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3. Frequency drift in MR spectroscopy at 3T

Author

Hui, SCN, Mikkelsen, M, Zollner, HJ, Ahluwalia, V, Alcauter, S, Baltusis, L, Barany, DA, Barlow, LR, Becker, R, Berman, J, Berrington, A, Bhattacharyya, PK, Blicher, JU, Bogner, W, Brown, MS, Calhoun, VD, Castillo, R, Cecil, KM, Choi, YB, Chu, WCW, Clarke, WT, Craven, AR, Cuypers, K, Dacko, M, de la Fuente-Sandoval, C, Desmond, P, Domagalik, A, Dumont, J, Duncan, NW, Dydak, U, Dyke, K, Edmondson, DA, Ende, G, Ersland, L, Evans, CJ, Fermin, ASR, Ferretti, A, Fillmer, A, Gong, T, Greenhouse, I, Grist, JT, Gu, M, Harris, AD, Hatz, K, Heba, S, Heckova, E, Hegarty, JP, Heise, K-F, Honda, S, Jacobson, A, Jansen, JFA, Jenkins, CW, Johnston, SJ, Juchem, C, Kangarlu, A, Kerr, AB, Landheer, K, Lange, T, Lee, P, Levendovszky, SR, Limperopoulos, C, Liu, F, Lloyd, W, Lythgoe, DJ, Machizawa, MG, MacMillan, EL, Maddock, RJ, Manzhurtsev, A, Martinez-Gudino, ML, Miller, JJ, Mirzakhanian, H, Moreno-Ortega, M, Mullins, PG, Nakajima, S, Near, J, Noeske, R, Nordhoy, W, Oeltzschner, G, Osorio-Duran, R, Otaduy, MCG, Pasaye, EH, Peeters, R, Peltier, SJ, Pilatus, U, Polomac, N, Porges, EC, Pradhan, S, Prisciandaro, JJ, Puts, NA, Rae, CD, Reyes-Madrigal, F, Roberts, TPL, Robertson, CE, Rosenberg, JT, Rotaru, D-G, Tuura, RLO, Saleh, MG, Sandberg, K, Sangill, R, Schembri, K, Schrantee, A, Semenova, NA, Singel, D, Sitnikov, R, Smith, J, Song, Y, Stark, C, Stoffers, D, Swinnen, SP, Tain, R, Tanase, C, Tapper, S, Tegenthoff, M, Thiel, T, Thioux, M, Truong, P, van Dijk, P, Vella, N, Vidyasagar, R, Vovk, A, Wang, G, Westlye, LT, Wilbur, TK, Willoughby, WR, Wilson, M, Wittsack, H-J, Woods, AJ, Wu, Y-C, Xu, J, Lopez, MY, Yeung, DKW, Zhao, Q, Zhou, X, Zupan, G, Edden, RAE, Hui, SCN, Mikkelsen, M, Zollner, HJ, Ahluwalia, V, Alcauter, S, Baltusis, L, Barany, DA, Barlow, LR, Becker, R, Berman, J, Berrington, A, Bhattacharyya, PK, Blicher, JU, Bogner, W, Brown, MS, Calhoun, VD, Castillo, R, Cecil, KM, Choi, YB, Chu, WCW, Clarke, WT, Craven, AR, Cuypers, K, Dacko, M, de la Fuente-Sandoval, C, Desmond, P, Domagalik, A, Dumont, J, Duncan, NW, Dydak, U, Dyke, K, Edmondson, DA, Ende, G, Ersland, L, Evans, CJ, Fermin, ASR, Ferretti, A, Fillmer, A, Gong, T, Greenhouse, I, Grist, JT, Gu, M, Harris, AD, Hatz, K, Heba, S, Heckova, E, Hegarty, JP, Heise, K-F, Honda, S, Jacobson, A, Jansen, JFA, Jenkins, CW, Johnston, SJ, Juchem, C, Kangarlu, A, Kerr, AB, Landheer, K, Lange, T, Lee, P, Levendovszky, SR, Limperopoulos, C, Liu, F, Lloyd, W, Lythgoe, DJ, Machizawa, MG, MacMillan, EL, Maddock, RJ, Manzhurtsev, A, Martinez-Gudino, ML, Miller, JJ, Mirzakhanian, H, Moreno-Ortega, M, Mullins, PG, Nakajima, S, Near, J, Noeske, R, Nordhoy, W, Oeltzschner, G, Osorio-Duran, R, Otaduy, MCG, Pasaye, EH, Peeters, R, Peltier, SJ, Pilatus, U, Polomac, N, Porges, EC, Pradhan, S, Prisciandaro, JJ, Puts, NA, Rae, CD, Reyes-Madrigal, F, Roberts, TPL, Robertson, CE, Rosenberg, JT, Rotaru, D-G, Tuura, RLO, Saleh, MG, Sandberg, K, Sangill, R, Schembri, K, Schrantee, A, Semenova, NA, Singel, D, Sitnikov, R, Smith, J, Song, Y, Stark, C, Stoffers, D, Swinnen, SP, Tain, R, Tanase, C, Tapper, S, Tegenthoff, M, Thiel, T, Thioux, M, Truong, P, van Dijk, P, Vella, N, Vidyasagar, R, Vovk, A, Wang, G, Westlye, LT, Wilbur, TK, Willoughby, WR, Wilson, M, Wittsack, H-J, Woods, AJ, Wu, Y-C, Xu, J, Lopez, MY, Yeung, DKW, Zhao, Q, Zhou, X, Zupan, G, and Edden, RAE

Abstract

PURPOSE: Heating of gradient coils and passive shim components is a common cause of instability in the B0 field, especially when gradient intensive sequences are used. The aim of the study was to set a benchmark for typical drift encountered during MR spectroscopy (MRS) to assess the need for real-time field-frequency locking on MRI scanners by comparing field drift data from a large number of sites. METHOD: A standardized protocol was developed for 80 participating sites using 99 3T MR scanners from 3 major vendors. Phantom water signals were acquired before and after an EPI sequence. The protocol consisted of: minimal preparatory imaging; a short pre-fMRI PRESS; a ten-minute fMRI acquisition; and a long post-fMRI PRESS acquisition. Both pre- and post-fMRI PRESS were non-water suppressed. Real-time frequency stabilization/adjustment was switched off when appropriate. Sixty scanners repeated the protocol for a second dataset. In addition, a three-hour post-fMRI MRS acquisition was performed at one site to observe change of gradient temperature and drift rate. Spectral analysis was performed using MATLAB. Frequency drift in pre-fMRI PRESS data were compared with the first 5:20 minutes and the full 30:00 minutes of data after fMRI. Median (interquartile range) drifts were measured and showed in violin plot. Paired t-tests were performed to compare frequency drift pre- and post-fMRI. A simulated in vivo spectrum was generated using FID-A to visualize the effect of the observed frequency drifts. The simulated spectrum was convolved with the frequency trace for the most extreme cases. Impacts of frequency drifts on NAA and GABA were also simulated as a function of linear drift. Data from the repeated protocol were compared with the corresponding first dataset using Pearson's and intraclass correlation coefficients (ICC). RESULTS: Of the data collected from 99 scanners, 4 were excluded due to various reasons. Thus, data from 95 scanners were ultimately analyzed. For the f

Published
2021

12. Sex-associated differences in mitochondrial function in human peripheral blood mononuclear cells (PBMCs) and brain

Author

Silaidos, Carmina, Pilatus, U., Grewal, Rekha, Matura, S., Lienerth, B., Pantel, J., Eckert, Gunter P., and Justus Liebig University Giessen

Subjects
sex differences, mitochondria, ddc:610, N-acetylaspartate, mitochondrial respiration, MR spectroscopy, blood cells
Abstract

BACKGROUND: Alzheimer´s disease (AD) is the most common form of dementia, and it affects more women than men. Mitochondrial dysfunction (MD) plays a key role in AD, and it is detectable at an early stage of the degenerative process in peripheral tissues, such as peripheral mononuclear blood cells (PBMCs). However, whether these changes are also reflected in cerebral energy metabolism and whether sex-specific differences in mitochondrial function occur are not clear. Therefore, we estimated the correlation between mitochondrial function in PBMCs and brain energy metabolites and examined sex-specific differences in healthy participants to elucidate these issues.METHODS: The current pilot study included 9 male and 15 female healthy adults (mean age 30.8 +/- 7.1 years). Respiration and activity of mitochondrial respiratory complexes were measured using a Clarke-electrode (Oxygraph-2k system), and adenosine triphosphate (ATP) levels were determined using a bioluminescence-based assay in isolated PBMCs. Citrate synthase activity as a mitochondrial marker was measured using a photometric assay. Concentrations of brain energy metabolites were quantified in the same individuals using (1)H-magnetic resonance spectroscopy (MRS).RESULTS: We detected sex-associated differences in mitochondrial function. Mitochondrial complexes I, I+II, and IV and uncoupled respiration and electron transport system (ETS) capacity in PBMCs isolated from blood samples of females were significantly (p < 0.05; p < 0.01) higher compared to males. ATP levels in the PBMCs of female participants were approximately 10% higher compared to males. Citrate synthase (CS) activity, a marker of mitochondrial content, was significantly (p < 0.05) higher in females compared to males. Sex-associated differences were also found for brain metabolites. The N-acetylaspartate (NAA) concentration was significantly higher in female participants compared to males in targeted regions. This difference was observed in white matter (WM) and an area with a high percentage (> 50%) of gray matter (GM) (p < 0.05; p < 0.01). The effect sizes indicated a strong influence of sex on these parameters. Sex-associated differences were found in PBMCs and brain, but the determined parameters were not significantly correlated.CONCLUSIONS: Our study revealed sex-associated differences in mitochondrial function in healthy participants. The underlying mechanisms must be elucidated in more detail, but our study suggests that mitochondrial function in PBMCs is a feasible surrogate marker to detect differences in mitochondrial function and energy metabolism in humans and it underscores the necessity of sex-specific approaches in therapies that target mitochondrial dysfunction.

Published
2018
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14. Effects of aerobic exercise on brain metabolism and grey matter volume in older adults: results of the randomised controlled SMART trial

Author

Matura, S, primary, Fleckenstein, J, additional, Deichmann, R, additional, Engeroff, T, additional, Füzéki, E, additional, Hattingen, E, additional, Hellweg, R, additional, Lienerth, B, additional, Pilatus, U, additional, Schwarz, S, additional, Tesky, V A, additional, Vogt, L, additional, Banzer, W, additional, and Pantel, J, additional

Published
2017
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22. Choline containing compounds in the discrimination between high- and low-grade gliomas - comparison of maximum and mean values

Author

Senft, C., Hattingen, E., Pilatus, U., Franz, K., Seifert, V., and Gasser, T.

Subjects
ddc: 610, 610 Medical sciences, Medicine
Abstract

Objective: In addition to standard MR-protocols, MR-spectroscopy is increasingly used in the characterization of brain tumors, while usually different metabolite ratios are calculated. However, there are great inter-individual and intra-individual differences in many metabolite values, so comparison[for full text, please go to the a.m. URL], 60. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit den Benelux-Ländern und Bulgarien

Published
2009
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38. Effects of coenzyme Q10 in progressive supranuclear palsy

Author

Stamelou, M, primary, Reuss, A, additional, Pilatus, U, additional, Magerkurth, J, additional, Niklowitz, P, additional, Eggert, K, additional, Krisp, A, additional, Menke, T, additional, Brittinger, C, additional, Oertel, W.H, additional, and Hoeglinger, G, additional

Published
2008
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40. H- and C-NMR spectroscopy of Thy-1-APP mice brain extracts indicates metabolic changes in Alzheimer's disease.

Author

Doert, A., Pilatus, U., Zanella, F., Müller, W., and Eckert, G.

Subjects
*NUCLEAR magnetic resonance spectroscopy, *BRAIN physiology, *ALZHEIMER'S disease diagnosis, *LABORATORY mice, *GLUCOSE metabolism, *ALZHEIMER'S patients
Abstract

Biochemical alterations underlying the symptoms and pathomechanisms of Alzheimer's disease (AD) are not fully understood. However, alterations of glucose metabolism and mitochondrial dysfunction certainly play an important role. H- and C-NMR spectroscopy exhibits promising results in providing information about those alterations in vivo in patients and animals, especially regarding the mitochondrial tricarboxylic acid (TCA) cycle. Accordingly, transgenic mice expressing mutant human amyloid precursor protein (APP)-serving as a model of neuropathological changes in AD-were examined with in vitro 1D H- and 2D H-C-HSQC-NMR spectroscopy after oral administration of 1-C-glucose and acquisition of brain material after 30 min. Perchloric acid extracts were measured using a 500 MHz spectrometer, providing more detailed information compared to in vivo spectra achievable nowadays. Area under curve (AUC) data of metabolite peaks were obtained and normalized in relation to the creatine signal, serving as internal reference. Besides confirming well-known metabolic alterations in AD like decreased N-acetylaspartate (NAA)/Creatine (Cr) ratio, new findings such as a decrease in phosphorylcholine (PC) are presented. Glutamate (Glu) and glutamine (Gln) concentrations were decreased while γ-aminobutyric acid (GABA) was elevated in Thy1-APP mice. C-NMR spectroscopy revealed a shift in the Glx-2/Glx-4-ratio-where Glx represents a combined Glu/Gln-signal-towards Glx-2 in AD. These findings correlated well with the NAA/Cr-ratio. The Gln-4/Glu-4-ratio is altered in favor of Glu. Our findings suggest that glutamine synthetase (GS), which is predominantly present in glial cells may be impaired in the brain of Thy1-APP transgenic mice. Since GS is an ATP-dependent enzyme, mitochondrial dysfunction might contribute to reduced activity, which might also account for the increased metabolism of glutamate via the GABA shunt, a metabolic pathway to bypass intra-mitochondrial α-ketoglutarate-dehydrogenase, resulting in elevated GABA levels. [ABSTRACT FROM AUTHOR]

Published
2015
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50. Objectification and quantification of the cognitive impairment from an existing HIV infection or HIV encephalopathy using magnetic resonance spectroscopy.

Author

Arneth, B, Pilatus, U, Lanfermann, H, and Enzensberger, W

Abstract

Some patients with HIV develop dementia. Using in vivo proton nuclear magnetic resonance ((1)H-NMR) spectroscopy, it is possible to measure the metabolic changes noninvasively. In this study, it is of interest to answer the clinically relevant question of whether magnetic resonance spectroscopy is suitable for the diagnosis of HIV encephalopathy. In total, 14 HIV-positive patients were investigated by means of localized (1)H-NMR spectroscopy in the following locations: (1) the mid-parietal gray matter, (2) the parietal white matter (PWM), and (3) the frontal white matter. All patients had no other brain diseases, apart from the HIV encephalopathy. The clinical extent of HIV encephalopathy of each patient was investigated using the following tests: (1) an electroencephalogram, (2) a neurological examination and psychiatric assessment, and (3) a psychometrical test. The spectroscopic changes in the PWM were more pronounced than those in the cortex, and the myo-inositol/creatine (mI/Cr) signal showed a clear increase in the cortex. Overall, the mI/Cr ratio emerged as the most reliable and earliest parameter to indicate an HIV encephalopathy. [ABSTRACT FROM AUTHOR]

Published
2013
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