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Gerhalter T, Schilling F, Zeitouni N, Linz P, Baudin PY, Kannenkeril D, Kopp C, Dahlmann A, Schmieder R, Uder M, Nagel AM, Gast LV. Sodium quantification in skeletal muscle: comparison between Cartesian gradient-echo and radial ultra-short echo time 23Na MRI techniques. Eur Radiol Exp 2024; 8:61. [PMID: 38773044 PMCID: PMC11109078 DOI: 10.1186/s41747-024-00461-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Accepted: 03/20/2024] [Indexed: 05/23/2024] Open
Abstract
BACKGROUND Clinical magnetic resonance imaging (MRI) studies often use Cartesian gradient-echo (GRE) sequences with ~2-ms echo times (TEs) to monitor apparent total sodium concentration (aTSC). We compared Cartesian GRE and ultra-short echo time three-dimensional (3D) radial-readout sequences for measuring skeletal muscle aTSC. METHODS We retrospectively evaluated 211 datasets from 112 volunteers aged 62.3 ± 12.1 years (mean ± standard deviation), acquired at 3 T from the lower leg. For 23Na MRI acquisitions, we used a two-dimensional Cartesian GRE sequence and a density-adapted 3D radial readout sequence with cuboid field-of-view (DA-3D-RAD-C). We calibrated the 23Na MR signal using reference tubes either with or without agarose and subsequently performed a relaxation correction. Additionally, we employed a six-echo 1H GRE sequence and a multi-echo spin-echo sequence to calculate proton density fat fraction (PDFF) and water T2. Paired Wilcoxon signed-rank test, Cohen dz for paired samples, and Spearman correlation were used. RESULTS Relaxation correction effectively reduced the differences in muscle aTSC between the two acquisition and calibration methods (DA-3D-RAD-C using NaCl/agarose references: 20.05 versus 19.14 mM; dz = 0.395; Cartesian GRE using NaCl/agarose references: 19.50 versus 18.82 mM; dz = 0.427). Both aTSC of the DA-3D-RAD-C and Cartesian GRE acquisitions showed a small but significant correlation with PDFF as well as with water T2. CONCLUSIONS Different 23Na MRI acquisition and calibration approaches affect aTSC values. Applying relaxation correction is advised to minimize the impact of sequence parameters on quantification, and considering additional fat correction is advisable for patients with increased fat fractions. RELEVANCE STATEMENT This study highlights relaxation correction's role in improving sodium MRI accuracy, paving the way for better disease assessment and comparability of measured sodium signal in patients. KEY POINTS • Differences in MRI acquisition methods hamper the comparability of sodium MRI measurements. • Measured sodium values depend on used MRI sequences and calibration method. • Relaxation correction during postprocessing mitigates these discrepancies. • Thus, relaxation correction enhances accuracy of sodium MRI, aiding its clinical use.
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Affiliation(s)
- Teresa Gerhalter
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Maximiliansplatz 3, 91054, Erlangen, Germany.
| | - Felix Schilling
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Maximiliansplatz 3, 91054, Erlangen, Germany
| | - Nour Zeitouni
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Maximiliansplatz 3, 91054, Erlangen, Germany
| | - Peter Linz
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Maximiliansplatz 3, 91054, Erlangen, Germany
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Pierre-Yves Baudin
- NMR laboratory, Neuromuscular Investigation Center, Institute of Myology, Paris, France
| | - Dennis Kannenkeril
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Christoph Kopp
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Anke Dahlmann
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Roland Schmieder
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Michael Uder
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Maximiliansplatz 3, 91054, Erlangen, Germany
| | - Armin M Nagel
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Maximiliansplatz 3, 91054, Erlangen, Germany
- Division of Medical Physics in Radiology, German Cancer Research Centre (DKFZ), Heidelberg, Germany
| | - Lena V Gast
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Maximiliansplatz 3, 91054, Erlangen, Germany
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Gast LV, Platt T, Nagel AM, Gerhalter T. Recent technical developments and clinical research applications of sodium ( 23Na) MRI. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2023; 138-139:1-51. [PMID: 38065665 DOI: 10.1016/j.pnmrs.2023.04.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 04/11/2023] [Accepted: 04/13/2023] [Indexed: 12/18/2023]
Abstract
Sodium is an essential ion that plays a central role in many physiological processes including the transmembrane electrochemical gradient and the maintenance of the body's homeostasis. Due to the crucial role of sodium in the human body, the sodium nucleus is a promising candidate for non-invasively assessing (patho-)physiological changes. Almost 10 years ago, Madelin et al. provided a comprehensive review of methods and applications of sodium (23Na) MRI (Madelin et al., 2014) [1]. More recent review articles have focused mainly on specific applications of 23Na MRI. For example, several articles covered 23Na MRI applications for diseases such as osteoarthritis (Zbyn et al., 2016, Zaric et al., 2020) [2,3], multiple sclerosis (Petracca et al., 2016, Huhn et al., 2019) [4,5] and brain tumors (Schepkin, 2016) [6], or for imaging certain organs such as the kidneys (Zollner et al., 2016) [7], the brain (Shah et al., 2016, Thulborn et al., 2018) [8,9], and the heart (Bottomley, 2016) [10]. Other articles have reviewed technical developments such as radiofrequency (RF) coils for 23Na MRI (Wiggins et al., 2016, Bangerter et al., 2016) [11,12], pulse sequences (Konstandin et al., 2014) [13], image reconstruction methods (Chen et al., 2021) [14], and interleaved/simultaneous imaging techniques (Lopez Kolkovsky et al., 2022) [15]. In addition, 23Na MRI topics have been covered in review articles with broader topics such as multinuclear MRI or ultra-high-field MRI (Niesporek et al., 2019, Hu et al., 2019, Ladd et al., 2018) [16-18]. During the past decade, various research groups have continued working on technical improvements to sodium MRI and have investigated its potential to serve as a diagnostic and prognostic tool. Clinical research applications of 23Na MRI have covered a broad spectrum of diseases, mainly focusing on the brain, cartilage, and skeletal muscle (see Fig. 1). In this article, we aim to provide a comprehensive summary of methodological and hardware developments, as well as a review of various clinical research applications of sodium (23Na) MRI in the last decade (i.e., published from the beginning of 2013 to the end of 2022).
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Affiliation(s)
- Lena V Gast
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany.
| | - Tanja Platt
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany.
| | - Armin M Nagel
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany; Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany.
| | - Teresa Gerhalter
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany.
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Rasmussen CW, Bøgh N, Bech SK, Thorsen TH, Hansen ESS, Bertelsen LB, Laustsen C. Fibrosis imaging with multiparametric proton and sodium MRI in pig injury models. NMR IN BIOMEDICINE 2023; 36:e4838. [PMID: 36151711 PMCID: PMC10078455 DOI: 10.1002/nbm.4838] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 09/10/2022] [Accepted: 09/12/2022] [Indexed: 05/10/2023]
Abstract
Chronic kidney disease (CKD) is common and has huge implications for health and mortality. It is aggravated by intrarenal fibrosis, but the assessment of fibrosis is limited to kidney biopsies, which carry a risk of complications and sampling errors. This calls for a noninvasive modality for diagnosing and staging intrarenal fibrosis. The current, exploratory study evaluates a multiparametric MRI protocol including sodium imaging (23 Na-MRI) to determine the opportunities within this modality to assess kidney injury as a surrogate endpoint of fibrosis. The study includes 43 pigs exposed to ischemia-reperfusion injury (IRI) or unilateral ureteral obstruction (UUO), or serving as healthy controls. Fibrosis was determined using gene expression analysis of collagen. The medulla/cortex ratio of 23 Na-MRI decreased in the injured kidney in the IRI pigs, but not in the UUO pigs (p = 0.0180, p = 0.0754). To assess the combination of MRI parameters in estimating fibrosis, we created a linear regression model consisting of the cortical apparent diffusion coefficient, ΔR2*, ΔT1, the 23 Na medulla/cortex ratio, and plasma creatinine (R2 = 0.8009, p = 0.0117). The 23 Na medulla/cortex ratio only slightly improved the fibrosis prediction model, leaving 23 Na-MRI in an ambiguous place for evaluation of intrarenal fibrosis. Use of multiparametric MRI in combination with plasma creatinine shows potential for the estimation of fibrosis in human kidney disease, but more translational and clinical work is warranted before MRI can contribute to earlier diagnosis and evaluation of treatment for acute kidney injury and CKD.
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Affiliation(s)
- Camilla W. Rasmussen
- The MR Research Center, Department of Clinical MedicineAarhus UniversityAarhusDenmark
| | - Nikolaj Bøgh
- The MR Research Center, Department of Clinical MedicineAarhus UniversityAarhusDenmark
| | - Sabrina K. Bech
- The MR Research Center, Department of Clinical MedicineAarhus UniversityAarhusDenmark
| | - Thomas H. Thorsen
- The MR Research Center, Department of Clinical MedicineAarhus UniversityAarhusDenmark
| | - Esben S. S. Hansen
- The MR Research Center, Department of Clinical MedicineAarhus UniversityAarhusDenmark
| | - Lotte B. Bertelsen
- The MR Research Center, Department of Clinical MedicineAarhus UniversityAarhusDenmark
| | - Christoffer Laustsen
- The MR Research Center, Department of Clinical MedicineAarhus UniversityAarhusDenmark
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Müller HP, Nagel AM, Keidel F, Wunderlich A, Hübers A, Gast LV, Ludolph AC, Beer M, Kassubek J. Relaxation-weighted 23Na magnetic resonance imaging maps regional patterns of abnormal sodium concentrations in amyotrophic lateral sclerosis. Ther Adv Chronic Dis 2022; 13:20406223221109480. [PMID: 35837670 PMCID: PMC9274400 DOI: 10.1177/20406223221109480] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 06/01/2022] [Indexed: 11/30/2022] Open
Abstract
Objectives: Multiparametric magnetic resonance imaging (MRI) is established as a
technical instrument for the characterisation of patients with amyotrophic
lateral sclerosis (ALS). The contribution of relaxation-weighted sodium
(23NaR) MRI remains to be defined. The aim of this study is
to apply 23NaR MRI to investigate brain sodium homeostasis and
map potential alterations in patients with ALS as compared with healthy
controls. Materials and Methods: Seventeen patients with ALS (mean age 61.1 ± 11.4 years, m/f = 9/8) and 10
healthy control subjects (mean age 60.3 ± 15.3 years, m/f = 6/4) were
examined by 23NaR MRI at 3 T. Regional sodium maps were obtained
by the calculation of the weighted difference from two image data sets with
different echo times (TE1 = 0.3 ms, TE2 = 25 ms).
Voxel-based analysis of the relaxation-weighted maps, together with
23Na concentration maps for comparison, was performed. Results: ROI-based analyses of relaxation-weighted brain sodium concentration maps
demonstrated increased sodium concentrations in the upper corticospinal
tracts and in the frontal lobes in patients with ALS; no differences between
ALS patients and controls were found in reference ROIs, where no involvement
in ALS-associated neurodegeneration could be anticipated. Conclusion: 23NaR MRI mapped regional alterations within disease-relevant
areas in ALS which correspond to the stages of the central nervous system
(CNS) pathology, providing evidence that the technique is a potential
biological marker of the cerebral neurodegenerative process in ALS.
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Affiliation(s)
| | - Armin M Nagel
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Franziska Keidel
- Department of Diagnostic and Interventional Radiology, University of Ulm, Ulm, Germany
| | - Arthur Wunderlich
- Department of Diagnostic and Interventional Radiology, University of Ulm, Ulm, Germany
| | | | - Lena V Gast
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Albert C Ludolph
- Department of Neurology, University of Ulm, Ulm, Germany German Center for Neurodegenerative Diseases (DZNE), Ulm, Germany
| | - Meinrad Beer
- Department of Diagnostic and Interventional Radiology, University of Ulm, Ulm, Germany
| | - Jan Kassubek
- Department of Neurology, University of Ulm, Oberer Eselsberg 45, Ulm 89081, Germany
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Tomiyasu M, Harada M. In vivo Human MR Spectroscopy Using a Clinical Scanner: Development, Applications, and Future Prospects. Magn Reson Med Sci 2022; 21:235-252. [PMID: 35173095 PMCID: PMC9199975 DOI: 10.2463/mrms.rev.2021-0085] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
MR spectroscopy (MRS) is a unique and useful method for noninvasively evaluating biochemical metabolism in human organs and tissues, but its clinical dissemination has been slow and often limited to specialized institutions or hospitals with experts in MRS technology. The number of 3-T clinical MR scanners is now increasing, representing a major opportunity to promote the use of clinical MRS. In this review, we summarize the theoretical background and basic knowledge required to understand the results obtained with MRS and introduce the general consensus on the clinical utility of proton MRS in routine clinical practice. In addition, we present updates to the consensus guidelines on proton MRS published by the members of a working committee of the Japan Society of Magnetic Resonance in Medicine in 2013. Recent research into multinuclear MRS equipped in clinical MR scanners is explained with an eye toward future development. This article seeks to provide an overview of the current status of clinical MRS and to promote the understanding of when it can be useful. In the coming years, MRS-mediated biochemical evaluation is expected to become available for even routine clinical practice.
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Affiliation(s)
- Moyoko Tomiyasu
- Department of Molecular Imaging and Theranostics, National Institutes for Quantum Science and Technology.,Department of Radiology, Kanagawa Children's Medical Center
| | - Masafumi Harada
- Department of Radiology and Radiation Oncology, Graduate School of Biomedical Sciences, Tokushima University
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Polak P, Schulte RF, Noseworthy MD. An approach to evaluation of the point-spread function for 23 Na magnetic resonance imaging. NMR IN BIOMEDICINE 2022; 35:e4627. [PMID: 34652040 DOI: 10.1002/nbm.4627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 08/28/2021] [Accepted: 09/11/2021] [Indexed: 06/13/2023]
Abstract
Despite the technical challenges that require lengthy acquisitions to overcome poor signal-to-noise ratio (SNR), sodium (23 Na) magnetic resonance imaging (MRI) is an intriguing area of research due to its essential role in human metabolism. Low SNR images can impact the measurement of the point-spread function (PSF) by adding uncertainty into the resulting quantities. Here, we present methods to calculate the PSF by using the modulation transfer function (MTF), and a 3D-printed line-pair phantom in the context of 23 Na MRI. A simulation study investigated the effect of noise on the resulting MTF curves, which were derived by direct modulation (DM) and a method utilizing Fourier harmonics (FHs). Experimental data utilized a line-pair phantom with nine spatial frequencies, filled with different concentrations (15, 30, and 60 mM) of sodium in 3% agar. MTF curves were calculated using both methods from data acquired from density-adapted 3D radial projections (DA-3DRP) and Fermat looped orthogonally encoded trajectories (FLORET). Simulations indicated that the DM method increased variability in the MTF curves at all tested noise levels over the FH method. For the experimental data, the FH method resulted in PSFs with a narrower full width half maximum with reduced variability, although the improvement in variability was not as pronounced as predicted by simulations. The DA-3DRP data indicated an improvement in the PSF over FLORET. It was concluded that a 3D-printed line-pair phantom represents a convenient method to measure the PSF experimentally. The MTFs from the noisy images in 23 Na MRI have reduced variability from a FH method over DM.
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Affiliation(s)
- Paul Polak
- School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada
- Imaging Research Centre, St. Joseph's Healthcare, Hamilton, Ontario, Canada
| | | | - Michael D Noseworthy
- School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada
- Imaging Research Centre, St. Joseph's Healthcare, Hamilton, Ontario, Canada
- Electrical and Computer Engineering, McMaster University, Hamilton, Ontario, Canada
- Department of Radiology, McMaster University, Hamilton, Ontario, Canada
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Mennecke AB, Nagel AM, Huhn K, Linker RA, Schmidt M, Rothhammer V, Wilferth T, Linz P, Wegmann J, Eisenhut F, Engelhorn T, Doerfler A. Longitudinal Sodium MRI of Multiple Sclerosis Lesions: Is there Added Value of Sodium Inversion Recovery MRI. J Magn Reson Imaging 2021; 55:140-151. [PMID: 34259373 DOI: 10.1002/jmri.27832] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 06/25/2021] [Accepted: 06/29/2021] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Sodium enhancement has been demonstrated in multiple sclerosis (MS) lesions. PURPOSE To investigate sodium MRI with and without an inversion recovery pulse in acute MS lesions in an MS relapse and during recovery. STUDY TYPE Prospective. SUBJECTS Twenty-nine relapsing-remitting MS patients with an acute relapse were included. FIELD STRENGTH/SEQUENCE A 3D density-adapted radial sodium sequence at 3 T using a dual-tuned (23 Na/1 H) head coil. ASSESSMENT Full-brain images of the tissue sodium concentration (TSC1, n = 29) and a sodium inversion recovery sequence (SIR1, n = 20) at the beginning of the anti-inflammatory therapy and on medium-term follow-up visits (days 27-99, n = 12 [TSC], n = 5 [SIR]) were measured. Regions of interest (RoIs) with contrast enhancement (T1 CE+) and without change in T1-weighted imaging (FL + T1n) were normalized (nTSC and nSIR). To gain insight on the origin of the TSC enhancement at time point 1, it is investigated whether the nTSC enhancement of the lesions is accompanied by a change of the respective nSIR. Potential prognostic value of nSIR1 is examined referring to the nTSC progression. STATISTICAL TESTS: nTSC and nSIR were compared regarding the type of lesion and the time point using a one-way ANOVA. Pearson's correlation coefficient was calculated for nTSC over nSIR and for nTSC1-nTSC2 over nSIR1. A P-value <0.05 was considered statistically significant. RESULTS At the first measurement, all lesion types showed increased nTSC, while nSIR was decreased in the FL + T1 n and the T1 CE+ lesions in comparison to the normal-appearing white matter. For acute lesions, the difference between nTSC at baseline and nTSC at time point 2 showed a significant correlation with the baseline nSIR. DATA CONCLUSION At time point 1, nTSC is increased, while nSIR is unchanged or decreased in the lesions. The mean sodium IR signal at baseline correlates with recovery or progression of an acute lesion. EVIDENCE LEVEL 2 TECHNICAL EFFICACY: Stage 4.
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Affiliation(s)
- Angelika B Mennecke
- Department of Neuroradiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Armin M Nagel
- Institute of Radiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany.,Division of Medical Physics in Radiology, German Cancer Research Centre (DKFZ), Heidelberg, Germany
| | - Konstantin Huhn
- Department of Neurology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Ralf A Linker
- Department of Neurology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany.,Department of Neurology, University Clinic Regensburg, Germany
| | - Manuel Schmidt
- Department of Neuroradiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Veit Rothhammer
- Department of Neurology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Tobias Wilferth
- Institute of Radiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Peter Linz
- Institute of Radiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Julius Wegmann
- Department of Neuroradiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Felix Eisenhut
- Department of Neuroradiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Tobias Engelhorn
- Department of Neuroradiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Arnd Doerfler
- Department of Neuroradiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
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Abstract
BACKGROUND X‑nuclei magnetic resonance imaging (MRI) yields a broad spectrum of metabolic and functional imaging techniques with increasing clinical feasibility. OBJECTIVE Current X‑nuclei techniques in (neuro)oncology with emphasis on potential clinical applications of sodium and oxygen MRI are described and discussed. MATERIALS AND METHODS Review with discussion of state-of-the-art literature on X‑nuclei imaging. RESULTS X‑nuclei MRI employs NMR-sensitive nonproton nuclei to enable both anatomical visualization as well as noninvasive imaging and quantification of physiological processes in the human body. At the moment, sodium MRI represents the most common application of X‑nuclei MRI because of its comparatively high NMR signal. Moreover, its sensitivity to pathological cellular proliferation renders sodium MRI a good candidate for oncological imaging, yielding additional biochemical information to proton MRI. Oxygen MRI is currently primarily investigational, requiring high technical efforts and costs. However, preliminary results show a huge potential of this technique for metabolic characterization of tumors. CONCLUSIONS X‑nuclei MRI is a rapidly evolving field in metabolic and functional imaging. In coming years, sodium MRI is expected to be increasingly used as an additional clinical tool in oncology to enhance diagnostic accuracy.
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Sodium ( 23Na) MRI of the Kidney: Basic Concept. Methods Mol Biol 2021; 2216:257-266. [PMID: 33476005 DOI: 10.1007/978-1-0716-0978-1_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The handling of sodium by the renal system is a key indicator of renal function. Alterations in the corticomedullary distribution of sodium are considered important indicators of pathology in renal diseases. The derangement of sodium handling can be noninvasively imaged using sodium magnetic resonance imaging (23Na MRI), with data analysis allowing for the assessment of the corticomedullary sodium gradient. Here we introduce sodium imaging, describe the existing methods, and give an overview of preclinical sodium imaging applications to illustrate the utility and applicability of this technique for measuring renal sodium handling.This chapter is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This introduction chapter is complemented by two separate chapters describing the experimental procedure and data analysis.
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10
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Wilcox M, Wright SM, McDougall M. A Review of Non- 1H RF Receive Arrays in Magnetic Resonance Imaging and Spectroscopy. IEEE OPEN JOURNAL OF ENGINEERING IN MEDICINE AND BIOLOGY 2020; 1:290-300. [PMID: 35402958 PMCID: PMC8975242 DOI: 10.1109/ojemb.2020.3030531] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 09/15/2020] [Accepted: 09/25/2020] [Indexed: 11/16/2022] Open
Abstract
It is now common practice to use radiofrequency (RF) coils to increase the signal-to-noise ratio (SNR) in 1H magnetic resonance imaging and spectroscopy experiments. Use of array coils for non-1H experiments, however, has been historically more limited despite the fact that these nuclei suffer inherently lower sensitivity and could benefit greatly from an increased SNR. Recent advancements in receiver technology and increased support from scanner manufacturers have now opened greater options for the use of array coils for non-1H magnetic resonance experiments. This paper reviews the research in adopting array coil technology with an emphasis on studies of the most commonly studied non-1H nuclei including 31P, 13C, 23Na, and 19F. These nuclei offer complementary information to 1H imaging and spectroscopy and have proven themselves important in the study of numerous disease processes. While recent work with non-1H array coils has shown promising results, the technology is not yet widely utilized and should see substantial developments in the coming years.
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11
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Utzschneider M, Müller M, Gast LV, Lachner S, Behl NGR, Maier A, Uder M, Nagel AM. Towards accelerated quantitative sodium MRI at 7 T in the skeletal muscle: Comparison of anisotropic acquisition- and compressed sensing techniques. Magn Reson Imaging 2020; 75:72-88. [PMID: 32979516 DOI: 10.1016/j.mri.2020.09.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 08/25/2020] [Accepted: 09/14/2020] [Indexed: 12/14/2022]
Abstract
PURPOSE To compare three anisotropic acquisition schemes and three compressed sensing (CS) approaches for accelerated tissue sodium concentration (TSC) quantification using 23Na MRI at 7 T. MATERIALS AND METHODS Three anisotropic 3D-radial acquisition sequences were evaluated using simulations, phantom- and in vivo TSC measurements: An anisotropic density-adapted 3D-radial sequence (3DPR-C), a 3D acquisition-weighted density-adapted stack-of-stars sampling scheme (SOS) and a SOS approach with golden-ratio rotation (SOS-GR). Eight healthy volunteers were examined at a 7 Tesla MRI system. TSC measurements of the calf were conducted with a nominal spatial resolution of Δx = (3.0 × 3.0 × 15.0) mm3 and a field of view of (156.0 × 156.0 × 240.0) mm3 for multiple undersampling factors (USF). Three CS reconstructions were evaluated: Total variation CS (TV-CS), 3D dictionary-learning compressed sensing (3D-DLCS) and TV-CS with a block matching prior (TV-BL-CS). Results of the simulations and measurements were compared to a simulated ground truth (GT) or a fully sampled reference measurement (FS), respectively. The deviation of the mean TSC evaluated in multiple ROI (mEGT/FS) and the normalized root-mean-squared error (NRMSE) for simulations were evaluated for CS and NUFFT reconstructions. RESULTS In simulations, the SOS-GR yielded the lowest NRMSE and mEGT (< 4%) with NUFFT for an acquisition time (TA) of less than 2 min. CS further improved the results. In simulations and measurements, the best TSC quantification results were obtained with 3D-DLCS and SOS-GR (lowest NRMSE, mEGT < 2.6% in simulations, mEGT < 10.7% for phantom measurements and mEFS < 6% in vivo) with an USF = 4.1 (TA < 2 min). TV-CS showed no or only slight improvements to NUFFT. The results of TV-BL-CS were similar to 3D-DLCS. DISCUSSION The TA for TSC measurements could be reduced to less than 2 min by using adapted sequences such as SOS-GR and CS reconstruction approaches such as 3D-DLCS or TV-BL-CS, while the quantitative accuracy stays comparable to a fully sampled NUFFT reconstruction (approx. 8 min TA). In future, the lower TA could improve clinical applicability of TSC measurements.
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Affiliation(s)
- Matthias Utzschneider
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany; Pattern Recognition Lab, Department of Computer Science, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany.
| | - Max Müller
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Lena V Gast
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany; Institute of Medical Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Sebastian Lachner
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Nicolas G R Behl
- Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Andreas Maier
- Pattern Recognition Lab, Department of Computer Science, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Michael Uder
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Armin M Nagel
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany; Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Institute of Medical Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
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12
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Gerhalter T, Gast LV, Marty B, Uder M, Carlier PG, Nagel AM. Assessing the variability of 23 Na MRI in skeletal muscle tissue: Reproducibility and repeatability of tissue sodium concentration measurements in the lower leg at 3 T. NMR IN BIOMEDICINE 2020; 33:e4279. [PMID: 32125054 DOI: 10.1002/nbm.4279] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 12/10/2019] [Accepted: 01/27/2020] [Indexed: 06/10/2023]
Abstract
The goal of this study was to evaluate the reproducibility and repeatability of tissue sodium concentration (TSC) measurements using 23 Na MRI in skeletal muscle tissue. 23 Na MRI was performed at 3 T on the right lower leg of eight healthy volunteers (aged 28 ± 4 years). The examinations were repeated at the same site after ~ 22 weeks to assess the variability over a medium-term period. Additionally, they were scanned at a second site shortly before or shortly after the first visit (within 3 weeks) to evaluate the inter-site reproducibility. Moreover, we analysed the effect of B0 correction on the variability. Coefficients of variations (CVs) from mean TSC values as well as Bland-Altman plots were used to assess intra-site repeatability and inter-site reproducibility. In phantom measurements, the B0 correction improved the quantitative accuracy. We observed differences of up to 4.9 mmol/L between the first and second visit and a difference of up to 3.7 mmol/L between the two different sites. The CV for the medium-term repeatability was 15% and the reproducibility CV was 9%. The Bland-Altman plots indicated high agreement between the visits in all muscle regions. The systematic bias of -0.68 mmol/L between site X and Y (P = 0.03) was slightly reduced to -0.64 mmol/L after B0 correction (P = 0.04). This work shows that TSC measurements in healthy skeletal muscle tissue can be performed with good repeatability and reproducibility, which is of importance for future longitudinal or multicentre studies.
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Affiliation(s)
- Teresa Gerhalter
- Institute of Radiology, University Hospital Erlangen, FAU, Erlangen, Germany
- NMR laboratory, Institute of Myology, Paris, France
- NMR laboratory, CEA/DRF/IBFJ/MIRCen, Paris, France
| | - Lena V Gast
- Institute of Radiology, University Hospital Erlangen, FAU, Erlangen, Germany
| | - Benjamin Marty
- NMR laboratory, Institute of Myology, Paris, France
- NMR laboratory, CEA/DRF/IBFJ/MIRCen, Paris, France
| | - Michael Uder
- Institute of Radiology, University Hospital Erlangen, FAU, Erlangen, Germany
| | - Pierre G Carlier
- NMR laboratory, Institute of Myology, Paris, France
- NMR laboratory, CEA/DRF/IBFJ/MIRCen, Paris, France
| | - Armin M Nagel
- Institute of Radiology, University Hospital Erlangen, FAU, Erlangen, Germany
- Division of Medical Physics in Radiology,, DKFZ, Heidelberg, Germany
- Institute of Medical Physics FAU, Erlangen, Germany
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13
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Poku LO, Phil M, Cheng Y, Wang K, Sun X. 23 Na-MRI as a Noninvasive Biomarker for Cancer Diagnosis and Prognosis. J Magn Reson Imaging 2020; 53:995-1014. [PMID: 32219933 PMCID: PMC7984266 DOI: 10.1002/jmri.27147] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 03/06/2020] [Accepted: 03/07/2020] [Indexed: 12/11/2022] Open
Abstract
The influx of sodium (Na+) ions into a resting cell is regulated by Na+ channels and by Na+/H+ and Na+/Ca2+ exchangers, whereas Na+ ion efflux is mediated by the activity of Na+/K+‐ATPase to maintain a high transmembrane Na+ ion gradient. Dysfunction of this system leads to changes in the intracellular sodium concentration that promotes cancer metastasis by mediating invasion and migration. In addition, the accumulation of extracellular Na+ ions in cancer due to inflammation contributes to tumor immunogenicity. Thus, alterations in the Na+ ion concentration may potentially be used as a biomarker for malignant tumor diagnosis and prognosis. However, current limitations in detection technology and a complex tumor microenvironment present significant challenges for the in vivo assessment of Na+ concentration in tumor. 23Na‐magnetic resonance imaging (23Na‐MRI) offers a unique opportunity to study the effects of Na+ ion concentration changes in cancer. Although challenged by a low signal‐to‐noise ratio, the development of ultrahigh magnetic field scanners and specialized sodium acquisition sequences has significantly advanced 23Na‐MRI. 23Na‐MRI provides biochemical information that reflects cell viability, structural integrity, and energy metabolism, and has been shown to reveal rapid treatment response at the molecular level before morphological changes occur. Here we review the basis of 23Na‐MRI technology and discuss its potential as a direct noninvasive in vivo diagnostic and prognostic biomarker for cancer therapy, particularly in cancer immunotherapy. We propose that 23Na‐MRI is a promising method with a wide range of applications in the tumor immuno‐microenvironment research field and in cancer immunotherapy monitoring. Level of Evidence 2 Technical Efficacy Stage 2
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Affiliation(s)
| | - M Phil
- NHC and CAMS Key Laboratory of Molecular Probe and Targeted Theranostics, Harbin Medical University, Harbin, China.,Molecular Imaging Research Center (MIRC), Harbin Medical University, Harbin, China.,TOF-PET/CT/MR Center, The Fourth Hospital of Harbin Medical University, Harbin, China
| | - Yongna Cheng
- NHC and CAMS Key Laboratory of Molecular Probe and Targeted Theranostics, Harbin Medical University, Harbin, China.,Molecular Imaging Research Center (MIRC), Harbin Medical University, Harbin, China.,TOF-PET/CT/MR Center, The Fourth Hospital of Harbin Medical University, Harbin, China
| | - Kai Wang
- NHC and CAMS Key Laboratory of Molecular Probe and Targeted Theranostics, Harbin Medical University, Harbin, China.,Molecular Imaging Research Center (MIRC), Harbin Medical University, Harbin, China.,TOF-PET/CT/MR Center, The Fourth Hospital of Harbin Medical University, Harbin, China
| | - Xilin Sun
- NHC and CAMS Key Laboratory of Molecular Probe and Targeted Theranostics, Harbin Medical University, Harbin, China.,Molecular Imaging Research Center (MIRC), Harbin Medical University, Harbin, China.,TOF-PET/CT/MR Center, The Fourth Hospital of Harbin Medical University, Harbin, China
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14
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Utzschneider M, Behl NGR, Lachner S, Gast LV, Maier A, Uder M, Nagel AM. Accelerated quantification of tissue sodium concentration in skeletal muscle tissue: quantitative capability of dictionary learning compressed sensing. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2020; 33:495-505. [DOI: 10.1007/s10334-019-00819-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 11/22/2019] [Accepted: 12/17/2019] [Indexed: 12/11/2022]
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15
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Strijkers GJ, Araujo EC, Azzabou N, Bendahan D, Blamire A, Burakiewicz J, Carlier PG, Damon B, Deligianni X, Froeling M, Heerschap A, Hollingsworth KG, Hooijmans MT, Karampinos DC, Loudos G, Madelin G, Marty B, Nagel AM, Nederveen AJ, Nelissen JL, Santini F, Scheidegger O, Schick F, Sinclair C, Sinkus R, de Sousa PL, Straub V, Walter G, Kan HE. Exploration of New Contrasts, Targets, and MR Imaging and Spectroscopy Techniques for Neuromuscular Disease - A Workshop Report of Working Group 3 of the Biomedicine and Molecular Biosciences COST Action BM1304 MYO-MRI. J Neuromuscul Dis 2020; 6:1-30. [PMID: 30714967 PMCID: PMC6398566 DOI: 10.3233/jnd-180333] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Neuromuscular diseases are characterized by progressive muscle degeneration and muscle weakness resulting in functional disabilities. While each of these diseases is individually rare, they are common as a group, and a large majority lacks effective treatment with fully market approved drugs. Magnetic resonance imaging and spectroscopy techniques (MRI and MRS) are showing increasing promise as an outcome measure in clinical trials for these diseases. In 2013, the European Union funded the COST (co-operation in science and technology) action BM1304 called MYO-MRI (www.myo-mri.eu), with the overall aim to advance novel MRI and MRS techniques for both diagnosis and quantitative monitoring of neuromuscular diseases through sharing of expertise and data, joint development of protocols, opportunities for young researchers and creation of an online atlas of muscle MRI and MRS. In this report, the topics that were discussed in the framework of working group 3, which had the objective to: Explore new contrasts, new targets and new imaging techniques for NMD are described. The report is written by the scientists who attended the meetings and presented their data. An overview is given on the different contrasts that MRI can generate and their application, clinical needs and desired readouts, and emerging methods.
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Affiliation(s)
| | - Ericky C.A. Araujo
- NMR Laboratory, Neuromuscular Investigation Center, Institute of Myology & NMR Laboratory, CEA/DRF/IBFJ/MIRCen, Paris, France
| | - Noura Azzabou
- NMR Laboratory, Neuromuscular Investigation Center, Institute of Myology & NMR Laboratory, CEA/DRF/IBFJ/MIRCen, Paris, France
| | | | - Andrew Blamire
- Institute of Cellular Medicine, Newcastle University, Newcastle-upon-Tyne, UK
| | - Jedrek Burakiewicz
- Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands
| | - Pierre G. Carlier
- NMR Laboratory, Neuromuscular Investigation Center, Institute of Myology & NMR Laboratory, CEA/DRF/IBFJ/MIRCen, Paris, France
| | - Bruce Damon
- Vanderbilt University Medical Center, Nashville, USA
| | - Xeni Deligianni
- Department of Radiology, Division of Radiological Physics, University Hospital Basel, Basel, Switzerland & Department of Biomedical Engineering, University of Basel, Basel, Switzerland
| | | | - Arend Heerschap
- Radboud University Medical Center, Nijmegen, the Netherlands
| | | | | | | | | | | | - Benjamin Marty
- NMR Laboratory, Neuromuscular Investigation Center, Institute of Myology & NMR Laboratory, CEA/DRF/IBFJ/MIRCen, Paris, France
| | - Armin M. Nagel
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany & Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | | | | | - Francesco Santini
- Department of Radiology, Division of Radiological Physics, University Hospital Basel, Basel, Switzerland & Department of Biomedical Engineering, University of Basel, Basel, Switzerland
| | - Olivier Scheidegger
- Department of Neurology, Inselspital, Bern University Hospital, University of Bern, Switzerland
| | - Fritz Schick
- University of Tübingen, Section on Experimental Radiology, Tübingen, Germany
| | | | | | | | - Volker Straub
- Institute of Cellular Medicine, Newcastle University, Newcastle-upon-Tyne, UK
| | | | - Hermien E. Kan
- Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands
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16
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Lachner S, Ruck L, Niesporek SC, Utzschneider M, Lott J, Hensel B, Dörfler A, Uder M, Nagel AM. Comparison of optimized intensity correction methods for 23Na MRI of the human brain using a 32-channel phased array coil at 7 Tesla. Z Med Phys 2019; 30:104-115. [PMID: 31866116 DOI: 10.1016/j.zemedi.2019.10.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 10/21/2019] [Accepted: 10/25/2019] [Indexed: 01/24/2023]
Abstract
PURPOSE To correct for the non-homogeneous receive profile of a phased array head coil in sodium magnetic resonance imaging (23Na MRI). METHODS 23Na MRI of the human brain (n = 8) was conducted on a 7T MR system using a dual-tuned quadrature 1H/23Na transmit/receive birdcage coil, equipped with a 32-channel receive-only array. To correct the inhomogeneous receive profile four different methods were applied: (1) the uncorrected phased array image and an additionally acquired birdcage image as reference image were low-pass filtered and divided by each other. (2) The second method substituted the reference image by a support region. (3) By averaging the individually calculated receive profiles, a universal sensitivity map was obtained and applied. (4) The receive profile was determined by a pre-scanned large uniform phantom. The calculation of the sensitivity maps was optimized in a simulation study using the normalized root-mean-square error (NRMSE). All methods were evaluated in phantom measurements and finally applied to in vivo 23Na MRI data sets. The in vivo measurements were partial volume corrected and for further evaluation the signal ratio between the outer and inner cerebrospinal fluid compartments (CSFout:CSFin) was calculated. RESULTS Phantom measurements show the correction of the intensity profile applying the given methods. Compared to the uncorrected phased array image (NRMSE = 0.46, CSFout:CSFin = 1.71), the quantitative evaluation of simulated and measured intensity corrected human brain data sets indicates the best performance utilizing the birdcage image (NRMSE = 0.39, CSFout:CSFin = 1.00). However, employing a support region (NRMSE = 0.40, CSFout:CSFin = 1.17), a universal sensitivity map (NRMSE = 0.41, CSFout:CSFin = 1.05) or a pre-scanned sensitivity map (NRMSE = 0.42, CSFout:CSFin = 1.07) shows only slightly worse results. CONCLUSION Acquiring a birdcage image as reference image to correct for the receive profile demonstrates the best performance. However, when aiming to reduce acquisition time or for measurements without existing birdcage coil, methods that use a support region as reference image, a universal or a pre-scanned sensitivity map provide good alternatives for correction of the receive profile.
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Affiliation(s)
- Sebastian Lachner
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany.
| | - Laurent Ruck
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Sebastian C Niesporek
- Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Matthias Utzschneider
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Johanna Lott
- Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany; University of Heidelberg, Faculty of Physics and Astronomy, Heidelberg, Germany
| | - Bernhard Hensel
- Center for Medical Physics and Engineering, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Arnd Dörfler
- Department of Neuroradiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Germany
| | - Michael Uder
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Armin M Nagel
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany; Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Institute of Medical Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
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17
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Milani B, Delacoste J, Burnier M, Pruijm M. Exploring a new method for quantitative sodium MRI in the human upper leg with a surface coil and symmetrically arranged reference phantoms. Quant Imaging Med Surg 2019; 9:985-999. [PMID: 31367553 DOI: 10.21037/qims.2019.06.08] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Background The aim of this study is to validate and evaluate the reproducibility of a new setup for the quantification of the tissue sodium concentration (TSC) in the human upper leg muscles with sodium MRI at 3 Tesla. This setup is making use of an emit and receive single loop surface coil together with a set of square, symmetrically arranged reference phantoms. As a second aim, the performances of two MRI protocols for the TSC quantification in the upper leg muscles are compared: one using an ultra-short echo time (UTE) 3-dimensional radial sequence (UTE-protocol), and the other one using standard gradient echo sequence (GRE-protocol). Methods A validation test of the quantification of sodium concentration is performed in phantoms. The bias of the method is estimated and compared between both protocols. The reproducibility of TSC quantification is assessed in phantoms by the coefficient of variation (CV) and compared between both protocols. The reproducibility is also assessed in 11 health volunteers. Signal to noise ratio (SNR) maps are acquired in phantoms with both protocols in order to compare the resulting SNR. Results The apparatus and post processing were successfully implemented. The bias of the method was smaller than 10% in phantoms (excepted for Na concentration of 10 mmol/L when using the GRE protocol). The reproducibility of the method using symmetrically arranged phantoms was high in phantoms and humans (CV <5%). The GRE-protocol leads to a better SNR than the UTE-protocol in 2D images. Conclusions The use of symmetrically arranged reference phantoms lead to reproducible results in phantoms and humans. Sodium imaging in the human upper leg with a single loop surface coil should be performed with a standard 2-dimensional GRE protocol if an optimal SNR is needed. However, the quantification of the fast and slow decay time constants of the sodium signal, which plays a role in the TSC quantification, still has to be done with a UTE sequence. Moreover, the quantification of sodium concentration is more accurate with the UTE protocol for small sodium concentrations (<20 mmol).
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Affiliation(s)
- Bastien Milani
- Division of Nephrology and Hypertension, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland.,Departement de Radiologie, Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland.,Center for Biomedical Imaging (CIBM), Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland
| | - Jean Delacoste
- Departement de Radiologie, Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland.,Center for Biomedical Imaging (CIBM), Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland
| | - Michel Burnier
- Division of Nephrology and Hypertension, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Menno Pruijm
- Division of Nephrology and Hypertension, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
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18
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Meyer MM, Schmidt A, Benrath J, Konstandin S, Pilz LR, Harrington MG, Budjan J, Meyer M, Schad LR, Schoenberg SO, Haneder S. Cerebral sodium ( 23Na) magnetic resonance imaging in patients with migraine - a case-control study. Eur Radiol 2019; 29:7055-7062. [PMID: 31264011 DOI: 10.1007/s00330-019-06299-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 04/21/2019] [Accepted: 06/03/2019] [Indexed: 12/22/2022]
Abstract
OBJECTIVE Evaluation of MRI-derived cerebral 23Na concentrations in patients with migraine in comparison with healthy controls. MATERIALS AND METHODS In this case-control study, 24 female migraine patients (mean age, 34 ± 11 years) were enrolled after evaluation of standardized questionnaires. Half (n = 12) of the cohort suffered from migraine, the other half was impaired by both migraine and tension-type headaches (TTH). The combined patient cohort was matched to 12 healthy female controls (mean age, 34 ± 11 years). All participants underwent a cerebral 23Na-magnetic resonance imaging examination at 3.0 T, which included a T1w MP-RAGE sequence and a 3D density-adapted, radial gradient echo sequence for 23Na imaging. Circular regions of interests were placed in predetermined anatomic regions: cerebrospinal fluid (CSF), gray and white matter, brain stem, and cerebellum. External 23Na reference phantoms were used to calculate the total 23Na tissue concentrations. Pearson's correlation, Kendall Tau, and Wilcoxon rank sum test were used for statistical analysis. RESULTS 23Na concentrations of all patients in the CSF were significantly higher than in healthy controls (p < 0.001). The CSF of both the migraine and mixed migraine/TTH group showed significantly increased sodium concentrations compared to the control group (p = 0.007 and p < 0.001). Within the patient cohort, a positive correlation between pain level and TSC in the CSF (r = 0.62) could be observed. CONCLUSION MRI-derived cerebral 23Na concentrations in the CSF of migraine patients were found to be statistically significantly higher than in healthy controls. KEY POINTS • Cerebral sodium MRI supports the theory of ionic imbalances and may aid in the challenging pathophysiologic understanding of migraine. • Case-control study shows significantly higher sodium concentrations in cerebrospinal fluid of migraineurs. • Cerebral sodium MRI may become a non-invasive imaging tool for drugs to modulate sodium, and hence migraine, on a molecular level, and influence patient management.
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Affiliation(s)
- Melissa M Meyer
- Institute of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany.
| | - Alexander Schmidt
- Institute of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany.,Department of Diagnostic and Interventional Radiology, University of Würzburg, Würzburg, Germany
| | - Justus Benrath
- Clinic for Anaesthesiology and Operative Intensive Care, University of Heidelberg, Mannheim, Germany
| | | | - Lothar R Pilz
- Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | | | - Johannes Budjan
- Institute of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany
| | - Mathias Meyer
- Institute of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany
| | - Lothar R Schad
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Stefan O Schoenberg
- Institute of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany
| | - Stefan Haneder
- Department of Radiology, University Hospital of Cologne, Cologne, Germany
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19
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Lachner S, Zaric O, Utzschneider M, Minarikova L, Zbýň Š, Hensel B, Trattnig S, Uder M, Nagel AM. Compressed sensing reconstruction of 7 Tesla 23Na multi-channel breast data using 1H MRI constraint. Magn Reson Imaging 2019; 60:145-156. [DOI: 10.1016/j.mri.2019.03.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 03/01/2019] [Accepted: 03/29/2019] [Indexed: 12/14/2022]
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20
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Abstract
In this article, an overview of the current developments and research applications for non-proton magnetic resonance imaging (MRI) at ultrahigh magnetic fields (UHFs) is given. Due to technical and methodical advances, efficient MRI of physiologically relevant nuclei, such as Na, Cl, Cl, K, O, or P has become feasible and is of interest to obtain spatially and temporally resolved information that can be used for biomedical and diagnostic applications. Sodium (Na) MRI is the most widespread multinuclear imaging method with applications ranging over all regions of the human body. Na MRI yields the second largest in vivo NMR signal after the clinically used proton signal (H). However, other nuclei such as O and P (energy metabolism) or Cl and K (cell viability) are used in an increasing number of MRI studies at UHF. One major advancement has been the increased availability of whole-body MR scanners with UHFs (B0 ≥7T) expanding the range of detectable nuclei. Nevertheless, efforts in terms of pulse sequence and post-processing developments as well as hardware designs must be made to obtain valuable information in clinically feasible measurement times. This review summarizes the available methods in the field of non-proton UHF MRI, especially for Na MRI, as well as introduces potential applications in clinical research.
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Affiliation(s)
- Sebastian C Niesporek
- Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Armin M Nagel
- Division of 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
- Institute of Medical Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Tanja Platt
- Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
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21
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Hu R, Kleimaier D, Malzacher M, Hoesl MA, Paschke NK, Schad LR. X‐nuclei imaging: Current state, technical challenges, and future directions. J Magn Reson Imaging 2019; 51:355-376. [DOI: 10.1002/jmri.26780] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 04/23/2019] [Accepted: 04/24/2019] [Indexed: 12/16/2022] Open
Affiliation(s)
- Ruomin Hu
- Computer Assisted Clinical MedicineHeidelberg University Mannheim Germany
| | - Dennis Kleimaier
- Computer Assisted Clinical MedicineHeidelberg University Mannheim Germany
| | - Matthias Malzacher
- Computer Assisted Clinical MedicineHeidelberg University Mannheim Germany
| | | | - Nadia K. Paschke
- Computer Assisted Clinical MedicineHeidelberg University Mannheim Germany
| | - Lothar R. Schad
- Computer Assisted Clinical MedicineHeidelberg University Mannheim Germany
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22
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Meyer MM, Haneder S, Konstandin S, Budjan J, Morelli JN, Schad LR, Kerl HU, Schoenberg SO, Kabbasch C. Repeatability and reproducibility of cerebral 23Na imaging in healthy subjects. BMC Med Imaging 2019; 19:26. [PMID: 30943911 PMCID: PMC6446283 DOI: 10.1186/s12880-019-0324-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Accepted: 03/11/2019] [Indexed: 02/04/2023] Open
Abstract
Background Initial reports of 23Na magnetic resonance imaging (MRI) date back to the 1970s. However, methodological challenges of the technique hampered its widespread adoption for many years. Recent technical developments have overcome some of these limitations and have led to more optimal conditions for 23Na-MR imaging. In order to serve as a reliable tool for the assessment of clinical stroke or brain tumor patients, we investigated the repeatability and reproducibility of cerebral sodium (23Na) imaging in healthy subjects. Methods In this prospective, IRB approved study 12 consecutive healthy volunteers (8 female, age 31 ± 8.3) underwent three cerebral 23Na-MRI examinations at 3.0 T (TimTrio, Siemens Healthineers) distributed between two separate visits with an 8 day interval. For each scan a T1w MP-RAGE sequence for anatomical referencing and a 3D-density-adapted, radial GRE-sequence for 23Na-imaging were acquired using a dual-tuned (23Na/1H) head-coil. On 1 day, these scans were repeated consecutively; on the other day, the scans were performed once. 23Na-sequences were reconstructed according to the MP-RAGE sequence, allowing direct cross-referencing of ROIs. Circular ROIs were placed in predetermined anatomic regions: gray and white matter (GM, WM), head of the caudate nucleus (HCN), pons, and cerebellum. External 23Na-reference phantoms were used to calculate the tissue sodium content. Results Excellent correlation was found between repeated measurements on the same day (r2 = 0.94), as well as on a different day (r2 = 0.86). No significant differences were found based on laterality other than in the HCN (63.1 vs. 58.7 mmol/kg WW on the right (p = 0.01)). Pronounced inter-individual differences were identified in all anatomic regions. Moderate to good correlation (0.310 to 0.701) was found between the readers. Conclusion Our study has shown that intra-individual 23Na-concentrations in healthy subjects do not significantly differ after repeated scans on the same day and a pre-set time interval. This confirms the repeatability and reproducibility of cerebral 23Na-imaging. However, with manual ROI placement in predetermined anatomic landmarks, fluctuations in 23Na-concentrations can be observed.
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Affiliation(s)
- Melissa M Meyer
- Institute of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany.
| | - Stefan Haneder
- Institute of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany.,Institute of Diagnostic and Interventional Radiology, University Hospital Cologne, University of Cologne, Cologne, Germany
| | | | - Johannes Budjan
- Institute of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany
| | - John N Morelli
- St. John's Medical Center, 1923 South Utica Ave, Tulsa, OK, 74104, USA
| | - Lothar R Schad
- Department of Computer Assisted Clinical Medicine, Heidelberg University, Mannheim, Germany
| | - Hans U Kerl
- Department of Neuroradiology, University Medical Center Mannheim, Heidelberg University, Mannheim, Germany
| | - Stefan O Schoenberg
- Institute of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany
| | - Christoph Kabbasch
- Institute of Diagnostic and Interventional Radiology, University Hospital Cologne, University of Cologne, Cologne, Germany
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23
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Lott J, Platt T, Niesporek SC, Paech D, G. R. Behl N, Niendorf T, Bachert P, Ladd ME, Nagel AM. Corrections of myocardial tissue sodium concentration measurements in human cardiac
23
Na MRI at 7 Tesla. Magn Reson Med 2019; 82:159-173. [DOI: 10.1002/mrm.27703] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 01/25/2019] [Accepted: 01/31/2019] [Indexed: 12/24/2022]
Affiliation(s)
- Johanna Lott
- German Cancer Research Center (DKFZ), Medical Physics in Radiology Heidelberg Germany
- University of Heidelberg, Faculty of Physics and Astronomy Heidelberg Germany
| | - Tanja Platt
- German Cancer Research Center (DKFZ), Medical Physics in Radiology Heidelberg Germany
| | | | - Daniel Paech
- German Cancer Research Center (DKFZ) Radiology, Heidelberg Germany
| | - Nicolas G. R. Behl
- German Cancer Research Center (DKFZ), Medical Physics in Radiology Heidelberg Germany
| | - Thoralf Niendorf
- Max Delbrueck Center for Molecular Medicine in the Helmholtz Association Berlin Germany
- MRI. TOOLS GmbH Berlin Germany
| | - Peter Bachert
- German Cancer Research Center (DKFZ), Medical Physics in Radiology Heidelberg Germany
- University of Heidelberg, Faculty of Physics and Astronomy Heidelberg Germany
| | - Mark E. Ladd
- German Cancer Research Center (DKFZ), Medical Physics in Radiology Heidelberg Germany
- University of Heidelberg, Faculty of Physics and Astronomy Heidelberg Germany
- University of Heidelberg Faculty of Medicine Heidelberg Germany
| | - Armin M. Nagel
- German Cancer Research Center (DKFZ), Medical Physics in Radiology Heidelberg Germany
- Friedrich‐Alexander‐Universität Erlangen‐Nürnberg (FAU), University Hospital Erlangen Institute of Radiology Erlangen Germany
- Friedrich‐Alexander‐Universität Erlangen‐Nürnberg (FAU) Institute of Medical Physics Erlangen Germany
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24
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Huhn K, Engelhorn T, Linker RA, Nagel AM. Potential of Sodium MRI as a Biomarker for Neurodegeneration and Neuroinflammation in Multiple Sclerosis. Front Neurol 2019; 10:84. [PMID: 30804885 PMCID: PMC6378293 DOI: 10.3389/fneur.2019.00084] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 01/22/2019] [Indexed: 01/18/2023] Open
Abstract
In multiple sclerosis (MS), experimental and ex vivo studies indicate that pathologic intra- and extracellular sodium accumulation may play a pivotal role in inflammatory as well as neurodegenerative processes. Yet, in vivo assessment of sodium in the microenvironment is hard to achieve. Here, sodium magnetic resonance imaging (23NaMRI) with its non-invasive properties offers a unique opportunity to further elucidate the effects of sodium disequilibrium in MS pathology in vivo in addition to regular proton based MRI. However, unfavorable physical properties and low in vivo concentrations of sodium ions resulting in low signal-to-noise-ratio (SNR) as well as low spatial resolution resulting in partial volume effects limited the application of 23NaMRI. With the recent advent of high-field MRI scanners and more sophisticated sodium MRI acquisition techniques enabling better resolution and higher SNR, 23NaMRI revived. These studies revealed pathologic total sodium concentrations in MS brains now even allowing for the (partial) differentiation of intra- and extracellular sodium accumulation. Within this review we (1) demonstrate the physical basis and imaging techniques of 23NaMRI and (2) analyze the present and future clinical application of 23NaMRI focusing on the field of MS thus highlighting its potential as biomarker for neuroinflammation and -degeneration.
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Affiliation(s)
- Konstantin Huhn
- Department of Neurology, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| | - Tobias Engelhorn
- Department of Neuroradiology, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany
| | - Ralf A Linker
- Department of Neurology, University of Regensburg, Regensburg, Germany
| | - Armin M Nagel
- Department of Radiology, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen, Germany.,Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
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25
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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: 321] [Impact Index Per Article: 45.9] [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.
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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.
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26
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Influence of Gadolinium-Based Contrast Agents on Tissue Sodium Quantification in Sodium Magnetic Resonance Imaging. Invest Radiol 2018; 53:555-562. [DOI: 10.1097/rli.0000000000000487] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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27
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Ridley B, Nagel AM, Bydder M, Maarouf A, Stellmann JP, Gherib S, Verneuil J, Viout P, Guye M, Ranjeva JP, Zaaraoui W. Distribution of brain sodium long and short relaxation times and concentrations: a multi-echo ultra-high field 23Na MRI study. Sci Rep 2018. [PMID: 29531255 PMCID: PMC5847519 DOI: 10.1038/s41598-018-22711-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Sodium (23Na) MRI proffers the possibility of novel information for neurological research but also particular challenges. Uncertainty can arise in in vivo 23Na estimates from signal losses given the rapidity of T2* decay due to biexponential relaxation with both short (T2*short) and long (T2*long) components. We build on previous work by characterising the decay curve directly via multi-echo imaging at 7 T in 13 controls with the requisite number, distribution and range to assess the distribution of both in vivo T2*short and T2*long and in variation between grey and white matter, and subregions. By modelling the relationship between signal and reference concentration and applying it to in vivo 23Na-MRI signal, 23Na concentrations and apparent transverse relaxation times of different brain regions were measured for the first time. Relaxation components and concentrations differed substantially between regions of differing tissue composition, suggesting sensitivity of multi-echo 23Na-MRI toward features of tissue composition. As such, these results raise the prospect of multi-echo 23Na-MRI as an adjunct source of information on biochemical mechanisms in both physiological and pathophysiological states.
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Affiliation(s)
- Ben Ridley
- Aix-Marseille Univ, CNRS, CRMBM UMR 7339, Marseille, France. .,APHM, Hôpitaux de la Timone, CEMEREM, Marseille, France.
| | - Armin M Nagel
- University Hospital Erlangen, Institute of Radiology, Erlangen, Germany.,Division of Medical Physics in Radiology, German Cancer Research Centre (DKFZ), Heidelberg, Germany
| | - Mark Bydder
- Aix-Marseille Univ, CNRS, CRMBM UMR 7339, Marseille, France.,APHM, Hôpitaux de la Timone, CEMEREM, Marseille, France
| | - Adil Maarouf
- Aix-Marseille Univ, CNRS, CRMBM UMR 7339, Marseille, France.,APHM, Hôpitaux de la Timone, CEMEREM, Marseille, France
| | - Jan-Patrick Stellmann
- Aix-Marseille Univ, CNRS, CRMBM UMR 7339, Marseille, France.,APHM, Hôpitaux de la Timone, CEMEREM, Marseille, France
| | - Soraya Gherib
- Aix-Marseille Univ, CNRS, CRMBM UMR 7339, Marseille, France.,APHM, Hôpitaux de la Timone, CEMEREM, Marseille, France
| | - Jeremy Verneuil
- Aix-Marseille Univ, CNRS, CRMBM UMR 7339, Marseille, France.,APHM, Hôpitaux de la Timone, CEMEREM, Marseille, France
| | - Patrick Viout
- Aix-Marseille Univ, CNRS, CRMBM UMR 7339, Marseille, France.,APHM, Hôpitaux de la Timone, CEMEREM, Marseille, France
| | - Maxime Guye
- Aix-Marseille Univ, CNRS, CRMBM UMR 7339, Marseille, France.,APHM, Hôpitaux de la Timone, CEMEREM, Marseille, France
| | - Jean-Philippe Ranjeva
- Aix-Marseille Univ, CNRS, CRMBM UMR 7339, Marseille, France.,APHM, Hôpitaux de la Timone, CEMEREM, Marseille, France
| | - Wafaa Zaaraoui
- Aix-Marseille Univ, CNRS, CRMBM UMR 7339, Marseille, France.,APHM, Hôpitaux de la Timone, CEMEREM, Marseille, France
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28
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Kopp C, Linz P, Maier C, Wabel P, Hammon M, Nagel AM, Rosenhauer D, Horn S, Uder M, Luft FC, Titze J, Dahlmann A. Elevated tissue sodium deposition in patients with type 2 diabetes on hemodialysis detected by 23Na magnetic resonance imaging. Kidney Int 2018; 93:1191-1197. [PMID: 29455909 DOI: 10.1016/j.kint.2017.11.021] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2017] [Revised: 11/09/2017] [Accepted: 11/16/2017] [Indexed: 12/25/2022]
Abstract
Long-term elevated blood sugar levels result in tissue matrix compositional changes in patients with diabetes mellitus type 2 (T2DM). We hypothesized that hemodialysis patients with T2DM might accumulate more tissue sodium than control hemodialysis patients. To test this, 23Na magnetic resonance imaging (23Na MRI) was used to estimate sodium in skin and muscle tissue in hemodialysis patients with or without T2DM. Muscle fat content was estimated by 1H MRI and tissue sodium content by 23Na MRI pre- and post-hemodialysis in ten hemodialysis patients with T2DM and in 30 matched control hemodialysis patients. We also assessed body fluid distribution with the Body Composition Monitor. 1H MRI indicated a tendency to higher muscle fat content in hemodialysis patients with T2DM compared to non-diabetic hemodialysis patients. 23Na MRI indicated increased sodium content in muscle and skin tissue of hemodialysis patients with T2DM compared to control hemodialysis patients. Multi-frequency bioimpedance was used to estimate extracellular water (ECW), and excess ECW in T2DM hemodialysis patients correlated with HbA1c levels. Sodium mobilization during hemodialysis lowered muscle sodium content post-dialysis to a greater degree in T2DM hemodialysis patients than in control hemodialysis patients. Thus, our findings provide evidence that increased sodium accumulation occurs in hemodialysis patients with T2DM and that impaired serum glucose metabolism is associated with disturbances in tissue sodium and water content.
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Affiliation(s)
- Christoph Kopp
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany.
| | - Peter Linz
- Institute of Radiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Carolin Maier
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Peter Wabel
- Fresenius Medical Care, Bad Homburg, Germany
| | - Matthias Hammon
- Institute of Radiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Armin M Nagel
- Institute of Radiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Daniela Rosenhauer
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | | | - Michael Uder
- Institute of Radiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Friedrich C Luft
- Experimental and Clinical Research Center, a joint cooperation between the Charité Medical Faculty and the Max-Delbrück Center for Molecular Medicine, Berlin, Germany; Department of Clinical Pharmacology, Vanderbilt University, Nashville, Tennessee, USA
| | - Jens Titze
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany; Department of Clinical Pharmacology, Vanderbilt University, Nashville, Tennessee, USA
| | - Anke Dahlmann
- Department of Nephrology and Hypertension, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
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29
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30
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Platt T, Umathum R, Fiedler TM, Nagel AM, Bitz AK, Maier F, Bachert P, Ladd ME, Wielpütz MO, Kauczor HU, Behl NG. In vivo self-gated 23
Na MRI at 7 T using an oval-shaped body resonator. Magn Reson Med 2018; 80:1005-1019. [DOI: 10.1002/mrm.27103] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 12/08/2017] [Accepted: 01/02/2018] [Indexed: 12/24/2022]
Affiliation(s)
- Tanja Platt
- Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280; 69120 Heidelberg Germany
| | - Reiner Umathum
- Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280; 69120 Heidelberg Germany
| | - Thomas M. Fiedler
- Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280; 69120 Heidelberg Germany
| | - Armin M. Nagel
- Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280; 69120 Heidelberg Germany
- Institute of Radiology; University Hospital Erlangen, Maximiliansplatz 3; 91054 Erlangen Germany
| | - Andreas K. Bitz
- Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280; 69120 Heidelberg Germany
- Faculty of Electrical Engineering and Information Technology; University of Applied Sciences Aachen, Eupener Str. 70; 52066 Aachen Germany
| | - Florian Maier
- Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280; 69120 Heidelberg Germany
| | - Peter Bachert
- Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280; 69120 Heidelberg Germany
- Faculty of Physics and Astronomy; University of Heidelberg, Im Neuenheimer Feld 226; 69120 Heidelberg Germany
| | - Mark E. Ladd
- Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280; 69120 Heidelberg Germany
- Faculty of Physics and Astronomy; University of Heidelberg, Im Neuenheimer Feld 226; 69120 Heidelberg Germany
- Faculty of Medicine; University of Heidelberg, Im Neuenheimer Feld 672; 69120 Heidelberg Germany
| | - Mark O. Wielpütz
- Translational Lung Research Center (TLRC); University of Heidelberg, German Center for Lung Research (DZL), Im Neuenheimer Feld 430; 69120 Heidelberg Germany
- Department of Diagnostic and Interventional Radiology; University Hospital of Heidelberg, Im Neuenheimer Feld 110; 69120 Heidelberg Germany
- Department of Diagnostic and Interventional Radiology with Nuclear Medicine; Thoraxklinik at University of Heidelberg, Röntgenstr. 1; 69126 Heidelberg Germany
| | - Hans-Ulrich Kauczor
- Translational Lung Research Center (TLRC); University of Heidelberg, German Center for Lung Research (DZL), Im Neuenheimer Feld 430; 69120 Heidelberg Germany
- Department of Diagnostic and Interventional Radiology; University Hospital of Heidelberg, Im Neuenheimer Feld 110; 69120 Heidelberg Germany
- Department of Diagnostic and Interventional Radiology with Nuclear Medicine; Thoraxklinik at University of Heidelberg, Röntgenstr. 1; 69126 Heidelberg Germany
| | - Nicolas G.R. Behl
- Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280; 69120 Heidelberg Germany
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31
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Lommen JM, Flassbeck S, Behl NG, Niesporek S, Bachert P, Ladd ME, Nagel AM. Probing the microscopic environment of 23
Na ions in brain tissue by MRI: On the accuracy of different sampling schemes for the determination of rapid, biexponential T2* decay at low signal-to-noise ratio. Magn Reson Med 2018; 80:571-584. [DOI: 10.1002/mrm.27059] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 11/21/2017] [Accepted: 12/05/2017] [Indexed: 01/28/2023]
Affiliation(s)
- Jonathan M. Lommen
- Medical Physics in Radiology, German Cancer Research Center (DKFZ); Heidelberg Germany
| | - Sebastian Flassbeck
- Medical Physics in Radiology, German Cancer Research Center (DKFZ); Heidelberg Germany
| | - Nicolas G.R. Behl
- Medical Physics in Radiology, German Cancer Research Center (DKFZ); Heidelberg Germany
| | - Sebastian Niesporek
- Medical Physics in Radiology, German Cancer Research Center (DKFZ); Heidelberg Germany
| | - Peter Bachert
- Medical Physics in Radiology, German Cancer Research Center (DKFZ); Heidelberg Germany
- University of Heidelberg, Faculty of Physics and Astronomy; Heidelberg Germany
| | - Mark E. Ladd
- Medical Physics in Radiology, German Cancer Research Center (DKFZ); Heidelberg Germany
- University of Heidelberg, Faculty of Physics and Astronomy; Heidelberg Germany
- University of Heidelberg, Faculty of Medicine; Heidelberg Germany
| | - Armin M. Nagel
- Medical Physics in Radiology, German Cancer Research Center (DKFZ); Heidelberg Germany
- Institute of Radiology; University Hospital Erlangen; Erlangen Germany
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32
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Karg MV, Bosch A, Kannenkeril D, Striepe K, Ott C, Schneider MP, Boemke-Zelch F, Linz P, Nagel AM, Titze J, Uder M, Schmieder RE. SGLT-2-inhibition with dapagliflozin reduces tissue sodium content: a randomised controlled trial. Cardiovasc Diabetol 2018; 17:5. [PMID: 29301520 PMCID: PMC5753452 DOI: 10.1186/s12933-017-0654-z] [Citation(s) in RCA: 137] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 12/26/2017] [Indexed: 12/11/2022] Open
Abstract
Background and aims Sodium tissue content by 23Na magnetic resonance imaging (Na-MRI) has been validated in experimental and human studies. SGLT-2 inhibition blocks the reabsorption of glucose and of sodium in the proximal tubular cells in a 1:1 fashion. We hypothesized that SGLT-2 inhibition in patients with type 2 diabetes characterized by sodium retention leads to decreased tissue sodium content due to its pharmacological action. Materials and methods In a prospective double blind, placebo controlled, cross-over trial 59 patients (61 ± 7.6 years) with type 2 diabetes were randomized to either dapagliflozin 10 mg or placebo once daily for 6 weeks each. In addition to metabolic parameters and ambulatory blood pressure (BP) we analysed the sodium content in the skin and muscles of the lower leg by Na-MRI. Results Compared to baseline 6 weeks treatment with the SGLT-2 inhibitor dapagliflozin decreased fasting (132 ± 28 vs. 114 ± 19 mg/dl, p < 0.001), postprandial blood glucose (178 ± 66 mg/dl vs. 153 ± 46 mg/dl, p < 0.001), body weight (87.6 vs. 86.6 kg, p < 0.001) and systolic (129 ± 12 vs. 126 ± 11 mmHg, p = 0.010), and diastolic (77.4 ± 9 vs. 75.6 ± 8 mmHg, p = 0.024), 24-h ambulatory BP. Tissue sodium content in the skin was reduced after 6 weeks treatment with dapagliflozin compared to baseline [24.1 ± 6.6 vs. 22.7 ± 6.4 A.U.(arbitrary unit) p = 0.013]. No significant reduction of tissue sodium content was observed in the muscle (M. triceps surae: 20.5 ± 3.5 vs. 20.4 ± 3.7 A.U. p = 0.801). No clear significant difference in tissue water content of muscle and skin was observed after 6 weeks of treatment with dapagliflozin, compared to baseline. Conclusion SGLT-2 inhibition with dapagliflozin resulted in a significant decrease in tissue sodium content of the skin after 6 weeks. This observation point to a decrease of total sodium content in patients with type 2 diabetes prone to cardiovascular complications, that might be mitigated by SGLT-2 inhibition. Trial registration The study was registered at http://www.clinicaltrials.gov (NCT02383238) retrospectively registered
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Affiliation(s)
- M V Karg
- Department of Nephrology and Hypertension, University Hospital Erlangen, Ulmenweg 18, 91054, Erlangen, Germany
| | - A Bosch
- Department of Nephrology and Hypertension, University Hospital Erlangen, Ulmenweg 18, 91054, Erlangen, Germany
| | - D Kannenkeril
- Department of Nephrology and Hypertension, University Hospital Erlangen, Ulmenweg 18, 91054, Erlangen, Germany
| | - K Striepe
- Department of Nephrology and Hypertension, University Hospital Erlangen, Ulmenweg 18, 91054, Erlangen, Germany
| | - C Ott
- Department of Nephrology and Hypertension, University Hospital Erlangen, Ulmenweg 18, 91054, Erlangen, Germany
| | - M P Schneider
- Department of Nephrology and Hypertension, University Hospital Erlangen, Ulmenweg 18, 91054, Erlangen, Germany
| | - F Boemke-Zelch
- Department of Nephrology and Hypertension, University Hospital Erlangen, Ulmenweg 18, 91054, Erlangen, Germany
| | - P Linz
- Department for Diagnostic Radiology, University Hospital Erlangen, Erlangen, Germany
| | - A M Nagel
- Department for Diagnostic Radiology, University Hospital Erlangen, Erlangen, Germany
| | - J Titze
- Department of Nephrology and Hypertension, University Hospital Erlangen, Ulmenweg 18, 91054, Erlangen, Germany.,Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - M Uder
- Department for Diagnostic Radiology, University Hospital Erlangen, Erlangen, Germany
| | - R E Schmieder
- Department of Nephrology and Hypertension, University Hospital Erlangen, Ulmenweg 18, 91054, Erlangen, Germany.
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33
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Improved
$$T_{2}^{*}$$
T
2
∗
determination in 23Na, 35Cl, and 17O MRI using iterative partial volume correction based on 1H MRI segmentation. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2017; 30:519-536. [DOI: 10.1007/s10334-017-0623-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 04/06/2017] [Accepted: 04/19/2017] [Indexed: 12/25/2022]
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34
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Gerlach DA, Schopen K, Linz P, Johannes B, Titze J, Zange J, Rittweger J. Atrophy of calf muscles by unloading results in an increase of tissue sodium concentration and fat fraction decrease: a 23Na MRI physiology study. Eur J Appl Physiol 2017; 117:1585-1595. [DOI: 10.1007/s00421-017-3647-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 05/17/2017] [Indexed: 01/27/2023]
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35
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Iterative reconstruction of radially-sampled 31 P bSSFP data using prior information from 1 H MRI. Magn Reson Imaging 2017; 37:147-158. [DOI: 10.1016/j.mri.2016.11.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Revised: 10/10/2016] [Accepted: 11/17/2016] [Indexed: 12/18/2022]
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36
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Nimerovsky E, Ilott AJ, Jerschow A. Low-power suppression of fast-motion spin 3/2 signals. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 272:129-140. [PMID: 27689532 DOI: 10.1016/j.jmr.2016.09.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 09/11/2016] [Accepted: 09/14/2016] [Indexed: 06/06/2023]
Abstract
Triple Quantum Filters (TQFs) are frequently used for the selection of bi-exponentially relaxing spin 3/2 nuclei (in particular 23Na) in ordered environments, such as biological tissues. These methods provide an excellent selection of slow-motion spins, but their sensitivity is generally low, and coherence selection requirements may lead to long experiments when applied in vivo. Alternative methods, such as 2P DIM, have demonstrated that the sensitivities of the signals from bi-exponentially relaxing sodium can be significantly increased using strategies other than TQFs. A shortcoming of the 2P DIM method is its strong dependence on B0 inhomogeneities. We describe here a method, which is sensitive to the slow-motion regime, while the signal from spins in the fast-motion regime is suppressed. This method is shown to be more effective than TQFs, requires minimal phase cycling for the suppression of the influence of rf inhomogeneity, and has less dependence on resonance offsets and B0-inhomogeneity than 2P DIM.
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Affiliation(s)
- Evgeny Nimerovsky
- Department of Chemistry, New York University, New York, NY 10003, USA
| | - Andrew J Ilott
- Department of Chemistry, New York University, New York, NY 10003, USA
| | - Alexej Jerschow
- Department of Chemistry, New York University, New York, NY 10003, USA.
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37
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Ludwig U, Eisenbeiss AK, Scheifele C, Nelson K, Bock M, Hennig J, von Elverfeldt D, Herdt O, Flügge T, Hövener JB. Dental MRI using wireless intraoral coils. Sci Rep 2016; 6:23301. [PMID: 27021387 PMCID: PMC4810435 DOI: 10.1038/srep23301] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 03/03/2016] [Indexed: 11/09/2022] Open
Abstract
Currently, the gold standard for dental imaging is projection radiography or cone-beam computed tomography (CBCT). These methods are fast and cost-efficient, but exhibit poor soft tissue contrast and expose the patient to ionizing radiation (X-rays). The need for an alternative imaging modality e.g. for soft tissue management has stimulated a rising interest in dental magnetic resonance imaging (MRI) which provides superior soft tissue contrast. Compared to X-ray imaging, however, so far the spatial resolution of MRI is lower and the scan time is longer. In this contribution, we describe wireless, inductively-coupled intraoral coils whose local sensitivity enables high resolution MRI of dental soft tissue. In comparison to CBCT, a similar image quality with complementary contrast was obtained ex vivo. In-vivo, a voxel size of the order of 250 ∙ 250 ∙ 500 μm(3) was achieved in 4 min only. Compared to dental MRI acquired with clinical equipment, the quality of the images was superior in the sensitive volume of the coils and is expected to improve the planning of interventions and monitoring thereafter. This method may enable a more accurate dental diagnosis and avoid unnecessary interventions, improving patient welfare and bringing MRI a step closer to becoming a radiation-free alternative for dental imaging.
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Affiliation(s)
- Ute Ludwig
- Medical Physics, Department of Radiology, University Medical Center Freiburg, Freiburg, Germany
| | - Anne-Katrin Eisenbeiss
- Medical Physics, Department of Radiology, University Medical Center Freiburg, Freiburg, Germany
- Division of Oral and Maxillofacial Surgery, University Medical Center Freiburg, Freiburg, Germany
| | - Christian Scheifele
- Division of Oral and Maxillofacial Surgery, University Medical Center Freiburg, Freiburg, Germany
| | - Katja Nelson
- Division of Oral and Maxillofacial Surgery, University Medical Center Freiburg, Freiburg, Germany
| | - Michael Bock
- Medical Physics, Department of Radiology, University Medical Center Freiburg, Freiburg, Germany
| | - Jürgen Hennig
- Medical Physics, Department of Radiology, University Medical Center Freiburg, Freiburg, Germany
| | - Dominik von Elverfeldt
- Medical Physics, Department of Radiology, University Medical Center Freiburg, Freiburg, Germany
| | - Olga Herdt
- Medical Physics, Department of Radiology, University Medical Center Freiburg, Freiburg, Germany
| | - Tabea Flügge
- Division of Oral and Maxillofacial Surgery, University Medical Center Freiburg, Freiburg, Germany
| | - Jan-Bernd Hövener
- Medical Physics, Department of Radiology, University Medical Center Freiburg, Freiburg, Germany
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38
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Zöllner FG, Konstandin S, Lommen J, Budjan J, Schoenberg SO, Schad LR, Haneder S. Quantitative sodium MRI of kidney. NMR IN BIOMEDICINE 2016; 29:197-205. [PMID: 25728879 DOI: 10.1002/nbm.3274] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Revised: 01/13/2015] [Accepted: 01/25/2015] [Indexed: 05/25/2023]
Abstract
One of the main tasks of the human kidneys is to maintain the homeostasis of the body's fluid and electrolyte balance by filtration of the plasma and excretion of the end products. Herein, the regulation of extracellular sodium in the kidney is of particular importance. Sodium MRI ((23)Na MRI) allows for the absolute quantification of the tissue sodium concentration (TSC) and thereby provides a direct link between TSC and tissue viability. Renal (23)Na MRI can provide new insights into physiological tissue function and viability thought to differ from the information obtained by standard (1)H MRI. Sodium imaging has the potential to become an independent surrogate biomarker not only for renal imaging, but also for oncology indications. However, this technique is now on the threshold of clinical implementation. Numerous, initial pre-clinical and clinical studies have already outlined the potential of this technique; however, future studies need to be extended to larger patient groups to show the diagnostic outcome. In conclusion, (23)Na MRI is seen as a powerful technique with the option to establish a non-invasive renal biomarker for tissue viability, but is still a long way from real clinical implementation.
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Affiliation(s)
- Frank G Zöllner
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Simon Konstandin
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- MR-Imaging and Spectroscopy, Faculty 01 (Physics/Electrical Engineering), University of Bremen, Bremen, Germany
| | - Jonathan Lommen
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Johannes Budjan
- Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Stefan O Schoenberg
- Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Lothar R Schad
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Stefan Haneder
- Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- Department of Radiology, University Hospital of Cologne, Cologne, Germany
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39
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Shah NJ, Worthoff WA, Langen KJ. Imaging of sodium in the brain: a brief review. NMR IN BIOMEDICINE 2016; 29:162-174. [PMID: 26451752 DOI: 10.1002/nbm.3389] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 07/30/2015] [Accepted: 08/07/2015] [Indexed: 06/05/2023]
Abstract
Sodium-based MRI plays a vital role in the study of metabolism and can unveil valuable information about emerging and existing pathology--in particular in the human brain. Sodium is the second most abundant MR active nucleus in living tissue and, due to its quadrupolar nature, has magnetic properties not common to conventional proton MRI, which can reveal further insights, such as information on the compartmental distribution of intra- and extracellular sodium. Nevertheless, the use of sodium nuclei for imaging comes at the expense of a lower sensitivity and significantly reduced relaxation times, making in vivo sodium studies feasible only at high magnetic field strength and by the use of dedicated pulse sequences. Hybrid imaging combining sodium MRI and positron emission tomography (PET) simultaneously is a novel and promising approach to access information on dynamic metabolism with much increased, PET-derived specificity. Application of this new methodology is demonstrated herein using examples from tumour imaging.
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Affiliation(s)
- N Jon Shah
- Institute of Neuroscience and Medicine-4, Forschungszentrum Juelich GmbH, 52425, Jülich, Germany
- Department of Neurology, Faculty of Medicine, RWTH Aachen University, Aachen, Germany
- Jülich Aachen Research Alliance (JARA) - Translational Brain Medicine, Aachen and Jülich, Germany
| | - Wieland A Worthoff
- Institute of Neuroscience and Medicine-4, Forschungszentrum Juelich GmbH, 52425, Jülich, Germany
| | - Karl-Josef Langen
- Institute of Neuroscience and Medicine-4, Forschungszentrum Juelich GmbH, 52425, Jülich, Germany
- Jülich Aachen Research Alliance (JARA) - Translational Brain Medicine, Aachen and Jülich, Germany
- Department of Nuclear Medicine, Faculty of Medicine, RWTH Aachen University, Aachen, Germany
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40
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[Functional MRI 2.0. ²³Na and CEST imaging]. Radiologe 2016; 56:159-69. [PMID: 26796336 DOI: 10.1007/s00117-015-0071-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
In recent years the purely morphological magnetic resonance imaging (MRI) has been increasingly flanked by so-called functional imaging methods, such as diffusion-weighted imaging (DWI), to obtain additional information about tissue or pathological processes. This review article presents two MR techniques that can detect physiological processes in the human body. In contrast to all other functional MR imaging techniques, which are based on hydrogen protons, the first technique presented (X-nuclei imaging) uses the spin of other nuclei for imaging and consequently allows a completely different insight into the human body. In this article X-nuclei imaging is focused on sodium ((23)Na) MRI because it currently represents the main focus of research in this field due to the favorable MR properties of sodium. The second MR technique presented is the relatively novel chemical exchange saturation transfer (CEST) imaging that can detect exchange processes between protons in metabolites and protons in free water. The first part of this article introduces the basic technical principles, problems, advantages and disadvantages of these two MR techniques, whereas the second part highlights the potential clinical applications. Examples illustrate several potential applications in neuroimaging (e. g. stroke and tumors), musculoskeletal imaging (e. g. osteoarthritis and degenerative processes) and abdominal imaging (e. g. kidneys and hypertension). Both techniques inherently contain an incredible potential for future imaging but are still on the threshold of clinical use and are currently under evaluation in many university centers.
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41
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Retrospectively-gated CINE 23Na imaging of the heart at 7.0 Tesla using density-adapted 3D projection reconstruction. Magn Reson Imaging 2015; 33:1091-1097. [DOI: 10.1016/j.mri.2015.06.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 05/28/2015] [Accepted: 06/20/2015] [Indexed: 11/21/2022]
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42
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Lee KC, Yu JF, Lee YS, Huang GJ, Chan HL, Lin IT, Chen JH. In Vivo Sodium MRI for Mouse Model of Ischemic Stroke at 7 T: Preliminary Results. J Med Biol Eng 2015. [DOI: 10.1007/s40846-015-0072-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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43
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Graessl A, Ruehle A, Waiczies H, Resetar A, Hoffmann SH, Rieger J, Wetterling F, Winter L, Nagel AM, Niendorf T. Sodium MRI of the human heart at 7.0 T: preliminary results. NMR IN BIOMEDICINE 2015; 28:967-975. [PMID: 26082025 DOI: 10.1002/nbm.3338] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 05/10/2015] [Accepted: 05/12/2015] [Indexed: 06/04/2023]
Abstract
The objective of this work was to examine the feasibility of three-dimensional (3D) and whole heart coverage (23)Na cardiac MRI at 7.0 T including single-cardiac-phase and cinematic (cine) regimes. A four-channel transceiver RF coil array tailored for (23)Na MRI of the heart at 7.0 T (f = 78.5 MHz) is proposed. An integrated bow-tie antenna building block is used for (1)H MR to support shimming, localization and planning in a clinical workflow. Signal absorption rate simulations and assessment of RF power deposition were performed to meet the RF safety requirements. (23) Na cardiac MR was conducted in an in vivo feasibility study. 3D gradient echo (GRE) imaging in conjunction with Cartesian phase encoding (total acquisition time T(AQ) = 6 min 16 s) and whole heart coverage imaging employing a density-adapted 3D radial acquisition technique (T(AQ) = 18 min 20 s) were used. For 3D GRE-based (23)Na MRI, acquisition of standard views of the heart using a nominal in-plane resolution of (5.0 × 5.0) mm(2) and a slice thickness of 15 mm were feasible. For whole heart coverage 3D density-adapted radial (23)Na acquisitions a nominal isotropic spatial resolution of 6 mm was accomplished. This improvement versus 3D conventional GRE acquisitions reduced partial volume effects along the slice direction and enabled retrospective image reconstruction of standard or arbitrary views of the heart. Sodium cine imaging capabilities were achieved with the proposed RF coil configuration in conjunction with 3D radial acquisitions and cardiac gating. Cardiac-gated reconstruction provided an enhancement in blood-myocardium contrast of 20% versus the same data reconstructed without cardiac gating. The proposed transceiver array enables (23)Na MR of the human heart at 7.0 T within clinical acceptable scan times. This capability is in positive alignment with the needs of explorations that are designed to examine the potential of (23)Na MRI for the assessment of cardiovascular and metabolic diseases.
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Affiliation(s)
- Andreas Graessl
- Berlin Ultrahigh Field Facility (BUFF), Max-Delbrueck-Center for Molecular Medicine, Berlin, Germany
| | - Anjuli Ruehle
- Berlin Ultrahigh Field Facility (BUFF), Max-Delbrueck-Center for Molecular Medicine, Berlin, Germany
| | | | - Ana Resetar
- Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Stefan H Hoffmann
- Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | | | | | - Lukas Winter
- Berlin Ultrahigh Field Facility (BUFF), Max-Delbrueck-Center for Molecular Medicine, Berlin, Germany
| | - Armin M Nagel
- Division of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Thoralf Niendorf
- Berlin Ultrahigh Field Facility (BUFF), Max-Delbrueck-Center for Molecular Medicine, Berlin, Germany
- Experimental and Clinical Research Center, a joint cooperation between the Charité Medical Faculty and the Max-Delbrück Center for Molecular Medicine, Berlin, Germany
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44
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Behl NG, Gnahm C, Bachert P, Ladd ME, Nagel AM. Three-dimensional dictionary-learning reconstruction of 23
Na MRI data. Magn Reson Med 2015; 75:1605-16. [DOI: 10.1002/mrm.25759] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 04/02/2015] [Accepted: 04/13/2015] [Indexed: 12/26/2022]
Affiliation(s)
- Nicolas G.R. Behl
- Department of Medical Physics in Radiology; German Cancer Research Center (DKFZ); Heidelberg Germany
| | - Christine Gnahm
- Department of Medical Physics in Radiology; German Cancer Research Center (DKFZ); Heidelberg Germany
| | - Peter Bachert
- Department of Medical Physics in Radiology; German Cancer Research Center (DKFZ); Heidelberg Germany
| | - Mark E. Ladd
- Department of Medical Physics in Radiology; German Cancer Research Center (DKFZ); Heidelberg Germany
| | - Armin M. Nagel
- Department of Medical Physics in Radiology; German Cancer Research Center (DKFZ); Heidelberg Germany
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45
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Niesporek SC, Hoffmann SH, Berger MC, Benkhedah N, Kujawa A, Bachert P, Nagel AM. Partial volume correction for in vivo 23 Na-MRI data of the human brain. Neuroimage 2015; 112:353-363. [DOI: 10.1016/j.neuroimage.2015.03.025] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 02/02/2015] [Accepted: 03/11/2015] [Indexed: 12/16/2022] Open
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46
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Malzacher M, Kalayciyan R, Konstandin S, Haneder S, Schad LR. Sodium-23 MRI of whole spine at 3 Tesla using a 5-channel receive-only phased-array and a whole-body transmit resonator. Z Med Phys 2015; 26:95-100. [PMID: 25891846 DOI: 10.1016/j.zemedi.2015.03.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 03/12/2015] [Accepted: 03/24/2015] [Indexed: 12/15/2022]
Abstract
Sodium magnetic resonance imaging ((23)Na MRI) is a unique and non-invasive imaging technique which provides important information on cellular level about the tissue of the human body. Several applications for (23)Na MRI were investigated with regard to the examination of the tissue viability and functionality for example in the brain, the heart or the breast. The (23)Na MRI technique can also be integrated as a potential monitoring instrument after radiotherapy or chemotherapy. The main contribution in this work was the adaptation of (23)Na MRI for spine imaging, which can provide essential information on the integrity of the intervertebral disks with respect to the early detection of disk degeneration. In this work, a transmit-only receive-only dual resonator system was designed and developed to cover the whole human spine using (23)Na MRI and increase the receive sensitivity. The resonator system consisted of an already presented (23)Na whole-body resonator and a newly developed 5-channel receive-only phased-array. The resonator system was first validated using bench top and phantom measurements. A threefold SNR improvement at the depth of the spine (∼7cm) over the whole-body resonator was achieved using the spine array. (23)Na MR measurements of the human spine using the transmit-only receive-only resonator system were performed on a healthy volunteer within an acquisition time of 10minutes. A density adapted 3D radial sequence was chosen with 6mm isotropic resolution, 49ms repetition time and a short echo time of 540μs. Furthermore, it was possible to quantify the tissue sodium concentration in the intervertebral discs in the lumbar region (120ms repetition time) using this setup.
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Affiliation(s)
- Matthias Malzacher
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim, Germany.
| | - Raffi Kalayciyan
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim, Germany
| | - Simon Konstandin
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim, Germany
| | - Stefan Haneder
- Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim, Germany; Department of Radiology, University Hospital of Cologne, Kerpener Str. 62, D-50937 Köln, Germany
| | - Lothar R Schad
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim, Germany
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47
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Benkhedah N, Hoffmann SH, Biller A, Nagel AM. Evaluation of adaptive combination of 30‐channel head receive coil array data in
23
N
a
MR
imaging. Magn Reson Med 2015; 75:527-36. [DOI: 10.1002/mrm.25572] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 10/16/2014] [Accepted: 11/17/2014] [Indexed: 11/09/2022]
Affiliation(s)
- Nadia Benkhedah
- German Cancer Research Center (DKFZ), Division of Medical Physics in Radiology Heidelberg Germany
| | - Stefan H. Hoffmann
- German Cancer Research Center (DKFZ), Division of Medical Physics in Radiology Heidelberg Germany
| | - Armin Biller
- University Hospital Heidelberg, Department of Neuroradiology Heidelberg Germany
| | - Armin M. Nagel
- German Cancer Research Center (DKFZ), Division of Medical Physics in Radiology Heidelberg Germany
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48
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Wetterling F, Gallagher L, Mullin J, Holmes WM, McCabe C, Macrae IM, Fagan AJ. Sodium-23 magnetic resonance imaging has potential for improving penumbra detection but not for estimating stroke onset time. J Cereb Blood Flow Metab 2015; 35:103-10. [PMID: 25335803 PMCID: PMC4294399 DOI: 10.1038/jcbfm.2014.174] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 08/18/2014] [Accepted: 09/17/2014] [Indexed: 02/06/2023]
Abstract
Tissue sodium concentration increases in irreversibly damaged (core) tissue following ischemic stroke and can potentially help to differentiate the core from the adjacent hypoperfused but viable penumbra. To test this, multinuclear hydrogen-1/sodium-23 magnetic resonance imaging (MRI) was used to measure the changing sodium signal and hydrogen-apparent diffusion coefficient (ADC) in the ischemic core and penumbra after rat middle cerebral artery occlusion (MCAO). Penumbra and core were defined from perfusion imaging and histologically defined irreversibly damaged tissue. The sodium signal in the core increased linearly with time, whereas the ADC rapidly decreased by >30% within 20 minutes of stroke onset, with very little change thereafter (0.5-6 hours after MCAO). Previous reports suggest that the time point at which tissue sodium signal starts to rise above normal (onset of elevated tissue sodium, OETS) represents stroke onset time (SOT). However, extrapolating core data back in time resulted in a delay of 72 ± 24 minutes in OETS compared with actual SOT. At the OETS in the core, penumbra sodium signal was significantly decreased (88 ± 6%, P=0.0008), whereas penumbra ADC was not significantly different (92 ± 18%, P=0.2) from contralateral tissue. In conclusion, reduced sodium-MRI signal may serve as a viability marker for penumbra detection and can complement hydrogen ADC and perfusion MRI in the time-independent assessment of tissue fate in acute stroke patients.
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Affiliation(s)
- Friedrich Wetterling
- Department of Psychiatry, School of Medicine, Trinity College, The University of Dublin, College Green, Dublin, Ireland
| | - Lindsay Gallagher
- Glasgow Experimental MRI Centre, Institute of Neuroscience and Psychology, College of Medicine, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Jim Mullin
- Glasgow Experimental MRI Centre, Institute of Neuroscience and Psychology, College of Medicine, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - William M Holmes
- Glasgow Experimental MRI Centre, Institute of Neuroscience and Psychology, College of Medicine, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Chris McCabe
- Glasgow Experimental MRI Centre, Institute of Neuroscience and Psychology, College of Medicine, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - I Mhairi Macrae
- Glasgow Experimental MRI Centre, Institute of Neuroscience and Psychology, College of Medicine, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Andrew J Fagan
- Centre for Advanced Medical Imaging, St James's Hospital/Trinity College Dublin, Dublin, Ireland
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49
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Linz P, Santoro D, Renz W, Rieger J, Ruehle A, Ruff J, Deimling M, Rakova N, Muller DN, Luft FC, Titze J, Niendorf T. Skin sodium measured with ²³Na MRI at 7.0 T. NMR IN BIOMEDICINE 2015; 28:54-62. [PMID: 25328128 DOI: 10.1002/nbm.3224] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 09/10/2014] [Accepted: 09/10/2014] [Indexed: 06/04/2023]
Abstract
Skin sodium (Na(+) ) storage, as a physiologically important regulatory mechanism for blood pressure, volume regulation and, indeed, survival, has recently been rediscovered. This has prompted the development of MRI methods to assess Na(+) storage in humans ((23) Na MRI) at 3.0 T. This work examines the feasibility of high in-plane spatial resolution (23) Na MRI in skin at 7.0 T. A two-channel transceiver radiofrequency (RF) coil array tailored for skin MRI at 7.0 T (f = 78.5 MHz) is proposed. Specific absorption rate (SAR) simulations and a thorough assessment of RF power deposition were performed to meet the safety requirements. Human skin was examined in an in vivo feasibility study using two-dimensional gradient echo imaging. Normal male adult volunteers (n = 17; mean ± standard deviation, 46 ± 18 years; range, 20-79 years) were investigated. Transverse slices of the calf were imaged with (23) Na MRI using a high in-plane resolution of 0.9 × 0.9 mm(2) . Skin Na(+) content was determined using external agarose standards covering a physiological range of Na(+) concentrations. To assess the intra-subject reproducibility, each volunteer was examined three to five times with each session including a 5-min walk and repositioning/preparation of the subject. The age dependence of skin Na(+) content was investigated. The (23) Na RF coil provides improved sensitivity within a range of 1 cm from its surface versus a volume RF coil which facilitates high in-plane spatial resolution imaging of human skin. Intra-subject variability of human skin Na(+) content in the volunteer population was <10.3%. An age-dependent increase in skin Na(+) content was observed (r = 0.78). The assignment of Na(+) stores with (23) Na MRI techniques could be improved at 7.0 T compared with current 3.0 T technology. The benefits of such improvements may have the potential to aid basic research and clinical applications designed to unlock questions regarding the Na(+) balance and Na(+) storage function of skin.
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Affiliation(s)
- Peter Linz
- Interdisciplinary Center for Clinical Research, Nikolaus-Fiebiger-Center for Molecular Medicine, Friedrich-Alexander-University Erlangen-Nürnberg, Germany
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Konstandin S, Krämer P, Günther M, Schad LR. Sodium magnetic resonance imaging using ultra-short echo time sequences with anisotropic resolution and uniform k-space sampling. Magn Reson Imaging 2014; 33:319-27. [PMID: 25527394 DOI: 10.1016/j.mri.2014.12.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 12/01/2014] [Accepted: 12/01/2014] [Indexed: 01/12/2023]
Abstract
A method for uniform k-space sampling of 3D ultra-short echo time (UTE) techniques with anisotropic resolution in one direction is introduced to increase signal-to-noise ratio (SNR). State-of-the-art acquisition schemes for sodium MRI with radial (projection reconstruction) and twisting (twisted projection imaging (TPI)) trajectories are investigated regarding SNR efficiency, blurring behavior under T2(⁎) decay, and measurement time in case of anisotropic field-of-view and resolution. 3D radial and twisting trajectories are redistributed in k-space for UTE sodium MRI with homogeneous noise distribution and optimal SNR efficiency, if T2(⁎) decay can be neglected. Simulations based on Voronoi tessellations and phantom simulations/measurements were performed to calculate SNR efficiency. Point-spread functions were simulated to demonstrate the influence of T2(⁎) decay on SNR and resolution. Phantom simulations/measurements and in vivo measurements confirm the SNR gain obtained by simulations based on Voronoi cells. An increase in SNR of up to 21% at an anisotropy factor of 10 could be theoretically achieved by TPI with projection adaption compared to the same sequence but without redistribution of projections in k-space. Sodium MRI with anisotropic resolution and uniform k-space sampling is demonstrated by in vivo measurements of human intervertebral disks and heart at 3 T. The SNR gain can be invested in a measurement time reduction of up to 32%, which is important especially for sodium MRI.
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Affiliation(s)
- Simon Konstandin
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany; MR-Imaging and Spectroscopy, Faculty 01 (Physics/Electrical Engineering), University of Bremen, NW 1 Otto-Hahn-Allee 1, 28359 Bremen, Germany.
| | - Philipp Krämer
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany
| | - Matthias Günther
- MR-Imaging and Spectroscopy, Faculty 01 (Physics/Electrical Engineering), University of Bremen, NW 1 Otto-Hahn-Allee 1, 28359 Bremen, Germany; Fraunhofer MEVIS, Universitätsallee 29, 28359 Bremen, Germany
| | - Lothar R Schad
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany
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