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Gao F, Li JJ, Liu JY, Li YJ, Cong XY, Talifu Z, Zhang X. Association between brain N-acetylaspartate levels and sensory and motor dysfunction in patients who have spinal cord injury with spasticity: an observational case-control study. Neural Regen Res 2023; 18:582-586. [DOI: 10.4103/1673-5374.350216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Ferris JK, Neva JL, Vavasour IM, Attard KJ, Greeley B, Hayward KS, Wadden KP, MacKay AL, Boyd LA. Cortical N-acetylaspartate concentrations are impacted in chronic stroke but do not relate to motor impairment: A magnetic resonance spectroscopy study. Hum Brain Mapp 2021; 42:3119-3130. [PMID: 33939206 PMCID: PMC8193507 DOI: 10.1002/hbm.25421] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 02/24/2021] [Accepted: 03/08/2021] [Indexed: 12/11/2022] Open
Abstract
Magnetic resonance spectroscopy (MRS) measures cerebral metabolite concentrations, which can inform our understanding of the neurobiological processes associated with stroke recovery. Here, we investigated whether metabolite concentrations in primary motor and somatosensory cortices (sensorimotor cortex) are impacted by stroke and relate to upper‐extremity motor impairment in 45 individuals with chronic stroke. Cerebral metabolite estimates were adjusted for cerebrospinal fluid and brain tissue composition in the MRS voxel. Upper‐extremity motor impairment was indexed with the Fugl‐Meyer (FM) scale. N‐acetylaspartate (NAA) concentration was reduced bilaterally in stroke participants with right hemisphere lesions (n = 23), relative to right‐handed healthy older adults (n = 15; p = .006). Within the entire stroke sample (n = 45) NAA and glutamate/glutamine (GLX) were lower in the ipsilesional sensorimotor cortex, relative to the contralesional cortex (NAA: p < .001; GLX: p = .003). Lower ipsilesional NAA was related to greater extent of corticospinal tract (CST) injury, quantified by a weighted CST lesion load (p = .006). Cortical NAA and GLX concentrations did not relate to the severity of chronic upper‐extremity impairment (p > .05), including after a sensitivity analysis imputing missing metabolite data for individuals with large cortical lesions (n = 5). Our results suggest that NAA, a marker of neuronal integrity, is sensitive to stroke‐related cortical damage and may provide mechanistic insights into cellular processes of cortical adaptation to stroke. However, cortical MRS metabolites may have limited clinical utility as prospective biomarkers of upper‐extremity outcomes in chronic stroke.
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Affiliation(s)
- Jennifer K Ferris
- Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jason L Neva
- École de Kinésiologie et des Sciences de l'activité Physique, Université of Montréal, Montreal, Quebec, Canada.,Centre de Recherche de l'Institut Universitaire de Gériatrie de Montréal, CIUSSS Centre-sud-de-I'île de Montréal, Montreal, Quebec, Canada
| | - Irene M Vavasour
- Faculty of Medicine, UBC MRI Research Center, University of British Columbia, Vancouver, BC, Canada
| | - Kaitlin J Attard
- Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Brian Greeley
- Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kathryn S Hayward
- School of Health Sciences, Florey Institute of Neuroscience and Mental Health, NHMRC CRE in Stroke Rehabilitation and Brain Recovery, The University of Melbourne, Parkville, Victoria, Australia
| | - Katie P Wadden
- Faculty of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| | - Alex L MacKay
- Faculty of Medicine, UBC MRI Research Center, University of British Columbia, Vancouver, BC, Canada
| | - Lara A Boyd
- Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada
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Austin T, Bani-Ahmed A, Cirstea MC. N-Acetylaspartate Biomarker of Stroke Recovery: A Case Series Study. FRONTIERS IN NEUROLOGY AND NEUROSCIENCE RESEARCH 2021; 2:100007. [PMID: 34296219 PMCID: PMC8294783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
BACKGROUND AND PURPOSE Strong experimental neurobehavioral evidence suggests that intensive training improves arm motor disability after stroke. Yet, we still have only limited understanding why some patients recover more completely and others do not. This is in part due to our limited knowledge of the neurobiological principles of recovery from stroke. Mounting evidence suggests that functional and structural remapping of the primary motor cortex (M1) plays a major role in arm recovery after stroke. We used MR Spectroscopy to test the hypothesis that therapy-related arm improvement is associated with changes in levels of a putative marker of neuronal integrity (N-acetylaspartate, NAA) in M1 controlling the paretic arm (ipsilesional M1) in chronic stroke patients (n=5). METHODS Patients (1 female, age, mean ± SD, 58.4 ± 5.8 years) underwent 4-week arm-focused motor training (1080 repetitions of a reach-to-grasp task) at 13.6 ± 5.3 months after stroke onset. NAA levels in the ipsilesional M1 and arm impairment (Fugl-Meyer, FM, 66=normal; proximal FM, FMp, 30=normal) were assessed prior to and immediately after training. RESULTS At baseline, patients exhibited moderate-to-mild arm impairment (FM, 47.2 ± 18.8, FMp, 22.2 ± 8.6) and showed lower levels of NAA compared with age/sex-matched healthy controls (10.2 ± 0.9 mM in patients vs. 11.6 ± 1.6 mM in controls, p=0.03). After training, arm impairment improved (FM by 7%, 50.6 ± 17.5, p=0.01; FMp, by 5%, 23.4 ± 8.2, p=0.2) and NAA levels increased by 10.5% (11.2 ± 1.2 mM, p=0.1). Changes in NAA positively correlated with changes in FM (r=0.63, p=0.2) and FMp (r=0.93, p=0.03), suggesting that patients who show greater neuronal changes have a better chance of recovery. CONCLUSIONS Our data suggest the potential use of M1 NAA as a biomarker of motor recovery after stroke. However, because of our small sample, these preliminary results should be interpreted cautiously. Further work with larger sample sizes is warranted.
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Affiliation(s)
- Tyler Austin
- University of Missouri School of Medicine, Columbia, Missouri, USA
| | - Ali Bani-Ahmed
- Hoglund Brain Imaging Center, University of Kansas Medical Center, Kansas City, Kansas, USA
- Department of Physical Therapy & Rehabilitation Science, University of Kansas Medical Center, Kansas City, Kansas, USA
- Department of Rehabilitation Sciences, Jordan University of Science and Technology, Ar-Ramtha, Jordan
| | - Mihaela Carmen Cirstea
- Hoglund Brain Imaging Center, University of Kansas Medical Center, Kansas City, Kansas, USA
- Department of Physical Therapy & Rehabilitation Science, University of Kansas Medical Center, Kansas City, Kansas, USA
- Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas, USA
- Department of Physical Medicine & Rehabilitation, University of Missouri, Columbia, Missouri, USA
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Mostafa MM, Awad EM, Hazzou AM, Elewa MKA, Aziz TTA, Samy DM. Biochemical and structural magnetic resonance imaging in chronic stroke and the relationship with upper extremity motor function. THE EGYPTIAN JOURNAL OF NEUROLOGY, PSYCHIATRY AND NEUROSURGERY 2020. [DOI: 10.1186/s41983-020-00183-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Recovery of upper extremity (UE) motor function after stroke is variable from one to another due to heterogeneity of stroke pathology. Structural and biochemical magnetic resonance imaging of the primary motor cortex (M1) have been used to document reorganization of neural activity after stroke.
Objective
To assess cortical biochemical and structural causes of delayed recovery of UE motor function impairment in chronic subcortical ischemic stroke patients.
Methodology
A cross-sectional study with fifty patients were enrolled: thirty patients with chronic (> 6 months) subcortical ischemic stroke suffering from persistent UE motor function impairment (not improved group) and twenty patients with chronic subcortical ischemic stroke and improved UE motor function (improved group). We recruited a group of (16) age-matched healthy subjects. Single voxel proton magnetic resonance spectroscopy (1H-MRS) was performed to measure n-acetylaspartate (NAA) and glutamate+glutamine (Glx) ratios relative to creatine (Cr) in the precentral gyrus which represent M1of hand area in both ipsilesional and contralesional hemispheres. Brain magnetic resonance imaging (MRI) to measure precentral gyral thickness is representing the M1of hand area. UE motor function assessment is using the Fugl Meyer Assessment (FMA-UE) Scale.
Results
The current study found that ipslesional cortical thickness was significantly lower than contralesional cortical thickness among all stroke patients. Our study found that ipsilesional NAA/Cr ratio was lower than contralesional NAA/Cr among stroke patients. UE and hand motor function by FMA-UE showed highly statistically significant correlation with ipsilesional cortical thickness and ipsilesional NAA/Cr ratio, more powerful with NAA/Cr ratio.
Conclusion
We concluded that persistent motor impairment in individuals with chronic subcortical stroke may be at least in part related to ipsilesional structural and biochemical changes in motor areas remote from infarction in form of decreased cortical thickness and NAA/Cr ratio which had the strongest relationship with that impairment.
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Sun C, Liu X, Bao C, Wei F, Gong Y, Li Y, Liu J. Advanced non-invasive MRI of neuroplasticity in ischemic stroke: Techniques and applications. Life Sci 2020; 261:118365. [PMID: 32871181 DOI: 10.1016/j.lfs.2020.118365] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 08/26/2020] [Accepted: 08/27/2020] [Indexed: 12/27/2022]
Abstract
Ischemic stroke represents a serious medical condition which could cause survivors suffer from long-term and even lifetime disabilities. After a stroke attack, the brain would undergo varying degrees of recovery, in which the central nervous system could be reorganized spontaneously or with the help of appropriate rehabilitation. Magnetic resonance imaging (MRI) is a non-invasive technique which can provide comprehensive information on structural, functional and metabolic features of brain tissue. In the last decade, there has been an increased technical advancement in MR techniques such as voxel-based morphological analysis (VBM), diffusion magnetic resonance imaging (dMRI), functional magnetic resonance imaging (fMRI), arterial spin-labeled perfusion imaging (ASL), magnetic sensitivity weighted imaging (SWI), quantitative sensitivity magnetization (QSM) and magnetic resonance spectroscopy (MRS) which have been proven to be a valuable tool to study the brain tissue reorganization. Due to MRI indices of neuroplasticity related to neurological outcome could be translated to the clinic. The ultimate goal of this review is to equip readers with a fundamental understanding of advanced MR techniques and their corresponding clinical application for improving the ability to predict neuroplasticity that are most suitable for stroke management.
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Affiliation(s)
- Chao Sun
- Graduate School, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, PR China
| | - Xuehuan Liu
- Department of Radiology, Tianjin Union Medical Center, Tianjin 300121, PR China
| | - Cuiping Bao
- Department of Radiology, Tianjin Union Medical Center, Tianjin 300121, PR China
| | - Feng Wei
- Department of Radiology, Tianjin Union Medical Center, Tianjin 300121, PR China
| | - Yi Gong
- Department of Radiology, Tianjin Union Medical Center, Tianjin 300121, PR China
| | - Yiming Li
- Department of Radiology, Tianjin Union Medical Center, Tianjin 300121, PR China
| | - Jun Liu
- Department of Radiology, Tianjin Union Medical Center, Tianjin 300121, PR China.
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Mazibuko N, Tuura RO, Sztriha L, O’Daly O, Barker GJ, Williams SCR, O’Sullivan M, Kalra L. Subacute Changes in N-Acetylaspartate (NAA) Following Ischemic Stroke: A Serial MR Spectroscopy Pilot Study. Diagnostics (Basel) 2020; 10:diagnostics10070482. [PMID: 32708540 PMCID: PMC7399797 DOI: 10.3390/diagnostics10070482] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 07/01/2020] [Accepted: 07/13/2020] [Indexed: 01/10/2023] Open
Abstract
Preservation of neuronal tissue is crucial for recovery after stroke, but studies suggest that prolonged neuronal loss occurs following acute ischaemia. This study assessed the temporal pattern of neuronal loss in subacute ischemic stroke patients using 1H magnetic resonance spectroscopy, in parallel with functional recovery at 2, 6 and 12 weeks after stroke. Specifically, we measured N-acetylaspartate (NAA), choline, myoinositol, creatine and lactate concentrations in the ipsilesional and contralesional thalamus of 15 first-ever acute ischaemic stroke patients and 15 control participants and correlated MRS concentrations with motor recovery, measured at 12 weeks using the Fugl-Meyer scale. NAA in the ipsilesional thalamus fell significantly between 2 and 12 weeks (10.0 to 7.97 mmol/L, p = 0.003), while choline, myoinositol and lactate concentrations increased (p = 0.025, p = 0.031, p = 0.001, respectively). Higher NAA concentrations in the ipsilesional thalamus at 2 and 12 weeks correlated with higher Fugl Meyer scores at 12 weeks (p = 0.004 and p = 0.006, respectively). While these results should be considered preliminary given the modest sample size, the progressive fall in NAA and late increases in choline, myoinositol and lactate may indicate progressive non-ischaemic neuronal loss, metabolically depressed neurons and/or diaschisis effects, which have a detrimental effect on motor recovery. Interventions that can potentially limit this ongoing subacute tissue damage may improve stroke recovery.
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Affiliation(s)
- Ndaba Mazibuko
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King’s College London, London SE5 8AF, UK; (N.M.); (L.S.); (L.K.)
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London SE5 8AF, UK (G.J.B.); (S.C.R.W.); (M.O.)
| | - Ruth O’Gorman Tuura
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London SE5 8AF, UK (G.J.B.); (S.C.R.W.); (M.O.)
- Center for MR Research, Children’s Hospital, Zürich, Steinwiesenstrasse 75, CH-8032 Zurich, Switzerland
- Correspondence:
| | - Laszlo Sztriha
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King’s College London, London SE5 8AF, UK; (N.M.); (L.S.); (L.K.)
- Department of Neurology, King’s College Hospital NHS Foundation Trust, London SE5 9RS, UK
| | - Owen O’Daly
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London SE5 8AF, UK (G.J.B.); (S.C.R.W.); (M.O.)
| | - Gareth J. Barker
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London SE5 8AF, UK (G.J.B.); (S.C.R.W.); (M.O.)
| | - Steven C. R. Williams
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London SE5 8AF, UK (G.J.B.); (S.C.R.W.); (M.O.)
| | - Michael O’Sullivan
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London SE5 8AF, UK (G.J.B.); (S.C.R.W.); (M.O.)
- UQ Centre for Clinical Research, University of Queensland, Herston, QLD 4029, Australia
| | - Lalit Kalra
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King’s College London, London SE5 8AF, UK; (N.M.); (L.S.); (L.K.)
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Ferris JK, Peters S, Brown KE, Tourigny K, Boyd LA. Type-2 diabetes mellitus reduces cortical thickness and decreases oxidative metabolism in sensorimotor regions after stroke. J Cereb Blood Flow Metab 2018; 38:823-834. [PMID: 28401788 PMCID: PMC5987933 DOI: 10.1177/0271678x17703887] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Individuals with type-2 diabetes mellitus experience poor motor outcomes after ischemic stroke. Recent research suggests that type-2 diabetes adversely impacts neuronal integrity and function, yet little work has considered how these neuronal changes affect sensorimotor outcomes after stroke. Here, we considered how type-2 diabetes impacted the structural and metabolic function of the sensorimotor cortex after stroke using volumetric magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS). We hypothesized that the combination of chronic stroke and type-2 diabetes would negatively impact the integrity of sensorimotor cortex as compared to individuals with chronic stroke alone. Compared to stroke alone, individuals with stroke and diabetes had lower cortical thickness bilaterally in the primary somatosensory cortex, and primary and secondary motor cortices. Individuals with stroke and diabetes also showed reduced creatine levels bilaterally in the sensorimotor cortex. Contralesional primary and secondary motor cortex thicknesses were negatively related to sensorimotor outcomes in the paretic upper-limb in the stroke and diabetes group such that those with thinner primary and secondary motor cortices had better motor function. These data suggest that type-2 diabetes alters cerebral energy metabolism, and is associated with thinning of sensorimotor cortex after stroke. These factors may influence motor outcomes after stroke.
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Affiliation(s)
- Jennifer K Ferris
- 1 Faculty of Medicine, Graduate program of Rehabilitation Sciences, University of British Columbia, Vancouver, Canada
| | - Sue Peters
- 1 Faculty of Medicine, Graduate program of Rehabilitation Sciences, University of British Columbia, Vancouver, Canada
| | - Katlyn E Brown
- 1 Faculty of Medicine, Graduate program of Rehabilitation Sciences, University of British Columbia, Vancouver, Canada
| | - Katherine Tourigny
- 2 Department of Psychology, University of British Columbia, Vancouver, Canada
| | - Lara A Boyd
- 1 Faculty of Medicine, Graduate program of Rehabilitation Sciences, University of British Columbia, Vancouver, Canada.,3 Department of Physical Therapy, University of British Columbia, Vancouver, Canada.,4 Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada
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8
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Jones PW, Borich MR, Vavsour I, Mackay A, Boyd LA. Cortical thickness and metabolite concentration in chronic stroke and the relationship with motor function. Restor Neurol Neurosci 2018; 34:733-46. [PMID: 27258945 DOI: 10.3233/rnn-150623] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Hemiparesis is one of the most prevalent chronic disabilities after stroke. Biochemical and structural magnetic resonance imaging approaches may be employed to study the neural substrates underpinning upper-extremity (UE) recovery after chronic stroke. OBJECTIVE The purposes of this study were to 1) quantify anatomical and metabolic differences in the precentral gyrus, and 2) test the relationships between anatomical and metabolic differences, and hemiparetic arm function in individuals in the chronic stage of stroke recovery. Our hypotheses were: 1) the Stroke group would exhibit reduced precentral gyrus cortical thickness and lower concentrations of total N-acetylaspartate (tNAA) and glutamate+glutamine (Glx) in the ipsilesional motor cortex; and 2) that each of these measures would be associated with UE motor function after stroke. METHODS Seventeen individuals with chronic (>6 months) subcortical ischemic stroke and eleven neurologically healthy controls were recruited. Single voxel proton magnetic resonance spectroscopy (H1MRS) was performed to measure metabolite concentrations of tNAA and Glx in the precentral gyrus in both ipsilesional and contralesional hemispheres. Surface-based cortical morphometry was used to quantify precentral gyral thickness. Upper-extremity motor function was assessed using the Wolf Motor Function Test (WMFT). RESULTS Results demonstrated significantly lower ipsilesional tNAA and Glx concentrations and precentral gyrus thickness in the Stroke group. Ipsilesional tNAA and Glx concentration and precentral gyrus thickness was significantly lower in the ipsilesional hemisphere in the Stroke group. Parametric correlation analyses revealed a significant positive relationship between precentral gyrus thickness and tNAA concentration bilaterally. Multivariate regression analyses revealed that ipsilesional concentrations of tNAA and Glx predicted the largest amount of variance in WMFT scores. Cortical thickness measures alone did not predict a significant amount of variance in WMFT scores. CONCLUSION While stroke impairs both structure and biochemistry in the ipsilesional hemisphere our data suggest that tNAA has the strongest relationship with motor function.
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Affiliation(s)
- Paul W Jones
- Graduate Program in Neuroscience, University of British Columbia, Wesbrook Mall, Vancouver, Canada
| | - Michael R Borich
- Division of Physical Therapy, Department of Rehabilitation Medicine, Emory University School of Medicine, Clifton Road NE, Atlanta, Georgia, USA
| | - Irene Vavsour
- Department of Radiology, University of British Columbia, Vancouver, Canada
| | - Alex Mackay
- Department of Physics, University of British Columbia, Agricultural Road, Vancouver, Canada
| | - Lara A Boyd
- Department of Physical Therapy, University of British Columbia, Wesbrook Mall, Vancouver, Canada.,Centre for Brain Health, University of British Columbia, Wesbrook Mall, Vancouver, Canada
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9
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Cirstea CM, Lee P, Craciunas SC, Choi IY, Burris JE, Nudo RJ. Pre-therapy Neural State of Bilateral Motor and Premotor Cortices Predicts Therapy Gain After Subcortical Stroke: A Pilot Study. Am J Phys Med Rehabil 2017; 97:23-33. [PMID: 28737516 DOI: 10.1097/phm.0000000000000791] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
OBJECTIVE The aim of the study was to examine whether neural state of spared motor and premotor cortices captured before a therapy predicts therapy-related motor gains in chronic subcortical stroke. DESIGN Ten survivors, presenting chronic moderate upper limb impairment, underwent proton magnetic resonance spectroscopy, magnetic resonance imaging, clinical, and kinematics assessments before a 4-wk impairment-oriented training. Clinical/kinematics assessments were repeated after therapy, and motor gain was defined as positive values of clinical upper limb/elbow motion changes and negative values of trunk motion changes. Candidate predictors were N-acetylaspartate-neuronal marker, glutamate-glutamine-indicator of glutamatergic neurotransmission, and myo-inositol-glial marker, measured bilaterally within the upper limb territory in motor and premotor (premotor cortex, supplementary motor area) cortices. Traditional predictors (age, stroke length, pre-therapy upper limb clinical impairment, infarct volume) were also investigated. RESULTS Poor motor gain was associated with lower glutamate-glutamine levels in ipsilesional primary motor cortex and premotor cortex (r = 0.77, P = 0.01 and r = 0.78, P = 0.008, respectively), lower N-acetylaspartate in ipsilesional premotor cortex (r = 0.69, P = 0.02), higher glutamate-glutamine in contralesional primary motor cortex (r = -0.68, P = 0.03), and lower glutamate-glutamine in contralesional supplementary motor area (r = 0.64, P = 0.04). These predictors outperformed myo-inositol metrics and traditional predictors (P ≈ 0.05-1.0). CONCLUSIONS Glutamatergic state of bilateral motor and premotor cortices and neuronal state of ipsilesional premotor cortex may be important for predicting motor outcome in the context of a restorative therapy.
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Affiliation(s)
- Carmen M Cirstea
- From the Departments of Neurology (CMC, I-YC), Molecular & Integrative Physiology (PL), Physical Medicine & Rehabilitation (RJN); Hoglund Brain Imaging Center (CMC, PL, SCC, I-YC), Landon Center on Aging (RJN), University of Kansas Medical Center, Kansas City, Kansas; and Department of Physical Medicine and Rehabilitation, University of Missouri, Columbia, Missouri (CMC, JEB)
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10
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Cirstea CM, Choi IY, Lee P, Peng H, Kaufman CL, Frey SH. Magnetic resonance spectroscopy of current hand amputees reveals evidence for neuronal-level changes in former sensorimotor cortex. J Neurophysiol 2017; 117:1821-1830. [PMID: 28179478 DOI: 10.1152/jn.00329.2016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 01/23/2017] [Accepted: 01/23/2017] [Indexed: 11/22/2022] Open
Abstract
Deafferentation is accompanied by large-scale functional reorganization of maps in the primary sensory and motor areas of the hemisphere contralateral to injury. Animal models of deafferentation suggest a variety of cellular-level changes including depression of neuronal metabolism and even neuronal death. Whether similar neuronal changes contribute to patterns of reorganization within the contralateral sensorimotor cortex of chronic human amputees is uncertain. We used functional MRI-guided proton magnetic resonance spectroscopy to test the hypothesis that unilateral deafferentation is associated with lower levels of N-acetylaspartate (NAA, a putative marker of neuronal integrity) in the sensorimotor hand territory located contralateral to the missing hand in chronic amputees (n = 19) compared with the analogous hand territory of age- and sex-matched healthy controls (n = 28). We also tested whether former amputees [i.e., recipients of replanted (n = 3) or transplanted (n = 2) hands] exhibit NAA levels that are indistinguishable from controls, possible evidence for reversal of the effects of deafferentation. As predicted, relative to controls, current amputees exhibited lower levels of NAA that were negatively and significantly correlated with the time after amputation. Contrary to our prediction, NAA levels in both replanted and transplanted patients fell within the range of the current amputees. We suggest that lower levels of NAA in current amputees reflects altered neuronal integrity consequent to chronic deafferentation. Thus local changes in NAA levels may provide a means of assessing neuroplastic changes in deafferented cortex. Results from former amputees suggest that these changes may not be readily reversible through reafferentation.NEW & NOTEWORTHY This study is the first to use functional magnetic resonance-guided magnetic resonance spectroscopy to examine neurochemical mechanisms underlying functional reorganization in the primary somatosensory and motor cortices consequent to upper extremity amputation and its potential reversal through hand replantation or transplantation. We provide evidence for selective alteration of cortical neuronal integrity associated with amputation-related deafferentation that may not be reversible.
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Affiliation(s)
- Carmen M Cirstea
- Department of Physical Medicine and Rehabilitation, University of Missouri, Columbia, Missouri; .,Department of Neurology, Kansas University Medical Center, Kansas City, Kansas
| | - In-Young Choi
- Department of Neurology, Kansas University Medical Center, Kansas City, Kansas
| | - Phil Lee
- Department of Molecular and Integrative Physiology, Kansas University Medical Center, Kansas City, Kansas
| | - Huiling Peng
- Department of Psychological Sciences, University of Missouri, Columbia, Missouri.,Brain Imaging Center, University of Missouri, Columbia, Missouri; and
| | | | - Scott H Frey
- Department of Psychological Sciences, University of Missouri, Columbia, Missouri
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11
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Carlson HL, MacMaster FP, Harris AD, Kirton A. Spectroscopic biomarkers of motor cortex developmental plasticity in hemiparetic children after perinatal stroke. Hum Brain Mapp 2017; 38:1574-1587. [PMID: 27859933 PMCID: PMC6866903 DOI: 10.1002/hbm.23472] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 10/20/2016] [Accepted: 11/07/2016] [Indexed: 01/26/2023] Open
Abstract
Perinatal stroke causes hemiparetic cerebral palsy and lifelong motor disability. Bilateral motor cortices are key hubs within the motor network and their neurophysiology determines clinical function. Establishing biomarkers of motor cortex function is imperative for developing and evaluating restorative interventional strategies. Proton magnetic resonance spectroscopy (MRS) quantifies metabolite concentrations indicative of underlying neuronal health and metabolism in vivo. We used functional magnetic resonance imaging (MRI)-guided MRS to investigate motor cortex metabolism in children with perinatal stroke. Children aged 6-18 years with MRI-confirmed perinatal stroke and hemiparetic cerebral palsy were recruited from a population-based cohort. Metabolite concentrations were assessed using a PRESS sequence (3T, TE = 30 ms, voxel = 4 cc). Voxel location was guided by functional MRI activations during finger tapping tasks. Spectra were analysed using LCModel. Metabolites were quantified, cerebral spinal fluid corrected and compared between groups (ANCOVA) controlling for age. Associations with clinical motor performance (Assisting Hand, Melbourne, Box-and-Blocks) were assessed. Fifty-two participants were studied (19 arterial, 14 venous, 19 control). Stroke participants demonstrated differences between lesioned and nonlesioned motor cortex N-acetyl-aspartate [NAA mean concentration = 10.8 ± 1.9 vs. 12.0 ± 1.2, P < 0.01], creatine [Cre 8.0 ± 0.9 vs. 7.4 ± 0.9, P < 0.05] and myo-Inositol [Ins 6.5 ± 0.84 vs. 5.8 ± 1.1, P < 0.01]. Lesioned motor cortex NAA and creatine were strongly correlated with motor performance in children with arterial but not venous strokes. Interrogation of motor cortex by fMRI-guided MRS is feasible in children with perinatal stroke. Metabolite differences between hemispheres, stroke types and correlations with motor performance support functional relevance. MRS may be valuable in understanding the neurophysiology of developmental neuroplasticity in cerebral palsy. Hum Brain Mapp 38:1574-1587, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Helen L. Carlson
- Calgary Pediatric Stroke ProgramAlberta Children's HospitalCalgaryABCanada
- Alberta Children's Hospital Research Institute (ACHRI)ABCanadaCalgary
- NeurosciencesAlberta Children's HospitalCalgaryABCanada
- Department of PediatricsUniversity of CalgaryCalgaryABCanada
| | - Frank P. MacMaster
- Alberta Children's Hospital Research Institute (ACHRI)ABCanadaCalgary
- Department of PediatricsUniversity of CalgaryCalgaryABCanada
- Hotchkiss Brain Institute, University of CalgaryCalgaryABCanada
- Department of PsychiatryUniversity of CalgaryABCanada
- The Mathison Centre for Mental Health Research and Education, University of CalgaryCalgaryABCanada
- Child and Adolescent Imaging Research (CAIR) Programs, Alberta Children's HospitalCalgaryABCanada
- Strategic Clinical Network for Addictions and Mental HealthAlberta Health ServicesCalgaryABCanada
| | - Ashley D. Harris
- Alberta Children's Hospital Research Institute (ACHRI)ABCanadaCalgary
- Hotchkiss Brain Institute, University of CalgaryCalgaryABCanada
- Child and Adolescent Imaging Research (CAIR) Programs, Alberta Children's HospitalCalgaryABCanada
- Department of RadiologyUniversity of CalgaryCalgaryABCanada
| | - Adam Kirton
- Calgary Pediatric Stroke ProgramAlberta Children's HospitalCalgaryABCanada
- Alberta Children's Hospital Research Institute (ACHRI)ABCanadaCalgary
- NeurosciencesAlberta Children's HospitalCalgaryABCanada
- Department of PediatricsUniversity of CalgaryCalgaryABCanada
- Hotchkiss Brain Institute, University of CalgaryCalgaryABCanada
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12
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Constraint-Induced Movement Therapy Combined with Transcranial Direct Current Stimulation over Premotor Cortex Improves Motor Function in Severe Stroke: A Pilot Randomized Controlled Trial. Rehabil Res Pract 2017; 2017:6842549. [PMID: 28250992 PMCID: PMC5303863 DOI: 10.1155/2017/6842549] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 11/24/2016] [Accepted: 12/19/2016] [Indexed: 12/16/2022] Open
Abstract
Objective. We compared the effects of transcranial direct current stimulation at different cortical sites (premotor and motor primary cortex) combined with constraint-induced movement therapy for treatment of stroke patients. Design. Sixty patients were randomly distributed into 3 groups: Group A, anodal stimulation on premotor cortex and constraint-induced movement therapy; Group B, anodal stimulation on primary motor cortex and constraint-induced movement therapy; Group C, sham stimulation and constraint-induced movement therapy. Evaluations involved analysis of functional independence, motor recovery, spasticity, gross motor function, and muscle strength. Results. A significant improvement in primary outcome (functional independence) after treatment in the premotor group followed by primary motor group and sham group was observed. The same pattern of improvement was highlighted among all secondary outcome measures regarding the superior performance of the premotor group over primary motor and sham groups. Conclusions. Premotor cortex can contribute to motor function in patients with severe functional disabilities in early stages of stroke. This study was registered in ClinicalTrials.gov database (NCT 02628561).
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13
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Jang SH, Seo JP, Lee SH, Jin SH, Yeo SS. The cortical activation pattern during bilateral arm raising movements. Neural Regen Res 2017; 12:317-320. [PMID: 28400816 PMCID: PMC5361518 DOI: 10.4103/1673-5374.200817] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Bilateral arm raising movements have been used in brain rehabilitation for a long time. However, no study has been reported on the effect of these movements on the cerebral cortex. In this study, using functional near infrared spectroscopy (fNIRS), we attempted to investigate cortical activation generated during bilateral arm raising movements. Ten normal subjects were recruited for this study. fNIRS was performed using an fNIRS system with 49 channels. Bilateral arm raising movements were performed in sitting position at the rate of 0.5 Hz. We measured values of oxyhemoglobin and total hemoglobin in five regions of interest: the primary sensorimotor cortex, premotor cortex, supplementary motor area, prefrontal cortex, and posterior parietal cortex. During performance of bilateral arm raising movements, oxyhemoglobin and total hemoglobin values in the primary sensorimotor cortex, premotor cortex, supplementary motor area, and prefrontal cortex were similar, but higher in these regions than those in the prefrontal cortex. We observed activation of the arm somatotopic areas of the primary sensorimotor cortex and premotor cortex in both hemispheres during bilateral arm raising movements. According to this result, bilateral arm raising movements appeared to induce large-scale neuronal activation and therefore arm raising movements would be good exercise for recovery of brain functions.
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Affiliation(s)
- Sung Ho Jang
- Department of Physical Medicine and Rehabilitation, College of Medicine, Yeungnam University, Daegu, Republic of Korea
| | - Jung Pyo Seo
- Department of Physical Medicine and Rehabilitation, College of Medicine, Yeungnam University, Daegu, Republic of Korea
| | - Seung-Hyun Lee
- Robot System Research Division, Daegu Gyeongbuk Institute of Science & Technology, Daegu, Republic of Korea
| | - Sang-Hyun Jin
- Robot System Research Division, Daegu Gyeongbuk Institute of Science & Technology, Daegu, Republic of Korea
| | - Sang Seok Yeo
- Department of Physical Therapy, College of Health Sciences, Dankook University, Cheonan-si, Chungnam, Republic of Korea
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14
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Li J, Zhang XW, Zuo ZT, Lu J, Meng CL, Fang HY, Xue R, Fan Y, Guan YZ, Zhang WH. Cerebral Functional Reorganization in Ischemic Stroke after Repetitive Transcranial Magnetic Stimulation: An fMRI Study. CNS Neurosci Ther 2016; 22:952-960. [PMID: 27421949 DOI: 10.1111/cns.12593] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 06/06/2016] [Accepted: 06/17/2016] [Indexed: 01/13/2023] Open
Abstract
AIMS Our study aimed to figure out brain functional reorganization evidence after repetitive transcranial magnetic stimulation (rTMS) using the resting-state functional magnetic resonance imaging (rsfMRI). METHODS Twelve patients with unilateral subcortex lesion in the middle cerebral artery territory were recruited. Seven of them received a 10-day rTMS treatment beginning at about 5 days after stroke onset. The remaining five received sham treatment. RsfMRI and motor functional scores were obtained before and after rTMS or sham rTMS. RESULTS The rTMS group showed motor recovery according to the behavioral testing scores, while there was no significant difference of motor functional scores in the sham group before and after the sham rTMS. It proved that rTMS facilitates motor recovery of early ischemic stroke patients. Compared with the sham, the rTMS treatment group achieved increased functional connectivity (FC) between ipsilesional M1 and contralesional M1, supplementary motor area, bilateral thalamus, and contralesional postcentral gyrus. And decreased FC was found between ipsilesional M1 and ipsilesional M1, postcentral gyrus and inferior and middle frontal gyrus. CONCLUSION Increased or decreased FC detected by rsfMRI is an important finding to understand the mechanism of brain functional reorganization. The rTMS treatment is a promising therapeutic approach to facilitate motor rehabilitation for early stroke patients.
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Affiliation(s)
- Jing Li
- Department of Radiology, Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medical Sciences, Beijing, China
| | - Xue-Wei Zhang
- Department of Radiology, Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medical Sciences, Beijing, China.,Department of Interventional Radiology, China Meitan General Hospital, Beijing, China
| | - Zhen-Tao Zuo
- State Key Laboratory of Brain and Cognitive Science, Beijing MR Center for Brain Research, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Jie Lu
- Department of Radiology, Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medical Sciences, Beijing, China
| | - Chun-Ling Meng
- Department of Radiology, Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medical Sciences, Beijing, China
| | - Hong-Ying Fang
- Department of Radiology, Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medical Sciences, Beijing, China
| | - Rong Xue
- State Key Laboratory of Brain and Cognitive Science, Beijing MR Center for Brain Research, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Yong Fan
- Department of Radiology, School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yu-Zhou Guan
- Department of Neurology, Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medical Sciences, Beijing, China
| | - Wei-Hong Zhang
- Department of Radiology, Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medical Sciences, Beijing, China
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15
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Basic Principles and Clinical Applications of Magnetic Resonance Spectroscopy in Neuroradiology. J Comput Assist Tomogr 2016; 40:1-13. [PMID: 26484954 DOI: 10.1097/rct.0000000000000322] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Magnetic resonance spectroscopy is a powerful tool to assist daily clinical diagnostics. This review is intended to give an overview on basic principles of the technology, discuss some of its technical aspects, and present typical applications in daily clinical routine in neuroradiology.
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16
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Auriat AM, Neva JL, Peters S, Ferris JK, Boyd LA. A Review of Transcranial Magnetic Stimulation and Multimodal Neuroimaging to Characterize Post-Stroke Neuroplasticity. Front Neurol 2015; 6:226. [PMID: 26579069 PMCID: PMC4625082 DOI: 10.3389/fneur.2015.00226] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 10/12/2015] [Indexed: 01/09/2023] Open
Abstract
Following stroke, the brain undergoes various stages of recovery where the central nervous system can reorganize neural circuitry (neuroplasticity) both spontaneously and with the aid of behavioral rehabilitation and non-invasive brain stimulation. Multiple neuroimaging techniques can characterize common structural and functional stroke-related deficits, and importantly, help predict recovery of function. Diffusion tensor imaging (DTI) typically reveals increased overall diffusivity throughout the brain following stroke, and is capable of indexing the extent of white matter damage. Magnetic resonance spectroscopy (MRS) provides an index of metabolic changes in surviving neural tissue after stroke, serving as a marker of brain function. The neural correlates of altered brain activity after stroke have been demonstrated by abnormal activation of sensorimotor cortices during task performance, and at rest, using functional magnetic resonance imaging (fMRI). Electroencephalography (EEG) has been used to characterize motor dysfunction in terms of increased cortical amplitude in the sensorimotor regions when performing upper limb movement, indicating abnormally increased cognitive effort and planning in individuals with stroke. Transcranial magnetic stimulation (TMS) work reveals changes in ipsilesional and contralesional cortical excitability in the sensorimotor cortices. The severity of motor deficits indexed using TMS has been linked to the magnitude of activity imbalance between the sensorimotor cortices. In this paper, we will provide a narrative review of data from studies utilizing DTI, MRS, fMRI, EEG, and brain stimulation techniques focusing on TMS and its combination with uni- and multimodal neuroimaging methods to assess recovery after stroke. Approaches that delineate the best measures with which to predict or positively alter outcomes will be highlighted.
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Affiliation(s)
- Angela M Auriat
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia , Vancouver, BC , Canada
| | - Jason L Neva
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia , Vancouver, BC , Canada
| | - Sue Peters
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia , Vancouver, BC , Canada
| | - Jennifer K Ferris
- Graduate Program in Neuroscience, Faculty of Medicine, University of British Columbia , Vancouver, BC , Canada
| | - Lara A Boyd
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia , Vancouver, BC , Canada ; Graduate Program in Neuroscience, Faculty of Medicine, University of British Columbia , Vancouver, BC , Canada
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17
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Abstract
Purpose of review Noninvasive brain stimulation (NIBS) is increasingly used to enhance the recovery of function after stroke. The purpose of this review is to highlight and discuss some unresolved questions that need to be addressed to better understand and exploit the potential of NIBS as a therapeutic tool. Recent findings Recent meta-analyses showed that the treatment effects of NIBS in patients with stroke are rather inconsistent across studies and the evidence for therapeutic efficacy is still uncertain. This raises the question of how NIBS can be developed further to improve its therapeutic efficacy. Summary This review addressed six questions: How does NIBS facilitate the recovery of function after stroke? Which brain regions should be targeted by NIBS? Is there a particularly effective NIBS modality that should be used? Does the location of the stroke influence the therapeutic response? How often should NIBS be repeated? Is the functional state of the brain during or before NIBS relevant to therapeutic efficacy of NIBS? We argue that these questions need to be tackled to obtain sufficient mechanistic understanding of how NIBS facilitates the recovery of function. This knowledge will be critical to fully unfold the therapeutic effects of NIBS and will pave the way towards adaptive NIBS protocols, in which NIBS is tailored to the individual patient.
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18
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Cirstea CM, Savage CR, Nudo RJ, Cohen LG, Yeh HW, Choi IY, Lee P, Craciunas SC, Popescu EA, Bani-Ahmed A, Brooks WM. Handgrip-Related Activation in the Primary Motor Cortex Relates to Underlying Neuronal Metabolism After Stroke. Neurorehabil Neural Repair 2013; 28:433-42. [PMID: 24376066 DOI: 10.1177/1545968313516868] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
BACKGROUND Abnormal task-related activation in primary motor cortices (M1) has been consistently found in functional imaging studies of subcortical stroke. Whether the abnormal activations are associated with neuronal alterations in the same or homologous area is not known. OBJECTIVE Our goal was to establish the relationships between M1 measures of motor-task-related activation and a neuronal marker, N-acetylaspartate (NAA), in patients with severe to mild hemiparesis. METHODS A total of 18 survivors of an ischemic subcortical stroke (confirmed on T2-weighted images) at more than six months post-onset and 16 age- and sex-matched right-handed healthy controls underwent functional MRI during a handgrip task (impaired hand in patients, dominant hand in controls) and proton magnetic resonance spectroscopy ((1)H-MRS) imaging. Spatial extent and magnitude of blood oxygen level-dependent response (or activation) and NAA levels were measured in each M1. Relationships between activation and NAA were determined. RESULTS Compared with controls, patients had a greater extent of contralesional (ipsilateral to impaired hand, P < .001) activation and a higher magnitude of activation and lower NAA in both ipsilesional (P = .008 and P < .001, respectively) and contralesional (P < .0001, P < .05) M1. There were significant negative correlations between extent of activation and NAA in each M1 (P = .02) and a trend between contralesional activation and ipsilesional NAA (P = .08) in patients but not in controls. CONCLUSIONS Our results suggest that after stroke greater neuronal recruitment could be a compensatory response to lower neuronal metabolism. Thus, dual-modality imaging may be a powerful tool for providing complementary probes of post-stroke brain reorganization.
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Affiliation(s)
| | - Cary R Savage
- University of Kansas Medical Center, Kansas City, KS, USA
| | | | - Leonardo G Cohen
- National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA
| | - Hung-Wen Yeh
- University of Kansas Medical Center, Kansas City, KS, USA
| | - In-Young Choi
- University of Kansas Medical Center, Kansas City, KS, USA
| | - Phil Lee
- University of Kansas Medical Center, Kansas City, KS, USA
| | | | | | - Ali Bani-Ahmed
- University of Kansas Medical Center, Kansas City, KS, USA
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