radiology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Dennis W J Klomp
- Department of Radiology, University Medical Centre Utrecht, Utrecht, The Netherlands
| | | | - Robin A de Graaf
- Department of Radiology, University Medical Centre Utrecht, Utrecht, The Netherlands
- Department of Diagnostic Radiology, Yale University, New Haven, CT, USA
| | | | - Wybe J M van der Kemp
- Department of Radiology, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Peter R Luijten
- Department of Radiology, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Mark C Kruit
- Department of Radiology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Andrew Webb
- Department of Radiology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Hermien E Kan
- Department of Radiology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Vincent O Boer
- Department of Radiology, University Medical Centre Utrecht, Utrecht, The Netherlands
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5
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Meyerspeer M, Magill AW, Kuehne A, Gruetter R, Moser E, Schmid AI. Simultaneous and interleaved acquisition of NMR signals from different nuclei with a clinical MRI scanner. Magn Reson Med 2015; 76:1636-1641. [PMID: 26608834 PMCID: PMC4996325 DOI: 10.1002/mrm.26056] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2015] [Revised: 10/16/2015] [Accepted: 10/25/2015] [Indexed: 11/17/2022]
Abstract
Purpose Modification of a clinical MRI scanner to enable simultaneous or rapid interleaved acquisition of signals from two different nuclei. Methods A device was developed to modify the local oscillator signal fed to the receive channel(s) of an MRI console. This enables external modification of the frequency at which the receiver is sensitive and rapid switching between different frequencies. Use of the device was demonstrated with interleaved and simultaneous 31P and 1H spectroscopic acquisitions, and with interleaved 31P and 1H imaging. Results Signal amplitudes and signal‐to‐noise ratios were found to be unchanged for the modified system, compared with data acquired with the MRI system in the standard configuration. Conclusion Interleaved and simultaneous 1H and 31P signal acquisition was successfully demonstrated with a clinical MRI scanner, with only minor modification of the RF architecture. While demonstrated with 31P, the modification is applicable to any detectable nucleus without further modification, enabling a wide range of simultaneous and interleaved experiments to be performed within a clinical setting. Magn Reson Med 76:1636–1641, 2016. © 2015 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)
- Martin Meyerspeer
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria. .,MR Centre of Excellence, Medical University of Vienna, Austria. .,Laboratory for Functional and Metabolic Imaging, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
| | - Arthur W Magill
- Laboratory for Functional and Metabolic Imaging, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.,Department of Radiology, University of Lausanne, Lausanne, Switzerland
| | - Andre Kuehne
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria.,MR Centre of Excellence, Medical University of Vienna, Austria
| | - Rolf Gruetter
- Laboratory for Functional and Metabolic Imaging, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.,Department of Radiology, University of Lausanne, Lausanne, Switzerland.,Department of Radiology, University of Geneva, Geneva, Switzerland
| | - Ewald Moser
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria.,MR Centre of Excellence, Medical University of Vienna, Austria
| | - Albrecht Ingo Schmid
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria.,MR Centre of Excellence, Medical University of Vienna, Austria
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van de Ven KC, Tack CJ, Heerschap A, van der Graaf M, de Galan BE. Patients with type 1 diabetes exhibit altered cerebral metabolism during hypoglycemia. J Clin Invest 2013; 123:623-9. [PMID: 23298837 PMCID: PMC3561817 DOI: 10.1172/jci62742] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Accepted: 11/08/2012] [Indexed: 01/24/2023] Open
Abstract
Patients with type 1 diabetes mellitus (T1DM) experience, on average, 2 to 3 hypoglycemic episodes per week. This study investigated the effect of hypoglycemia on cerebral glucose metabolism in patients with uncomplicated T1DM. For this purpose, hyperinsulinemic euglycemic and hypoglycemic glucose clamps were performed on separate days, using [1-13C]glucose infusion to increase plasma 13C enrichment. In vivo brain 13C magnetic resonance spectroscopy was used to measure the time course of 13C label incorporation into different metabolites and to calculate the tricarboxylic acid cycle flux (VTCA) by a one-compartment metabolic model. We found that cerebral glucose metabolism, as reflected by the VTCA, was not significantly different comparing euglycemic and hypoglycemic conditions in patients with T1DM. However, the VTCA was inversely related to the HbA1C and was, under hypoglycemic conditions, approximately 45% higher than that in a previously investigated group of healthy subjects. These data suggest that the brains of patients with T1DM are better able to endure moderate hypoglycemia than those of subjects without diabetes.
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Affiliation(s)
- Kim C.C. van de Ven
- Department of Radiology,
Department of General Internal Medicine, and
Clinical Physics Laboratory, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Cees J. Tack
- Department of Radiology,
Department of General Internal Medicine, and
Clinical Physics Laboratory, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Arend Heerschap
- Department of Radiology,
Department of General Internal Medicine, and
Clinical Physics Laboratory, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Marinette van der Graaf
- Department of Radiology,
Department of General Internal Medicine, and
Clinical Physics Laboratory, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Bastiaan E. de Galan
- Department of Radiology,
Department of General Internal Medicine, and
Clinical Physics Laboratory, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
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7
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van de Ven KC, van der Graaf M, Tack CJ, Heerschap A, de Galan BE. Steady-state brain glucose concentrations during hypoglycemia in healthy humans and patients with type 1 diabetes. Diabetes 2012; 61:1974-7. [PMID: 22688331 PMCID: PMC3402320 DOI: 10.2337/db11-1778] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The objective of this study was to investigate the relationship between plasma and brain glucose levels during euglycemia and hypoglycemia in healthy subjects and patients with type 1 diabetes mellitus (T1DM). Hyperinsulinemic euglycemic (5 mmol/L) and hypoglycemic (3 mmol/L) [1-(13)C]glucose clamps were performed in eight healthy subjects and nine patients with uncomplicated T1DM (HbA(1c) 7.7 ± 1.4%). Brain glucose levels were measured by (13)C magnetic resonance spectroscopy. Linear regression analysis was used to fit the relationship between plasma and brain glucose levels and calculate reversible Michaelis-Menten (MM) kinetic parameters. Brain glucose values during euglycemia (1.1 ± 0.4 μmol/g vs. 1.1 ± 0.3 μmol/g; P = 0.95) and hypoglycemia (0.5 ± 0.2 μmol/g vs. 0.6 ± 0.3 μmol/g; P = 0.52) were comparable between healthy subjects and T1DM patients. MM kinetic parameters of combined data were calculated to be maximum transport rate/cerebral metabolic rate of glucose (T(max)/CMR(glc)) = 2.25 ± 0.32 and substrate concentration at half maximal transport (K(t)) = 1.53 ± 0.88 mmol/L, which is in line with previously published data obtained under hyperglycemic conditions. In conclusion, the linear MM relationship between plasma and brain glucose can be extended to low plasma glucose levels. We found no evidence that the plasma to brain glucose relationship or the kinetics describing glucose transport over the blood-brain barrier differ between healthy subjects and patients with uncomplicated, reasonably well-controlled T1DM.
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Affiliation(s)
- Kim C.C. van de Ven
- Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen, the Netherlands
| | - Marinette van der Graaf
- Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen, the Netherlands
- Clinical Physics Laboratory, Radboud University Nijmegen Medical Centre, Nijmegen, the Netherlands
| | - Cees J. Tack
- Department of General Internal Medicine, Radboud University Nijmegen Medical Centre, Nijmegen, the Netherlands
| | - Arend Heerschap
- Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen, the Netherlands
| | - Bastiaan E. de Galan
- Department of General Internal Medicine, Radboud University Nijmegen Medical Centre, Nijmegen, the Netherlands
- Corresponding author: Bastiaan E. de Galan,
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ter Voert EGW, Heijmen L, van Laarhoven HWM, Heerschap A. In vivo magnetic resonance spectroscopy of liver tumors and metastases. World J Gastroenterol 2011; 17:5133-49. [PMID: 22215937 PMCID: PMC3243879 DOI: 10.3748/wjg.v17.i47.5133] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2011] [Revised: 02/04/2011] [Accepted: 02/11/2011] [Indexed: 02/06/2023] Open
Abstract
Primary liver cancer is the fifth most common malignancy in men and the eighth in women worldwide. The liver is also the second most common site for metastatic spread of cancer. To assist in the diagnosis of these liver lesions non-invasive advanced imaging techniques are desirable. Magnetic resonance (MR) is commonly used to identify anatomical lesions, but it is a very versatile technique and also can provide specific information on tumor pathophysiology and metabolism, in particular with the application of MR spectroscopy (MRS). This may include data on the type, grade and stage of tumors, and thus assist in further management of the disease. The purpose of this review is to summarize and discuss the available literature on proton, phosphorus and carbon-13-MRS as performed on primary liver tumors and metastases, with human applications as the main perspective. Upcoming MRS approaches with potential applications to liver tumors are also included. Since knowledge of some technical background is indispensable to understand the results, a basic introduction of MRS and some technical issues of MRS as applied to tumors and metastases in the liver are described as well. In vivo MR spectroscopy of tumors in a metabolically active organ such as the liver has been demonstrated to provide important information on tumor metabolism, but it also is challenging as compared to applications on some other tissues, in particular in humans, mostly because of its abdominal location where movement may be a disturbing factor.
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van de Ven KCC, de Galan BE, van der Graaf M, Shestov AA, Henry PG, Tack CJJ, Heerschap A. Effect of acute hypoglycemia on human cerebral glucose metabolism measured by ¹³C magnetic resonance spectroscopy. Diabetes 2011; 60:1467-73. [PMID: 21464446 PMCID: PMC3292319 DOI: 10.2337/db10-1592] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To investigate the effect of acute insulin-induced hypoglycemia on cerebral glucose metabolism in healthy humans, measured by (13)C magnetic resonance spectroscopy (MRS). RESEARCH DESIGN AND METHODS Hyperinsulinemic glucose clamps were performed at plasma glucose levels of 5 mmol/L (euglycemia) or 3 mmol/L (hypoglycemia) in random order in eight healthy subjects (four women) on two occasions, separated by at least 3 weeks. Enriched [1-(13)C]glucose 20% w/w was used for the clamps to maintain stable plasma glucose labeling. The levels of the (13)C-labeled glucose metabolites glutamate C4 and C3 were measured over time in the occipital cortex during the clamp by continuous (13)C MRS in a 3T magnetic resonance scanner. Time courses of glutamate C4 and C3 labeling were fitted using a one-compartment model to calculate metabolic rates in the brain. RESULTS Plasma glucose (13)C isotopic enrichment was stable at 35.1 ± 1.8% during euglycemia and at 30.2 ± 5.5% during hypoglycemia. Hypoglycemia stimulated release of counterregulatory hormones (all P < 0.05) and tended to increase plasma lactate levels (P = 0.07). After correction for the ambient (13)C enrichment values, label incorporation into glucose metabolites was virtually identical under both glycemic conditions. Calculated tricarboxylic acid cycle rates (V(TCA)) were 0.48 ± 0.03 μmol/g/min during euglycemia and 0.43 ± 0.08 μmol/g/min during hypoglycemia (P = 0.42). CONCLUSIONS These results indicate that acute moderate hypoglycemia does not affect fluxes through the main pathways of glucose metabolism in the brain of healthy nondiabetic subjects.
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Affiliation(s)
- Kim C C van de Ven
- Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
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Li S, Zhang Y, Wang S, Araneta MF, Johnson CS, Xiang Y, Innis RB, Shen J. 13C MRS of occipital and frontal lobes at 3 T using a volume coil for stochastic proton decoupling. NMR IN BIOMEDICINE 2010; 23:977-85. [PMID: 20878974 PMCID: PMC3159869 DOI: 10.1002/nbm.1524] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Previously, we devised a novel strategy for in vivo 13C MRS using [2-13C]glucose infusion and low-power proton decoupling, and proposed that this strategy could be used to acquire 13C MR spectra from the frontal lobe of the human brain. Here, we demonstrate, for the first time, in vivo 13C MRS of human frontal lobe acquired at 3 T. Because the primary metabolites of [2-13C]glucose can be decoupled using very-low-radiofrequency power, we used a volume coil for proton decoupling in this study. The homogeneous B(1) field of the volume coil was found to significantly enhance the decoupling efficiency of the stochastic decoupling sequence. Detailed specific absorption rates inside the human head were analyzed using the finite difference time domain method to ensure experimental safety. In vivo 13C spectra from the occipital and frontal lobes of the human brain were obtained. At a decoupling power of 30 W (time-averaged power, 2.45 W), the spectra from the occipital lobe showed well-resolved spectral resolution and excellent signal-to-noise ratio. Although frontal lobe 13C spectra were affected by local B(0) field inhomogeneity, we demonstrated that the spectral quality could be improved using post-acquisition data processing. In particular, we showed that the frontal lobe glutamine C5 at 178.5 ppm and aspartate C4 at 178.3 ppm could be spectrally resolved with effective proton decoupling and B(0) field correction. Because of its large spatial coverage, volume coil decoupling provides the potential to acquire 13C MRS from more than one brain region simultaneously.
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Affiliation(s)
- Shizhe Li
- Magnetic Resonance Spectroscopy Core Facility, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Yan Zhang
- Magnetic Resonance Spectroscopy Core Facility, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Shumin Wang
- Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Maria Ferraris Araneta
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Christopher S. Johnson
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Yun Xiang
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Robert B. Innis
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Jun Shen
- Magnetic Resonance Spectroscopy Core Facility, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
- Correspondence to: J. Shen, Molecular Imaging Branch, National Institute of Mental Health, Bldg. 10, Rm. 2D51A, 9000 Rockville Pike, Bethesda, MD 20892-1527, USA.
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Wijnen JP, Van der Graaf M, Scheenen TWJ, Klomp DWJ, de Galan BE, Idema AJS, Heerschap A. In vivo 13C magnetic resonance spectroscopy of a human brain tumor after application of 13C-1-enriched glucose. Magn Reson Imaging 2010; 28:690-7. [PMID: 20399584 DOI: 10.1016/j.mri.2010.03.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2009] [Revised: 01/13/2010] [Accepted: 03/05/2010] [Indexed: 10/19/2022]
Abstract
OBJECTIVES As a unique tool to assess metabolic fluxes noninvasively, (13)C magnetic resonance spectroscopy (MRS) could help to characterize and understand malignancy in human tumors. However, its low sensitivity has hampered applications in patients. The aim of this study was to demonstrate that with sensitivity-optimized localized (13)C MRS and intravenous infusion of [1-(13)C]glucose under euglycemia, it is possible to assess the dynamic conversion of glucose into its metabolic products in vivo in human glioma tissue. MATERIALS AND METHODS Measurements were done at 3 T with a broadband single RF channel and a quadrature (13)C surface coil inserted in a (1)H volume coil. A (1)H/(13)C polarization transfer sequence was applied, modified for localized acquisition, alternatively in two (50 ml) voxels, one encompassing the tumor and the other normal brain tissue. RESULTS After about 20 min of [1-(13)C]glucose infusion, a [3-(13)C]lactate signal appeared among several resonances of metabolic products of glucose in MR spectra of the tumor voxel. The resonance of [3-(13)C]lactate was absent in MR spectra from contralateral tissue. In addition, the intensity of [1-(13)C]glucose signals in the tumor area was about 50% higher than that in normal tissue, likely reflecting more glucose in extracellular space due to a defective blood-brain barrier. The signal intensity for metabolites produced in or via the tricarboxylic acid (TCA) cycle was lower in the tumor than in the contralateral area, albeit that the ratios of isotopomer signals were comparable. CONCLUSION With an improved (13)C MRS approach, the uptake of glucose and its conversion into metabolites such as lactate can be monitored noninvasively in vivo in human brain tumors. This opens the way to assessing metabolic activity in human tumor tissue.
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Affiliation(s)
- Jannie P Wijnen
- Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
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Li S, Zhang Y, Wang S, Yang J, Ferraris Araneta M, Farris A, Johnson C, Fox S, Innis R, Shen J. In vivo 13C magnetic resonance spectroscopy of human brain on a clinical 3 T scanner using [2-13C]glucose infusion and low-power stochastic decoupling. Magn Reson Med 2009; 62:565-73. [PMID: 19526500 DOI: 10.1002/mrm.22044] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
This study presents the detection of [2-(13)C]glucose metabolism in the carboxylic/amide region in the human brain, and demonstrates that the cerebral metabolism of [2-(13)C]glucose can be studied in human subjects in the presence of severe hardware constraints of widely available 3 T clinical scanners and with low-power stochastic decoupling. In the carboxylic/amide region of human brain, the primary products of (13)C label incorporation from [2-(13)C]glucose into glutamate, glutamine, aspartate, gamma-aminobutyric acid, and N-acetylaspartate were detected. Unlike the commonly used alkanyl region where lipid signals spread over a broad frequency range, the carboxylic carbon signal of lipids was found to be confined to a narrow range centered at 172.5 ppm and present no spectral interference in the absence of lipid suppression. Comparison using phantoms shows that stochastic decoupling is far superior to the commonly used WALTZ sequence at very low decoupling power at 3 T. It was found that glutamine C1 and C5 can be decoupled using stochastic decoupling at 2.2 W, although glutamine protons span a frequency range of approximately 700 Hz. Detailed specific absorption rate analysis was also performed using finite difference time domain numerical simulation.
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Affiliation(s)
- Shizhe Li
- Magnetic Resonance Spectroscopy Core Facility, NIMH, National Institutes of Health, Bethesda, Maryland 20892-1527, USA
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van de Ven KCC, van der Graaf M, Tack CJJ, Klomp DWJ, Heerschap A, de Galan BE. Optimized [1-(13)C]glucose infusion protocol for 13C magnetic resonance spectroscopy at 3T of human brain glucose metabolism under euglycemic and hypoglycemic conditions. J Neurosci Methods 2009; 186:68-71. [PMID: 19913052 DOI: 10.1016/j.jneumeth.2009.10.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2009] [Revised: 10/28/2009] [Accepted: 10/30/2009] [Indexed: 11/19/2022]
Abstract
The effect of insulin-induced hypoglycemia on cerebral glucose metabolism is largely unknown. (13)C MRS is a unique tool to study cerebral glucose metabolism, but the concurrent requirement for [1-(13)C]glucose administration limits its use under hypoglycemic conditions. To facilitate (13)C MRS data analysis we designed separate [1-(13)C]glucose infusion protocols for hyperinsulinemic euglycemic and hypoglycemic clamps in such a way that plasma isotopic enrichment of glucose was stable and comparable under both glycemic conditions. (13)C MR spectra were acquired with optimized (13)C MRS measurement techniques to obtain high quality (13)C MR spectra with these protocols.
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Affiliation(s)
- Kim C C van de Ven
- Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
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14
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van der Graaf M. In vivo magnetic resonance spectroscopy: basic methodology and clinical applications. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2009; 39:527-40. [PMID: 19680645 PMCID: PMC2841275 DOI: 10.1007/s00249-009-0517-y] [Citation(s) in RCA: 158] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2009] [Revised: 06/12/2009] [Accepted: 06/29/2009] [Indexed: 12/21/2022]
Abstract
The clinical use of in vivo magnetic resonance spectroscopy (MRS) has been limited for a long time, mainly due to its low sensitivity. However, with the advent of clinical MR systems with higher magnetic field strengths such as 3 Tesla, the development of better coils, and the design of optimized radio-frequency pulses, sensitivity has been considerably improved. Therefore, in vivo MRS has become a technique that is routinely used more and more in the clinic. In this review, the basic methodology of in vivo MRS is described-mainly focused on (1)H MRS of the brain-with attention to hardware requirements, patient safety, acquisition methods, data post-processing, and quantification. Furthermore, examples of clinical applications of in vivo brain MRS in two interesting fields are described. First, together with a description of the major resonances present in brain MR spectra, several examples are presented of deviations from the normal spectral pattern associated with inborn errors of metabolism. Second, through examples of MR spectra of brain tumors, it is shown that MRS can play an important role in oncology.
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Affiliation(s)
- Marinette van der Graaf
- Clinical Physics Laboratory, Department of Paediatrics 833, Radboud University Nijmegen Medical Centre, 6500 HB Nijmegen, The Netherlands.
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Klomp DWJ, Wijnen JP, Scheenen TWJ, Heerschap A. Efficient 1H to 31P polarization transfer on a clinical 3T MR system. Magn Reson Med 2009; 60:1298-305. [PMID: 19030163 DOI: 10.1002/mrm.21733] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
31P MR spectroscopy (MRS) in the detection of phosphocholine (PC), glycerolphosphocholine (GPC), phosphorylelthanolamine (PE), and glycerolphosphoethanolamine (GPE) compounds has shown clinical potential at 1.5T for several human diseases. The use of (1)H to (31)P polarization transfer can improve the sensitivity using a refocused INEPT method with a potential enhancement of 2.4 (gamma(1H)/gamma(31P)). However, in this method the (31)P signals of PE, PC, GPE, and GPC are strongly attenuated (50% or more) due to J-coupling between (31)P and (1)H that have similar magnitudes for homonuclear J-coupling constants in those metabolites. A method to cancel the homonuclear J-coupling effects in polarization transfer experiments is to apply frequency-selective refocusing pulses, which becomes feasible at 3T due to the increased chemical shift dispersion as compared to 1.5T. In this study, full (1)H to (31)P polarization transfer was realized using chemical shift selective refocusing pulses at 3T. T(1) and T(2) values for (1)H and (31)P spins of PE, PC, GPE, and GPC were measured in the human brain. A more than 2-fold signal-to-noise ratio (SNR) improvement was obtained compared to an optimized direct (31)P MRS method. As shifted RF pulses were used, this method can be applied on a broadband clinical MR system with a single RF system.
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Affiliation(s)
- D W J Klomp
- Department of Radiology, Radboud University Nijmegen Medical Center, Nijmegen, the Netherlands.
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