1
|
Buitinga M, Veeraiah P, Haans F, Schrauwen-Hinderling VB. Ectopic lipid deposition in muscle and liver, quantified by proton magnetic resonance spectroscopy. Obesity (Silver Spring) 2023; 31:2447-2459. [PMID: 37667838 DOI: 10.1002/oby.23865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 05/09/2023] [Accepted: 05/09/2023] [Indexed: 09/06/2023]
Abstract
Advances in the development of noninvasive imaging techniques have spurred investigations into ectopic lipid deposition in the liver and muscle and its implications in the development of metabolic diseases such as type 2 diabetes. Computed tomography and ultrasound have been applied in the past, though magnetic resonance-based methods are currently considered the gold standard as they allow more accurate quantitative detection of ectopic lipid stores. This review focuses on methodological considerations of magnetic resonance-based methods to image hepatic and muscle fat fractions, and it emphasizes anatomical and morphological aspects and how these may influence data acquisition, analysis, and interpretation.
Collapse
Affiliation(s)
- Mijke Buitinga
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center+, Maastricht, The Netherlands
- Department of Nutrition and Movement Sciences (NUTRIM), Maastricht University, Maastricht, The Netherlands
| | - Pandichelvam Veeraiah
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center+, Maastricht, The Netherlands
- Scannexus (Ultra-High Field Imaging Center), Maastricht, The Netherlands
- Faculty of Health Medicine and Life Sciences (FHML), Maastricht, The Netherlands
| | - Florian Haans
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center+, Maastricht, The Netherlands
| | - Vera B Schrauwen-Hinderling
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center+, Maastricht, The Netherlands
- Department of Nutrition and Movement Sciences (NUTRIM), Maastricht University, Maastricht, The Netherlands
- Institute for Clinical Diabetology, German Diabetes Center and Leibniz Center for Diabetes Research at Heinrich Heine University, Düsseldorf, Germany
| |
Collapse
|
2
|
Fellinger P, Beiglböck H, Semmler G, Pfleger L, Smajis S, Baumgartner C, Gajdosik M, Marculescu R, Vila G, Winhofer Y, Scherer T, Trauner M, Kautzky-Willer A, Krssak M, Krebs M, Wolf P. Increased GH/IGF-I Axis Activity Relates to Lower Hepatic Lipids and Phosphor Metabolism. J Clin Endocrinol Metab 2023; 108:e989-e997. [PMID: 37104943 PMCID: PMC10505545 DOI: 10.1210/clinem/dgad206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 03/25/2023] [Accepted: 04/10/2023] [Indexed: 04/29/2023]
Abstract
CONTEXT Non-alcoholic fatty liver disease (NAFLD) is a leading causes of liver-related morbidity and mortality. While data on acromegaly, a state of chronic growth hormone (GH)/insulin-like growth factor I (IGF-I) excess, suggest an inverse relationship with intrahepatic lipid (IHL) content, less is known about the impact of the GH/IGF-I axis on IHL, lipid composition, and phosphor metabolites in individuals without disorders of GH secretion. OBJECTIVE The aim was to investigate the relation between activity of the GH/IGF-I axis and IHL content and phosphor metabolism. METHODS We performed a cross-sectional study in 59 otherwise metabolically healthy individuals (30 females), of which 16 met the criteria of NAFLD with IHL of ≥5.6%. The GH/IGF-I axis was evaluated in a fasting state and during an oral glucose tolerance test (OGTT). Insulin sensitivity was estimated by validated indices. IHL, lipid composition (unsaturation index), and phosphate metabolites were analyzed by using 1H/31P magnetic resonance spectroscopy. RESULTS In the overall cohort (40.6 ± 15 years; body mass index: 24.5 ± 3 kg/m2; IGF-I: 68.0 ± 17% upper limit of normal), fasting GH (R = -0.31; P = .02), GH during oral glucose tolerance test (R = -0.51; P < .01), and IGF-I (R = -0.28; P = .03) inversely correlated with IHL. GH levels during OGTT were significantly lower in NAFLD than in controls (47.7 [22; 143] ng/mL/min vs 16.8 [7; 32] ng/mL/min; P = .003). GH/IGF-I axis activity correlated with lipid composition and with phosphor metabolites. In multiple regression analysis, the GH/IGF-I axis activity was a strong predictor for IHL and lipid composition independent from insulin sensitivity. CONCLUSION GH/IGF-I axis activity impacts hepatic lipid and phosphate metabolism in individuals without disorders in GH secretion. Lower GH axis activity is associated with higher IHL and an unfavorable lipid composition, probably mediated by changes in hepatic energy metabolism.
Collapse
Affiliation(s)
- Paul Fellinger
- Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, 1090 Vienna, Austria
| | - Hannes Beiglböck
- Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, 1090 Vienna, Austria
| | - Georg Semmler
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, 1090 Vienna, Austria
| | - Lorenz Pfleger
- Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, 1090 Vienna, Austria
- Centre of Excellence-High Field MR, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, 1090 Vienna, Austria
| | - Sabina Smajis
- Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, 1090 Vienna, Austria
| | - Clemens Baumgartner
- Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, 1090 Vienna, Austria
| | - Martin Gajdosik
- Centre of Excellence-High Field MR, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, 1090 Vienna, Austria
| | - Rodrig Marculescu
- Department of Laboratory Medicine, Medical University of Vienna, 1090 Vienna, Austria
| | - Greisa Vila
- Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, 1090 Vienna, Austria
| | - Yvonne Winhofer
- Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, 1090 Vienna, Austria
| | - Thomas Scherer
- Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, 1090 Vienna, Austria
| | - Michael Trauner
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, 1090 Vienna, Austria
| | - Alexandra Kautzky-Willer
- Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, 1090 Vienna, Austria
| | - Martin Krssak
- Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, 1090 Vienna, Austria
- Centre of Excellence-High Field MR, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, 1090 Vienna, Austria
| | - Michael Krebs
- Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, 1090 Vienna, Austria
| | - Peter Wolf
- Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, 1090 Vienna, Austria
| |
Collapse
|
3
|
Bawden SJ, Hoad C, Kaye P, Stephenson M, Dolman G, James MW, Wilkes E, Austin A, Guha IN, Francis S, Gowland P, Aithal GP. Comparing magnetic resonance liver fat fraction measurements with histology in fibrosis: the difference between proton density fat fraction and tissue mass fat fraction. MAGMA (NEW YORK, N.Y.) 2023; 36:553-563. [PMID: 36538248 PMCID: PMC10468948 DOI: 10.1007/s10334-022-01052-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 11/22/2022] [Accepted: 11/23/2022] [Indexed: 06/17/2023]
Abstract
OBJECTIVE Magnetic resonance spectroscopy (MRS) provides a powerful method of measuring fat fraction. However, previous studies have shown that MRS results give lower values compared with visual estimates from biopsies in fibrotic livers. This study investigated these discrepancies and considered whether a tissue water content correction, as assessed by MRI relaxometry, could provide better agreement. MATERIALS AND METHODS 110 patients were scanned in a 1.5 T Philips scanner and biopsies were obtained. Multiple echo MRS (30 × 30 × 30 mm volume) was used to determine Proton Density Fat Fraction (PDFF). Biopsies were assessed by visual assessment for fibrosis and steatosis grading. Digital image analysis (DIA) was also used to quantify fat fraction within tissue samples. T1 relaxation times were then used to estimate tissue water content to correct PDFF for confounding factors. RESULTS PDFF values across the four visually assessed steatosis grades were significantly less in the higher fibrosis group (F3-F4) compared to the lower fibrosis group (F0-F2). The slope of the linear regression of PDFF vs DIA fat fraction was ~ 1 in the low fibrosis group and 0.77 in the high fibrosis group. Correcting for water content based on T1 increased the gradient but it did not reach unity. DISCUSSION In fibrotic livers, PDFF underestimated fat fraction compared to DIA methods. Values were improved by applying a water content correction, but fat fractions were still underestimated.
Collapse
Affiliation(s)
- Stephen James Bawden
- Nottingham Digestive Diseases Centre, NIHR Nottingham Biomedical Research Centre at the Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, NG7 2RD, UK.
- Sir Peter Mansfield Imaging Centre, SPMIC, University Park, Physics and Astronomy, University of Nottingham, Nottingham, UK.
| | - Caroline Hoad
- Nottingham Digestive Diseases Centre, NIHR Nottingham Biomedical Research Centre at the Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, NG7 2RD, UK
| | - Philip Kaye
- Nottingham Digestive Diseases Centre, NIHR Nottingham Biomedical Research Centre at the Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, NG7 2RD, UK
- Department of Cellular Pathology, Nottingham University Hospitals NHS Trust, Nottingham, UK
| | - Mary Stephenson
- Clinical Imaging Research Centre (CIRC), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Grace Dolman
- Nottingham Digestive Diseases Centre, NIHR Nottingham Biomedical Research Centre at the Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, NG7 2RD, UK
| | - Martin W James
- Nottingham Digestive Diseases Centre, NIHR Nottingham Biomedical Research Centre at the Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, NG7 2RD, UK
| | - Emilie Wilkes
- Nottingham Digestive Diseases Centre, NIHR Nottingham Biomedical Research Centre at the Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, NG7 2RD, UK
| | | | - Indra Neil Guha
- Nottingham Digestive Diseases Centre, NIHR Nottingham Biomedical Research Centre at the Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, NG7 2RD, UK
| | - Susan Francis
- Sir Peter Mansfield Imaging Centre, SPMIC, University Park, Physics and Astronomy, University of Nottingham, Nottingham, UK
| | - Penny Gowland
- Sir Peter Mansfield Imaging Centre, SPMIC, University Park, Physics and Astronomy, University of Nottingham, Nottingham, UK
| | - Guruprasad P Aithal
- Nottingham Digestive Diseases Centre, NIHR Nottingham Biomedical Research Centre at the Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, NG7 2RD, UK
| |
Collapse
|
4
|
Seifeldein GS, Hassan EA, Imam HM, Makboul R, Idriss NK, Gaber MA, Elkady RM. Quantitative MDCT and MRI assessment of hepatic steatosis in genotype 4 chronic hepatitis C patients with fibrosis. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2021. [DOI: 10.1186/s43055-021-00590-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Hepatic steatosis has been shown to worsen the course of liver disease in chronic hepatitis C (CHC) patients, and it may reduce the efficacy of antiviral therapy and accelerate disease progression. In this cross-sectional study, we aimed to evaluate the role of multidetector computed tomography and magnetic resonance imaging (MRI) in the quantitative assessment and grading of hepatic steatosis to evaluate the association between hepatic steatosis and fibrosis in Egyptian genotype 4-CHC (G4-CHC) patients.
Results
Histopathological hepatic steatosis was found in 70.3% of 155 patients. No correlation was found between the CT ratio and pathological hepatic steatosis. Proton density fat fraction, T1-fat fraction, and fat percentage correlated with histological steatosis grading (r = 0.953, p < 0.001; r = 0.380, p = 0.027 and r = 0.384, p = 0.025, respectively). An agreement between steatosis grading by histology and 1H-MRS was found in 74.2% of patients. Compared to other MRI modalities, proton density fat fraction had the highest area under the receiver operating characteristic curve (AUC), with 0.910, 0.931, and 0.975 for mild, moderate, and severe steatosis, respectively. The cutoff with the best ability to predict steatosis was > 4.95 for a proton density fat fraction (AUC = 0.958) with 95.8% sensitivity, 90% specificity, 78.5% positive predictive value, and 96.1% negative predictive value.
Conclusion
1H-MRS had good diagnostic performance in predicting hepatic steatosis in G4-CHC patients, and hence, it may offer a useful noninvasive quantitative modality for grading steatosis with clinical applicability, especially in those where a liver biopsy cannot be done.
Collapse
|
5
|
Pasanta D, Htun KT, Pan J, Tungjai M, Kaewjaeng S, Kim H, Kaewkhao J, Kothan S. Magnetic Resonance Spectroscopy of Hepatic Fat from Fundamental to Clinical Applications. Diagnostics (Basel) 2021; 11:diagnostics11050842. [PMID: 34067193 PMCID: PMC8151733 DOI: 10.3390/diagnostics11050842] [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: 04/22/2021] [Revised: 04/29/2021] [Accepted: 05/06/2021] [Indexed: 02/06/2023] Open
Abstract
The number of individuals suffering from fatty liver is increasing worldwide, leading to interest in the noninvasive study of liver fat. Magnetic resonance spectroscopy (MRS) is a powerful tool that allows direct quantification of metabolites in tissue or areas of interest. MRS has been applied in both research and clinical studies to assess liver fat noninvasively in vivo. MRS has also demonstrated excellent performance in liver fat assessment with high sensitivity and specificity compared to biopsy and other imaging modalities. Because of these qualities, MRS has been generally accepted as the reference standard for the noninvasive measurement of liver steatosis. MRS is an evolving technique with high potential as a diagnostic tool in the clinical setting. This review aims to provide a brief overview of the MRS principle for liver fat assessment and its application, and to summarize the current state of MRS study in comparison to other techniques.
Collapse
Affiliation(s)
- Duanghathai Pasanta
- Center of Radiation Research and Medical Imaging, Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand; (D.P.); (K.T.H.); (J.P.); (M.T.); (S.K.)
| | - Khin Thandar Htun
- Center of Radiation Research and Medical Imaging, Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand; (D.P.); (K.T.H.); (J.P.); (M.T.); (S.K.)
| | - Jie Pan
- Center of Radiation Research and Medical Imaging, Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand; (D.P.); (K.T.H.); (J.P.); (M.T.); (S.K.)
- Shandong Provincial Key Laboratory of Animal Resistant Biology, College of Life Sciences, Shandong Normal University, Jinan 250014, China
| | - Montree Tungjai
- Center of Radiation Research and Medical Imaging, Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand; (D.P.); (K.T.H.); (J.P.); (M.T.); (S.K.)
| | - Siriprapa Kaewjaeng
- Center of Radiation Research and Medical Imaging, Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand; (D.P.); (K.T.H.); (J.P.); (M.T.); (S.K.)
| | - Hongjoo Kim
- Department of Physics, Kyungpook National University, Daegu 41566, Korea;
| | - Jakrapong Kaewkhao
- Center of Excellence in Glass Technology and Materials Science (CEGM), Nakhon Pathom Rajabhat University, Nakhon Pathom 73000, Thailand;
| | - Suchart Kothan
- Center of Radiation Research and Medical Imaging, Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand; (D.P.); (K.T.H.); (J.P.); (M.T.); (S.K.)
- Correspondence: ; Tel.: +66-5394-9213
| |
Collapse
|
6
|
Kořínek R, Pfleger L, Eckstein K, Beiglböck H, Robinson SD, Krebs M, Trattnig S, Starčuk Z, Krššák M. Feasibility of Hepatic Fat Quantification Using Proton Density Fat Fraction by Multi-Echo Chemical-Shift-Encoded MRI at 7T. FRONTIERS IN PHYSICS 2021; 9:665562. [PMID: 34849373 PMCID: PMC7612048 DOI: 10.3389/fphy.2021.665562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Fat fraction quantification and assessment of its distribution in the hepatic tissue become more important with the growing epidemic of obesity, and the increasing prevalence of diabetes mellitus type 2 and non-alcoholic fatty liver disease. At 3Tesla, the multi-echo, chemical-shift-encoded magnetic resonance imaging (CSE-MRI)-based acquisition allows the measurement of proton density fat-fraction (PDFF) even in clinical protocols. Further improvements in SNR can be achieved by the use of phased array coils and increased static magnetic field. The purpose of the study is to evaluate the feasibility of PDFF imaging using a multi-echo CSE-MRI technique at ultra-high magnetic field (7Tesla). Thirteen volunteers (M/F) with a broad range of age, body mass index, and hepatic PDFF were measured at 3 and 7T by multi-gradient-echo MRI and single-voxel spectroscopy MRS. All measurements were performed in breath-hold (exhalation); the MRI protocols were optimized for a short measurement time, thus minimizing motion-related problems. 7T data were processed off-line using Matlab® (MRI:multi-gradient-echo) and jMRUI (MRS), respectively. For quantitative validation of the PDFF results, a similar protocol was performed at 3T, including on-line data processing provided by the system manufacturer, and correlation analyses between 7 and 3T data were performed off-line. The multi-echo CSE-MRI measurements at 7T with a phased-array coil configuration and an optimal post-processing yielded liver volume coverage ranging from 30 to 90% for high- and low-BMI subjects, respectively. PDFFs ranged between 1 and 20%. We found significant correlations between 7T MRI and -MRS measurements (R2 ≅ 0.97; p < 0.005), and between MRI-PDFF at 7T and 3T fields (R2 ≅ 0.94; p < 0.005) in the evaluated volumes. Based on the measurements and analyses performed, the multi-echo CSE-MRI method using a 32-channel coil at 7T showed its aptitude for MRI-based quantitation of PDFF in the investigated volumes. The results are the first step toward qMRI of the whole liver at 7T with further improvements in hardware.
Collapse
Affiliation(s)
- Radim Kořínek
- Magnetic Resonance group, Institute of Scientific Instruments of the Czech Academy of Sciences, Brno, Czechia
| | - Lorenz Pfleger
- Division of Endocrinology and Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Korbinian Eckstein
- Department of Biomedical Imaging and Image-Guided Therapy, High-Field Magnetic Resonance Centre, Medical University of Vienna, Vienna, Austria
| | - Hannes Beiglböck
- Division of Endocrinology and Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Simon Daniel Robinson
- Department of Biomedical Imaging and Image-Guided Therapy, High-Field Magnetic Resonance Centre, Medical University of Vienna, Vienna, Austria
| | - Michael Krebs
- Division of Endocrinology and Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Siegfried Trattnig
- Department of Biomedical Imaging and Image-Guided Therapy, High-Field Magnetic Resonance Centre, Medical University of Vienna, Vienna, Austria
- Christian Doppler Laboratory for Clinical Molecular Imaging, CD Laboratory for Clinical Molecular MR Imaging (MOLIMA), Medical University of Vienna, Vienna, Austria
| | - Zenon Starčuk
- Magnetic Resonance group, Institute of Scientific Instruments of the Czech Academy of Sciences, Brno, Czechia
| | - Martin Krššák
- Division of Endocrinology and Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
- Department of Biomedical Imaging and Image-Guided Therapy, High-Field Magnetic Resonance Centre, Medical University of Vienna, Vienna, Austria
- Christian Doppler Laboratory for Clinical Molecular Imaging, CD Laboratory for Clinical Molecular MR Imaging (MOLIMA), Medical University of Vienna, Vienna, Austria
| |
Collapse
|
7
|
Juchem C, Cudalbu C, de Graaf RA, Gruetter R, Henning A, Hetherington HP, Boer VO. B 0 shimming for in vivo magnetic resonance spectroscopy: Experts' consensus recommendations. NMR IN BIOMEDICINE 2021; 34:e4350. [PMID: 32596978 DOI: 10.1002/nbm.4350] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 05/14/2020] [Accepted: 05/19/2020] [Indexed: 05/07/2023]
Abstract
Magnetic resonance spectroscopy (MRS) and spectroscopic imaging (MRSI) allow the chemical analysis of physiological processes in vivo and provide powerful tools in the life sciences and for clinical diagnostics. Excellent homogeneity of the static B0 magnetic field over the object of interest is essential for achieving high-quality spectral results and quantitative metabolic measurements. The experimental minimization of B0 variation is performed in a process called B0 shimming. In this article, we summarize the concepts of B0 field shimming using spherical harmonic shimming techniques, specific strategies for B0 homogenization and crucial factors to consider for implementation and use in both brain and body. In addition, experts' recommendations are provided for minimum requirements for B0 shim hardware and evaluation criteria for the primary outcome of adequate B0 shimming for MRS and MRSI, such as the water spectroscopic linewidth.
Collapse
Affiliation(s)
- Christoph Juchem
- Departments of Biomedical Engineering and Radiology, Columbia University, New York, New York
| | - Cristina Cudalbu
- Centre d'Imagerie Biomedicale (CIBM), Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Robin A de Graaf
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, Connecticut
| | - Rolf Gruetter
- Laboratory for Functional and Metabolic Imaging, Center for Biomedical Imaging, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland
| | - Anke Henning
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas
- Max Planck Institute for Biological Cybernetics, Tuebingen, Germany
| | | | - Vincent O Boer
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
| |
Collapse
|
8
|
Bakermans AJ, Boekholdt SM, de Vries DK, Reckman YJ, Farag ES, de Heer P, Uthman L, Denis SW, Zuurbier CJ, Houtkooper RH, Koolbergen DR, Kluin J, Planken RN, Lamb HJ, Webb AG, Strijkers GJ, Beard DA, Jeneson JAL, Nederveen AJ. Quantification of Myocardial Creatine and Triglyceride Content in the Human Heart: Precision and Accuracy of in vivo Proton Magnetic Resonance Spectroscopy. J Magn Reson Imaging 2021; 54:411-420. [PMID: 33569824 PMCID: PMC8277665 DOI: 10.1002/jmri.27531] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 01/10/2021] [Accepted: 01/11/2021] [Indexed: 12/26/2022] Open
Abstract
Background Proton magnetic resonance spectroscopy (1H‐MRS) of the human heart is deemed to be a quantitative method to investigate myocardial metabolite content, but thorough validations of in vivo measurements against invasive techniques are lacking. Purpose To determine measurement precision and accuracy for quantifications of myocardial total creatine and triglyceride content with localized 1H‐MRS. Study type Test–retest repeatability and measurement validation study. Subjects Sixteen volunteers and 22 patients scheduled for open‐heart aortic valve replacement or septal myectomy. Field Strength/Sequence Prospectively ECG‐triggered respiratory‐gated free‐breathing single‐voxel point‐resolved spectroscopy (PRESS) sequence at 3 T. Assessment Myocardial total creatine and triglyceride content were quantified relative to the total water content by fitting the 1H‐MR spectra. Precision was assessed with measurement repeatability. Accuracy was assessed by validating in vivo 1H‐MRS measurements against biochemical assays in myocardial tissue from the same subjects. Statistical Tests Intrasession and intersession repeatability was assessed using Bland–Altman analyses. Agreement between 1H‐MRS measurements and biochemical assay was tested with regression analyses. Results The intersession repeatability coefficient for myocardial total creatine content was 41.8% with a mean value of 0.083% ± 0.020% of the total water signal, and 36.7% for myocardial triglyceride content with a mean value of 0.35% ± 0.13% of the total water signal. Ex vivo myocardial total creatine concentrations in tissue samples correlated with the in vivo myocardial total creatine content measured with 1H‐MRS: n = 22, r = 0.44; P < 0.05. Likewise, ex vivo myocardial triglyceride concentrations correlated with the in vivo myocardial triglyceride content: n = 20, r = 0.50; P < 0.05. Data Conclusion We validated the use of localized 1H‐MRS of the human heart at 3 T for quantitative assessments of in vivo myocardial tissue metabolite content by estimating the measurement precision and accuracy. Level of Evidence 2 Technical Efficacy Stage 2
Collapse
Affiliation(s)
- Adrianus J Bakermans
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - S Matthijs Boekholdt
- Department of Cardiology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Dylan K de Vries
- Department of Experimental Cardiology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Yolan J Reckman
- Department of Experimental Cardiology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Emile S Farag
- Department of Cardiothoracic Surgery, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Paul de Heer
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands.,C.J. Gorter Center for High Field MR, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Laween Uthman
- Laboratory of Experimental Intensive Care and Anesthesiology, Department of Anesthesiology, Amsterdam Cardiovascular Sciences, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Simone W Denis
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam Cardiovascular Sciences, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Coert J Zuurbier
- Laboratory of Experimental Intensive Care and Anesthesiology, Department of Anesthesiology, Amsterdam Cardiovascular Sciences, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Riekelt H Houtkooper
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology Endocrinology Metabolism, Amsterdam Cardiovascular Sciences, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - David R Koolbergen
- Department of Cardiothoracic Surgery, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Jolanda Kluin
- Department of Cardiothoracic Surgery, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - R Nils Planken
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Hildo J Lamb
- Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Andrew G Webb
- C.J. Gorter Center for High Field MR, Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Gustav J Strijkers
- Biomedical Engineering and Physics, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| | - Daniel A Beard
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Jeroen A L Jeneson
- Neuroimaging Center, Department of Neuroscience, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Aart J Nederveen
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
| |
Collapse
|
9
|
Kořínek R, Gajdošík M, Trattnig S, Starčuk Z, Krššák M. Low-level fat fraction quantification at 3 T: comparative study of different tools for water-fat reconstruction and MR spectroscopy. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2020; 33:455-468. [PMID: 31980962 DOI: 10.1007/s10334-020-00825-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 12/12/2019] [Accepted: 01/03/2020] [Indexed: 12/22/2022]
Abstract
OBJECTIVES Chemical Shift Encoded Magnetic Resonance Imaging (CSE-MRI)-based quantification of low-level (< 5% of proton density fat fraction-PDFF) fat infiltration requires highly accurate data reconstruction for the assessment of hepatic or pancreatic fat accumulation in diagnostics and biomedical research. MATERIALS AND METHODS We compare three software tools available for water/fat image reconstruction and PDFF quantification with MRS as the reference method. Based on the algorithm exploited in the tested software, the accuracy of fat fraction quantification varies. We evaluate them in phantom and in vivo MRS and MRI measurements. RESULTS The signal model of Intralipid 20% emulsion used for phantoms was established for 3 T and 9.4 T fields. In all cases, we noticed a high coefficient of determination (R-squared) between MRS and MRI-PDFF measurements: in phantoms <0.9924-0.9990>; and in vivo <0.8069-0.9552>. Bland-Altman analysis was applied to phantom and in vivo measurements. DISCUSSION Multi-echo MRI in combination with an advanced algorithm including multi-peak spectrum modeling appears as a valuable and accurate method for low-level PDFF quantification over large FOV in high resolution, and is much faster than MRS methods. The graph-cut algorithm (GC) showed the fewest water/fat swaps in the PDFF maps, and hence stands out as the most robust method of those tested.
Collapse
Affiliation(s)
- Radim Kořínek
- Institute of Scientific Instruments of the CAS, Kralovopolska 147, 612 64, Brno, Czech Republic.
| | - Martin Gajdošík
- Department of Biomedical Imaging and Image-Guided Therapy, High-Field MR Centre, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria.,Department of Biomedical Engineering, Columbia University Fu Foundation School of Engineering and Applied Science, 1210 Amsterdam Ave, New York, NY, 10027, USA
| | - Siegfried Trattnig
- Department of Biomedical Imaging and Image-Guided Therapy, High-Field MR Centre, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria.,Christian Doppler Laboratory for Clinical Molecular Imaging, MOLIMA, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Zenon Starčuk
- Institute of Scientific Instruments of the CAS, Kralovopolska 147, 612 64, Brno, Czech Republic
| | - Martin Krššák
- Department of Biomedical Imaging and Image-Guided Therapy, High-Field MR Centre, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria.,Christian Doppler Laboratory for Clinical Molecular Imaging, MOLIMA, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria.,Division of Endocrinology and Metabolism, Department of Medicine III, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| |
Collapse
|
10
|
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: 267] [Impact Index Per Article: 44.5] [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
|
11
|
Kosi-Trebotic L, Thomas A, Harreiter J, Chmelik M, Trattnig S, Kautzky-Willer A. Gliptin therapy reduces hepatic and myocardial fat in type 2 diabetic patients. Eur J Clin Invest 2017; 47:829-838. [PMID: 28815568 DOI: 10.1111/eci.12817] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 08/13/2017] [Indexed: 12/14/2022]
Abstract
BACKGROUND Increased hepatic fat and cardiac fat are common in patients with type 2 diabetes mellitus (T2DM) and are associated with a greater risk of liver fibrosis and cardiovascular (CV) events. Sex-specific differences of dipeptidyl peptidase-four (DPP-4) inhibitor effects on hepatic (HCL) and myocardial fat content (MYCL) have not yet been evaluated. METHOD Forty-one T2DM patients (20 male, 21 female) received a gliptin add-on therapy if HbA1c goals were not reached under metformin monotherapy. They underwent cardiac and liver magnetic resonance tomography and spectroscopy before and 6 months after therapy initiation. Plasma samples were analysed for the growth differentiation factor 15 (GDF-15), a novel marker for cardiovascular risk. RESULTS Thirty-eight patients on gliptin therapy completed the study. We observed a positive correlation between MYCL and HCL before therapy (R = 0·41, P = 0·05). After 6 months of therapy, we noticed a significant weight reduction in women only (P = 0·02) whereas waist circumference decreased similarly in both sexes. HbA1c sunk significantly in both sexes (P = 0·002). HCL decreased significantly (P = 0·0004), with women featuring higher basal HCL (P < 0·05). MYCL decreased in women only (P = 0·01) and GDF-15 comparably in both sexes (P < 0·05). CONCLUSIONS 6 months of DPP-4-therapy led to a significant overall decrease in HCL and body weight such as a reduction of MYCL only in women. This preliminary data set could implicate that gliptin may be a feasible therapy option in fatty liver patients with diabetes potentially including positive effects on cardiovascular function particularly in women.
Collapse
Affiliation(s)
- Lana Kosi-Trebotic
- Gender Medicine Unit, Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Anita Thomas
- Gender Medicine Unit, Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Jürgen Harreiter
- Gender Medicine Unit, Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Marek Chmelik
- Department of Radiodiagnostics, Centre of Excellence, High-Field MR, Medical University of Vienna, Vienna, Austria
| | - Siegfried Trattnig
- Department of Radiodiagnostics, Centre of Excellence, High-Field MR, Medical University of Vienna, Vienna, Austria
| | - Alexandra Kautzky-Willer
- Gender Medicine Unit, Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
12
|
Traussnigg S, Kienbacher C, Gajdošík M, Valkovič L, Halilbasic E, Stift J, Rechling C, Hofer H, Steindl‐Munda P, Ferenci P, Wrba F, Trattnig S, Krššák M, Trauner M. Ultra-high-field magnetic resonance spectroscopy in non-alcoholic fatty liver disease: Novel mechanistic and diagnostic insights of energy metabolism in non-alcoholic steatohepatitis and advanced fibrosis. Liver Int 2017; 37:1544-1553. [PMID: 28544208 PMCID: PMC5638103 DOI: 10.1111/liv.13451] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND & AIMS With the rising prevalence of non-alcoholic fatty liver disease (NAFLD) and steatohepatitis (NASH) non-invasive tools obtaining pathomechanistic insights to improve risk stratification are urgently needed. We therefore explored high- and ultra-high-field magnetic resonance spectroscopy (MRS) to obtain novel mechanistic and diagnostic insights into alterations of hepatic lipid, cell membrane and energy metabolism across the spectrum of NAFLD. METHODS MRS and liver biopsy were performed in 30 NAFLD patients with NAFL (n=8) or NASH (n=22). Hepatic lipid content and composition were measured using 3-Tesla proton (1 H)-MRS. 7-Tesla phosphorus (31 P)-MRS was applied to determine phosphomonoester (PME) including phosphoethanolamine (PE), phosphodiester (PDE) including glycerophosphocholine (GPC), phosphocreatine (PCr), nicotinamide adenine dinucleotide phosphate (NADPH), inorganic phosphate (Pi), γ-ATP and total phosphorus (TP). Saturation transfer technique was used to quantify hepatic ATP flux. RESULTS Hepatic steatosis in 1 H-MRS highly correlated with histology (P<.001) showing higher values in NASH than NAFL (P<.001) without differences in saturated or unsaturated fatty acid indices. PE/TP ratio increased with advanced fibrosis (F3/4) (P=.002) whereas GPC/PME+PDE decreased (P=.05) compared to no/mild fibrosis (F0-2). γ-ATP/TP was lower in advanced fibrosis (P=.049), while PCr/TP increased (P=.01). NADPH/TP increased with higher grades of ballooning (P=.02). Pi-to-ATP exchange rate constant (P=.003) and ATP flux (P=.001) were lower in NASH than NAFL. CONCLUSIONS Ultra-high-field MRS, especially saturation transfer technique uncovers changes in energy metabolism including dynamic ATP flux in inflammation and fibrosis in NASH. Non-invasive profiling by MRS appears feasible and may assist further mechanistic and therapeutic studies in NAFLD/NASH.
Collapse
Affiliation(s)
- Stefan Traussnigg
- Division of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - Christian Kienbacher
- Division of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - Martin Gajdošík
- High‐Field MR CenterDepartment of Biomedical Imaging and Image‐guided TherapyMedical University of ViennaViennaAustria,Christian Doppler Laboratory for Clinical Molecular MR ImagingViennaAustria
| | - Ladislav Valkovič
- High‐Field MR CenterDepartment of Biomedical Imaging and Image‐guided TherapyMedical University of ViennaViennaAustria,Christian Doppler Laboratory for Clinical Molecular MR ImagingViennaAustria,Department of Imaging MethodsInstitute of Measurement ScienceSlovak Academy of SciencesBratislavaSlovakia
| | - Emina Halilbasic
- Division of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - Judith Stift
- Department of Clinical PathologyMedical University of ViennaViennaAustria
| | - Christian Rechling
- Division of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - Harald Hofer
- Division of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - Petra Steindl‐Munda
- Division of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - Peter Ferenci
- Division of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - Fritz Wrba
- Department of Clinical PathologyMedical University of ViennaViennaAustria
| | - Siegfried Trattnig
- High‐Field MR CenterDepartment of Biomedical Imaging and Image‐guided TherapyMedical University of ViennaViennaAustria,Christian Doppler Laboratory for Clinical Molecular MR ImagingViennaAustria
| | - Martin Krššák
- High‐Field MR CenterDepartment of Biomedical Imaging and Image‐guided TherapyMedical University of ViennaViennaAustria,Christian Doppler Laboratory for Clinical Molecular MR ImagingViennaAustria,Division of Endocrinology and MetabolismDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - Michael Trauner
- Division of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| |
Collapse
|
13
|
Chabanova E, Fonvig CE, Bøjsøe C, Holm JC, Thomsen HS. 1H MRS Assessment of Hepatic Fat Content: Comparison Between Normal- and Excess-weight Children and Adolescents. Acad Radiol 2017; 24:982-987. [PMID: 28462823 DOI: 10.1016/j.acra.2017.02.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 02/13/2017] [Accepted: 02/14/2017] [Indexed: 12/31/2022]
Abstract
RATIONALE AND OBJECTIVES The purpose of the present study was to obtain a cutoff value of liver fat content for the diagnosis of hepatic steatosis by comparing magnetic resonance (MR) spectroscopy results in children and adolescents with normal and excess weight. MATERIALS AND METHODS The study included 420 children and adolescents (91 normal-weight, 99 overweight, and 230 obese) 8-18 years of age. Proton magnetic resonance spectroscopy was performed with a 3T MR system using point resolved spectroscopy sequence with series echo times. RESULTS The mean absolute mass concentration of liver fat was obtained: 0.5 ± 0.04% in normal-weight boys; 0.5 ± 0.03% in normal-weight girls; 0.9 ± 0.16% in boys with overweight; 1.1 ± 0.24% in girls with overweight; 1.7 ± 0.24% in boys with obesity; and 1.4 ± 0.21% in girls with obesity. The cutoff value of absolute mass concentration of liver fat for hepatic steatosis was found to be 1.5%. Based on this cutoff value, hepatic steatosis was diagnosed in 16% of boys with overweight, 11% of girls with overweight, 32% of boys with obesity, and 27% of girls with obesity. CONCLUSIONS Proton magnetic resonance spectroscopy was successfully applied to obtain the cutoff value of absolute mass concentration of liver fat for the diagnosis of hepatic steatosis in children and adolescents. Children and adolescents with obesity have higher risk of hepatic steatosis than their peers with overweight.
Collapse
Affiliation(s)
- Elizaveta Chabanova
- Department of Diagnostic Radiology, Copenhagen University Hospital Herlev Gentofte, Herlev Ringvej 75, DK-2730 Herlev, Denmark.
| | - Cilius Esmann Fonvig
- The Children's Obesity Clinic, Department of Pediatrics, Copenhagen University Hospital Holbæk, Holbæk, Denmark; The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, University of Copenhagen, Copenhagen, Denmark
| | - Christine Bøjsøe
- The Children's Obesity Clinic, Department of Pediatrics, Copenhagen University Hospital Holbæk, Holbæk, Denmark; The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, University of Copenhagen, Copenhagen, Denmark
| | - Jens-Christian Holm
- The Children's Obesity Clinic, Department of Pediatrics, Copenhagen University Hospital Holbæk, Holbæk, Denmark; The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, University of Copenhagen, Copenhagen, Denmark; Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Henrik S Thomsen
- Department of Diagnostic Radiology, Copenhagen University Hospital Herlev Gentofte, Herlev Ringvej 75, DK-2730 Herlev, Denmark; Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
14
|
Weis J, Kullberg J, Ahlström H. Multiple breath-hold proton spectroscopy of human liver at 3T: Relaxation times and concentrations of glycogen, choline, and lipids. J Magn Reson Imaging 2017; 47:410-417. [PMID: 28419608 DOI: 10.1002/jmri.25734] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 03/29/2017] [Indexed: 01/17/2023] Open
Abstract
PURPOSE To evaluate the feasibility of an expiration multiple breath-hold 1 H-MRS technique to measure glycogen (Glycg), choline-containing compounds (CCC), and lipid relaxation times T1 , T2 , and their concentrations in normal human liver. MATERIALS AND METHODS Thirty healthy volunteers were recruited. Experiments were performed at 3T. Multiple expiration breath-hold single-voxel point-resolved spectroscopy (PRESS) technique was used for localization. Water-suppressed spectra were used for the estimation of Glycg, CCC, lipid methylene (CH2 )n relaxation times and concentrations. Residual water lines were removed by the Hankel Lanczos singular value decomposition filter. After phase correction and frequency alignment, spectra were averaged and processed by LCModel. Summed signals of Glycg resonances H2H4', H3, and H5 between 3.6 and 4 ppm were used to estimate their apparent relaxation times and concentration. Glycg, CCC, and lipid content were estimated from relaxation corrected spectral intensity ratios to unsuppressed water line. RESULTS Relaxation times were measured for liver Glycg (T1 , 892 ± 126 msec; T2 , 13 ± 4 msec), CCC (T1 , 842 ± 75 msec; T2 , 50 ± 5 msec), lipid (CH2 )n (T1 , 402 ± 19 msec; T2 , 52 ± 3 msec), and water (T1 , 990 ± 89 msec; T2 , 30 ± 2 msec). Mean CCC and lipid concentrations of healthy liver were 7.8 ± 1.3 mM and 15.8 ± 23.6 mM, respectively. Glycg content was found lower in the morning (48 ± 21 mM) compared to the afternoon (145 ± 50 mM). CONCLUSION Multiple breath-hold 1 H-MRS together with dedicated postprocessing is a feasible technique for the quantification of liver Glycg, CCC, and lipid relaxation times and concentrations. LEVEL OF EVIDENCE 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:410-417.
Collapse
Affiliation(s)
- Jan Weis
- Department of Medical Physics, Uppsala University Hospital, Uppsala, Sweden.,Department of Radiology, Uppsala University Hospital, Uppsala, Sweden
| | - Joel Kullberg
- Department of Radiology, Uppsala University Hospital, Uppsala, Sweden
| | - Håkan Ahlström
- Department of Radiology, Uppsala University Hospital, Uppsala, Sweden
| |
Collapse
|
15
|
Krishan S, Jain D, Bathina Y, Kale A, Saraf N, Saigal S, Choudhary N, Baijal S, Soin A. Non-invasive quantification of hepatic steatosis in living, related liver donors using dual-echo Dixon imaging and single-voxel proton spectroscopy. Clin Radiol 2016; 71:58-63. [DOI: 10.1016/j.crad.2015.10.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 09/30/2015] [Accepted: 10/05/2015] [Indexed: 01/01/2023]
|
16
|
Coum A, Noury F, Bannier E, Begriche K, Fromenty B, Gandon Y, Saint-Jalmes H, Gambarota G. The effect of water suppression on the hepatic lipid quantification, as assessed by the LCModel, in a preclinical and clinical scenario. MAGMA (NEW YORK, N.Y.) 2015; 29:29-37. [PMID: 26590825 DOI: 10.1007/s10334-015-0508-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 11/03/2015] [Accepted: 11/04/2015] [Indexed: 01/07/2023]
Abstract
OBJECTIVE To investigate the effect of water suppression on the hepatic lipid quantification, using the LCModel. MATERIALS AND METHODS MR spectra with and without water suppression were acquired in the liver of mice at 4.7 T and patients at 3 T, and processed with the LCModel. The Cramér-Rao Lower Bound (CRLB) values of the seven lipid resonances were determined to assess the impact of water suppression on hepatic lipid quantification. A paired t test was used for comparison between the CRLBs obtained with and without water suppression. RESULTS For the preclinical data, in the high (low) fat fraction subset an overall impairment in hepatic lipid quantification, i.e. an increase of CRLBs (no significant change of CRLBs) was observed in spectra acquired with water suppression. For the clinical data, there were no substantial changes in the CRLB with water suppression. Because (1) the water suppression does not overall improve the quantification of the lipid resonances and (2) the MR spectrum without water suppression is always acquired for fat fraction calculation, the optimal data-acquisition strategy for liver MRS is to acquire only the MR spectrum without water suppression. CONCLUSION For quantification of hepatic lipid resonances, it is advantageous to perform MR spectroscopy without water suppression in a clinical and preclinical scenario (at moderate fields).
Collapse
Affiliation(s)
- Amandine Coum
- LTSI, Laboratoire du Traitement du Signal et de l'Image, Université de Rennes 1, 35043, Rennes Cedex, France. .,INSERM, UMR 1099, Université de Rennes 1, 35000, Rennes, France.
| | - Fanny Noury
- LTSI, Laboratoire du Traitement du Signal et de l'Image, Université de Rennes 1, 35043, Rennes Cedex, France.,INSERM, UMR 1099, Université de Rennes 1, 35000, Rennes, France
| | - Elise Bannier
- Département de Radiologie, CHU de Rennes, 35000, Rennes, France
| | | | | | - Yves Gandon
- Département de Radiologie, CHU de Rennes, 35000, Rennes, France
| | - Hervé Saint-Jalmes
- LTSI, Laboratoire du Traitement du Signal et de l'Image, Université de Rennes 1, 35043, Rennes Cedex, France.,INSERM, UMR 1099, Université de Rennes 1, 35000, Rennes, France.,CRLCC, Centre Eugène Marquis, 35000, Rennes, France
| | - Giulio Gambarota
- LTSI, Laboratoire du Traitement du Signal et de l'Image, Université de Rennes 1, 35043, Rennes Cedex, France.,INSERM, UMR 1099, Université de Rennes 1, 35000, Rennes, France
| |
Collapse
|
17
|
Gajdošík M, Chadzynski GL, Hangel G, Mlynárik V, Chmelík M, Valkovič L, Bogner W, Pohmann R, Scheffler K, Trattnig S, Krššák M. Ultrashort-TE stimulated echo acquisition mode (STEAM) improves the quantification of lipids and fatty acid chain unsaturation in the human liver at 7 T. NMR IN BIOMEDICINE 2015; 28:1283-1293. [PMID: 26313737 DOI: 10.1002/nbm.3382] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Revised: 07/15/2015] [Accepted: 07/24/2015] [Indexed: 06/04/2023]
Abstract
Ultrahigh-field, whole-body MR systems increase the signal-to-noise ratio (SNR) and improve the spectral resolution. Sequences with a short TE allow fast signal acquisition with low signal loss as a result of spin-spin relaxation. This is of particular importance in the liver for the precise quantification of the hepatocellular content of lipids (HCL). In this study, we introduce a spoiler Gradient-switching Ultrashort STimulated Echo AcqUisition (GUSTEAU) sequence, which is a modified version of a stimulated echo acquisition mode (STEAM) sequence, with a minimum TE of 6 ms. With the high spectral resolution at 7 T, the efficient elimination of water sidebands and the post-processing suppression of the water signal, we estimated the composition of fatty acids (FAs) via the detection of the olefinic lipid resonance and calculated the unsaturation index (UI) of hepatic FAs. The performance of the GUSTEAU sequence for the assessment of UI was validated against oil samples and provided excellent results in agreement with the data reported in the literature. When measuring HCL with GUSTEAU in 10 healthy volunteers, there was a high correlation between the results obtained at 7 and 3 T (R(2) = 0.961). The test-retest measurements yielded low coefficients of variation for HCL (4 ± 3%) and UI (11 ± 8%) when measured with the GUSTEAU sequence at 7 T. A negative correlation was found between UI and HCL (n = 10; p < 0.033). The ultrashort TE MRS sequence (GUSTEAU; TE = 6 ms) provided high repeatability for the assessment of HCL. The improved spectral resolution at 7 T with the elimination of water sidebands and the offline water subtraction also enabled an assessment of the unsaturation of FAs. This all highlights the potential use of this MRS acquisition scheme for studies of hepatic lipid composition in vivo.
Collapse
Affiliation(s)
- Martin Gajdošík
- High-Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
- Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna, Austria
| | - Grzegorz L Chadzynski
- Department of Biomedical Magnetic Resonance, University of Tübingen, Tübingen, Germany
- High-Field Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tübingen, Germany
| | - Gilbert Hangel
- High-Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Vladimír Mlynárik
- High-Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Marek Chmelík
- High-Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Ladislav Valkovič
- High-Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
- Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Wolfgang Bogner
- High-Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Rolf Pohmann
- High-Field Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tübingen, Germany
| | - Klaus Scheffler
- Department of Biomedical Magnetic Resonance, University of Tübingen, Tübingen, Germany
- High-Field Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tübingen, Germany
| | - Siegfried Trattnig
- High-Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
- Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna, Austria
| | - Martin Krššák
- High-Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
- Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
18
|
Soares AF, Lei H, Gruetter R. Characterization of hepatic fatty acids in mice with reduced liver fat by ultra-short echo time (1)H-MRS at 14.1 T in vivo. NMR IN BIOMEDICINE 2015; 28:1009-1020. [PMID: 26119835 DOI: 10.1002/nbm.3345] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 05/19/2015] [Accepted: 05/20/2015] [Indexed: 06/04/2023]
Abstract
Alterations in the hepatic lipid content (HLC) and fatty acid composition are associated with disruptions in whole body metabolism, both in humans and in rodent models, and can be non-invasively assessed by (1)H-MRS in vivo. We used (1)H-MRS to characterize the hepatic fatty-acyl chains of healthy mice and to follow changes caused by streptozotocin (STZ) injection. Using STEAM at 14.1 T with an ultra-short TE of 2.8 ms, confounding effects from T2 relaxation and J-coupling were avoided, allowing for accurate estimations of the contribution of unsaturated (UFA), saturated (SFA), mono-unsaturated (MUFA) and poly-unsaturated (PUFA) fatty-acyl chains, number of double bonds, PU bonds and mean chain length. Compared with in vivo (1) H-MRS, high resolution NMR performed in vitro in hepatic lipid extracts reported longer fatty-acyl chains (18 versus 15 carbons) with a lower contribution from UFA (61 ± 1% versus 80 ± 5%) but a higher number of PU bonds per UFA (1.39 ± 0.03 versus 0.58 ± 0.08), driven by the presence of membrane species in the extracts. STZ injection caused a decrease of HLC (from 1.7 ± 0.3% to 0.7 ± 0.1%), an increase in the contribution of SFA (from 21 ± 2% to 45 ± 6%) and a reduction of the mean length (from 15 to 13 carbons) of cytosolic fatty-acyl chains. In addition, SFAs were also likely to have increased in membrane lipids of STZ-induced diabetic mice, along with a decrease of the mean chain length. These studies show the applicability of (1)H-MRS in vivo to monitor changes in the composition of the hepatic fatty-acyl chains in mice even when they exhibit reduced HLC, pointing to the value of this methodology to evaluate lipid-lowering interventions in the scope of metabolic disorders.
Collapse
Affiliation(s)
- Ana Francisca Soares
- Laboratory for Functional and Metabolic Imaging (LIFMET), École Polytechinque Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Hongxia Lei
- Center for Biomedical Imaging (CIBM), Lausanne, Switzerland
- Department of Radiology, University of Geneva (UNIGE), Geneva, Switzerland
| | - Rolf Gruetter
- Laboratory for Functional and Metabolic Imaging (LIFMET), École Polytechinque Fédérale de Lausanne (EPFL), Lausanne, Switzerland
- Department of Radiology, University of Geneva (UNIGE), Geneva, Switzerland
- Department of Radiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| |
Collapse
|
19
|
Begovatz P, Koliaki C, Weber K, Strassburger K, Nowotny B, Nowotny P, Müssig K, Bunke J, Pacini G, Szendrödi J, Roden M. Pancreatic adipose tissue infiltration, parenchymal steatosis and beta cell function in humans. Diabetologia 2015; 58:1646-55. [PMID: 25740696 DOI: 10.1007/s00125-015-3544-5] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 02/04/2015] [Indexed: 12/12/2022]
Abstract
AIMS/HYPOTHESIS This study aimed to perform a comprehensive analysis of interlobular, intralobular and parenchymal pancreatic fat in order to assess their respective effects on beta cell function. METHODS Fifty-six participants (normal glucose tolerance [NGT] (n = 28), impaired fasting glucose (IFG) and/or impaired glucose tolerance (IGT) (n = 14) and patients with type 2 diabetes (n = 14)) underwent a frequent-sampling OGTT and non-invasive magnetic resonance imaging (MRI; whole-body and pancreatic) and proton magnetic resonance spectroscopy ((1)H-MRS; liver and pancreatic fat). Total pancreatic fat was assessed by a standard 2 cm(3) (1)H-MRS method, intralobular fat by 1 cm(3) (1)H-MRS that avoided interlobular fat within modified DIXON (mDIXON) water images, and parenchymal fat by a validated mDIXON-MRI fat-fraction method. RESULTS Comparison of (1)H-MRS techniques revealed an inhomogeneous distribution of interlobular and intralobular adipose tissue, which increased with decreasing glucose tolerance. mDIXON-MRI measurements provided evidence against uniform steatosis, revealing regions of parenchymal tissue void of lipid accumulation in all participants. Total (r = 0.385, p < 0.01) and intralobular pancreas adipose tissue infiltration (r = 0.310, p < 0.05) positively associated with age, but not with fasting or 2 h glucose levels, BMI or visceral fat content (all p > 0.5). Furthermore, no associations were found between total and intralobular pancreatic adipose tissue infiltration and insulin secretion or beta cell function within NGT, IFG/IGT or patients with type 2 diabetes (all p > 0.2). CONCLUSIONS/INTERPRETATION The pancreas does not appear to be another target organ for abnormal endocrine function because of ectopic parenchymal fat storage. No relationship was found between pancreatic adipose tissue infiltration and beta cell function, regardless of glucose tolerance status.
Collapse
Affiliation(s)
- Paul Begovatz
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University, Auf`m Hennekamp 65, 40225, Düsseldorf, Germany
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Gancheva S, Koliaki C, Bierwagen A, Nowotny P, Heni M, Fritsche A, Häring HU, Szendroedi J, Roden M. Effects of intranasal insulin on hepatic fat accumulation and energy metabolism in humans. Diabetes 2015; 64:1966-75. [PMID: 25576060 DOI: 10.2337/db14-0892] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 01/07/2015] [Indexed: 11/13/2022]
Abstract
Studies in rodents suggest that insulin controls hepatic glucose metabolism through brain-liver crosstalk, but human studies using intranasal insulin to mimic central insulin delivery have provided conflicting results. In this randomized controlled crossover trial, we investigated the effects of intranasal insulin on hepatic insulin sensitivity (HIS) and energy metabolism in 10 patients with type 2 diabetes and 10 lean healthy participants (CON). Endogenous glucose production was monitored with [6,6-(2)H2]glucose, hepatocellular lipids (HCLs), ATP, and inorganic phosphate concentrations with (1)H/(31)P magnetic resonance spectroscopy. Intranasal insulin transiently increased serum insulin levels followed by a gradual lowering of blood glucose in CON only. Fasting HIS index was not affected by intranasal insulin in CON and patients. HCLs decreased by 35% in CON only, whereas absolute hepatic ATP concentration increased by 18% after 3 h. A subgroup of CON received intravenous insulin to mimic the changes in serum insulin and blood glucose levels observed after intranasal insulin. This resulted in a 34% increase in HCLs without altering hepatic ATP concentrations. In conclusion, intranasal insulin does not affect HIS but rapidly improves hepatic energy metabolism in healthy humans, which is independent of peripheral insulinemia. These effects are blunted in patients with type 2 diabetes.
Collapse
Affiliation(s)
- Sofiya Gancheva
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research, Heinrich Heine University Düsseldorf, Düsseldorf, Germany German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Düsseldorf, Germany
| | - Chrysi Koliaki
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research, Heinrich Heine University Düsseldorf, Düsseldorf, Germany German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Düsseldorf, Germany
| | - Alessandra Bierwagen
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research, Heinrich Heine University Düsseldorf, Düsseldorf, Germany German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Düsseldorf, Germany
| | - Peter Nowotny
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research, Heinrich Heine University Düsseldorf, Düsseldorf, Germany German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Düsseldorf, Germany
| | - Martin Heni
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Eberhard Karls University, Tübingen, Germany Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen (Paul Langerhans Institute Tübingen), Tübingen, Germany German Center for Diabetes Research (DZD e.V.), Partner Neuherberg, Neuherberg, Germany
| | - Andreas Fritsche
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Eberhard Karls University, Tübingen, Germany Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen (Paul Langerhans Institute Tübingen), Tübingen, Germany German Center for Diabetes Research (DZD e.V.), Partner Neuherberg, Neuherberg, Germany
| | - Hans-Ulrich Häring
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Eberhard Karls University, Tübingen, Germany Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen (Paul Langerhans Institute Tübingen), Tübingen, Germany German Center for Diabetes Research (DZD e.V.), Partner Neuherberg, Neuherberg, Germany
| | - Julia Szendroedi
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research, Heinrich Heine University Düsseldorf, Düsseldorf, Germany German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Düsseldorf, Germany Department of Endocrinology and Diabetology, University Hospital, Düsseldorf, Germany
| | - Michael Roden
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Institute for Diabetes Research, Heinrich Heine University Düsseldorf, Düsseldorf, Germany German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Düsseldorf, Germany Department of Endocrinology and Diabetology, University Hospital, Düsseldorf, Germany
| |
Collapse
|
21
|
Winhofer Y, Krššák M, Wolf P, Anderwald CH, Geroldinger A, Heinze G, Baumgartner-Parzer S, Marculescu R, Stulnig T, Wolzt M, Trattnig S, Luger A, Krebs M. Free fatty acid availability is closely related to myocardial lipid storage and cardiac function in hypoglycemia counterregulation. Am J Physiol Endocrinol Metab 2015; 308:E631-40. [PMID: 25670825 DOI: 10.1152/ajpendo.00371.2014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 02/03/2015] [Indexed: 11/22/2022]
Abstract
Hypoglycemia, a major side effect of intensive glucose-lowering therapy, was recently linked to increased cardiovascular risk in patients with diabetes. Whether increased circulating free fatty acids (FFA) owing to catecholamine-induced lipolysis affect myocardial energy metabolism and thus link hypoglycemia to cardiac vulnerability is unclear. Therefore, this study investigated the impact of hypoglycemia counterregulation (± inhibition of lipolysis) on myocardial lipid content (MYCL) and left ventricular function in healthy subjects. Nine healthy men were studied in randomized order: 1) insulin/hypoglycemia test (IHT; ins+/aci-), 2) IHT during inhibition of adipose tissue lipolysis by acipimox (ins+/aci+), 3) normoglycemia with acipimox (ins-/aci+), and 4) normoglycemia with placebo (ins-/aci-). MYCL and cardiac function were assessed by employing magnetic resonance spectroscopy/imaging at baseline and at 2 and 6 h. In response to acute hypoglycemia, plasma FFA (P<0.0001) and ejection fraction (EF; from 63.2±5.5 to 69.6±6.3%, P=0.0001) increased significantly and were tightly correlated with each other (r=0.68, P=0.0002); this response was completely blunted by inhibition of adipose tissue lipolysis. In the presence of normoglycemia, inhibition of lipolysis was associated with a drop in EF (from 59.2±5.5 to 53.9±6.9%,P=0.005) and a significant decrease in plasma FFA, triglycerides, and MYCL (by 48.5%, P=0.0001). The present data indicate that an intact interorgan cross-talk between adipose tissue and the heart is a prerequisite for catecholamine-mediated myocardial contractility and preservation of myocardial lipid stores in response to acute hypoglycemia.
Collapse
Affiliation(s)
- Yvonne Winhofer
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria;
| | - Martin Krššák
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria; Centre of Excellence, High-Field MR, Department of Radiodiagnostics, Medical University of Vienna, Vienna, Austria
| | - Peter Wolf
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria
| | - Christian-Heinz Anderwald
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria; Mariahilf Community Pharmacy, Arnoldstein, Austria; Medical Direction, Specialized Hospital Complex Agathenhof, Micheldorf, Austria
| | - Angelika Geroldinger
- Center for Medical Statistics, Informatics, and Intelligent Systems, Medical University of Vienna, Vienna, Austria
| | - Georg Heinze
- Center for Medical Statistics, Informatics, and Intelligent Systems, Medical University of Vienna, Vienna, Austria
| | - Sabina Baumgartner-Parzer
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria
| | - Rodrig Marculescu
- Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria
| | - Thomas Stulnig
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria; Christian Doppler Laboratory for Cardio-Metabolic Immunotherapy, Department of Medicine III, Medical University of Vienna, Vienna, Austria; and
| | - Michael Wolzt
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria; Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Siegfried Trattnig
- Centre of Excellence, High-Field MR, Department of Radiodiagnostics, Medical University of Vienna, Vienna, Austria
| | - Anton Luger
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria
| | - Michael Krebs
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
22
|
Winhofer Y, Wolf P, Krššák M, Wolfsberger S, Tura A, Pacini G, Gessl A, Raber W, Kukurova IJ, Kautzky-Willer A, Knosp E, Trattnig S, Krebs M, Luger A. No evidence of ectopic lipid accumulation in the pathophysiology of the acromegalic cardiomyopathy. J Clin Endocrinol Metab 2014; 99:4299-306. [PMID: 25148232 DOI: 10.1210/jc.2014-2242] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT PATIENTS with acromegaly frequently display disturbances of glucose and lipid metabolism, which might contribute to their increased cardiovascular risk. Because insulin resistance and increased lipolysis have been linked to ectopic lipid deposition, altered lipid accumulation in the liver and the myocardium might contribute to metabolic and cardiac complications in these patients. OBJECTIVE The aim of this study was to investigate myocardial (MYCL) and hepatic lipid content (HCL), insulin sensitivity, and cardiac function in active acromegaly and after control of GH excess through transsphenoidal surgery. PATIENTS Ten patients with newly diagnosed acromegaly (ACRO_active) were compared with 12 healthy controls (CON), matched for age, body mass index, and gender. In seven patients GH excess was controlled, and they were compared with their active state. METHODS MYCL and HCL were assessed by (1)H-magnetic resonance spectroscopy, pericardial fat and cardiac function by (1)H-magnetic resonance imaging, and insulin sensitivity and secretion by an oral glucose tolerance test. RESULTS Although MYCL tended to be lower, HCL was significantly lower in ACRO_active compared with CON (HCL: 1.2% ± 1.2% vs 4.3% ± 3.5% of (1)H-magnetic resonance spectroscopy signal, P < .02). Parameters of systolic function and hypertrophy were significantly increased in ACRO_active compared with CON, as were insulin secretion and resistance. After the control of GH excess, HCL and MYCL remained unchanged, but pericardial fat was increased in the patients in whom GH excess was controlled (from 11.6 ± 5.5 to 14.7 ± 6.2 cm(2), P = .02). CONCLUSION Acromegaly represents a unique condition characterized by low myocardial and hepatic lipid content despite decreased insulin sensitivity, hyperinsulinemia, and hyperglycemia. Hence, ectopic lipid accumulation does not appear to contribute to cardiac morbidity, and increased lipid oxidation might counteract ectopic lipid accumulation in GH excess.
Collapse
Affiliation(s)
- Yvonne Winhofer
- Department of Internal Medicine III, Division of Endocrinology and Metabolism (Y.W., P.W., M.Krš., A.G., W.R., A.K.-W., M.Kre., A.L.), Department of Biomedical Imaging and Image Guided therapy, Centre of Excellence High-field MR (M.Krš., I.J.K., S.T.), and Department of Neurosurgery (S.W., E.K.), Medical University of Vienna, A-1090 Vienna, Austria; and Institute of Biomedical Engineering (A.T., G.P.), National Research Council, Metabolic Unit, I-35127 Padova, Italy
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Runge JH, Bakker P, Gaemers I, Verheij J, Hakvoort TB, Ottenhoff R, Stoker J, Nederveen AJ. Quantitative determination of liver triglyceride levels with 3T ¹H-MR spectroscopy in mice with moderately elevated liver fat content. Acad Radiol 2014; 21:1446-54. [PMID: 25300722 DOI: 10.1016/j.acra.2014.06.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 06/23/2014] [Accepted: 06/23/2014] [Indexed: 01/01/2023]
Abstract
RATIONALE AND OBJECTIVES To diagnose hepatic steatosis with noninvasive magnetic resonance (MR)-based measurements, threshold values of liver fat percentages are used. However, these differ between studies. Consequently, the choice of threshold values influences diagnostic accuracy, especially in subjects with borderline hepatic steatosis. In this study, we compared (1)H-MR spectroscopy (MRS) and biochemically determined liver fat content in mice with moderately elevated fat content and studied the diagnostic accuracy of (1)H-MRS using two literature-based threshold values. MATERIALS AND METHODS Fifty mice were divided into three groups: 21 C57Bl/6OlaHSD (B6) mice on a high-fat diet, 20 B6 mice on a control diet, and 9 LDLr-/- mice on a high-fat high-cholesterol diet. (1)H-MRS was performed using multi-echo STEAM at 3T to derive a fat mass fraction ((1)H-MRS fat content). Biochemical fat content was determined from liver homogenates. Correlation and agreement were assessed with the Pearson correlation coefficient and the Bland-Altman analysis and diagnostic accuracy by calculating sensitivity, specificity, and positive and negative predictive values. RESULTS All mice were pooled to form a single cohort. Mean (±standard deviation) biochemical fat content was 32.2 (±13.9) mg/g. Mean (1)H-MRS fat content did not differ at 30.2 (±12.0) mg/g (P = .13). Correlation r was 0.74 (P < .0001). Bland-Altman analysis indicated that (1)H-MRS fat content underestimated biochemical fat content by 2.1 mg/g. The diagnostic accuracy of (1)H-MRS depended to a great extent on the chosen reference threshold value. CONCLUSIONS (1)H-MRS measurement of moderately elevated liver fat content in mice correlated substantially with biochemical fat content measurement. Contrary to earlier studies, diagnostic accuracy of (1)H-MRS fat content in borderline liver fat content appears limited.
Collapse
|
24
|
Wolf P, Winhofer Y, Anderwald CH, Krššák M, Krebs M. Intracellular lipid accumulation and shift during diabetes progression. Wien Med Wochenschr 2014; 164:320-9. [DOI: 10.1007/s10354-014-0292-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Accepted: 06/23/2014] [Indexed: 02/08/2023]
|
25
|
Firneisz G. Non-alcoholic fatty liver disease and type 2 diabetes mellitus: The liver disease of our age? World J Gastroenterol 2014; 20:9072-9089. [PMID: 25083080 PMCID: PMC4112878 DOI: 10.3748/wjg.v20.i27.9072] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 01/10/2014] [Accepted: 05/14/2014] [Indexed: 02/07/2023] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a chronic liver disease that might affect up to one-third of the adult population in industrialised countries. NAFLD incorporates histologically and clinically different non-alcoholic entities; fatty liver (NAFL, steatosis hepatis) and steatohepatitis (NASH-characterised by hepatocyte ballooning and lobular inflammation ± fibrosis) might progress to cirrhosis and rarely to hepatocellular cancer. NAFL increasingly affects children (paediatric prevalence is 4.2%-9.6%). Type 2 diabetes mellitus (T2DM), insulin resistance (IR), obesity, metabolic syndrome and NAFLD are particularly closely related. Increased hepatic lipid storage is an early abnormality in insulin resistant women with a history of gestational diabetes mellitus. The accumulation of triacylglycerols in hepatocytes is predominantly derived from the plasma nonesterified fatty acid pool supplied largely by the adipose tissue. A few NAFLD susceptibility gene variants are associated with progressive liver disease, IR, T2DM and a higher risk for hepatocellular carcinoma. Although not approved, pharmacological approaches might be considered in NASH patients.
Collapse
|
26
|
Krššák M. Novel labeling approaches for the assessment of human hepatic metabolism by in vivo magnetic resonance spectroscopy. Hepatology 2014; 59:2077-9. [PMID: 24700320 DOI: 10.1002/hep.27091] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Accepted: 02/19/2014] [Indexed: 12/07/2022]
Affiliation(s)
- Martin Krššák
- From the Division of Endocrinology and Metabolism, Department of Internal Medicine III, and High Field MR Centre, Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
27
|
Kahl S, Straßburger K, Nowotny B, Livingstone R, Klüppelholz B, Keßel K, Hwang JH, Giani G, Hoffmann B, Pacini G, Gastaldelli A, Roden M. Comparison of liver fat indices for the diagnosis of hepatic steatosis and insulin resistance. PLoS One 2014; 9:e94059. [PMID: 24732091 PMCID: PMC3986069 DOI: 10.1371/journal.pone.0094059] [Citation(s) in RCA: 109] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 03/11/2014] [Indexed: 12/20/2022] Open
Abstract
Context Hepatic steatosis, defined as increased hepatocellular lipid content (HCL), associates with visceral obesity and glucose intolerance. As exact HCL quantification by 1H-magnetic resonance spectroscopy (1H-MRS) is not generally available, various clinical indices are increasingly used to predict steatosis. Objective The purpose of this study was to test the accuracy of NAFLD liver fat score (NAFLD-LFS), hepatic steatosis index (HSI) and fatty liver index (FLI) against 1H-MRS and their relationships with insulin sensitivity and secretion. Design, Setting and Participants Ninety-two non-diabetic, predominantly non-obese humans underwent clinical examination, 1H-MRS and an oral glucose tolerance test (OGTT) to calculate insulin sensitivity and β-cell function. Accuracy of indices was assessed from the area under the receiver operating characteristic curve (AROC). Results Median HCL was 2.49% (0.62;4.23) and correlated with parameters of glycemia across all subjects. NAFLD-LFS, FLI and HSI yielded AROCs of 0.70, 0.72, and 0.79, respectively, and related positively to HCL, insulin resistance, fasting and post-load β-cell function normalized for insulin resistance. Upon adjustment for age, sex and HCL, regression analysis revealed that NAFLD-LFS, FLI and HSI still independently associated with both insulin sensitivity and β-cell function. Conclusion The tested indices offer modest efficacy to detect steatosis and cannot substitute for fat quantification by 1H-MRS. However, all indices might serve as surrogate parameters for liver fat content and also as rough clinical estimates of abnormal insulin sensitivity and secretion. Further validation in larger collectives such as epidemiological studies is needed.
Collapse
Affiliation(s)
- Sabine Kahl
- Institute for Clinical Diabetology, German Diabetes Center at Heinrich-Heine University, Düsseldorf, Germany
- Department of Endocrinology and Diabetology, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Klaus Straßburger
- Institute for Clinical Diabetology, German Diabetes Center at Heinrich-Heine University, Düsseldorf, Germany
| | - Bettina Nowotny
- Institute for Clinical Diabetology, German Diabetes Center at Heinrich-Heine University, Düsseldorf, Germany
- Department of Endocrinology and Diabetology, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Roshan Livingstone
- Institute for Clinical Diabetology, German Diabetes Center at Heinrich-Heine University, Düsseldorf, Germany
| | - Birgit Klüppelholz
- Institute for Biometrics and Epidemiology, German Diabetes Center at Heinrich-Heine University, Düsseldorf, Germany
| | - Kathrin Keßel
- Institute for Clinical Diabetology, German Diabetes Center at Heinrich-Heine University, Düsseldorf, Germany
| | - Jong-Hee Hwang
- Institute for Clinical Diabetology, German Diabetes Center at Heinrich-Heine University, Düsseldorf, Germany
| | - Guido Giani
- Institute for Biometrics and Epidemiology, German Diabetes Center at Heinrich-Heine University, Düsseldorf, Germany
| | - Barbara Hoffmann
- IUF – Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany
| | - Giovanni Pacini
- National Research Council, Institute of Biomedical Engineering, Metabolic Unit, Padova, Italy
| | - Amalia Gastaldelli
- National Research Council, Institute of Clinical Physiology, Pisa, Italy
| | - Michael Roden
- Institute for Clinical Diabetology, German Diabetes Center at Heinrich-Heine University, Düsseldorf, Germany
- Department of Endocrinology and Diabetology, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
- German Center for Diabetes Research, Partner Düsseldorf, Germany
- * E-mail:
| |
Collapse
|
28
|
Valkovič L, Gajdošík M, Traussnigg S, Wolf P, Chmelík M, Kienbacher C, Bogner W, Krebs M, Trauner M, Trattnig S, Krššák M. Application of localized ³¹P MRS saturation transfer at 7 T for measurement of ATP metabolism in the liver: reproducibility and initial clinical application in patients with non-alcoholic fatty liver disease. Eur Radiol 2014; 24:1602-9. [PMID: 24647824 DOI: 10.1007/s00330-014-3141-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Revised: 02/10/2014] [Accepted: 02/27/2014] [Indexed: 12/27/2022]
Abstract
OBJECTIVES Saturation transfer (ST) phosphorus MR spectroscopy ((31)P MRS) enables in vivo insight into energy metabolism and thus could identify liver conditions currently diagnosed only by biopsy. This study assesses the reproducibility of the localized (31)P MRS ST in liver at 7 T and tests its potential for noninvasive differentiation of non-alcoholic fatty liver (NAFL) and steatohepatitis (NASH). METHODS After the ethics committee approval, reproducibility of the localized (31)P MRS ST at 7 T and the biological variation of acquired hepato-metabolic parameters were assessed in healthy volunteers. Subsequently, 16 suspected NAFL/NASH patients underwent MRS measurements and diagnostic liver biopsy. The Pi-to-ATP exchange parameters were compared between the groups by a Mann-Whitney U test and related to the liver fat content estimated by a single-voxel proton ((1)H) MRS, measured at 3 T. RESULTS The mean exchange rate constant (k) in healthy volunteers was 0.31 ± 0.03 s(-1) with a coefficient of variation of 9.0 %. Significantly lower exchange rates (p < 0.01) were found in NASH patients (k = 0.17 ± 0.04 s(-1)) when compared to healthy volunteers, and NAFL patients (k = 0.30 ± 0.05 s(-1)). Significant correlation was found between the k value and the liver fat content (r = 0.824, p < 0.01). CONCLUSIONS Our data suggest that the (31)P MRS ST technique provides a tool for gaining insight into hepatic ATP metabolism and could contribute to the differentiation of NAFL and NASH. KEY POINTS • 1D localized (31) P MRS saturation transfer in the liver is reproducible at 7 T • NASH patients have decreased hepatic Pi-to-ATP exchange rate • In this study, hepatic metabolic activity correlates with liver fat content.
Collapse
Affiliation(s)
- Ladislav Valkovič
- High Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Winhofer Y, Krššák M, Wolf P, Tura A, Anderwald CH, Kosi L, Reiter G, Pacini G, Trattnig S, Luger A, Krebs M, Kautzky-Willer A. Hepatic rather than cardiac steatosis relates to glucose intolerance in women with prior gestational diabetes. PLoS One 2014; 9:e91607. [PMID: 24621572 PMCID: PMC3951459 DOI: 10.1371/journal.pone.0091607] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 02/13/2014] [Indexed: 11/19/2022] Open
Abstract
Background Increased myocardial lipid accumulation has been described in patients with pre- and overt type 2 diabetes and could underlie the development of left-ventricular dysfunction in metabolic diseases (diabetic cardiomyopathy). Since women with prior gestational diabetes (pGDM) display a generally young population at high risk of developing diabetes and associated cardiovascular complications, we aimed to assess whether myocardial lipid accumulation can be detected at early stages of glucose intolerance and relates to markers of hepatic steatosis (Fatty Liver Index), cardiac function, insulin sensitivity and secretion. Methods Myocardial lipid content (MYCL), left-ventricular function (1H-magnetic-resonance-spectroscopy and -imaging), insulin sensitivity/secretion (oral glucose tolerance test) and the fatty liver index (FLI) were assessed in 35 pGDM (45.6±7.0 years, 28.3±4.8 kg/m2) and 14 healthy control females (CON; 44.7±9.8 years, 26.1±2.5 kg/m2), matching for age and body-mass-index (each p>0.1). Results Of 35 pGDM, 9 displayed normal glucose tolerance (NGT), 6 impaired glucose regulation (IGR) and 20 had been already diagnosed with type 2 diabetes (T2DM). MYCL and cardiac function were comparable between pGDM and CON; in addition, no evidence of left-ventricular dysfunction was observed. MYCL was inversely correlated with the ejection fraction in T2DM (R = −0.45, p<0.05), while the FLI was tightly correlated with metabolic parameters (such as HbA1C, fasting plasma glucose and HDL-cholesterol) and rose along GT-groups. Conclusions There is no evidence of cardiac steatosis in middle-aged women with prior gestational diabetes, suggesting that cardiac complications might develop later in the time-course of diabetes and may be accelerated by the co-existence of further risk factors, whereas hepatic steatosis remains a valid biomarker for metabolic diseases even in this rather young female cohort.
Collapse
Affiliation(s)
- Yvonne Winhofer
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria
- * E-mail:
| | - Martin Krššák
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria
| | - Peter Wolf
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria
| | - Andrea Tura
- Metabolic Unit, Institute of Biomedical Engineering, National Research Council, Padova, Italy
| | - Christian-Heinz Anderwald
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria
- Metabolic Unit, Institute of Biomedical Engineering, National Research Council, Padova, Italy
- Mariahilf Community Pharmacy, Arnoldstein, Austria
- Medical Direction, Specialized Hospital Complex Agathenhof, Micheldorf, Austria
| | - Lana Kosi
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria
| | | | - Giovanni Pacini
- Metabolic Unit, Institute of Biomedical Engineering, National Research Council, Padova, Italy
| | - Siegfried Trattnig
- Centre of Excellence, High-Field MR, Department of Radiodiagnostics, Medical University of Vienna, Vienna, Austria
| | - Anton Luger
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria
| | - Michael Krebs
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria
| | - Alexandra Kautzky-Willer
- Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
30
|
Hock A, Valkovič L, Geier A, Kuntzen T, Boesiger P, Henning A. Navigator based respiratory gating during acquisition and preparation phases for proton liver spectroscopy at 3 T. NMR IN BIOMEDICINE 2014; 27:348-355. [PMID: 24591124 DOI: 10.1002/nbm.3069] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 12/02/2013] [Accepted: 12/03/2013] [Indexed: 06/03/2023]
Abstract
Proton magnetic resonance spectroscopy ((1)H MRS) enables the non-invasive investigation of the human liver; however, because of technical difficulties it is not regularly used for diagnosis of liver diseases in clinical routine. Breathing motion is one of the major challenges, as it decreases spectral quality and leads to misplacement of the spectroscopic voxel. To overcome this problem, real-time navigator gating for spectral acquisition and preparation steps (B0 shimming, water frequency determination, receiver gain optimization, and water suppression) combined with short TE , optimized first order projection based B0 shimming, water suppression, and inner-volume saturated point resolved spectroscopy (PRESS) at 3 T is suggested. Simultaneous lipid and trimethylamine quantification is demonstrated by means of phantom, volunteer, and representative patient measurements. Precise localization of the voxel despite respiratory motion, increased spectral quality (higher signal-to-noise ratio and reduced linewidth) compared with measurements without respiratory gating, and the possibility of acquiring data without additional subject instructions regarding breathing enable robust and accurate liver (1)H MRS measurements with this novel acquisition protocol.
Collapse
Affiliation(s)
- A Hock
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland; Department of Psychiatry, Psychotherapy and Psychosomatics, Zurich University Hospital for Psychiatry, Zurich, Switzerland
| | | | | | | | | | | |
Collapse
|
31
|
Livingstone RS, Begovatz P, Kahl S, Nowotny B, Strassburger K, Giani G, Bunke J, Roden M, Hwang JH. Initial clinical application of modified Dixon with flexible echo times: hepatic and pancreatic fat assessments in comparison with (1)H MRS. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2013; 27:397-405. [PMID: 24306514 DOI: 10.1007/s10334-013-0421-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2013] [Revised: 10/30/2013] [Accepted: 11/06/2013] [Indexed: 12/11/2022]
Abstract
OBJECTS Hepatic and pancreatic fat content become increasingly important for phenotyping of individuals with metabolic diseases. This study aimed to (1) evaluate hepatic fat fractions (HFF) and pancreatic fat fractions (PFF) using (1)H magnetic resonance spectroscopy (MRS) and the recently introduced fast mDixon method, and to examine body fat effects on HFF and PFF, (2) investigate regional differences in HFF and PFF by mDixon. MATERIALS AND METHODS HFF and PFF were quantified by mDixon with two flexible echo times and by single voxel (1)H MRS in 24 healthy subjects. The regional differences of PFF within the pancreas were assessed with mDixon. Abdominal visceral and subcutaneous fat was assessed by T1-weighted MRI at 3T. RESULTS Both methods correlated well for quantification of HFF (r = 0.98, p < 0.0001) and PFF (r = 0.80, p < 0.0001). However, mDixon showed a higher low limit in HFF and PFF. PFF showed no regional differences using mDixon. In addition, both visceral and subcutaneous fat correlated with pancreatic fat, while only visceral fat correlated with liver fat, employing both (1)H MRS and mDixon. CONCLUSION The novel and fast two-point mDixon exhibits a good correlation with the gold-standard (1)H MRS for assessment of HFF and PFF, with limited sensitivity for assessing lower fat content.
Collapse
Affiliation(s)
- Roshan S Livingstone
- Metabolic Imaging Group, Institute of Clinical Diabetology, German Diabetes Center at Heinrich-Heine University, Auf dem Hennekamp 65, 40225, Düsseldorf, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Gajdošík M, Chmelík M, Just-Kukurová I, Bogner W, Valkovič L, Trattnig S, Krššák M. In vivo relaxation behavior of liver compounds at 7 Tesla, measured by single-voxel proton MR spectroscopy. J Magn Reson Imaging 2013; 40:1365-74. [PMID: 24222653 DOI: 10.1002/jmri.24489] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Accepted: 10/01/2013] [Indexed: 12/19/2022] Open
Abstract
PURPOSE To assess the proton T1 and T2 relaxation of in vivo hepatic water, choline and lipid resonances with possible J-coupling behavior of lipids in healthy volunteers at 7 Tesla (T). MATERIALS AND METHODS Relaxation measurements were conducted on corn oil phantoms and on the hepatic tissue of 11 healthy volunteers at 7 T using a surface coil and a STEAM sequence. T1 's were determined by monoexponential fitting, and T2 's by both monoexponential and enhanced-exponential fitting (empirically designed to consider J-coupling of lipid resonances). RESULTS In vivo T1 's at 7 T were estimated as follows: water (4.70 ppm), 1362 ± 83 ms; methyl- (0.90 ppm), 1026 ± 162 ms; methylene- (1.30 ppm), 514 ± 25 ms; α-olefinic- (2.02 ppm), 488 ± 220 ms; α-carboxyl- (2.24 ppm), 476 ± 89 ms; diacyl- (2.77 ppm), 479 ± 260 ms group of lipid chains; and choline compounds (3.22 ppm), 1084 ± 52 ms. The T2 's calculated with enhanced fitting were as follows: water, 15 ± 2 ms; methyl-, 34 ± 10 ms; methylene-, 41 ± 8 ms; α-olefinic-, 44 ± 19 ms; α-carboxyl-, 39 ± 15 ms; diacyl-, 44 ± 5 ms group of lipid chains; and choline compounds, 32 ± 9 ms. CONCLUSION An accurate knowledge of in vivo relaxation and J-coupling behavior will significantly improve the quantification of an extended number of resolved liver metabolites at 7 T.
Collapse
Affiliation(s)
- Martin Gajdošík
- MR Center of Excellence Department of Biomedical Imaging and Image-guided Therapy, Medical University Vienna, Vienna, Austria
| | | | | | | | | | | | | |
Collapse
|
33
|
Phielix E, Brehm A, Bernroider E, Krssak M, Anderwald CH, Krebs M, Schmid AI, Nowotny P, Roden M. Effects of pioglitazone versus glimepiride exposure on hepatocellular fat content in type 2 diabetes. Diabetes Obes Metab 2013; 15:915-22. [PMID: 23574533 DOI: 10.1111/dom.12112] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Revised: 01/14/2013] [Accepted: 02/22/2013] [Indexed: 12/31/2022]
Abstract
AIMS Thiazoledinediones decrease blood glucose by their insulin-sensitizing properties. Here, we examined whether pioglitazone plus nateglinide (PIO) interferes with hepatocellular lipid (HCL) content and/or improves insulin sensitivity in well-controlled non-obese patients with type 2 diabetes mellitus (T2DM). METHODS Sixteen patients [body mass index (BMI): 28 ± 1 kg/m(2) ; HbA1c: 7.1 ± 0.6%] were studied in a randomized, double-blind, 12-week parallel group trial, whereas matched healthy humans [non-diabetic control subjects (CON), BMI: 26 ± 1 kg/m(2)] were studied once. Treatment with pioglitazone (30 mg/day) plus nateglinide (PIO arm) to control for glimepiride-induced insulin secretion was compared to treatment with glimepiride (2 mg/day) plus placebo (GLI arm). Multinuclei magnetic resonance spectroscopy (MRS) was combined with pancreatic normoglycaemic-two-step-insulin clamps and stable isotopes to assess glucose turnover, glucose transport/phosphorylation, HCL and intramyocellular lipid (IMCL) contents, non-esterified fatty acids (NEFA) and adipokines. RESULTS At baseline, HCL was approximately 5.6-fold higher in T2DM (p < 0.05 vs. CON). This was paralleled by approximately doubled leptin : adiponectin ratios (p < 0.05). HCL decreased by approximately 39% (p < 0.05) after PIO and only tended to decrease after GLI (p = 0.12). Treatment with PIO did not affect leptin : adiponectin ratios, but slightly improved (p < 0.05) insulin-mediated NEFA suppression, which related to lower HCL. PIO further prevented the insulin-induced increase in IMCL content of soleus and tibialis anterior muscles. Peripheral and hepatic insulin sensitivity, glucose transport and glycaemic control did not change in both groups. CONCLUSION Short-term, low-dose thiazolidendione treatment improves insulin sensitivity of lipolysis and HCL, without affecting muscle and liver insulin sensitivity. It appears that metabolic PIO action in T2DM is primarily mediated via a decline in HCL associated with greater sensitivity of lipolysis to insulin.
Collapse
Affiliation(s)
- E Phielix
- Institute for Clinical Diabetology, German Diabetes Center, Düsseldorf, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Effects of insulin therapy on myocardial lipid content and cardiac geometry in patients with type-2 diabetes mellitus. PLoS One 2012; 7:e50077. [PMID: 23226508 PMCID: PMC3513303 DOI: 10.1371/journal.pone.0050077] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Accepted: 10/15/2012] [Indexed: 01/01/2023] Open
Abstract
Aims/Hypothesis Recent evidence suggests a link between myocardial steatosis and diabetic cardiomyopathy. Insulin, as a lipogenic and growth-promoting hormone, might stimulate intramyocardial lipid (MYCL) deposition and hypertrophy. Therefore, the aim of the present study was to investigate the short-term effects of insulin therapy (IT) on myocardial lipid content and morphology in patients with T2DM. Methods Eighteen patients with T2DM were recruited (age 56±2 years; HbA1c: 10.5±0.4%). In 10 patients with insufficient glucose control under oral medication IT was initiated due to secondary failure of oral glucose lowering therapy (IT-group), while 8 individuals did not require additional insulin substitution (OT-group). In order to assess MYCL and intrahepatic lipid (IHLC) content as well as cardiac geometry and function magnetic resonance spectroscopy (MRS) and imaging (MRI) examinations were performed at baseline (IT and OT) and 10 days after initiation of IT. Follow up measurements took place 181±49 days after IT. Results Interestingly, basal MYCLs were 50% lower in IT- compared to OT-group (0.41±0.12 vs. 0.80±0.11% of water signal; p = 0.034). After 10 days of IT, an acute 80%-rise in MYCL (p = 0.008) was observed, while IHLC did not change. Likewise, myocardial mass (+13%; p = 0.004), wall thickness in end-diastole (+13%; p = 0.030) and concentricity, an index of cardiac remodeling, increased (+28%; p = 0.026). In the long-term MYCL returned to baseline, while IHCL significantly decreased (−31%; p = 0.000). No acute changes in systolic left ventricular function were observed. Conclusions/Interpretation The initiation of IT in patients with T2DM was followed by an acute rise in MYCL concentration and myocardial mass.
Collapse
|
35
|
Ouwerkerk R, Pettigrew RI, Gharib AM. Liver metabolite concentrations measured with 1H MR spectroscopy. Radiology 2012; 265:565-75. [PMID: 22891360 DOI: 10.1148/radiol.12112344] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
PURPOSE To determine the feasibility of measuring choline and glycogen concentrations in normal human liver in vivo with proton (hydrogen 1 [1H]) magnetic resonance (MR) spectroscopy. MATERIALS AND METHODS Signed consent to participate in an institutional review board-approved and HIPAA-compliant study was obtained from 46 subjects (mean age, 46 years±17 [standard deviation]; 24 women) consecutively recruited during 285 days. Navigator-gated MR images were used to select 8-mL volumes for point-resolved spectroscopy (PRESS) with a 35-msec echo time. Line widths were minimized with fast breath-hold B0 field mapping and further manual shimming. Navigator-gated spectra were recorded with and without water suppression to determine metabolite concentrations with water signals as an internal reference. In three subjects, echo time was varied to determine the glycogen and choline T2. Linear regression analysis was used to examine relations between choline, hepatic lipid content, body mass index, glycogen content, and age. RESULTS Choline concentrations could be determined in 46 of 48 studies and was found to be 8.6 mmol per kilogram of wet weight±3.1 (range, 3.8-17.6; n=44). Twenty-seven spectra in 25 individuals with narrow line widths and low lipid content were adequate for quantitation of glycogen. The glycogen (glucosyl unit) concentration was 38.1 mmol/kg wet weight±14.4. The T2 of combined glycogen peaks in the liver of three subjects was 36 msec±8. Choline levels showed a weak but significant correlation with glycogen (r2=0.15; P<.05) but not with lipid content. CONCLUSION Navigator-gated and gradient-echo shimmed PRESS 1H MR spectroscopy may allow quantification of liver metabolites that are important for understanding and identifying disorders of glucose and lipid metabolism.
Collapse
Affiliation(s)
- Ronald Ouwerkerk
- Biomedical and Metabolic Imaging Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 10 Center Dr, CRC Building 10, Room 3-5340, MSC 1263, Bethesda, MD 20892-1263, USA.
| | | | | |
Collapse
|
36
|
Koelblinger C, Krššák M, Maresch J, Wrba F, Kaczirek K, Gruenberger T, Tamandl D, Ba-Ssalamah A, Berger-Kulemann V, Weber M, Schima W. Hepatic steatosis assessment with 1H-spectroscopy and chemical shift imaging at 3.0 T before hepatic surgery: reliable enough for making clinical decisions? Eur J Radiol 2012; 81:2990-5. [PMID: 22770582 DOI: 10.1016/j.ejrad.2012.01.025] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Revised: 01/09/2012] [Accepted: 01/11/2012] [Indexed: 12/20/2022]
Abstract
PURPOSE To compare the accuracy of liver fat quantification using chemical shift imaging (CSI) and H1 MR-spectroscopy (MRS) at 3.0 T in patients undergoing liver resection. METHODS Totally 35 patients were included in this prospective IRB approved study. The histopathologically assessed liver fat was compared to the hepatic fat fractions calculated with CSI (with and without spleen correction) and MRS. Spearman's rank correlation and Fisher z-test were used for correlation analysis. Sensitivity and specificity regarding the detection of marked steatosis were calculated for the different modalities and compared using the McNemar test. RESULTS MRS (r=.85) and CSI with spleen correction (r=.85) showed a significantly better correlation (p=.03) with histology compared to CSI without spleen correction (r=.67). Sensitivity and specificity for the detection of marked steatosis was 100% (12/12) and 87% (20/23) for MRS and 92% (11/12) and 83% (19/23) for CSI with spleen correction (p>.12). CONCLUSION For the assessment of hepatic steatosis both CSI with spleen correction and MRS at 3.0 T, show a good correlation with histology. CSI without spleen correction should not be used. Sensitivity and specificity for the detection of marked steatosis are high with both modalities. However, results that are scattered around the cut-off values are not reliable enough for clinical decisions.
Collapse
Affiliation(s)
- Claus Koelblinger
- Department of Radiology, Medical University of Vienna, Vienna, Austria.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Georgoff P, Thomasson D, Louie A, Fleischman E, Dutcher L, Mani H, Kottilil S, Morse C, Dodd L, Kleiner D, Hadigan C. Hydrogen-1 MR spectroscopy for measurement and diagnosis of hepatic steatosis. AJR Am J Roentgenol 2012; 199:2-7. [PMID: 22733887 PMCID: PMC3422734 DOI: 10.2214/ajr.11.7384] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE Hydrogen-1 MR spectroscopy ((1)H-MRS) is gaining acceptance as a noninvasive technique for assessment of hepatic steatosis, and the findings have been found to correlate closely with histopathologic grade. The aims of this study were to validate (1)H-MRS performed with a 3-T MRI system for quantifying hepatic steatosis and to determine threshold values of (1)H-MRS proton density fat fraction corresponding to standard histopathologic grade in patients undergoing diagnostic liver biopsy. SUBJECTS AND METHODS We conducted a prospective cross-sectional liver MRS study with 52 subjects undergoing diagnostic liver biopsy. The diagnostic accuracy of (1)H-MRS was evaluated with receiver operating characteristic curves. RESULTS The diagnostic accuracy of (1)H-MRS for hepatic steatosis was high with an area under the receiver operating characteristic curve of 0.94 (95% CI, 0.88-1.0). Results were similar for three (1)H-MRS measurements obtained at different locations in the liver, for two independent pathologists, and whether fibrosis was present or absent. One third of participants had elevated transaminase concentrations of unknown cause, and (1)H-MRS estimates of steatosis had perfect agreement with histopathologic grade in this group. Calculated (1)H-MRS proton density fat fraction thresholds for histologic grades were less than 17% for grade 0 or trace steatosis, 17-38.6% for grade 1, and greater than 38.6% for grade 2 or higher. CONCLUSION Hydrogen-1 MR spectroscopy is an effective, noninvasive technique that can be used to diagnose and quantify hepatic steatosis. Hydrogen-1 MR spectroscopy thresholds corresponded with histopathologic grades and may be useful in the workup of patients with elevated transaminase concentrations.
Collapse
Affiliation(s)
- Patrick Georgoff
- University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Gambarota G, Tanner M, van der Graaf M, Mulkern RV, Newbould RD. 1H-MRS of hepatic fat using short TR at 3T: SNR optimization and fast T2 relaxometry. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2011; 24:339-45. [PMID: 21892734 DOI: 10.1007/s10334-011-0278-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2011] [Revised: 08/11/2011] [Accepted: 08/11/2011] [Indexed: 01/02/2023]
Abstract
OBJECT To increase the signal-to-noise ratio (SNR) efficiency of hepatic fat signals in proton magnetic resonance spectroscopy (1H MRS) at 3 T, in order to improve the quantitation of hepatic fat and allow fast, single breath-hold T2 relaxometry of hepatic water and fat. MATERIALS AND METHODS Since the T1 of lipid protons is relatively short, we hypothesized that it could be possible to increase the lipid SNR efficiency by choosing a TR shorter than that typically employed (≥1.5 s). The lipid SNR per unit-time was calculated using published values of lipid (CH2)n protons' T1 at 3 T. 1H MRS PRESS spectra were acquired from VOIs located in the right lobe of the liver in 28 healthy volunteers. At the short TR of 0.6 s, fast T2 relaxometry with the acquisition of 16 echo times (30, 40, ..., 180 ms), was performed in a single breath-hold measurement using a modified PRESS sequence. RESULTS Good agreement was observed between simulated and experimental data, with the shortening of TR to 0.6 s yielding an ~50% SNR improvement of hepatic lipid (CH2)n resonances, compared to the SNR at TR=2 s. The T2 relaxation time of water and lipid (CH2)n protons at 3 T was 25.8±1.1 ms and 55.4±3.9 ms, respectively, across five healthy volunteers. CONCLUSION The short-TR approach allows for an improved SNR efficiency of lipids and for fast T2 relaxometry of hepatic water and fat, with a detailed coverage of the T2 relaxation decay curve, within a single breath-hold experiment.
Collapse
Affiliation(s)
- Giulio Gambarota
- GlaxoSmithKline Clinical Imaging Centre, Imperial College, Hammersmith Hospital, Du Cane Road, London, W12 0NN, UK.
| | | | | | | | | |
Collapse
|
39
|
The role of metformin and thiazolidinediones in the regulation of hepatic glucose metabolism and its clinical impact. Trends Pharmacol Sci 2011; 32:607-16. [PMID: 21824668 DOI: 10.1016/j.tips.2011.06.006] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Revised: 06/16/2011] [Accepted: 06/21/2011] [Indexed: 12/25/2022]
Abstract
Fasting hyperglycemia in type 2 diabetes mellitus (T2DM) results from elevated endogenous glucose production (EGP), which is mostly due to augmented hepatic gluconeogenesis. Insulin-resistant humans exhibit impaired insulin-dependent suppression of EGP and excessive hepatic lipid storage (steatosis), which relates to abnormal supply of free fatty acids (FFA) and energy metabolism. Only two glucose-lowering drug classes, the biguanide metformin and the thiazolidendiones (TZDs), exert insulin- and glucagon-independent hepatic effects. Preclinical studies suggest that metformin inhibits mitochondrial complex I. TZDs, as peroxisome proliferator-activated receptor (PPAR) γ-agonists, predominantly reduce the flux of FFA and cytokines from adipose tissue to the liver, but could also directly inhibit mitochondrial complex I. Although both metformin and TZDs improve fasting hyperglycemia and EGP in clinical trials, only TZDs decrease steatosis and peripheral insulin resistance. More studies are required to address their effects on hepatocellular energy metabolism with a view to identifying novel targets for the treatment of T2DM.
Collapse
|
40
|
MR spectroscopy as a tool for in vivo determination of steatosis in liver transplant recipients. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2011; 24:297-304. [DOI: 10.1007/s10334-011-0264-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Revised: 06/03/2011] [Accepted: 06/08/2011] [Indexed: 01/01/2023]
|
41
|
Bohte AE, van Werven JR, Bipat S, Stoker J. The diagnostic accuracy of US, CT, MRI and 1H-MRS for the evaluation of hepatic steatosis compared with liver biopsy: a meta-analysis. Eur Radiol 2010; 21:87-97. [PMID: 20680289 PMCID: PMC2995875 DOI: 10.1007/s00330-010-1905-5] [Citation(s) in RCA: 367] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Revised: 05/24/2010] [Accepted: 06/14/2010] [Indexed: 12/11/2022]
Abstract
Objective To meta-analyse the diagnostic accuracy of US, CT, MRI and 1H-MRS for the evaluation of hepatic steatosis. Methods From a comprehensive literature search in MEDLINE, EMBASE, CINAHL and Cochrane (up to November 2009), articles were selected that investigated the diagnostic performance imaging techniques for evaluating hepatic steatosis with histopathology as the reference standard. Cut-off values for the presence of steatosis on liver biopsy were subdivided into four groups: (1) >0, >2 and >5% steatosis; (2) >10, >15 and >20%; (3) >25, >30 and >33%; (4) >50, >60 and >66%. Per group, summary estimates for sensitivity and specificity were calculated. The natural-logarithm of the diagnostic odds ratio (lnDOR) was used as a single indicator of test performance. Results 46 articles were included. Mean sensitivity estimates for subgroups were 73.3–90.5% (US), 46.1–72.0% (CT), 82.0–97.4% (MRI) and 72.7–88.5% (1H-MRS). Mean specificity ranges were 69.6–85.2% (US), 88.1–94.6% (CT), 76.1–95.3% (MRI) and 92.0–95.7% (1H-MRS). Overall performance (lnDOR) of MRI and 1H-MRS was better than that for US and CT for all subgroups, with significant differences in groups 1 and 2. Conclusion MRI and 1H-MRS can be considered techniques of choice for accurate evaluation of hepatic steatosis. Electronic supplementary material The online version of this article (doi:10.1007/s00330-010-1905-5) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Anneloes E Bohte
- Department of Radiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
| | | | | | | |
Collapse
|