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Höger SA, Gast LV, Marty B, Hotfiel T, Bickelhaupt S, Uder M, Heiss R, Nagel AM. Sodium and quantitative hydrogen parameter changes in muscle tissue after eccentric exercise and in delayed-onset muscle soreness assessed with magnetic resonance imaging. NMR IN BIOMEDICINE 2023; 36:e4840. [PMID: 36196511 DOI: 10.1002/nbm.4840] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 09/11/2022] [Accepted: 09/23/2022] [Indexed: 06/16/2023]
Abstract
The objective of the current study was to assess sodium (23 Na) and quantitative proton (1 H) parameter changes in muscle tissue with magnetic resonance imaging (MRI) after eccentric exercise and in delayed-onset muscle soreness (DOMS). Fourteen participants (mean age: 25 ± 4 years) underwent 23 Na/1 H MRI of the calf muscle on a 3-T MRI system before exercise (t0), directly after eccentric exercise (t1), and 48 h postintervention (t2). In addition to tissue sodium concentration (TSC), intracellular-weighted sodium (ICwS) signal was acquired using a three-dimensional density-adapted radial projection readout with an additional inversion recovery preparation module. Phantoms containing saline solution served as references to quantify sodium concentrations. The 1 H MRI protocol consisted of a T1 -weighted turbo spin echo sequence, a T2 -weighted turbo inversion recovery, as well as water T2 mapping and water T1 mapping. Additionally, blood serum creatine kinase (CK) levels were assessed at baseline and 48 h after exercise. The TSC and ICwS of exercised muscles increased significantly from t0 to t1 and decreased significantly from t1 to t2. In the soleus muscle (SM), ICwS decreased below baseline values at t2. In the tibialis anterior muscle (TA), TSC and ICwS remained at baseline levels at each measurement point. However, high-CK participants (i.e., participants with a more than 10-fold CK increase, n = 3) displayed different behavior, with 2- to 4-fold increases in TSC values in the medial gastrocnemius muscle (MGM) at t2. 1 H water T1 relaxation times increased significantly after 48 h in the MGM and SM. 1 H water T2 relaxation times and muscle volume increased in the MGM at t2. Sodium MRI parameters and water relaxation times peaked at different points. Whereas water relaxation times were highest at t2, sodium MRI parameters had already returned to baseline values (or even below baseline values, for low-CK participants) by this point. The observed changes in ion concentrations and water relaxation time parameters could enable a better understanding of the physiological processes during DOMS and muscle regeneration. In the future, this might help to optimize training and to reduce associated sports injuries.
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Affiliation(s)
- Svenja A Höger
- 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
| | - Benjamin Marty
- NMR Laboratory, Neuromuscular Investigation Center, Institute of Myology, Paris, France
- NMR Laboratory, CEA/DRF/IBFJ/MIRCen, Paris, France
| | - Thilo Hotfiel
- Department of Orthopedic Surgery, Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
- Center for Musculoskeletal Surgery Osnabrück (OZMC), Klinikum Osnabrück, Osnabrück, Germany
| | - Sebastian Bickelhaupt
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Michael Uder
- Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Rafael Heiss
- 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
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Zaeske C, Brueggemann GP, Willwacher S, Maehlich D, Maintz D, Bratke G. The behaviour of T2* and T2 relaxation time in extrinsic foot muscles under continuous exercise: A prospective analysis during extended running. PLoS One 2022; 17:e0264066. [PMID: 35176114 PMCID: PMC8893273 DOI: 10.1371/journal.pone.0264066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 02/02/2022] [Indexed: 12/02/2022] Open
Abstract
Objectives Previous studies on T2* and T2 relaxation time of the muscles have shown that exercise leads to an initial increase, presumably representing different intramuscular physiological processes such as increase in intracellular volume or blood oxygenation level dependent effects with a subsequent decrease after cessation of exercise. Their behaviour during prolonged exercise is still unknown but could provide important information for example about the pathophysiology of overuse injuries. The aim of this study was to evaluate the temporal course of T2* and T2 relaxation time in extrinsic foot muscles during prolonged exercise and determine the optimal mapping technique. Methods Ten participants had to run a total of 75 minutes at their individual highest possible running speed, with interleaved MR scans at baseline and after 2.5, 5, 10, 15, 45 and 75 minutes. The examined extrinsic foot muscles were manually segmented, and relaxation time were analysed regarding its respective time course. Results T2* and T2 relaxation time showed an initial increase, followed by a plateau phase between 2.5 and 15 minutes and a subsequent decrease. For the T2* relaxation time, this pattern was also apparent, but less pronounced, with more muscles not reaching significance (p<0.05) when comparing different time points. Conclusions T2* and T2 relaxation time showed a similar course with an initial rapid increase, a plateau phase and a subsequent decrease under prolonged exercise. Moderate but long-term muscular activity appears to have a weaker effect on T2* relaxation time than on T2 relaxation time.
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Affiliation(s)
- Charlotte Zaeske
- Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
- * E-mail:
| | | | - Steffen Willwacher
- Institute of Biomechanics and Orthopaedics, German Sport University, Cologne, Germany
| | - Daniela Maehlich
- Institute of Biomechanics and Orthopaedics, German Sport University, Cologne, Germany
| | - David Maintz
- Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Grischa Bratke
- Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
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3
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Lee JH, Yoon YC, Kim HS, Lee J, Kim E, Findeklee C, Katscher U. In vivo electrical conductivity measurement of muscle, cartilage, and peripheral nerve around knee joint using MR-electrical properties tomography. Sci Rep 2022; 12:73. [PMID: 34996978 PMCID: PMC8741940 DOI: 10.1038/s41598-021-03928-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 12/10/2021] [Indexed: 11/20/2022] Open
Abstract
This study aimed to investigate whether in vivo MR-electrical properties tomography (MR-EPT) is feasible in musculoskeletal tissues by evaluating the conductivity of muscle, cartilage, and peripheral nerve around the knee joint, and to explore whether these measurements change after exercise. This prospective study was approved by the institutional review board. On February 2020, ten healthy volunteers provided written informed consent and underwent MRI of the right knee using a three-dimensional balanced steady-state free precession (bSSFP) sequence. To test the effect of loading, the subjects performed 60 squatting exercises after baseline MRI, immediately followed by post-exercise MRI with the same sequences. After reconstruction of conductivity map based on the bSSFP sequence, conductivity of muscles, cartilages, and nerves were measured. Measurements between the baseline and post-exercise MRI were compared using the paired t-test. Test–retest reliability for baseline conductivity was evaluated using the intraclass correlation coefficient. The baseline and post-exercise conductivity values (mean ± standard deviation) [S/m] of muscles, cartilages, and nerves were 1.73 ± 0.40 and 1.82 ± 0.50 (p = 0.048), 2.29 ± 0.47 and 2.51 ± 0.37 (p = 0.006), and 2.35 ± 0.57 and 2.36 ± 0.57 (p = 0.927), respectively. Intraclass correlation coefficient for the baseline conductivity of muscles, cartilages, and nerves were 0.89, 0.67, and 0.89, respectively. In conclusion, in vivo conductivity measurement of musculoskeletal tissues is feasible using MR-EPT. Conductivity of muscles and cartilages significantly changed with an overall increase after exercise.
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Affiliation(s)
- Ji Hyun Lee
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, 06351, Seoul, Korea
| | - Young Cheol Yoon
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, 06351, Seoul, Korea.
| | - Hyun Su Kim
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, 06351, Seoul, Korea
| | - Jiyeong Lee
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, 06351, Seoul, Korea
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4
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Haddock B, Hansen SK, Lindberg U, Nielsen JL, Frandsen U, Aagaard P, Larsson HBW, Suetta C. Exercise-induced fluid shifts are distinct to exercise mode and intensity: a comparison of blood flow-restricted and free-flow resistance exercise. J Appl Physiol (1985) 2021; 130:1822-1835. [PMID: 33914664 DOI: 10.1152/japplphysiol.01012.2020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
MRI can provide fundamental tools in decoding physiological stressors stimulated by training paradigms. Acute physiological changes induced by three diverse exercise protocols known to elicit similar levels of muscle hypertrophy were evaluated using muscle functional magnetic resonance imaging (mfMRI). The study was a cross-over study with participants (n = 10) performing three acute unilateral knee extensor exercise protocols to failure and a work matched control exercise protocol. Participants were scanned after each exercise protocol; 70% 1 repetition maximum (RM) (FF70); 20% 1RM (FF20); 20% 1RM with blood flow restriction (BFR20); free-flow (FF) control work matched to BFR20 (FF20WM). Post exercise mfMRI scans were used to obtain interleaved measures of muscle R2 (indicator of edema), R2' (indicator of deoxyhemoglobin), muscle cross sectional area (CSA) blood flow, and diffusion. Both BFR20 and FF20 exercise resulted in a larger acute decrease in R2, decrease in R2', and expansion of the extracellular compartment with slower rates of recovery. BFR20 caused greater acute increases in muscle CSA than FF20WM and FF70. Only BFR20 caused acute increases in intracellular volume. Postexercise muscle blood flow was higher after FF70 and FF20 exercise than BFR20. Acute changes in mean diffusivity were similar across all exercise protocols. This study was able to differentiate the acute physiological responses between anabolic exercise protocols. Low-load exercise protocols, known to have relatively higher energy contributions from glycolysis at task failure, elicited a higher mfMRI response. Noninvasive mfMRI represents a promising tool for decoding mechanisms of anabolic adaptation in muscle.NEW & NOTEWORTHY Using muscle functional MRI (mfMRI), this study was able to differentiate the acute physiological responses following three established hypertrophic resistance exercise strategies. Low-load exercise protocols performed to failure, with or without blood flow restriction, resulted in larger changes in R2 (i.e. greater T2-shifts) with a slow rate of return to baseline indicative of myocellular fluid shifts. These data were cross evaluated with interleaved measures of macrovascular blood flow, water diffusion, muscle cross sectional area (i.e. acute macroscopic muscle swelling), and intracellular water fraction measured using MRI.
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Affiliation(s)
- Bryan Haddock
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Sofie K Hansen
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.,Geriatric Research Unit, Department of Geriatric and Palliative Medicine, Bispebjerg and Frederiksberg Hospital, Copenhagen University Hospital, Copenhagen, Denmark
| | - Ulrich Lindberg
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Jakob Lindberg Nielsen
- Department of Sport Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Ulrik Frandsen
- Department of Sport Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Per Aagaard
- Department of Sport Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Henrik B W Larsson
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.,Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Charlotte Suetta
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.,Geriatric Research Unit, Department of Geriatric and Palliative Medicine, Bispebjerg and Frederiksberg Hospital, Copenhagen University Hospital, Copenhagen, Denmark.,Geriatric Research Unit, Department of Medicine Herlev and Gentofte Hospital, Copenhagen University Hospital, Copenhagen, Denmark
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5
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Insights into extrinsic foot muscle activation during a 75 min run using T2 mapping. Sci Rep 2021; 11:7331. [PMID: 33795777 PMCID: PMC8016869 DOI: 10.1038/s41598-021-86810-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Accepted: 03/18/2021] [Indexed: 11/09/2022] Open
Abstract
The extrinsic foot muscles are essentially for controlling the movement path but our knowledge of their behavior during prolonged running is still very limited. Therefore, this study analyzed the time-course of muscle activation using T2 mapping during 75 min of running. In this prospective study, 19 recreational active runners completed 75 min of treadmill running at a constant speed. Interleaved T2 mapping sequences were acquired and segmented at timepoints 0, 2.5, 5, 10, 15, 45, and 75 min. ANOVA for repeated measurements followed by a Tukey post hoc test and Pearson correlation between running speed and initial signal increase at 2.5 min were calculated. All muscles showed a significant signal increase between baseline and 2.5 min (e.g. medial gastrocnemius: + 15.48%; p < 0.01). This was followed by a plateau phase till 15 min for all but the extensor digitorum longus muscle and a significant decrease at 45 or 75 min for all muscles (all p < 0.05). Correlation between running speed and signal increase was negative for all muscles and significant for both gastrocnemii (e.g. medial: r = - 0.57, p = 0.0104) and soleus (r = - 0.47, p = 0.0412). The decrease of relaxation times times in the later running phases was less pronounced for faster runners (≥ 10 km/h). T2 relaxation times do not only decrease after cessation of exercise but already during prolonged running. The lesser initial increase and later decrease in faster runners may indicate training induced changes.
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6
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Haddock B, Hansen SK, Lindberg U, Nielsen JL, Frandsen U, Aagaard P, Larsson HBW, Suetta C. Physiological responses of human skeletal muscle to acute blood flow restricted exercise assessed by multimodal MRI. J Appl Physiol (1985) 2020; 129:748-759. [PMID: 32853108 DOI: 10.1152/japplphysiol.00171.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Important physiological quantities for investigating muscle hypertrophy include blood oxygenation, cell swelling, and changes in blood flow. The purpose of this study was to compare the acute changes of these parameters in human skeletal muscle induced by low-load (20% 1-RM) blood flow-restricted (BFR-20) knee extensor exercise compared with free-flow work-matched (FF-20WM) and free-flow 50% 1-RM (FF-50) knee extensor exercise using multimodal magnetic resonance imaging (MRI). Subjects (n = 11) completed acute exercise sessions for each exercise mode in an MRI scanner, where interleaved measures of muscle R2 (indicator of edema), [Formula: see text] (indicator of deoxyhemoglobin), macrovascular blood flow, and diffusion were performed before, between sets, and after the final set for each exercise protocol. BFR-20 exercise resulted in larger acute decreases in R2 and greater increases in cross-sectional area than FF-20WM and FF-50 (P < 0.01). Blood oxygenation decreased between sets during BFR-20, as indicated by a 13.6% increase in [Formula: see text] values (P < 0.01)), whereas they remained unchanged for FF-20WM and decreased during FF-50 exercise. Quadriceps blood flow between sets was highest for the heavier load (FF-50), averaging 305 mL/min, and lowest for BFR-20 at 123 ± 73 mL/min until post-exercise cuff release, where blood flow rates in BFR-20 exceeded both FF protocols (P < 0.01). Acute changes in diffusion rates were similar for all exercise protocols. This study was able to differentiate the acute exercise response of selected physiological factors associated with skeletal muscle hypertrophy. Marked differences in these parameters were found to exist between BFR and FF exercise conditions, which contribute to explain the anabolic potential of low-load blood flow restricted muscle exercise.NEW & NOTEWORTHY Acute changes in blood flow, diffusion, blood oxygenation, cross-sectional area, and the "T2 shift" are evaluated in human skeletal muscle in response to blood flow-restricted (BFR) and conventional free-flow knee extensor exercise performed in an MRI scanner. The acute physiological response to exercise was dependent on the magnitude of load and the application of BFR. Physiological variables changed markedly and established a steady state rapidly after the first of four exercise sets.
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Affiliation(s)
- Bryan Haddock
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Sofie K Hansen
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.,Geriatric Research Unit, Bispebjerg-Frederiksberg and Herlev-Gentofte Hospitals, Copenhagen University Hospital, Copenhagen, Denmark
| | - Ulrich Lindberg
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Jakob Lindberg Nielsen
- Department of Sport Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Ulrik Frandsen
- Department of Sport Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Per Aagaard
- Department of Sport Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Henrik B W Larsson
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.,Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Charlotte Suetta
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.,Geriatric Research Unit, Bispebjerg-Frederiksberg and Herlev-Gentofte Hospitals, Copenhagen University Hospital, Copenhagen, Denmark
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7
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Marty B, Lopez Kolkovsky AL, Araujo ECA, Reyngoudt H. Quantitative Skeletal Muscle Imaging Using 3D MR Fingerprinting With Water and Fat Separation. J Magn Reson Imaging 2020; 53:1529-1538. [PMID: 32996670 DOI: 10.1002/jmri.27381] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 09/14/2020] [Accepted: 09/15/2020] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Quantitative muscle MRI is a robust tool to monitor intramuscular fatty replacement and disease activity in patients with neuromuscular disorders (NMDs). PURPOSE To implement a 3D sequence for quantifying simultaneously fat fraction (FF) and water T1 (T1,H2O ) in the skeletal muscle, evaluate regular undersampling in the partition-encoding direction, and compare it to a recently proposed 2D MR fingerprinting sequence with water and fat separation (MRF T1 -FF). STUDY TYPE Prospective. PHANTOM/SUBJECTS Seventeen-vial phantom at different FF and T1,H2O , 11 healthy volunteers, and 6 subjects with different NMDs. FIELD STRENGTH/SEQUENCE 3T/3D MRF T1 -FF, 2D MRF T1 -FF, STEAM MRS ASSESSMENT: FF and T1,H2O measured with the 2D and 3D sequences were compared in the phantom and in vivo at different undersampling factors (US). Data were acquired in healthy subjects before and after plantar dorsiflexions and at rest in patients. STATISTICAL TESTS Linear correlations, Bland-Altman analysis, two-way repeated measures analysis of variance (ANOVA), Student's t-test. RESULTS Up to a US factor of 3, the undersampled acquisitions were in good agreement with the fully sampled sequence (R2 ≥ 0.98, T1,H2O bias ≤10 msec, FF bias ≤4 × 10-4 ) both in phantom and in vivo. The 2D and 3D MRF T1 -FF sequences provided comparable T1,H2O and FF values (R2 ≥ 0.95, absolute T1,H2O bias ≤35 msec, and absolute FF bias ≤0.003). The plantar dorsiflexion induced a significant increase of T1,H2O in the tibialis anterior and extensor digitorum (relative increase of +10.8 ± 1.7% and + 7.7 ± 1.4%, respectively, P < 0.05), that was accompanied by a significant reduction of FF in the tibialis anterior (relative decrease of -16.3 ± 4.0%, P < 0.05). Some subjects with NMDs presented increased and heterogeneous T1,H2O and FF values throughout the leg. DATA CONCLUSION Quantitative 3D T1,H2O and FF maps covering the entire leg were obtained within acquisition times compatible with clinical research (4 minutes 20 seconds) and a 1 × 1 × 5 mm3 spatial resolution. LEVEL OF EVIDENCE 2 TECHNICAL EFFICACY: Stage 2.
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Affiliation(s)
- Benjamin Marty
- Neuromuscular Investigation Center, NMR Laboratory, Institute of Myology, Paris, France.,CEA, DRF, IBFJ, MIRCen, NMR Laboratory, Paris, France
| | - Alfredo L Lopez Kolkovsky
- Neuromuscular Investigation Center, NMR Laboratory, Institute of Myology, Paris, France.,CEA, DRF, IBFJ, MIRCen, NMR Laboratory, Paris, France
| | - Ericky C A Araujo
- Neuromuscular Investigation Center, NMR Laboratory, Institute of Myology, Paris, France.,CEA, DRF, IBFJ, MIRCen, NMR Laboratory, Paris, France
| | - Harmen Reyngoudt
- Neuromuscular Investigation Center, NMR Laboratory, Institute of Myology, Paris, France.,CEA, DRF, IBFJ, MIRCen, NMR Laboratory, Paris, France
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Tashiro K, Kobayashi T, Shiotani S, Saitou H, Kaga K, Someya S, Yoshida M, Yamamori M, Kamimura Y, Kuramochi R, Miyamoto K, Hayakawa H, Muranaka H, Homma K. Skeletal muscular relaxation time from postmortem MR imaging of adult humans. FORENSIC IMAGING 2020. [DOI: 10.1016/j.fri.2020.200399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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9
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Willwacher S, Sleboda DA, Mählich D, Brüggemann G, Roberts TJ, Bratke G. The time course of calf muscle fluid volume during prolonged running. Physiol Rep 2020; 8:e14414. [PMID: 32378332 PMCID: PMC7202985 DOI: 10.14814/phy2.14414] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 03/16/2020] [Indexed: 01/30/2023] Open
Abstract
Muscle fluid is essential for the biochemistry and the biomechanics of muscle contraction. Here, we provide evidence that muscle fluid volumes undergo significant changes during 75 min of moderate intensity (2.7 ± 0.4 m/s) running. Using MRI measurements at baseline and after 2.5, 5, 10, 15, 45 and 75 min, we found that the volumes of calf muscles (quantified through average cross-sectional area) in 18 young recreational runners increase (up to 9% in the gastrocnemii) at the beginning and decrease (below baseline levels) at later stages of running. However, the intensity of changes varied between analyzed muscles. We speculate that these changes are induced by muscle activity and dehydration-related changes in osmotic pressure gradients between intramuscular and extramuscular spaces. These findings highlight the complex nature of muscle fluid shifts during prolonged running exercise.
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Affiliation(s)
- Steffen Willwacher
- Institute of Biomechanics and OrthopaedicsGerman Sport University CologneCologneGermany
- School of Human Movement and Nutrition SciencesThe University of QueenslandSt LuciaQueenslandAustralia
| | - David A. Sleboda
- Department of Ecology and Evolutionary BiologyBrown UniversityProvidenceRIUSA
| | - Daniela Mählich
- Institute of Biomechanics and OrthopaedicsGerman Sport University CologneCologneGermany
| | - Gert‐Peter Brüggemann
- Institute of Biomechanics and OrthopaedicsGerman Sport University CologneCologneGermany
| | - Thomas J. Roberts
- Department of Ecology and Evolutionary BiologyBrown UniversityProvidenceRIUSA
| | - Grischa Bratke
- Department of Diagnostic and Interventional RadiologyUniversity of CologneCologneGermany
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10
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Niess F, Schmid AI, Bogner W, Wolzt M, Carlier P, Trattnig S, Moser E, Meyerspeer M. Interleaved 31 P MRS/ 1 H ASL for analysis of metabolic and functional heterogeneity along human lower leg muscles at 7T. Magn Reson Med 2019; 83:1909-1919. [PMID: 31846116 PMCID: PMC7065182 DOI: 10.1002/mrm.28088] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 10/16/2019] [Accepted: 10/28/2019] [Indexed: 12/16/2022]
Abstract
PURPOSE MR offers the unique possibility to noninvasively investigate cellular energy metabolism via 31P MRS, while blood perfusion, which provides oxygen and substrates to the tissue, is accessible by arterial spin labeling (ASL) 1H MRI. Because metabolic and hemodynamic parameters are linked, it would be desirable to study them simultaneously. A 3D-resolved method is presented that allows such measurements with high spatiotemporal resolution and has the potential to discern differences along an exercising muscle. METHODS Multi-voxel localized 31 P MRS was temporally interleaved with multi-slice pASL 1H MRI. Phosphorus spectra were collected from two adjacent positions in gastrocnemius medialis (GM) during rest, submaximal plantar flexion exercise and recovery, while perfusion and T 2 * -weighted axial images were acquired at the same time. Seventeen healthy volunteers (9 f / 8 m) were studied at 7 T. RESULTS An increase of postexercise perfusion and T 2 * -weighted signal in GM positively correlated with end-exercise PCr depletion and pH drop. At proximal positions functional and metabolic activity was higher than distally, that is, perfusion increase and peak T 2 * -weighted signal, end-exercise PCr depletion, end-exercise pH, and PCr recovery time constant were significantly different. An NOE-induced SNR increase of approximately 20 % (P < .001), at rest, was found in interleaved 31 P spectra, when comparing to 31 P-only acquisitions. CONCLUSIONS A technique for fast, simultaneous imaging of muscle functional heterogeneity in ASL, T 2 * and acquisition of time-resolved 31 P MRS data is presented. These single exercise recovery experiments can be used to investigate local variations during disease progression in patients suffering from vascular or muscular diseases.
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Affiliation(s)
- Fabian Niess
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,High Field MR Center, Medical University of Vienna, Vienna, Austria
| | - Albrecht Ingo Schmid
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,High Field MR Center, Medical University of Vienna, Vienna, Austria
| | - Wolfgang Bogner
- High Field MR Center, Medical University of Vienna, Vienna, Austria.,Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Michael Wolzt
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | | | - Siegfried Trattnig
- High Field MR Center, Medical University of Vienna, Vienna, Austria.,Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Ewald Moser
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,High Field MR Center, Medical University of Vienna, Vienna, Austria
| | - Martin Meyerspeer
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,High Field MR Center, Medical University of Vienna, Vienna, Austria
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11
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Fouré A, Troter A, Ogier AC, Guye M, Gondin J, Bendahan D. Spatial difference can occur between activated and damaged muscle areas following electrically‐induced isometric contractions. J Physiol 2019; 597:4227-4236. [DOI: 10.1113/jp278205] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 06/27/2019] [Indexed: 11/08/2022] Open
Affiliation(s)
- Alexandre Fouré
- Aix‐Marseille UniversitéCNRS, CRMBM UMR 7339 13385 Marseille France
- APHMHôpital Universitaire Timone CEMEREM 13005 Marseille France
- Université de Lyon (UCBL1)Laboratoire Interuniversitaire de Biologie de la MotricitéEA7424 Villeurbanne France
| | - Arnaud Troter
- Aix‐Marseille UniversitéCNRS, CRMBM UMR 7339 13385 Marseille France
| | - Augustin C. Ogier
- Aix‐Marseille UniversitéUniversité de Toulon, CNRS LIS UMR 7020 13385 Marseille France
| | - Maxime Guye
- Aix‐Marseille UniversitéCNRS, CRMBM UMR 7339 13385 Marseille France
- APHMHôpital Universitaire Timone CEMEREM 13005 Marseille France
| | - Julien Gondin
- Aix‐Marseille UniversitéCNRS, CRMBM UMR 7339 13385 Marseille France
- Institut NeuroMyoGène, Université de Lyon (UCBL1)CNRS 5310 INSERM U1217 Lyon France
| | - David Bendahan
- Aix‐Marseille UniversitéCNRS, CRMBM UMR 7339 13385 Marseille France
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12
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Marty B, Carlier PG. Physiological and pathological skeletal muscle T1 changes quantified using a fast inversion-recovery radial NMR imaging sequence. Sci Rep 2019; 9:6852. [PMID: 31048765 PMCID: PMC6497638 DOI: 10.1038/s41598-019-43398-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 04/24/2019] [Indexed: 12/18/2022] Open
Abstract
We investigated the response of skeletal muscle global T1 under different physiological and pathological conditions using an inversion-recovery radial T1 mapping sequence. Thirty five healthy volunteers, seven patients with Becker muscular dystrophy (BMD) and seven patients with sporadic inclusion body myositis (IBM) were investigated in order to evaluate the effects of gender, age, muscle group, exercise and pathological processes on global T1 values. In addition, the intramuscular fat content was measured using 3-point Dixon and the global T2 and water T2 (T2H2O) were determined with a multi-spin-echo sequence. In the muscles of healthy volunteers, there was no impact of age on global T1. However, we measured a significant effect of sex and muscle group. After exercise, a significant 7.7% increase of global T1 was measured in the recruited muscles, and global T1 variations were highly correlated to T2H2O variations (R = 0.91). In pathologies, global T1 values were reduced in fat infiltrated muscles. When fat fraction was taken into account, global T1 values were higher in IBM patients compared to BMD. Global T1 variations are a sensitive indicator of tissue changes in skeletal muscle related to several physiological and pathological events.
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Affiliation(s)
- Benjamin Marty
- Institute of Myology, Neuromuscular Investigation Center, NMR Laboratory, Paris, France. .,CEA, DRF, IBFJ, MIRCen, NMR Laboratory, Paris, France.
| | - Pierre G Carlier
- Institute of Myology, Neuromuscular Investigation Center, NMR Laboratory, Paris, France.,CEA, DRF, IBFJ, MIRCen, NMR Laboratory, Paris, France
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13
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Berry DB, Regner B, Galinsky V, Ward SR, Frank LR. Relationships between tissue microstructure and the diffusion tensor in simulated skeletal muscle. Magn Reson Med 2018; 80:317-329. [PMID: 29090480 PMCID: PMC5876103 DOI: 10.1002/mrm.26993] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 10/11/2017] [Accepted: 10/12/2017] [Indexed: 12/21/2022]
Abstract
PURPOSE To establish a series of relationships defining how muscle microstructure and diffusion tensor imaging (DTI) are related. METHODS The relationship among key microstructural features of skeletal muscle (fiber size, fibrosis, edema, and permeability) and the diffusion tensor were systematically simulated over physiologically relevant dimensions individually, and in combination, using a numerical simulation application. Stepwise multiple regression was used to identify which microstructural features of muscle significantly predict the diffusion tensor using single-echo and multi-echo DTI pulse sequences. Simulations were also performed in models with histology-informed geometry to investigate the relationship between fiber size and the diffusion tensor in models with real muscle geometry. RESULTS Fiber size is the strongest predictor of λ2, λ3, mean diffusivity, and fractional anisotropy in skeletal muscle, accounting for approximately 40% of the variance in the diffusion model when calculated with single-echo DTI. This increased to approximately 70% when diffusion measures were calculated from the short T2 component of the multi-echo DTI sequence. This nonlinear relationship begins to plateau in fibers with greater than 60-μm diameter. CONCLUSIONS As the normal fiber size of a human muscle fiber is 40 to 60 μm, this suggests that DTI is a sensitive tool to monitor muscle atrophy, but may be limited in measurements of muscle with larger fibers. Magn Reson Med 80:317-329, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- David B Berry
- Department of Bioengineering, University of California San Diego, La Jolla, California, USA
| | - Benjamin Regner
- Institute of Engineering in Medicine, San Diego, California, USA
| | - Vitaly Galinsky
- Institute of Engineering in Medicine, San Diego, California, USA
| | - Samuel R Ward
- Department of Bioengineering, University of California San Diego, La Jolla, California, USA
- Department of Radiology, University of California San Diego, La Jolla, California, USA
- Department of Orthopedic Surgery, University of California San Diego, La Jolla, California, USA
| | - Lawrence R Frank
- Department of Radiology, University of California San Diego, La Jolla, California, USA
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14
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Hooijmans MT, Niks EH, Burakiewicz J, Verschuuren JJGM, Webb AG, Kan HE. Elevated phosphodiester and T 2 levels can be measured in the absence of fat infiltration in Duchenne muscular dystrophy patients. NMR IN BIOMEDICINE 2017; 30:e3667. [PMID: 27859827 DOI: 10.1002/nbm.3667] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 10/10/2016] [Accepted: 10/10/2016] [Indexed: 05/27/2023]
Abstract
Quantitative MRI and MRS are increasingly important as non-invasive outcome measures in therapy development for Duchenne muscular dystrophy (DMD). Many studies have focussed on individual measures such as fat fraction and metabolite levels in relation to age and functionality, but much less attention has been given to how these indices relate to each other. Here, we assessed spatially resolved metabolic changes in leg muscles of DMD patients, and classified muscles according to the degree of fat replacement compared with healthy controls. Quantitative MRI (three-point Dixon and multi-spin echo without fat suppression and a tri-exponential fit) and 2D-CSI 31 P MRS scans were obtained from 18 DMD patients and 12 healthy controls using a 3 T and a 7 T MR scanner. Metabolite levels, T2 values and fat fraction were individually assessed for five lower leg muscles. In muscles with extensive fat replacement, phosphodiester over adenosine triphosphate (PDE/ATP), inorganic phosphate over phosphocreatine, intracellular tissue pH and T2 were significantly increased compared with healthy controls. In contrast, in muscles without extensive fat replacement, only PDE/ATP and T2 values were significantly elevated. Overall, our results show that PDE levels and T2 values increase prior to the occurrence of fat replacement and remain elevated in later stages of the disease. This suggests that these individual measures could not only function as early markers for muscle damage but also reflect potentially reversible pathology in the more advanced stages.
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Affiliation(s)
- M T Hooijmans
- Department of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
| | - E H Niks
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - J Burakiewicz
- Department of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
| | - J J G M Verschuuren
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - A G Webb
- Department of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
| | - H E Kan
- Department of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
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15
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Muller MD, Li Z, Sica CT, Luck JC, Gao Z, Blaha CA, Cauffman AE, Ross AJ, Winkler NJR, Herr MD, Brandt K, Wang J, Gallagher DC, Karunanayaka P, Vesek J, Leuenberger UA, Yang QX, Sinoway LI. Muscle oxygenation during dynamic plantar flexion exercise: combining BOLD MRI with traditional physiological measurements. Physiol Rep 2016; 4:4/20/e13004. [PMID: 27798357 PMCID: PMC5099966 DOI: 10.14814/phy2.13004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 09/26/2016] [Indexed: 11/24/2022] Open
Abstract
Blood-oxygen-level-dependent magnetic resonance imaging (BOLD MRI) has the potential to quantify skeletal muscle oxygenation with high temporal and high spatial resolution. The purpose of this study was to characterize skeletal muscle BOLD responses during steady-state plantar flexion exercise (i.e., during the brief rest periods between muscle contraction). We used three different imaging modalities (ultrasound of the popliteal artery, BOLD MRI, and near-infrared spectroscopy [NIRS]) and two different exercise intensities (2 and 6 kg). Six healthy men underwent three separate protocols of dynamic plantar flexion exercise on separate days and acute physiological responses were measured. Ultrasound studies showed the percent change in popliteal velocity from baseline to the end of exercise was 151 ± 24% during 2 kg and 589 ± 145% during 6 kg. MRI studies showed an abrupt decrease in BOLD signal intensity at the onset of 2 kg exercise, indicating deoxygenation. The BOLD signal was further reduced during 6 kg exercise (compared to 2 kg) at 1 min (-4.3 ± 0.7 vs. -1.2 ± 0.4%, P < 0.001). Similarly, the change in the NIRS muscle oxygen saturation in the medial gastrocnemius was -11 ± 4% at 2 kg and -38 ± 11% with 6 kg (P = 0.041). In conclusion, we demonstrate that BOLD signal intensity decreases during plantar flexion and this effect is augmented at higher exercise workloads.
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Affiliation(s)
- Matthew D Muller
- Penn State Hershey Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Zhijun Li
- Department of Radiology, Center for NMR Research, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Christopher T Sica
- Department of Radiology, Center for NMR Research, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - J Carter Luck
- Penn State Hershey Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Zhaohui Gao
- Penn State Hershey Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Cheryl A Blaha
- Penn State Hershey Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Aimee E Cauffman
- Penn State Hershey Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Amanda J Ross
- Penn State Hershey Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Nathan J R Winkler
- Penn State Hershey Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Michael D Herr
- Penn State Hershey Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Kristen Brandt
- Penn State Hershey Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Jianli Wang
- Department of Radiology, Center for NMR Research, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - David C Gallagher
- Department of Radiology, Center for NMR Research, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Prasanna Karunanayaka
- Department of Radiology, Center for NMR Research, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Jeffrey Vesek
- Department of Radiology, Center for NMR Research, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Urs A Leuenberger
- Penn State Hershey Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Qing X Yang
- Department of Radiology, Center for NMR Research, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Lawrence I Sinoway
- Penn State Hershey Heart and Vascular Institute, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
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16
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Rockel C, Akbari A, Kumbhare DA, Noseworthy MD. Dynamic DTI (dDTI) shows differing temporal activation patterns in post-exercise skeletal muscles. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2016; 30:127-138. [PMID: 27624473 DOI: 10.1007/s10334-016-0587-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 08/09/2016] [Accepted: 08/22/2016] [Indexed: 12/20/2022]
Abstract
OBJECT To assess post-exercise recovery of human calf muscles using dynamic diffusion tensor imaging (dDTI). MATERIALS AND METHODS DTI data (6 directions, b = 0 and 400 s/mm2) were acquired every 35 s from seven healthy men using a 3T MRI, prior to (4 volumes) and immediately following exercise (13 volumes, ~7.5 min). Exercise consisted of 5-min in-bore repetitive dorsiflexion-eversion foot motion with 0.78 kg resistance. Diffusion tensors calculated at each time point produced maps of mean diffusivity (MD), fractional anisotropy (FA), radial diffusivity (RD), and signal at b = 0 s/mm2 (S0). Region-of-interest (ROI) analysis was performed on five calf muscles: tibialis anterior (ATIB), extensor digitorum longus (EDL) peroneus longus (PER), soleus (SOL), and lateral gastrocnemius (LG). RESULTS Active muscles (ATIB, EDL, PER) showed significantly elevated initial MD post-exercise, while predicted inactive muscles (SOL, LG) did not (p < 0.0001). The EDL showed a greater initial increase in MD (1.90 × 10-4mm2/s) than ATIB (1.03 × 10-4mm2/s) or PER (8.79 × 10-5 mm2/s) (p = 7.40 × 10-4), and remained significantly elevated across more time points than ATIB or PER. Significant increases were observed in post-exercise EDL S0 relative to other muscles across the majority of time points (p < 0.01 to p < 0.001). CONCLUSIONS dDTI can be used to differentiate exercise-induced changes between muscles. These differences are suggested to be related to differences in fiber composition.
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Affiliation(s)
- Conrad Rockel
- McMaster School of Biomedical Engineering, McMaster University, ETB-406 1280 Main St. West, Hamilton, ON, L8S 4K1, Canada.,Imaging Research Centre, St. Joseph's Healthcare, Hamilton, ON, Canada
| | - Alireza Akbari
- McMaster School of Biomedical Engineering, McMaster University, ETB-406 1280 Main St. West, Hamilton, ON, L8S 4K1, Canada.,Imaging Research Centre, St. Joseph's Healthcare, Hamilton, ON, Canada
| | - Dinesh A Kumbhare
- McMaster School of Biomedical Engineering, McMaster University, ETB-406 1280 Main St. West, Hamilton, ON, L8S 4K1, Canada.,Division of Physical Medicine and Rehabilitation, Department of Medicine, University of Toronto, Toronto, ON, Canada
| | - Michael D Noseworthy
- McMaster School of Biomedical Engineering, McMaster University, ETB-406 1280 Main St. West, Hamilton, ON, L8S 4K1, Canada. .,Imaging Research Centre, St. Joseph's Healthcare, Hamilton, ON, Canada. .,Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, ON, Canada. .,Department of Radiology, McMaster University, Hamilton, ON, Canada. .,Department of Electrical and Computer Engineering, McMaster University, Hamilton, ON, Canada.
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17
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Fouré A, Duhamel G, Vilmen C, Bendahan D, Jubeau M, Gondin J. Fast measurement of the quadriceps femoris muscle transverse relaxation time at high magnetic field using segmented echo-planar imaging. J Magn Reson Imaging 2016; 45:356-368. [DOI: 10.1002/jmri.25355] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 06/09/2016] [Indexed: 11/06/2022] Open
Affiliation(s)
- Alexandre Fouré
- Aix-Marseille Université, CNRS, CRMBM UMR; 7339 Marseille France
| | | | | | - David Bendahan
- Aix-Marseille Université, CNRS, CRMBM UMR; 7339 Marseille France
| | - Marc Jubeau
- Aix-Marseille Université, CNRS, CRMBM UMR; 7339 Marseille France
- Université de Nantes, Laboratoire “Motricité, Interactions, Performance,”; Nantes France
| | - Julien Gondin
- Aix-Marseille Université, CNRS, CRMBM UMR; 7339 Marseille France
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18
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Takahashi M, Yamaguchi S, Fujii T, Watanabe M, Hattori Y. Contribution of each masticatory muscle to the bite force determined by MRI using a novel metal-free bite force gauge and an index of total muscle activity. J Magn Reson Imaging 2016; 44:804-13. [PMID: 26970439 DOI: 10.1002/jmri.25223] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 02/22/2016] [Indexed: 02/03/2023] Open
Abstract
PURPOSE To develop a metal-free bite force gauge that can monitor the bite force in a strong magnetic field and to analyze the correlations between bite-force and total T2 shift of the mastication muscles. MATERIALS AND METHODS The gauge used a micro-pressure sensor made of optical fiber. Ten subjects performed a 60-s isometric bite task at 40% of maximum clenching in various occlusal support conditions (intact dentition, right molar loss, or left molar loss). Spin-echo images were taken with a 1.5 Tesla scanner before and immediately after the task to correlate the bite force with the mean voxel count, mean shift in transverse relaxation time (ΔT2), and total T2 shift of each masticatory muscle. RESULTS Measurements of total T2 shift identified significant correlations between the bite force and activities of the superficial layer of the bilateral masseter muscle, regardless of the occlusion condition (intact dentition: left, P = 0.007 and right, P < 0.001; right molar loss: left, P = 0.02 and right, P = 0.021; and left molar loss: left, P = 0.022 and right, P = 0.049). In contrast, significant correlations were not detected between the bite force and mean ΔT2 (intact dentition: left, P = 0.102 and right, P = 0.053; right molar loss: left, P = 0.393 and right, P = 0.868; and left molar loss: left, P = 0.531 and right, P = 0.92). CONCLUSION Measurement of total T2 shift using a metal-free bite force gauge is a more sensitive index of individual muscle activity than mean ΔT2 during a bite task. J. MAGN. RESON. IMAGING 2016;44:804-813.
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Affiliation(s)
- Minoru Takahashi
- Division of Aging and Geriatric Dentistry, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Satoshi Yamaguchi
- Division of Aging and Geriatric Dentistry, Tohoku University Graduate School of Dentistry, Sendai, Japan.
| | - Tsuyoshi Fujii
- Division of Aging and Geriatric Dentistry, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Makoto Watanabe
- Division of Aging and Geriatric Dentistry, Tohoku University Graduate School of Dentistry, Sendai, Japan.,Kansei Fukushi Research Center, Tohoku Fukushi University, Sendai, Japan
| | - Yoshinori Hattori
- Division of Aging and Geriatric Dentistry, Tohoku University Graduate School of Dentistry, Sendai, Japan
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19
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Hammon M, Grossmann S, Linz P, Kopp C, Dahlmann A, Janka R, Cavallaro A, Uder M, Titze J. 3 Tesla (23)Na magnetic resonance imaging during aerobic and anaerobic exercise. Acad Radiol 2015; 22:1181-90. [PMID: 26152501 DOI: 10.1016/j.acra.2015.06.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 05/28/2015] [Accepted: 06/03/2015] [Indexed: 11/19/2022]
Abstract
RATIONALE AND OBJECTIVES The aim of the work described here was to determine the feasibility of monitoring Na(+) concentration and distribution in muscle/skin during aerobic/anaerobic exercise with (23)Na magnetic resonance imaging (MRI). MATERIALS AND METHODS The Na(+) concentration and water content of muscle/skin of the left lower leg of six healthy subjects (mean age, 26 years; range, 22-30 years; three men and three women) were assessed before and after aerobic/anaerobic cycle ergometry and during recovery with 3-T (23)Na/(1)H MRI. (23)Na MRI was performed with a custom-made knee coil. A gradient echo sequence with an acquisition time of 3.25 minutes, echo time of 2.07 ms, repetition time of 100 ms, and spatial resolution of 3 × 3 × 30 mm(3) was applied. Phantoms with increasing sodium concentration served for quantification via linear extrapolation. Blood values were determined by blood gas analysis. RESULTS The concentration of Na(+) significantly increased during anaerobic exercise in all muscle compartments except the medial gastrocnemius muscle, whereas no significant change was observed in most muscle compartments during aerobic exercise (only the soleus muscle exhibited a significant increase in Na(+) concentration during aerobic exercise: 1.6 ± 1.5 mmol/kg, 4.5%, P = .046). During anaerobic exercise, the mean Na(+) concentration of the triceps surae and the whole leg increased by 9.0% (3.1 ± 2.1 mmol/kg, P = .016) and 6.5% (2.2 ± 1.3 mmol/kg, P < .01). MRI revealed a water-independent increase in Na(+) concentration in most muscle compartments during anaerobic exercise. Na(+) concentration significantly decreased during recovery after anaerobic and aerobic exercise in all muscle compartments except the soleus. The Na(+) concentration of the skin did not significantly change during anaerobic/aerobic exercise. CONCLUSIONS Sodium(23) MRI allows reliable and noninvasive visualization and quantification of Na(+) concentration and distribution in muscle and skin during exercise. (23)Na MRI can be used to gain new insights into Na(+) homeostasis, presumably leading to better comprehension of pathophysiology.
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Affiliation(s)
- Matthias Hammon
- Department of Radiology, University Hospital Erlangen, Maximiliansplatz 1, Erlangen 91054, Germany.
| | - Susan Grossmann
- Department of Radiology, University Hospital Erlangen, Maximiliansplatz 1, Erlangen 91054, Germany
| | - Peter Linz
- Department of Nephrology and Hypertension, University Hospital Erlangen, Erlangen, Germany
| | - Christoph Kopp
- Department of Nephrology and Hypertension, University Hospital Erlangen, Erlangen, Germany
| | - Anke Dahlmann
- Department of Nephrology and Hypertension, University Hospital Erlangen, Erlangen, Germany
| | - Rolf Janka
- Department of Radiology, University Hospital Erlangen, Maximiliansplatz 1, Erlangen 91054, Germany
| | - Alexander Cavallaro
- Department of Radiology, University Hospital Erlangen, Maximiliansplatz 1, Erlangen 91054, Germany
| | - Michael Uder
- Department of Radiology, University Hospital Erlangen, Maximiliansplatz 1, Erlangen 91054, Germany
| | - Jens Titze
- Department of Medicine, Vanderbilt University, Nashville, Tennessee
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20
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Varghese J, Scandling D, Joshi R, Aneja A, Craft J, Raman SV, Rajagopalan S, Simonetti OP, Mihai G. Rapid assessment of quantitative T1, T2 and T2* in lower extremity muscles in response to maximal treadmill exercise. NMR IN BIOMEDICINE 2015; 28:998-1008. [PMID: 26123219 PMCID: PMC4524289 DOI: 10.1002/nbm.3332] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 03/12/2015] [Accepted: 05/04/2015] [Indexed: 05/20/2023]
Abstract
MRI provides a non-invasive diagnostic platform to quantify the physical and physiological attributes of skeletal muscle at rest and in response to exercise. MR relaxation parameters (T1, T2 and T2*) are characteristic of tissue composition and metabolic properties. With the recent advent of quantitative techniques that allow rapid acquisition of T1, T2 and T2* maps, we posited that an integrated treadmill exercise-quantitative relaxometry paradigm can rapidly characterize exercise-induced changes in skeletal muscle relaxation parameters. Accordingly, we investigated the rest/recovery kinetics of T1, T2 and T2* in response to treadmill exercise in the anterior tibialis, soleus and gastrocnemius muscles of healthy volunteers, and the relationship of these parameters to age and gender. Thirty healthy volunteers (50.3 ± 16.6 years) performed the Bruce treadmill exercise protocol to maximal exhaustion. Relaxometric maps were sequentially acquired at baseline and for approximately 44 minutes post-exercise. Our results show that T1, T2 and T2* are significantly and differentially increased immediately post-exercise among the leg muscle groups, and these values recover to near baseline within 30-44 minutes. Our results demonstrate the potential to characterize the kinetics of relaxation parameters with quantitative mapping and upright exercise, providing normative values and some clarity on the impact of age and gender.
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Affiliation(s)
- Juliet Varghese
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, USA
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH, USA
| | - Debbie Scandling
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Rohit Joshi
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Ashish Aneja
- Department of Cardiology, MetroHealth Medical Center, Cleveland, OH, USA
| | - Jason Craft
- Department of Cardiology, Advocate Christ Medical Center, Oak Lawn, IL, USA
| | - Subha V. Raman
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, USA
- Division of Cardiovascular Medicine, Department of Internal Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Sanjay Rajagopalan
- Division of Cardiovascular Medicine, University of Maryland, Baltimore, MD, USA
| | - Orlando P. Simonetti
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, USA
- Division of Cardiovascular Medicine, Department of Internal Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, USA
- Department of Radiology, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Georgeta Mihai
- Department of Radiology, The Ohio State University Wexner Medical Center, Columbus, OH, USA
- Department of Radiology, Beth Israel Deaconess Medical Center, Boston, MA, USA
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21
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Dibb R, Qi Y, Liu C. Magnetic susceptibility anisotropy of myocardium imaged by cardiovascular magnetic resonance reflects the anisotropy of myocardial filament α-helix polypeptide bonds. J Cardiovasc Magn Reson 2015; 17:60. [PMID: 26177899 PMCID: PMC4504227 DOI: 10.1186/s12968-015-0159-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 06/23/2015] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND A key component of evaluating myocardial tissue function is the assessment of myofiber organization and structure. Studies suggest that striated muscle fibers are magnetically anisotropic, which, if measurable in the heart, may provide a tool to assess myocardial microstructure and function. METHODS To determine whether this weak anisotropy is observable and spatially quantifiable with cardiovascular magnetic resonance (CMR), both gradient-echo and diffusion-weighted data were collected from intact mouse heart specimens at 9.4 Tesla. Susceptibility anisotropy was experimentally calculated using a voxelwise analysis of myocardial tissue susceptibility as a function of myofiber angle. A myocardial tissue simulation was developed to evaluate the role of the known diamagnetic anisotropy of the peptide bond in the observed susceptibility contrast. RESULTS The CMR data revealed that myocardial tissue fibers that were parallel and perpendicular to the magnetic field direction appeared relatively paramagnetic and diamagnetic, respectively. A linear relationship was found between the magnetic susceptibility of the myocardial tissue and the squared sine of the myofiber angle with respect to the field direction. The multi-filament model simulation yielded susceptibility anisotropy values that reflected those found in the experimental data, and were consistent that this anisotropy decreased as the echo time increased. CONCLUSIONS Though other sources of susceptibility anisotropy in myocardium may exist, the arrangement of peptide bonds in the myofilaments is a significant, and likely the most dominant source of susceptibility anisotropy. This anisotropy can be further exploited to probe the integrity and organization of myofibers in both healthy and diseased heart tissue.
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Affiliation(s)
- Russell Dibb
- Center for In Vivo Microscopy, Duke University Medical Center, Box 3302, Durham, NC, 27710, USA.
- Biomedical Engineering, Duke University Medical Center, Campus Box 90281, Durham, NC, 27708, USA.
| | - Yi Qi
- Center for In Vivo Microscopy, Duke University Medical Center, Box 3302, Durham, NC, 27710, USA.
| | - Chunlei Liu
- Brain Imaging & Analysis Center, Duke University Medical Center, Box 3918, Durham, NC, 27710, USA.
- Radiology, Duke University Medical Center, Box 3808, Durham, NC, 27710, USA.
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Buck AKW, Elder CP, Donahue MJ, Damon BM. Matching of postcontraction perfusion to oxygen consumption across submaximal contraction intensities in exercising humans. J Appl Physiol (1985) 2015; 119:280-9. [PMID: 26066829 DOI: 10.1152/japplphysiol.01027.2014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 06/08/2015] [Indexed: 12/23/2022] Open
Abstract
Studying the magnitude and kinetics of blood flow, oxygen extraction, and oxygen consumption at exercise onset and during the recovery from exercise can lead to insights into both the normal control of metabolism and blood flow and the disturbances to these processes in metabolic and cardiovascular diseases. The purpose of this study was to examine the on- and off-kinetics for oxygen delivery, extraction, and consumption as functions of submaximal contraction intensity. Eight healthy subjects performed four 1-min isometric dorsiflexion contractions, with two at 20% MVC and two at 40% MVC. During one contraction at each intensity, relative perfusion changes were measured by using arterial spin labeling, and the deoxyhemoglobin percentage (%HHb) was estimated using the spin- and gradient-echo sequence and a previously published empirical calibration. For the whole group, the mean perfusion did not increase during contraction. The %HHb increased from ∼28 to 38% during contractions of each intensity, with kinetics well described by an exponential function and mean response times (MRTs) of 22.7 and 21.6 s for 20 and 40% MVC, respectively. Following contraction, perfusion increased ∼2.5-fold. The %HHb, oxygen consumption, and perfusion returned to precontraction levels with MRTs of 27.5, 46.4, and 50.0 s, respectively (20% MVC), and 29.2, 75.3, and 86.0 s, respectively (40% MVC). These data demonstrate in human subjects the varied recovery rates of perfusion and oxygen consumption, along with the similar rates of %HHb recovery, across these exercise intensities.
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Affiliation(s)
- Amanda K W Buck
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee; Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee; Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee
| | - Christopher P Elder
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee
| | - Manus J Donahue
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee; Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee; Department of Psychiatry, Vanderbilt University, Nashville, Tennessee; Department of Neurology, Vanderbilt University, Nashville, Tennessee; Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee; and
| | - Bruce M Damon
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee; Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee; Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee; Department of Molecular Physiology and Biophysics Vanderbilt University, Nashville, Tennessee
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JUBEAU MARC, LE FUR YANN, DUHAMEL GUILLAUME, WEGRZYK JENNIFER, CONFORT-GOUNY SYLVIANE, VILMEN CHRISTOPHE, COZZONE PATRICKJ, MATTEI JEANPIERRE, BENDAHAN DAVID, GONDIN JULIEN. Localized Metabolic and T2 Changes Induced by Voluntary and Evoked Contractions. Med Sci Sports Exerc 2015; 47:921-30. [DOI: 10.1249/mss.0000000000000491] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Hiepe P, Gussew A, Rzanny R, Kurz E, Anders C, Walther M, Scholle HC, Reichenbach JR. Age-related structural and functional changes of low back muscles. Exp Gerontol 2015; 65:23-34. [PMID: 25735850 DOI: 10.1016/j.exger.2015.02.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 02/26/2015] [Accepted: 02/27/2015] [Indexed: 01/15/2023]
Abstract
During aging declining maximum force capacity with more or less unchanged fatigability is observed with the underlying mechanisms still not fully understood. Therefore, we compared morphology and function of skeletal muscles between different age groups. Changes in high-energy phosphate turnover (PCr, Pi and pH) and muscle functional MRI (mfMRI) parameters, including proton transverse relaxation time (T2), diffusion (D) and vascular volume fraction (f), were investigated in moderately exercised low back muscles of young and late-middle-aged healthy subjects with (31)P-MR spectroscopy, T2- and diffusion-weighted MRI at 3T. In addition, T1-weighted MRI data were acquired to determine muscle cross-sectional areas (CSA) and to assess fat infiltration into muscle tissue. Except for pH, both age groups showed similar load-induced MR changes and rates of perceived exertion (RPE), which indicates comparable behavior of muscle activation at moderate loads. Changes of mfMRI parameters were significantly associated with RPE in both cohorts. Age-related differences were observed, with lower pH and higher Pi/ATP ratios as well as lower D and f values in the late-middle-aged subjects. These findings are ascribed to age-related changes of fiber type composition, fiber size and vascularity. Interestingly, post exercise f was negatively associated with fat infiltration with the latter being significantly higher in late-middle-aged subjects. CSA of low back muscles remained unchanged, while CSA of inner back muscle as well as mean T2 at rest were associated with maximum force capacity. Overall, applying the proposed MR approach provides evidence of age-related changes in several muscle tissue characteristics and gives new insights into the physiological processes that take place during aging.
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Affiliation(s)
- Patrick Hiepe
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena, Germany.
| | - Alexander Gussew
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena, Germany
| | - Reinhard Rzanny
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena, Germany
| | - Eduard Kurz
- Department for Trauma-, Hand- and Reconstructive Surgery, Division of Motor Research, Pathophysiology and Biomechanics, Jena University Hospital - Friedrich Schiller University Jena, Germany
| | - Christoph Anders
- Department for Trauma-, Hand- and Reconstructive Surgery, Division of Motor Research, Pathophysiology and Biomechanics, Jena University Hospital - Friedrich Schiller University Jena, Germany
| | - Mario Walther
- Institute of Medical Statistics, Computer Sciences and Documentation (IMSID), Jena University Hospital - Friedrich Schiller University Jena, Germany
| | - Hans-Christoph Scholle
- Department for Trauma-, Hand- and Reconstructive Surgery, Division of Motor Research, Pathophysiology and Biomechanics, Jena University Hospital - Friedrich Schiller University Jena, Germany
| | - Jürgen R Reichenbach
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital - Friedrich Schiller University Jena, Germany
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Li K, Dortch RD, Welch EB, Bryant ND, Buck AKW, Towse TF, Gochberg DF, Does MD, Damon BM, Park JH. Multi-parametric MRI characterization of healthy human thigh muscles at 3.0 T - relaxation, magnetization transfer, fat/water, and diffusion tensor imaging. NMR IN BIOMEDICINE 2014; 27:1070-84. [PMID: 25066274 PMCID: PMC4153695 DOI: 10.1002/nbm.3159] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Revised: 05/28/2014] [Accepted: 06/01/2014] [Indexed: 05/11/2023]
Abstract
Muscle diseases commonly have clinical presentations of inflammation, fat infiltration, fibrosis, and atrophy. However, the results of existing laboratory tests and clinical presentations are not well correlated. Advanced quantitative MRI techniques may allow the assessment of myo-pathological changes in a sensitive and objective manner. To progress towards this goal, an array of quantitative MRI protocols was implemented for human thigh muscles; their reproducibility was assessed; and the statistical relationships among parameters were determined. These quantitative methods included fat/water imaging, multiple spin-echo T2 imaging (with and without fat signal suppression, FS), selective inversion recovery for T1 and quantitative magnetization transfer (qMT) imaging (with and without FS), and diffusion tensor imaging. Data were acquired at 3.0 T from nine healthy subjects. To assess the repeatability of each method, the subjects were re-imaged an average of 35 days later. Pre-testing lifestyle restrictions were applied to standardize physiological conditions across scans. Strong between-day intra-class correlations were observed in all quantitative indices except for the macromolecular-to-free water pool size ratio (PSR) with FS, a metric derived from qMT data. Two-way analysis of variance revealed no significant between-day differences in the mean values for any parameter estimate. The repeatability was further assessed with Bland-Altman plots, and low repeatability coefficients were obtained for all parameters. Among-muscle differences in the quantitative MRI indices and inter-class correlations among the parameters were identified. There were inverse relationships between fractional anisotropy (FA) and the second eigenvalue, the third eigenvalue, and the standard deviation of the first eigenvector. The FA was positively related to the PSR, while the other diffusion indices were inversely related to the PSR. These findings support the use of these T1 , T2 , fat/water, and DTI protocols for characterizing skeletal muscle using MRI. Moreover, the data support the existence of a common biophysical mechanism, water content, as a source of variation in these parameters.
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Affiliation(s)
- Ke Li
- Institute of Imaging Science, Vanderbilt University, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, USA
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26
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Hiepe P, Gussew A, Rzanny R, Anders C, Walther M, Scholle HC, Reichenbach JR. Interrelations of muscle functional MRI, diffusion-weighted MRI and (31) P-MRS in exercised lower back muscles. NMR IN BIOMEDICINE 2014; 27:958-970. [PMID: 24953438 DOI: 10.1002/nbm.3141] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 04/17/2014] [Accepted: 04/29/2014] [Indexed: 06/03/2023]
Abstract
Exercise-induced changes of transverse proton relaxation time (T2 ), tissue perfusion and metabolic turnover were investigated in the lower back muscles of volunteers by applying muscle functional MRI (mfMRI) and diffusion-weighted imaging (DWI) before and after as well as dynamic (31) P-MRS during the exercise. Inner (M. multifidus, MF) and outer lower back muscles (M. erector spinae, ES) were examined in 14 healthy young men performing a sustained isometric trunk-extension. Significant phosphocreatine (PCr) depletions ranging from 30% (ES) to 34% (MF) and Pi accumulations between 95% (left ES) and 120%-140% (MF muscles and right ES) were observed during the exercise, which were accompanied by significantly decreased pH values in all muscles (∆pH ≈ -0.05). Baseline T2 values were similar across all investigated muscles (approximately 27 ms at 3 T), but revealed right-left asymmetric increases (T2 ,inc ) after the exercise (right ES/MF: T2 ,inc = 11.8/9.7%; left ES/MF: T2 ,inc = 4.6/8.9%). Analyzed muscles also showed load-induced increases in molecular diffusion D (p = .007) and perfusion fraction f (p = .002). The latter parameter was significantly higher in the MF than in the ES muscles both at rest and post exercise. Changes in PCr (p = .03), diffusion (p < .01) and perfusion (p = .03) were strongly associated with T2,inc , and linear mixed model analysis revealed that changes in PCr and perfusion both affect T2,inc (p < .001). These findings support previous assumptions that T2 changes are not only an intra-cellular phenomenon resulting from metabolic stress but are also affected by increased perfusion in loaded muscles.
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Affiliation(s)
- Patrick Hiepe
- Medical Physics Group, Institute of Diagnostic and Interventional Radiology I, Center of Radiology, Jena University Hospital - Friedrich Schiller University, Jena, Germany
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Bryant ND, Li K, Does MD, Barnes S, Gochberg DF, Yankeelov TE, Park JH, Damon BM. Multi-parametric MRI characterization of inflammation in murine skeletal muscle. NMR IN BIOMEDICINE 2014; 27:716-25. [PMID: 24777935 PMCID: PMC4134016 DOI: 10.1002/nbm.3113] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2013] [Revised: 02/10/2014] [Accepted: 03/13/2014] [Indexed: 05/15/2023]
Abstract
Myopathies often display a common set of complex pathologies that include muscle weakness, inflammation, compromised membrane integrity, fat deposition, and fibrosis. Multi-parametric, quantitative, non-invasive imaging approaches may be able to resolve these individual pathological components. The goal of this study was to use multi-parametric MRI to investigate inflammation as an isolated pathological feature. Proton relaxation, diffusion tensor imaging (DTI), quantitative magnetization transfer (qMT-MRI), and dynamic contrast enhanced (DCE-MRI) parameters were calculated from data acquired in a single imaging session conducted 6-8 hours following the injection of λ-carrageenan, a local inflammatory agent. T2 increased in the inflamed muscle and transitioned to bi-exponential behavior. In diffusion measurements, all three eigenvalues and the apparent diffusion coefficient increased, but λ3 had the largest relative change. Analysis of the qMT data revealed that the T1 of the free pool and the observed T1 both increased in the inflamed tissue, while the ratio of exchanging spins in the solid pool to those in the free water pool (the pool size ratio) significantly decreased. DCE-MRI data also supported observations of an increase in extracellular volume. These findings enriched the understanding of the relation between multiple quantitative MRI parameters and an isolated inflammatory pathology, and may potentially be employed for other single or complex myopathy models.
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Affiliation(s)
- Nathan D Bryant
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, USA
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Schmid AI, Schewzow K, Fiedler GB, Goluch S, Laistler E, Wolzt M, Moser E, Meyerspeer M. Exercising calf muscle T₂∗ changes correlate with pH, PCr recovery and maximum oxidative phosphorylation. NMR IN BIOMEDICINE 2014; 27:553-60. [PMID: 24610788 PMCID: PMC4260669 DOI: 10.1002/nbm.3092] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 01/13/2014] [Accepted: 01/17/2014] [Indexed: 05/12/2023]
Abstract
Skeletal muscle metabolism is impaired in disorders like diabetes mellitus or peripheral vascular disease. The skeletal muscle echo planar imaging (EPI) signal (S(EPI) ) and its relation to energy metabolism are still debated. Localised ³¹P MRS and S(EPI) data from gastrocnemius medialis of 19 healthy subjects were combined in one scanning session to study direct relationships between phosphocreatine (PCr), pH kinetics and parameters of T₂∗ time courses. Dynamic spectroscopy (semi-LASER) and EPI were performed immediately before, during and after 5 min of plantar flexions. Data were acquired in a 7 T MR scanner equipped with a custom-built ergometer and a dedicated ³¹P/¹H radio frequency (RF) coil array. Using a form-fitted multi-channel ³¹P/¹H coil array resulted in high signal-to-noise ratio (SNR). PCr and pH in the gastrocnemius medialis muscle were quantified from each ³¹P spectrum, acquired every 6 s. During exercise, SEPI (t) was found to be a linear function of tissue pH(t) (cross-correlation r = -0.85 ± 0.07). Strong Pearson's correlations were observed between post exercise time-to-peak (TTP) of SEPI and (a) the time constant of PCr recovery τPCr recovery (r = 0.89, p < 10⁻⁶), (b) maximum oxidative phosphorylation using the linear model, Q(max, lin) (r = 0.65, p = 0.002), the adenosine-diphosphate-driven model, Q(max,ADP) (r = 0.73, p = 0.0002) and (c) end exercise pH (r = 0.60, p = 0.005). Based on combined accurately localised ³¹P MRS and T₂∗ weighted MRI, both with high temporal resolution, strong correlations of the skeletal muscle SEPI during exercise and tissue pH time courses and of post exercise SEPI and parameters of energy metabolism were observed. In conclusion, a tight coupling between skeletal muscle metabolic activity and tissue T₂∗ signal weighting, probably induced by osmotically driven water shift, exists and can be measured non-invasively, using NMR at 7 T.
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Affiliation(s)
- Albrecht Ingo Schmid
- Center for Medical Physics and Biomedical Engineering, Medical University of ViennaWähringer Gürtel 18-20, 1090, Wien, Austria
- MR Centre of Excellence, Medical University of ViennaLazarettgasee 14, 1090, Wien, Austria
| | - Kiril Schewzow
- Center for Medical Physics and Biomedical Engineering, Medical University of ViennaWähringer Gürtel 18-20, 1090, Wien, Austria
- MR Centre of Excellence, Medical University of ViennaLazarettgasee 14, 1090, Wien, Austria
| | - Georg Bernd Fiedler
- Center for Medical Physics and Biomedical Engineering, Medical University of ViennaWähringer Gürtel 18-20, 1090, Wien, Austria
- MR Centre of Excellence, Medical University of ViennaLazarettgasee 14, 1090, Wien, Austria
| | - Sigrun Goluch
- Center for Medical Physics and Biomedical Engineering, Medical University of ViennaWähringer Gürtel 18-20, 1090, Wien, Austria
- MR Centre of Excellence, Medical University of ViennaLazarettgasee 14, 1090, Wien, Austria
| | - Elmar Laistler
- Center for Medical Physics and Biomedical Engineering, Medical University of ViennaWähringer Gürtel 18-20, 1090, Wien, Austria
- MR Centre of Excellence, Medical University of ViennaLazarettgasee 14, 1090, Wien, Austria
| | - Michael Wolzt
- Department of Clinical Pharmacology, Medical University of ViennaWähringer Gürtel 18-20, 1090, Wien, Austria
| | - Ewald Moser
- Center for Medical Physics and Biomedical Engineering, Medical University of ViennaWähringer Gürtel 18-20, 1090, Wien, Austria
- MR Centre of Excellence, Medical University of ViennaLazarettgasee 14, 1090, Wien, Austria
| | - Martin Meyerspeer
- Center for Medical Physics and Biomedical Engineering, Medical University of ViennaWähringer Gürtel 18-20, 1090, Wien, Austria
- MR Centre of Excellence, Medical University of ViennaLazarettgasee 14, 1090, Wien, Austria
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29
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Schewzow K, Fiedler GB, Meyerspeer M, Goluch S, Laistler E, Wolzt M, Moser E, Schmid AI. Dynamic ASL and T2-weighted MRI in exercising calf muscle at 7 T: a feasibility study. Magn Reson Med 2014; 73:1190-5. [PMID: 24752959 DOI: 10.1002/mrm.25242] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Revised: 03/06/2014] [Accepted: 03/16/2014] [Indexed: 11/10/2022]
Abstract
PURPOSE The aim of this study was to develop a measurement protocol for noninvasive simultaneous perfusion quantification and T2 *-weighted MRI acquisition in the exercising calf muscle at 7 Tesla. METHODS Using a nonmagnetic ergometer and a dedicated in-house built calf coil array, dynamic pulsed arterial spin labeling (PASL) measurements with a temporal resolution of 12 s were performed before, during, and after plantar flexion exercise in 16 healthy volunteers. RESULTS Postexercise peak perfusion in gastrocnemius muscle (GAS) was 27 ± 16 ml/100g/min, whereas in soleus (SOL) and tibialis anterior (TA) muscles it remained at baseline levels. T2 *-weighted and ASL time courses in GAS showed comparable times to peak of 161 ± 72 s and 167 ± 115 s, respectively. The T2 *-weighted signal in the GAS showed a minimum during exercise (88 ± 6 % of the baseline signal) and a peak during the recovery (122 ± 9%), whereas in all other muscles only a signal decrease was observed (minimum 91 ± 6% in SOL; 87 ± 8% in TA). CONCLUSION We demonstrate the feasibility of dynamic perfusion quantification in skeletal muscle at 7 Tesla using PASL. This may help to better investigate the physiological processes in the skeletal muscle and also in diseases such as diabetes mellitus and peripheral arterial disease.
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Affiliation(s)
- Kiril Schewzow
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria; MR Centre of Excellence, Medical University of Vienna, Vienna, Austria
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30
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Jacobi B, Bongartz G, Partovi S, Schulte AC, Aschwanden M, Lumsden AB, Davies MG, Loebe M, Noon GP, Karimi S, Lyo JK, Staub D, Huegli RW, Bilecen D. Skeletal muscle BOLD MRI: from underlying physiological concepts to its usefulness in clinical conditions. J Magn Reson Imaging 2012; 35:1253-65. [PMID: 22588992 DOI: 10.1002/jmri.23536] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Blood oxygenation-level dependent (BOLD) MRI has gained particular attention in functional brain imaging studies, where it can be used to localize areas of brain activation with high temporal resolution. To a higher degree than in the brain, skeletal muscles show extensive but transient alterations of blood flow between resting and activation state. Thus, there has been interest in the application of the BOLD effect in studying the physiology of skeletal muscles (healthy and diseased) and its possible application to clinical practice. This review outlines the potential of skeletal muscle BOLD MRI as a diagnostic tool for the evaluation of physiological and pathological alterations in the peripheral limb perfusion, such as in peripheral arterial occlusive disease. Moreover, current knowledge is summarized regarding the complex mechanisms eliciting BOLD effect in skeletal muscle. We describe technical fundaments of the procedure that should be taken into account when performing skeletal muscle BOLD MRI, including the most often applied paradigms to provoke BOLD signal changes and key parameters of the resulting time courses. Possible confounding effects in muscle BOLD imaging studies, like age, muscle fiber type, training state, and drug effects are also reviewed in detail.
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Affiliation(s)
- Bjoern Jacobi
- Department of Radiology, University Hospital Bruderholz, Bruderholz, Basel, Switzerland
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31
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Schraml C, Schwenzer NF, Martirosian P, Claussen CD, Schick F. Temporal course of perfusion in human masseter muscle during isometric contraction assessed by arterial spin labeling at 3T. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2011; 24:201-9. [DOI: 10.1007/s10334-011-0254-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Revised: 04/19/2011] [Accepted: 04/19/2011] [Indexed: 11/29/2022]
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Elder CP, Cook RN, Chance MA, Copenhaver EA, Damon BM. Image-based calculation of perfusion and oxyhemoglobin saturation in skeletal muscle during submaximal isometric contractions. Magn Reson Med 2011; 64:852-61. [PMID: 20806379 DOI: 10.1002/mrm.22475] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The relative oxygen saturation of hemoglobin and the rate of perfusion are important physiological quantities, particularly in organs such as skeletal muscle, in which oxygen delivery and use are tightly coupled. The purpose of this study was to demonstrate the image-based calculation of the relative oxygen saturation of hemoglobin and quantification of perfusion in skeletal muscle during isometric contractions. This was accomplished by establishing an empirical relationship between the rate of radiofrequency-reversible dephasing and near-infrared spectroscopy-observed oxyhemoglobin saturation (relative oxygen saturation of hemoglobin) under conditions of arterial occlusion and constant blood volume. A calibration curve was generated and used to calculate the relative oxygen saturation of hemoglobin from radiofrequency-reversible dephasing changes measured during contraction. Twelve young healthy subjects underwent 300 s of arterial occlusion and performed isometric contractions of the dorsiflexors at 30% of maximal contraction for 120 s. Muscle perfusion was quantified during contraction by arterial spin labeling and measures of muscle T(1). Comparisons between the relative oxygen saturation of hemoglobin values predicted from radiofrequency-reversible dephasing and that measured by near-infrared spectroscopy revealed no differences between methods (P = 0.760). Muscle perfusion reached a value of 34.7 mL 100 g(-1) min(-1) during contraction. These measurements hold future promise in measuring muscle oxygen consumption in healthy and diseased skeletal muscle.
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Affiliation(s)
- Christopher P Elder
- Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee 37232-2310, USA
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33
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Sanchez OA, Copenhaver EA, Elder CP, Damon BM. Absence of a significant extravascular contribution to the skeletal muscle BOLD effect at 3 T. Magn Reson Med 2011; 64:527-35. [PMID: 20665796 DOI: 10.1002/mrm.22449] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Blood oxygenation level dependent (BOLD) contrast in skeletal may reflect the contributions of both intravascular and extravascular relaxation effects. The purpose of this study was to determine the significance of the extravascular BOLD effect in skeletal muscle at 3 T. In experiments, R(2)* was measured before and during arterial occlusion under the following conditions: (1) the leg extended and rotated (to vary the capillary orientation with respect to the amplitude of static field) and (2) with the blood's signal nulled using a multiecho vascular space occupancy experiment. In the leg rotation protocol, 3 min of arterial occlusion decreased oxyhemoglobin saturation from 67% to 45% and increased R(2)* from 34.2 to 36.6 sec(-1), but there was no difference in the R(2)* response to occlusion between the extended and rotated positions. Numerical simulations of intra- and extravascular BOLD effects corresponding to these conditions predicted that the intravascular BOLD contribution to the R(2)* change was always > 50 times larger than the extravascular BOLD contribution. Blood signal nulling eliminated the change in R(2)* caused by arterial occlusion. These data indicate that under these experimental conditions, the contribution of the extravascular BOLD effect to skeletal muscle R(2)* was too small to be practically important.
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Affiliation(s)
- Otto A Sanchez
- Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee, USA
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Elder CP, Cook RN, Wilkens KL, Chance MA, Sanchez OA, Damon BM. A method for detecting the temporal sequence of muscle activation during cycling using MRI. J Appl Physiol (1985) 2010; 110:826-33. [PMID: 21164153 DOI: 10.1152/japplphysiol.00185.2010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Surface electromyography (EMG) can assess muscle recruitment patterns during cycling, but has limited applicability to studies of deep muscle recruitment and electrically stimulated contractions. We determined whether muscle recruitment timing could be inferred from MRI-measured transverse relaxation time constant (T(2)) changes and a cycle ergometer modified to vary power as a function of pedal angle. Six subjects performed 6 min of single-leg cycling under two conditions (E0°-230° and E90°-230°), which increased the power from 0°-230° and 90-230° of the pedal cycle, respectively. The difference condition produced a virtual power output from 0-180° (V0°-180°). Recruitment was assessed by integrating EMG over the pedal cycle (IEMG) and as the (post-pre) exercise T(2) change (ΔT(2)). For E0°-230°, the mean IEMG for vastus medialis and lateralis (VM/VL; 49.3 ± 3.9 mV·s; mean ± SE) was greater (P < 0.05) than that for E90°-230° (17.9 ± 1.9 mV·s); the corresponding ΔT(2) values were 8.7 ± 1.0 and 1.4 ± 0.5 ms (P < 0.05). For E0°-230° and E90°-230°, the IEMG values for biceps femoris/long head (BF(L)) were 37.7 ± 5.4 and 27.1 ± 5.6 mV·s (P > 0.05); the corresponding ΔT(2) values were 0.9 ± 0.9 and 1.5 ± 0.9 ms (P > 0.05). MRI data indicated activation of the semitendinosus and BF/short head for E0°-230° and E90°-230°. For V0°-180°, ΔT(2) was 7.2 ± 0.9 ms for VM/VL and -0.6 ± 0.6 ms for BF(L); IEMG was 31.5 ± 3.7 mV·s for VM/VL and 10.6 ± 7.0 mV·s for BF(L). MRI and EMG data indicate VM/VL activity from 0 to 180° and selected hamstring activity from 90 to 230°. Combining ΔT(2) measurements with variable loading allows the spatial and temporal patterns of recruitment during cycling to be inferred from MRI data.
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Affiliation(s)
- Christopher P Elder
- Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee, USA
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35
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Chang G, Wang L, Cárdenas-Blanco A, Schweitzer ME, Recht MP, Regatte RR. Biochemical and physiological MR imaging of skeletal muscle at 7 tesla and above. Semin Musculoskelet Radiol 2010; 14:269-78. [PMID: 20486034 DOI: 10.1055/s-0030-1253167] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Ultra-high field (UHF; >or=7 T) magnetic resonance imaging (MRI), with its greater signal-to-noise ratio, offers the potential for increased spatial resolution, faster scanning, and, above all, improved biochemical and physiological imaging of skeletal muscle. The increased spectral resolution and greater sensitivity to low-gamma nuclei available at UHF should allow techniques such as (1)H MR spectroscopy (MRS), (31)P MRS, and (23)Na MRI to be more easily implemented. Numerous technical challenges exist in the performance of UHF MRI, including changes in relaxation values, increased chemical shift and susceptibility artifact, radiofrequency (RF) coil design/B (1)(+) field inhomogeneity, and greater RF energy deposition. Nevertheless, the possibility of improved functional and metabolic imaging at UHF will likely drive research efforts in the near future to overcome these challenges and allow studies of human skeletal muscle physiology and pathophysiology to be possible at >or=7 T.
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Affiliation(s)
- Gregory Chang
- Department of Radiology, Center for Biomedical Imaging, New York University School of Medicine, New York, New York, 10016, USA.
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Chang G, Wang L, Schweitzer ME, Regatte RR. 3D 23Na MRI of human skeletal muscle at 7 Tesla: initial experience. Eur Radiol 2010; 20:2039-46. [PMID: 20309556 DOI: 10.1007/s00330-010-1761-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2009] [Revised: 01/31/2010] [Accepted: 02/12/2010] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To evaluate healthy skeletal muscle pre- and post-exercise via 7 T (23)Na MRI and muscle proton T(2) mapping, and to evaluate diabetic muscle pre- and post-exercise via 7 T (23)Na MRI. METHODS The calves of seven healthy subjects underwent imaging pre- and post-exercise via 7 T (23)Na MRI (3D fast low angle shot, TR/TE = 80 ms/0.160 ms, 4 mm x 4 mm x 4 mm) and 1 week later by (1)H MRI (multiple spin-echo sequence, TR/TE = 3,000 ms/15-90 ms). Four type 2 diabetics also participated in the (23)Na MRI protocol. Pre- and post-exercise sodium signal intensity (SI) and proton T(2) relaxation values were measured/calculated for soleus (S), gastrocnemius (G), and a control, tibialis anterior (TA). Two-tailed t tests were performed. RESULTS In S/G in healthy subjects post-exercise, sodium SI increased 8-13% (p < 0.03), then decreased (t(1/2) = 22 min), and (1)H T(2) values increased 12-17% (p < 0.03), then decreased (t(1/2 )= 12-15 min). In TA, no significant changes in sodium SI or (1)H T(2) values were seen (-2.4 to 1%, p > 0.17). In S/G in diabetics, sodium SI increased 10-11% (p < 0.04), then decreased (t(1/2) = 27-37 min) without significant change in the TA SI (-3.6%, p = 0.066). CONCLUSION It is feasible to evaluate skeletal muscle via 3D (23)Na MRI at 7 T. Post-exercise muscle (1)H T(2) values return to baseline more rapidly than sodium SI. Diabetics may demonstrate delayed muscle sodium SI recovery compared with healthy subjects.
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Affiliation(s)
- Gregory Chang
- Department of Radiology, NYU Langone Medical Center, Center for Biomedical Imaging/Hospital for Joint Diseases, New York, NY 10016, USA.
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Neves EB, Pino AV, de Almeida RMVR, de Souza MN. Knee bioelectric impedance assessment in healthy/with osteoarthritis subjects. Physiol Meas 2009; 31:207-19. [DOI: 10.1088/0967-3334/31/2/007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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T2*-Weighted and Arterial Spin Labeling MRI of Calf Muscles in Healthy Volunteers and Patients With Chronic Exertional Compartment Syndrome: Preliminary Experience. AJR Am J Roentgenol 2009; 193:W327-33. [DOI: 10.2214/ajr.08.1579] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Dortch RD, Yankeelov TE, Yue Z, Quarles CC, Gore JC, Does MD. Evidence of multiexponential T2 in rat glioblastoma. NMR IN BIOMEDICINE 2009; 22:609-18. [PMID: 19267385 PMCID: PMC4178926 DOI: 10.1002/nbm.1374] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The aim of this study was to characterize multiexponential T(2) (MET(2)) relaxation in a rat C6 glioblastoma tumor model. To do this, rats (n = 11) were inoculated with the C6 cells via stereotaxic injection into the brain. Ten days later, MET(2) measurements were performed in vivo using a single-slice, multi-echo spin-echo sequence at 7.0 T. Tumor signal was biexponential in eight animals with a short-lived T(2) component (T(2) = 20.7 +/- 5.4 ms across samples) representing 6.8 +/- 6.2% of the total signal and a long-lived T(2) component (T(2) = 76.4 +/- 9.3 ms) representing the remaining signal fraction. In contrast, signal from contralateral grey matter was consistently monoexponential (T(2) = 48.8 +/- 2.3 ms). Additional ex vivo studies (n = 3) and Monte Carlo simulations showed that the in vivo results were not significantly corrupted by partial volume averaging or noise. The underlying physiological origin of the observed MET(2) components is unknown; however, MET(2) analysis may hold promise as a non-invasive tool for characterizing tumor microenvironment in vivo on a sub-voxel scale.
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Affiliation(s)
- Richard D. Dortch
- Biomedical Engineering, Vanderbilt University, Nashville, TN, United States
- Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States
| | - Thomas E. Yankeelov
- Biomedical Engineering, Vanderbilt University, Nashville, TN, United States
- Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States
- Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States
- Physics and Astronomy, Vanderbilt University, Nashville, TN, United States
- Cancer Biology, Vanderbilt University, Nashville, TN, United States
| | - Zoe Yue
- Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States
| | - Christopher C. Quarles
- Biomedical Engineering, Vanderbilt University, Nashville, TN, United States
- Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States
- Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States
| | - John C. Gore
- Biomedical Engineering, Vanderbilt University, Nashville, TN, United States
- Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States
- Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States
- Physics and Astronomy, Vanderbilt University, Nashville, TN, United States
- Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, United States
| | - Mark D. Does
- Biomedical Engineering, Vanderbilt University, Nashville, TN, United States
- Institute of Imaging Science, Vanderbilt University, Nashville, TN, United States
- Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States
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Louie EA, Gochberg DF, Does MD, Damon BM. Transverse relaxation and magnetization transfer in skeletal muscle: effect of pH. Magn Reson Med 2009; 61:560-9. [PMID: 19097244 DOI: 10.1002/mrm.21847] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Exercise increases the intracellular T(2) (T(2,i)) of contracting muscles. The mechanism(s) for the T(2,i) increase have not been fully described, and may include increased intracellular free water and acidification. These changes may alter chemical exchange processes between intracellular free water and proteins. In this study, the hypotheses were tested that (a) pH changes T(2,i) by affecting the rate of magnetization transfer (MT) between free intracellular water and intracellular proteins, and (b) the magnitude of the T(2,i) effect depends on acquisition mode (localized or nonlocalized) and echo spacing. Frog gastrocnemius muscles were excised and their intracellular pH was either kept at physiological pH (7.0) or modified to model exercising muscle (pH 6.5). The intracellular transverse relaxation rate (R(2,i) = 1/T(2,i)) always decreased in the acidic muscles, but the changes were greater when measured using more rapid refocusing rates. The MT rate from the macromolecular proton pool to the free water proton pool, its reverse rate, and the spin-lattice relaxation rate of water decreased in acidic muscles. It is concluded that intracellular acidification alters the R(2,i) of muscle water in a refocusing rate-dependent manner, and that the R(2,i) changes are correlated with changes in the MT rate between macromolecules and free intracellular water.
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Affiliation(s)
- Elizabeth A Louie
- Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee 37232-2310, USA
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41
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Ababneh ZQ, Ababneh R, Maier SE, Winalski CS, Oshio K, Ababneh AM, Mulkern RV. On the correlation between T2 and tissue diffusion coefficients in exercised muscle: quantitative measurements at 3T within the tibialis anterior. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2008; 21:273-8. [DOI: 10.1007/s10334-008-0120-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2008] [Revised: 05/21/2008] [Accepted: 06/12/2008] [Indexed: 12/19/2022]
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Fan RH, Does MD. Compartmental relaxation and diffusion tensor imaging measurements in vivo in lambda-carrageenan-induced edema in rat skeletal muscle. NMR IN BIOMEDICINE 2008; 21:566-73. [PMID: 18041804 PMCID: PMC2694448 DOI: 10.1002/nbm.1226] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Integrated diffusion tensor T(2) measurements were made on normal and edematous rat muscle, and the data were fitted with one- and two-compartment models, respectively. Edematous muscle exhibited a short-lived component (T(2) = 28 +/- 6 ms), with diffusion characteristics similar to that of normal muscle, and a long-lived component (T(2) = 96 +/- 27 ms), with greater mean apparent diffusion coefficient (ADC) and lower fractional anisotropy (FA). With this two-component description of diffusion and relaxation, values of ADC and FA estimated with a conventional pulsed-gradient spin-echo sequence will depend on the echo time, relative fraction of short-lived and long-lived water signals, and the intrinsic ADC and FA values within the tissue. On the basis of the relative differences in water diffusion properties between long-lived and short-lived water signals, as well as the similarities between the short-lived component and normal tissue, it is postulated that these two signal components largely reflect intracellular and extracellular water.
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Affiliation(s)
- Reuben H. Fan
- Department of Biomedical Engineering, Vanderbilt University School of Engineering
- Vanderbilt University Institute of Imaging Science, Vanderbilt University
| | - Mark D. Does
- Department of Biomedical Engineering, Vanderbilt University School of Engineering
- Department of Radiology and Radiological Sciences, Vanderbilt University School of Medicine
- Vanderbilt University Institute of Imaging Science, Vanderbilt University
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Damon BM, Wadington MC, Lansdown DA, Hornberger JL. Spatial heterogeneity in the muscle functional MRI signal intensity time course: effect of exercise intensity. Magn Reson Imaging 2008; 26:1114-21. [PMID: 18508220 DOI: 10.1016/j.mri.2008.01.023] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2007] [Revised: 11/19/2007] [Accepted: 01/06/2008] [Indexed: 11/25/2022]
Abstract
It has previously been observed that during isometric dorsiflexion exercise, the time course of T2-weighted signal intensity (SI) changes is spatially heterogeneous. The purpose of this study was to test the hypothesis that this spatial heterogeneity would increase at higher contraction intensities. Eight subjects performed 90-s isometric dorsiflexion contractions at 30% and 60% of maximum voluntary contraction (MVC) while T2-weighted (repetition time/echo time=4000/35 ms) images were acquired. SI was measured before, during and after the contractions in regions of interest (ROIs) in the extensor digitorum longus (EDL) muscle and the deep and superficial compartments of the tibialis anterior (D-TA and S-TA, respectively). For all ROIs at 30% MVC, SI changes were similar. The maximum postcontraction SI was greater than the SI during exercise. At 60% MVC, SI changes during contraction were greater in the S-TA than in the D-TA and EDL. For the EDL and D-TA, the maximum postcontraction SI was greater than those during exercise. For the S-TA, the maximum postcontraction change was greater than the changes at t=8, 20 and 56 s but not the end-exercise value. We conclude that spatial heterogeneity increases during more intense dorsiflexion contractions, possibly reflecting regional differences in perfusion or neural activation of the muscle.
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Affiliation(s)
- Bruce M Damon
- Institute of Imaging Science, Vanderbilt University, Nashville, TN 37232, USA.
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Damon BM, Wadington MC, Hornberger JL, Lansdown DA. Absolute and relative contributions of BOLD effects to the muscle functional MRI signal intensity time course: effect of exercise intensity. Magn Reson Med 2007; 58:335-45. [PMID: 17654591 PMCID: PMC4440487 DOI: 10.1002/mrm.21319] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The time course of exercise-induced T(2)-weighted signal intensity (SI) changes contains an initial rise, early dip, and secondary rise. The purposes of this study were to test the hypothesis that the secondary rise occurs earlier during more intense contractions, and to determine the contribution of BOLD contrast to the SI changes. Eight subjects performed 90-s isometric dorsiflexion contractions at 30% and 60% of maximum voluntary contraction (MVC) while T(2)-weighted (TR/TE = 4000 ms/35 ms) images were acquired and total hemoglobin ([THb]) and oxy-Hb saturation (%HbO(2)) were measured. At 30% MVC, [THb] remained constant and %HbO(2) decreased from 66.3% (standard error [SEM] = 2.6%) to 32.4% (SEM = 6.4%). At t = 88 s, SI increased by approximately 8% and was greater than at t = 8 and 56 s. At 60% MVC, [THb] remained constant and %HbO(2) decreased from 70.2% (SEM = 2.3%) to 40.4% (SEM = 5.4%). SI increased by approximately 17% and at t = 56 and 88 s was greater than at t = 8 and 20 s. The absolute contribution of calculated BOLD effects was -1% at 30% and 60% MVC. The relative contribution was greater at 30% than at 60% MVC (up to -26% and -10%, respectively). We conclude that the secondary rise occurs earlier at 60% MVC and that the relative contribution of BOLD effects is greater during less intense contractions.
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Affiliation(s)
- Bruce M Damon
- Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee 37232, USA.
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45
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Damon BM, Hornberger JL, Wadington MC, Lansdown DA, Kent-Braun JA. Dual gradient-echo MRI of post-contraction changes in skeletal muscle blood volume and oxygenation. Magn Reson Med 2007; 57:670-9. [PMID: 17390346 PMCID: PMC4437703 DOI: 10.1002/mrm.21191] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Analysis of post-contraction MRI signal intensity (SI) transients may allow noninvasive studies of microvascular reactivity and blood oxygenation recovery. The purpose of this study was to determine the physiological basis for post-contraction changes in short-echo (6 ms) and long-echo (46 ms) gradient-echo (GRE) MRI signals (S(6) and S(46), respectively). Six healthy subjects were studied with the use of dual GRE MRI and near-infrared spectroscopy (NIRS). S(6), S(46), total hemoglobin concentration ([THb]), and oxyhemoglobin saturation (%HbO(2)) were measured before, during, and after 2 and 8 s dorsiflexion maximal voluntary contractions, and 5 min of proximal arterial occlusion. The changes in S(6) and [THb] after the 2-s contractions were similar to those following 8-s contractions, but changes in %HbO(2) and S(46) were greater following 8-s contractions than after the 2-s contractions. [THb] and S(6) did not change during and following 5 min of arterial occlusion, but %HbO(2) and S(46) were both significantly depressed at similar occlusion durations. Also, distance measures indicated similarity between S(6) and [THb] and between S(46) and %HbO(2). We conclude that following brief human skeletal muscle contractions, changes in S(6) primarily reflect changes in blood volume and changes in S(46) primarily reflect changes in blood oxygenation.
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Affiliation(s)
- Bruce M Damon
- Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee, USA.
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Raja MK, Raymer GH, Moran GR, Marsh G, Thompson RT. Changes in tissue water content measured with multiple-frequency bioimpedance and metabolism measured with 31P-MRS during progressive forearm exercise. J Appl Physiol (1985) 2006; 101:1070-5. [PMID: 16794019 DOI: 10.1152/japplphysiol.01322.2005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Multiple-frequency bioimpedance analysis (MFBIA) has been used to determine the cellular water composition in the human body. It is noninvasive and has demonstrated good correlations with other invasive measures of tissue water. However, the ability of this method to study transient changes in tissue water in specific muscle groups has not been explored. In this study, MFBIA was used to assess changes in forearm intracellular water (ICW), extracellular water (ECW), and total water (TW) in seven healthy volunteers during and after a progressive wrist flexion exercise protocol. In an identical trial, (31)P magnetic resonance spectroscopy ((31)P-MRS) was used to assess changes in intracellular pH and phosphocreatine (PCr). At the completion of exercise, forearm ICW increased 12.6% (SD 0.07, P = 0.003), TW increased 10.1% (SD 0.06, P = 0.005), and no significant changes were recorded for ECW. A significant correlation was found between the changes in intracellular pH and changes in ICW during exercise (r = -0.84, P = 0.018). With the use of regression analysis, average changes in P(i), PCr, and pH were found to predict changes in ICW (R(2) = 0.98, P = 0.005). In conclusion, MFBIA was sensitive enough to measure transient changes in the exercising forearm muscle. The changes seen were consistent with the hypothesis that intracellular acidification and PCr hydrolysis are important mediators of cellular osmolality and therefore may be responsible for the increased volume of water in the intracellular space that is often recorded after short-term high-intensity exercise.
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Affiliation(s)
- Mohan K Raja
- Department of Radiology, St. Joseph's Health Center, University of Western Ontario, 268 Grosvenor St., London, Ontario, Canada, N6A 4V2
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Kinugasa R, Kawakami Y, Fukunaga T. Quantitative assessment of skeletal muscle activation using muscle functional MRI. Magn Reson Imaging 2006; 24:639-44. [PMID: 16735187 DOI: 10.1016/j.mri.2006.01.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2005] [Accepted: 01/05/2006] [Indexed: 10/24/2022]
Abstract
The purpose of the present study is to determine whether muscle functional MRI (mfMRI) can be used to obtain three-dimensional (3-D) images useful for evaluating muscle activity, and if so, to measure the distribution of muscle activity within a medial gastrocnemius (MG) muscle. Seven men performed 5 sets of 10 repetitions of a calf-raise exercise with additional 15% of body-weight load. Magnetic resonance images were obtained before and immediately after the exercise. To threshold images, only those pixels showing transverse relaxation time (T2) greater than the mean+1 S.D. of the entire regions of interest (ROIs) in the preexercise image and T2 lower than the mean+1 S.D. of the entire ROIs in the postexercise image were identified. The survived pixels showing T2 are defined as active muscle. Those thresholded images were 3-D reconstructed, and this was used to determine area of active muscle along transverse, longitudinal and vertical axes. At the exercise level used in the present study, the percentage volume of activated muscle in the MG was 62.8+/-4.5%. There was a significant correlation between percentage volume of activated muscle and integrated electromyography (r=.78, P<.05). Percentage areas of activated muscle were significantly larger in the medial than in the lateral region, in the anterior than in the posterior region and in the distal than in the proximal region (P<.05). These results suggest that mfMRI can be used to evaluate the muscle activity and to determine intramuscular variations of activity within skeletal muscle.
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Affiliation(s)
- Ryuta Kinugasa
- Research Center of Sports Sciences, Musashino University, 1-1-20 Shinmachi, Nishitokyo, Tokyo 202-8585, Japan.
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Forbes JG, Morris HD, Wang K. Multimodal imaging of the sonic organ of Porichthys notatus, the singing midshipman fish. Magn Reson Imaging 2006; 24:321-31. [PMID: 16563962 DOI: 10.1016/j.mri.2005.10.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2005] [Accepted: 10/20/2005] [Indexed: 10/25/2022]
Abstract
The sonic midshipman fish, Porichthys notatus, is a bottom-dwelling species whose swim bladder has evolved into a highly specialized, sound-producing organ. The males of this species exist in two distinct morphs with different physical characteristics and sexual strategies. The Type I males have a much larger sound organ and are capable of generating a loud approximately 100 Hz tone continuously for over an hour to attract females. This sound is produced by sonic muscle and represents one of the most superfast and super-enduring striated muscles found in nature. Each fiber contains a hollow, tubular contractile apparatus composed of radially arranged myofibrils with extremely broad Z-bands that are supported by a desmin-rich cytoskeleton. We have used micro computed tomography (CT) imaging and magnetic resonance (MR) imaging to visualize the location of the sonic organ in an intact male fish. We have also obtained high-resolution MR images of the excised swim bladders from both male types. The images of the Type I sonic organ are strikingly detailed and high-contrast, revealing both the internal organization of the bladder and the crisscrossing muscle fibers and their mode of attachment to the underlying bladder. The high-contrast variation in these images is due to different T(2) values for fiber bundles and the spaces between the bundles. Direct MR imaging of intact Type I sonic organ in Type I midshipman fish is a powerful approach to understanding the contraction of this superfast muscle and the oscillation of its bladder to produce mating calls, and how placement of the sonic organ in the body of the fish sheds light on its prodigious ability to produce and transmit its loud mating call.
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Affiliation(s)
- Jeffrey G Forbes
- Muscle Proteomics and Nanotechnology Section, Laboratory of Muscle Biology, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892-8024, USA
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Raymer GH, Allman BL, Rice CL, Marsh GD, Thompson RT. Characteristics of a MR-compatible ankle exercise ergometer for a 3.0 T head-only MR scanner. Med Eng Phys 2005; 28:489-94. [PMID: 16162418 DOI: 10.1016/j.medengphy.2005.07.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2004] [Revised: 07/19/2005] [Accepted: 07/26/2005] [Indexed: 11/26/2022]
Abstract
An exercise ergometer, for isometric or dynamic contraction of both dorsiflexion and/or plantarflexion exercise, was designed and constructed for a 3.0 T head-only MR scanner. The principal features of this MR-compatible ergometer include electronic devices for quantification of force (during isometric exercise) and angular displacement (during dynamic exercise), without any significant losses to external motions or frictions. The ergometer was also made to be adjustable for subject leg length and was designed for suspension within the bore of the magnet to eliminate transmission of force and vibration to the MR scanner. A description of the design and construction, as well as the important technical features, is presented herein.
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Affiliation(s)
- Graydon H Raymer
- Department of Medical Biophysics, The University of Western Ontario, London, Ont., Canada N6A 5C1.
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Bertram HC, Stagsted J, Young JF, Andersen HJ. Elucidation of membrane destabilization in post-mortem muscles using an extracellular paramagnetic agent (Gd-DTPA): an NMR study. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2004; 52:6320-6325. [PMID: 15453707 DOI: 10.1021/jf049452b] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The effect of Gd-DTPA on the development in NMR relaxation of skeletal rabbit muscles post-mortem was investigated by dynamic low-field (0.47 T) relaxation measurements from 4 min post-mortem and until 23 h post-mortem. Twelve rabbits were included in the study, and half of the animals were administered 0.2 mmol of Gd-DTPA iv 15 min before sacrifice, while the other half was administered an isotonic salt solution. A significant effect of Gd-DTPA treatment corresponding to a 25% reduction in the T(1) relaxation time was observed. T(2) relaxation was decomposed into two components reflecting intra- and extracellular components (T(2)()alpha and T(2)()beta, respectively), and Gd-DTPA treatment was found to affect both components. However, around 150 min post-mortem a dramatic increase in the difference between control and Gd-DTPA-treated rabbits was observed in the relaxation time of the intracellular water population (T(2)()alpha). Electrical stimulation of the muscles resulted in a significantly earlier onset of the increased effect of Gd-DTPA on the T(2)()alpha population. The increased effect of Gd-DTPA treatment on the T(2)()alpha component is believed to reflect leakage of water from the muscle cells due to membrane destabilization, known to be promoted by electrical stimulation. Accordingly, the present study demonstrates how Gd-DTPA can be used for probing membrane integrity in post-mortem muscles known to be of importance for subsequent water distribution and final water-holding capacity.
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Affiliation(s)
- Hanne Christine Bertram
- Department of Food Science, Danish Institute of Agricultural Sciences, Research Centre Foulum, P.O. Box 50, DK-8830 Tjele, Denmark.
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