Reproducibility of Glutamate, Glutathione, and GABA Measurements in vivo by Single-Voxel STEAM Magnetic Resonance Spectroscopy at 7-Tesla in Healthy Individuals

Abstract Background Single-voxel proton cardiovascular magnetic resonance spectroscopy (1H-CMRS) benefits from 3 T to detect metabolic abnormalities with the quantification of intramyocardial fatty acids (FA) and creatine (Cr). Conventional point resolved spectroscopy (PRESS) sequence remains the preferred choice for CMRS, despite its chemical shift displacement error (CSDE) at high field (≥ 3 T). Alternative candidate sequences are the semi-adiabatic Localization by Adiabatic SElective Refocusing (sLASER) recommended for brain and musculoskeletal applications and the localized stimulated echo acquisition mode (STEAM). In this study, we aim to compare these three single-voxel 1H-CMRS techniques: PRESS, sLASER and STEAM for reproducible quantification of myocardial FA and Cr at 3 T. Sequences are compared both using breath-hold (BH) and free-breathing (FB) acquisitions. Methods CMRS accuracy and theoretical CSDE were verified on a purposely-designed fat–water phantom. FA and Cr CMRS data quality and reliability were evaluated in the interventricular septum of 10 healthy subjects, comparing repeated BH and free-breathing with retrospective gating. Results Measured FA/W ratio deviated from expected phantom ratio due to CSDE with all sequences. sLASER supplied the lowest bias (10%, vs -28% and 27% for PRESS and STEAM). In vivo, PRESS provided the highest signal-to-noise ratio (SNR) in FB scans (27.5 for Cr and 103.2 for FA). Nevertheless, a linear regression analysis between the two BH showed a better correlation between myocardial Cr content measured with sLASER compared to PRESS (r = 0.46; p = 0.03 vs. r = 0.35; p = 0.07) and similar slopes of regression lines for FA measurements (r = 0.94; p < 0.001 vs. r = 0.87; p < 0.001). STEAM was unable to perform Cr measurement and was the method with the lowest correlation (r = 0.59; p = 0.07) for FA. No difference was found between measurements done either during BH or FB for Cr, FA and triglycerides using PRESS, sLASER and STEAM. Conclusion When quantifying myocardial lipids and creatine with CMR proton spectroscopy at 3 T, PRESS provided higher SNR, while sLASER was more reproducible both with single BH and FB scans.

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Current Practice and New Developments in the Use of In Vivo Magnetic Resonance Spectroscopy for the Assessment of Key Metabolites Implicated in the Pathophysiology of Schizophrenia

Current Topics in Medicinal Chemistry ◽

10.2174/1568026619666181130103559 ◽

2019 ◽

Vol 18 (21) ◽

pp. 1908-1924 ◽

Cited By ~ 2

Author(s):

Gerard E. Dwyer ◽

Kenneth Hugdahl ◽

Karsten Specht ◽

Renate Grüner

Keyword(s):

Magnetic Resonance ◽

Magnetic Resonance Spectroscopy ◽

Pulse Sequence ◽

Resonance Spectroscopy ◽

New Developments ◽

Single Voxel ◽

In Vivo Spectroscopy ◽

Pulse Sequence Design ◽

Review Current

Magnetic Resonance Spectroscopy (MRS) has become a valuable tool for investigating the biochemical bases of both normal processes in the healthy brain and elucidating the pathophysiology of neuropsychiatric disorders. As a rapidly advancing field, new developments in pulse sequence design have seen new possibilities arise in terms of what can be done with in vivo spectroscopy. While the applications of MRS are numerous, this review has been confined to the use of single voxel spectroscopy in the assessment of five key metabolites and their roles in schizophrenia: N-acetylaspartate (NAA), glutamate (Glu) and glutamine (Gln), γ-aminobutyric acid (GABA) and glutathione (GSH). This article will briefly cover the roles they play in schizophrenia, review current methods being used in their assessment and highlight new approaches that may potentially overcome some of the limitations current methods pose.

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Single voxel in vivo proton magnetic resonance spectroscopy of breast lesions: experience in 77 cases

Diagnostic and Interventional Radiology ◽

10.5152/dir.2012.005 ◽

2012 ◽

Author(s):

Isil Basara ◽

Sebnem Orguc ◽

Teoman Coskun

Keyword(s):

Magnetic Resonance ◽

Magnetic Resonance Spectroscopy ◽

Proton Magnetic Resonance ◽

Proton Magnetic Resonance Spectroscopy ◽

Resonance Spectroscopy ◽

Breast Lesions ◽

Single Voxel

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Cerebral phosphoester signals measured by 31P magnetic resonance spectroscopy at 3 and 7 Tesla

PLoS ONE ◽

10.1371/journal.pone.0248632 ◽

2021 ◽

Vol 16 (3) ◽

pp. e0248632

Author(s):

Shizhe Li ◽

Jan Willem van der Veen ◽

Li An ◽

JoEllyn Stolinski ◽

Christopher Johnson ◽

...

Keyword(s):

Magnetic Resonance ◽

Cell Membrane ◽

Magnetic Resonance Spectroscopy ◽

Building Blocks ◽

3 Tesla ◽

7 Tesla ◽

High Signal ◽

Resonance Spectroscopy ◽

Membrane Phospholipids

Abnormal cell membrane metabolism is associated with many neuropsychiatric disorders. Free phosphomonoesters and phosphodiesters, which can be detected by in vivo 31P magnetic resonance spectroscopy (MRS), are important cell membrane building blocks. However, the quantification of phosphoesters has been highly controversial even in healthy individuals due to overlapping signals from macromolecule membrane phospholipids (MP). In this study, high signal-to-noise ratio (SNR) cerebral 31P MRS spectra were acquired from healthy volunteers at both 3 and 7 Tesla. Our results indicated that, with minimal spectral interference from MP, the [phosphocreatine (PCr)]/[phosphocholine (PC) + glycerophosphocholine (GPC)] ratio measured at 7 Tesla agreed with its value expected from biochemical constraints. In contrast, the 3 Tesla [PCr]/[PC+GPC] ratio obtained using standard spectral fitting procedures was markedly smaller than the 7 Tesla ratio and than the expected value. The analysis suggests that the commonly used spectral model for MP may fail to capture its complex spectral features at 3 Tesla, and that additional prior knowledge is necessary to reliably quantify the phosphoester signals at low magnetic field strengths when spectral overlapping is significant.

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Feasibility of deuterium magnetic resonance spectroscopy of 3-O-Methylglucose at 7 Tesla

PLoS ONE ◽

10.1371/journal.pone.0252935 ◽

2021 ◽

Vol 16 (6) ◽

pp. e0252935

Author(s):

Benedikt Hartmann ◽

Max Müller ◽

Lisa Seyler ◽

Tobias Bäuerle ◽

Tobias Wilferth ◽

...

Keyword(s):

Magnetic Resonance ◽

Chemical Shift ◽

Magnetic Resonance Spectroscopy ◽

Time Course ◽

Relaxation Times ◽

Exponential Model ◽

7 Tesla ◽

Invasive Technique ◽

Resonance Spectroscopy

Deuterium Magnetic Resonance Spectroscopy (DMRS) is a non-invasive technique that allows the detection of deuterated compounds in vivo. DMRS has a large potential to analyze uptake, perfusion, washout or metabolism, since deuterium is a stable isotope and therefore does not decay during biologic processing of a deuterium labelled substance. Moreover, DMRS allows the distinction between different deuterated substances. In this work, we performed DMRS of deuterated 3-O-Methylglucose (OMG). OMG is a non-metabolizable glucose analog which is transported similar to D-glucose. DMRS of OMG was performed in phantom and in vivo measurements using a preclinical 7 Tesla MRI system. The chemical shift (3.51 ± 0.1 ppm) and relaxation times were determined. OMG was injected intravenously and spectra were acquired over a period of one hour to monitor the time evolution of the deuterium signal in tumor-bearing rats. The increase and washout of OMG could be observed. Three different exponential functions were compared in terms of how well they describe the OMG washout. A mono-exponential model with offset seems to describe the observed time course best with a time constant of 1910 ± 770 s and an offset of 2.5 ± 1.2 mmol/l (mean ± std, N = 3). Chemical shift imaging could be performed with a voxel size of 7.1 mm x 7.1 mm x 7.9 mm. The feasibility of DMRS with deuterium labelled OMG could be demonstrated. These data might serve as basis for future studies that aim to characterize glucose transport using DMRS.

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