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Hutchinson G, Thotland J, Pisharady PK, Garwood M, Lenglet C, Kauppinen RA. T1 relaxation and axon fibre configuration in human white matter. NMR IN BIOMEDICINE 2024; 37:e5234. [PMID: 39097977 PMCID: PMC11639506 DOI: 10.1002/nbm.5234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Revised: 06/18/2024] [Accepted: 07/22/2024] [Indexed: 08/06/2024]
Abstract
Understanding the effects of white matter (WM) axon fibre microstructure on T1 relaxation is important for neuroimaging. Here, we have studied the interrelationship between T1 and axon fibre configurations at 3T and 7T. T1 and S0 (=signal intensity at zero TI) were computed from MP2RAGE images acquired with six inversion recovery times. Multishell diffusion MRI images were analysed for fractional anisotropy (FA); MD; V1; the volume fractions for the first (f1), second (f2) and third (f3) fibre configuration; and fibre density cross-section images for the first (fdc1), second (fdc2) and third (fdc3) fibres. T1 values were plotted as a function of FA, f1, f2, f3, fdc1, fdc2 and fdc3 to examine interrelationships between the longitudinal relaxation and the diffusion MRI microstructural measures. T1 values decreased with increasing FA, f1 and f2 in a nonlinear fashion. At low FA values (from 0.2 to 0.4), a steep shortening of T1 was followed by a shallow shortening by 6%-10% at both fields. The steep shortening was associated with decreasing S0 and MD. T1 also decreased with increasing fdc1 values in a nonlinear fashion. Instead, only a small T1 change as a function of either f3 or fdc3 was observed. In WM areas selected by fdc1 only masks, T1 was shorter than in those with fdc2/fdc3. In WM areas with high single fibre populations, as delineated by f1/fdc1 masks, T1 was shorter than in tissue with high complex fibre configurations, as segmented by f2/fdc2 or f3/fdc3 masks. T1 differences between these WM areas are attributable to combined effects by T1 anisotropy and lowered FA. The current data show strong interrelationships between T1, axon fibre configuration and orientation in healthy WM. It is concluded that diffusion MRI microstructural measures are essential in the effort to interpret quantitative T1 images in terms of tissue state in health and disease.
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Affiliation(s)
- Grace Hutchinson
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, USA
| | - Jeromy Thotland
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, USA
| | - Pramod K. Pisharady
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, USA
| | - Michael Garwood
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, USA
| | - Christophe Lenglet
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, USA
| | - Risto A. Kauppinen
- Department of Electric and Electronic Engineering, University of Bristol, Bristol, UK
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Wan B, Saberi A, Paquola C, Schaare HL, Hettwer MD, Royer J, John A, Dorfschmidt L, Bayrak Ş, Bethlehem RAI, Eickhoff SB, Bernhardt BC, Valk SL. Microstructural asymmetry in the human cortex. Nat Commun 2024; 15:10124. [PMID: 39578424 PMCID: PMC11584796 DOI: 10.1038/s41467-024-54243-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Accepted: 11/01/2024] [Indexed: 11/24/2024] Open
Abstract
The human cerebral cortex shows hemispheric asymmetry, yet the microstructural basis of this asymmetry remains incompletely understood. Here, we probe layer-specific microstructural asymmetry using one post-mortem male brain. Overall, anterior and posterior regions show leftward and rightward asymmetry respectively, but this pattern varies across cortical layers. A similar anterior-posterior pattern is observed using in vivo Human Connectome Project (N = 1101) T1w/T2w microstructural data, with average cortical asymmetry showing the strongest similarity with post-mortem-based asymmetry of layer III. Moreover, microstructural asymmetry is found to be heritable, varies as a function of age and sex, and corresponds to intrinsic functional asymmetry. We also observe a differential association of language and markers of mental health with microstructural asymmetry patterns at the individual level, illustrating a functional divergence between inferior-superior and anterior-posterior microstructural axes, possibly anchored in development. Last, we could show concordant evidence with alternative in vivo microstructural measures: magnetization transfer (N = 286) and quantitative T1 (N = 50). Together, our study highlights microstructural asymmetry in the human cortex and its functional and behavioral relevance.
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Grants
- International Max Planck Research School on Neuroscience of Communication: Function, Structure, and Plasticity (IMPRS NeuroCom), Graduate Academy Leipzig, and Mitacs Globalink Research Award.
- German Ministry for Education and Research (BMBF) and the Max Planck Society
- National Science and Engineering Research Council of Canada (NSERC Discovery-1304413), Canadian Institutes of Health Research (FDN-154298, PJT-174995), SickKids Foundation (NI17-039), BrainCanada, FRQ-S, the Tier-2 Canada Research Chairs program, and Helmholtz International BigBrain Analytics and Learning Laboratory (HIBALL).
- Helmholtz International BigBrain Analytics and Learning Laboratory (HIBALL) and Otto Hahn Award at Max Planck Society.
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Affiliation(s)
- Bin Wan
- Otto Hahn Research Group Cognitive Neurogenetics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
- International Max Planck Research School on Neuroscience of Communication: Function, Structure, and Plasticity (IMPRS NeuroCom), Leipzig, Germany.
- Department of Cognitive Neurology, University Hospital Leipzig and Faculty of Medicine, University of Leipzig, Leipzig, Germany.
- Institute of Neuroscience and Medicine (INM-7: Brain and Behavior), Research Center Jülich, Jülich, Germany.
| | - Amin Saberi
- Otto Hahn Research Group Cognitive Neurogenetics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
- Institute of Neuroscience and Medicine (INM-7: Brain and Behavior), Research Center Jülich, Jülich, Germany
- Institute of Systems Neuroscience, Medical Faculty and University Hospital Düsseldorfpital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Casey Paquola
- Institute of Neuroscience and Medicine (INM-7: Brain and Behavior), Research Center Jülich, Jülich, Germany
| | - H Lina Schaare
- Otto Hahn Research Group Cognitive Neurogenetics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
- Institute of Neuroscience and Medicine (INM-7: Brain and Behavior), Research Center Jülich, Jülich, Germany
| | - Meike D Hettwer
- Otto Hahn Research Group Cognitive Neurogenetics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
- Institute of Neuroscience and Medicine (INM-7: Brain and Behavior), Research Center Jülich, Jülich, Germany
- Institute of Systems Neuroscience, Medical Faculty and University Hospital Düsseldorfpital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Max Planck School of Cognition, Leipzig, Germany
| | - Jessica Royer
- McConnell Brain Imaging Centre, Montréal Neurological Institute and Hospital, McGill University, Montréal, QC, Canada
| | - Alexandra John
- Otto Hahn Research Group Cognitive Neurogenetics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
- Institute of Neuroscience and Medicine (INM-7: Brain and Behavior), Research Center Jülich, Jülich, Germany
| | - Lena Dorfschmidt
- Department of Child and Adolescent Psychiatry and Behavioral Science, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Lifespan Brain Institute, The Children's Hospital of Philadelphia and Penn Medicine, Philadelphia, PA, USA
| | - Şeyma Bayrak
- Otto Hahn Research Group Cognitive Neurogenetics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
- Department of Cognitive Neurology, University Hospital Leipzig and Faculty of Medicine, University of Leipzig, Leipzig, Germany
- Institute of Neuroscience and Medicine (INM-7: Brain and Behavior), Research Center Jülich, Jülich, Germany
| | | | - Simon B Eickhoff
- Institute of Neuroscience and Medicine (INM-7: Brain and Behavior), Research Center Jülich, Jülich, Germany
- Institute of Systems Neuroscience, Medical Faculty and University Hospital Düsseldorfpital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Boris C Bernhardt
- McConnell Brain Imaging Centre, Montréal Neurological Institute and Hospital, McGill University, Montréal, QC, Canada
| | - Sofie L Valk
- Otto Hahn Research Group Cognitive Neurogenetics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
- Institute of Neuroscience and Medicine (INM-7: Brain and Behavior), Research Center Jülich, Jülich, Germany.
- Institute of Systems Neuroscience, Medical Faculty and University Hospital Düsseldorfpital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
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Keegan BM, Absinta M, Cohen-Adad J, Flanagan EP, Henry RG, Klawiter EC, Kolind S, Krieger S, Laule C, Lincoln JA, Messina S, Oh J, Papinutto N, Smith SA, Traboulsee A. Spinal cord evaluation in multiple sclerosis: clinical and radiological associations, present and future. Brain Commun 2024; 6:fcae395. [PMID: 39611182 PMCID: PMC11604059 DOI: 10.1093/braincomms/fcae395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2024] [Revised: 09/30/2024] [Accepted: 11/05/2024] [Indexed: 11/30/2024] Open
Abstract
Spinal cord disease is important in most people with multiple sclerosis, but assessment remains less emphasized in patient care, basic and clinical research and therapeutic trials. The North American Imaging in Multiple Sclerosis Spinal Cord Interest Group was formed to determine and present the contemporary landscape of multiple sclerosis spinal cord evaluation, further existing and advanced spinal cord imaging techniques, and foster collaborative work. Important themes arose: (i) multiple sclerosis spinal cord lesions (differential diagnosis, association with clinical course); (ii) spinal cord radiological-pathological associations; (iii) 'critical' spinal cord lesions; (iv) multiple sclerosis topographical model; (v) spinal cord atrophy; and (vi) automated and special imaging techniques. Distinguishing multiple sclerosis from other myelopathic aetiology is increasingly refined by imaging and serological studies. Post-mortem spinal cord findings and MRI pathological correlative studies demonstrate MRI's high sensitivity in detecting microstructural demyelination and axonal loss. Spinal leptomeninges include immune inflammatory infiltrates, some in B-cell lymphoid-like structures. 'Critical' demyelinating lesions along spinal cord corticospinal tracts are anatomically consistent with and may be disproportionately associated with motor progression. Multiple sclerosis topographical model implicates the spinal cord as an area where threshold impairment associates with multiple sclerosis disability. Progressive spinal cord atrophy and 'silent' multiple sclerosis progression may be emerging as an important multiple sclerosis prognostic biomarker. Manual atrophy assessment is complicated by rater bias, while automation (e.g. Spinal Cord Toolbox), and artificial intelligence may reduce this. Collaborative research by the North American Imaging in Multiple Sclerosis and similar groups with experts combining distinct strengths is key to advancing assessment and treatment of people with multiple sclerosis spinal cord disease.
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Affiliation(s)
- B Mark Keegan
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA
| | - Martina Absinta
- Department of Neurology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Julien Cohen-Adad
- Institute of Biomedical Imaging, Polytechnique Montreal, Montreal, Canada H3T 1J4
| | - Eoin P Flanagan
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA
| | - Roland G Henry
- Department of Neurology, University of California San Francisco, San Francisco, CA 94143, USA
| | - Eric C Klawiter
- Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
| | - Shannon Kolind
- Division of Neurology, University of British Columbia, Vancouver, Canada V6T 2B5
| | - Stephen Krieger
- Department of Neurology, Mount Sinai, New York City, NY 10029, USA
| | - Cornelia Laule
- Division of Neurology, University of British Columbia, Vancouver, Canada V6T 2B5
| | - John A Lincoln
- McGovern Medical School, UTHealth, Houston, TX 77030, USA
| | - Steven Messina
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA
| | - Jiwon Oh
- Division of Neurology, University of Toronto, Toronto, Canada M5B 1W8
| | - Nico Papinutto
- Department of Neurology, University of California San Francisco, San Francisco, CA 94143, USA
| | - Seth Aaron Smith
- Institute of Imaging Science, Vanderbilt University, Nashville, TN 37232, USA
| | - Anthony Traboulsee
- Division of Neurology, University of British Columbia, Vancouver, Canada V6T 2B5
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Agarwal N, Fan A, Huang X, Dehkharghani S, van der Kolk A. ISMRM Clinical Focus Meeting 2023: "Imaging the Fire in the Brain". J Magn Reson Imaging 2024. [PMID: 39193867 DOI: 10.1002/jmri.29587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2024] [Revised: 08/09/2024] [Accepted: 08/11/2024] [Indexed: 08/29/2024] Open
Abstract
Set during the Annual Meeting of the International Society for Magnetic Resonance in Medicine (ISMRM), the "Clinical Focus Meeting" (CFM) aims to bridge the gap between innovative magnetic resonance imaging (MRI) scientific research and daily patient care. This initiative is dedicated to maximizing the impact of MRI technology on healthcare outcomes for patients. At the 2023 Annual Meeting, clinicians and scientists from across the globe were invited to discuss neuroinflammation from various angles (entitled "Imaging the Fire in the Brain"). Topics ranged from fundamental mechanisms and biomarkers of neuroinflammation to the role of different contrast mechanisms, including both proton and non-proton techniques, in brain tumors, autoimmune disorders, and pediatric neuroinflammatory diseases. Discussions also delved into how systemic inflammation can trigger neuroinflammation and the role of the gut-brain axis in causing brain inflammation. Neuroinflammation arises from various external and internal factors and serves as a vital mechanism to mitigate tissue damage and provide neuroprotection. Nonetheless, excessive neuroinflammatory responses can lead to significant tissue injury and subsequent neurological impairments. Prolonged neuroinflammation can result in cellular apoptosis and neurodegeneration, posing severe consequences. MRI can be used to visualize these consequences, by detecting blood-brain barrier damage, characterizing brain lesions, quantifying edema, and identifying specific metabolites. It also facilitates monitoring of chronic changes in both the brain and spinal cord over time, potentially leading to better patient outcomes. This paper represents a summary of the 2023 CFM, and is intended to guide the enthusiastic MR user to several key and novel sequences that MRI offers to image pathophysiologic processes underlying acute and chronic neuroinflammation. EVIDENCE LEVEL: 5 TECHNICAL EFFICACY: Stage 3.
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Affiliation(s)
- Nivedita Agarwal
- Diagnostic Imaging and Neuroradiology Unit, IRCCS Scientific Institute E. Medea, Bosisio Parini, Lecco, Italy
| | - Audrey Fan
- Department of Neurology, University of California Davis Health, Sacramento, California, USA
- Department of Biomedical Engineering, University of California Davis, Davis, California, USA
| | - Xiaoqi Huang
- Department of Radiology and Huaxi MR Research Center (HMRRC), Functional and Molecular Imaging Key Laboratory of Sichuan Province, West China Hospital, Sichuan University, Chengdu, China
| | - Seena Dehkharghani
- Department of Radiology, Albert Einstein College of Medicine-Montefiore Health, New York, New York, USA
| | - Anja van der Kolk
- Department of Medical Imaging, Radboudumc, Nijmegen, The Netherlands
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5
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Yablonskiy DA, Sukstanskii AL. Quantum dipole interactions and transient hydrogen bond orientation order in cells, cellular membranes and myelin sheath: Implications for MRI signal relaxation, anisotropy, and T 1 magnetic field dependence. Magn Reson Med 2024; 91:2597-2611. [PMID: 38241135 PMCID: PMC10997466 DOI: 10.1002/mrm.29996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 12/12/2023] [Accepted: 12/14/2023] [Indexed: 01/21/2024]
Abstract
PURPOSE Despite significant impact on the study of human brain, MRI lacks a theory of signal formation that integrates quantum interactions involving proton dipoles (a primary MRI signal source) with brain intricate cellular environment. The purpose of the present study is developing such a theory. METHODS We introduce the Transient Hydrogen Bond (THB) model, where THB-mediated quantum dipole interactions between water and protons of hydrophilic heads of amphipathic biomolecules forming cells, cellular membranes and myelin sheath serve as a major source of MR signal relaxation. RESULTS The THB theory predicts the existence of a hydrogen-bond-driven structural order of dipole-dipole connections within THBs as a primary factor for the anisotropy observed in MRI signal relaxation. We have also demonstrated that the conventional Lorentzian spectral density function decreases too fast at high frequencies to adequately capture the field dependence of brain MRI signal relaxation. To bridge this gap, we introduced a stretched spectral density function that surpasses the limitations of Lorentzian dispersion. In human brain, our findings reveal that at any time point only about 4% to 7% of water protons are engaged in quantum encounters within THBs. These ultra-short (2 to 3 ns), but frequent quantum spin exchanges lead to gradual recovery of magnetization toward thermodynamic equilibrium, that is, relaxation of MRI signal. CONCLUSION By incorporating quantum proton interactions involved in brain imaging, the THB approach introduces new insights on the complex relationship between brain tissue cellular structure and MRI measurements, thus offering a promising new tool for better understanding of brain microstructure in health and disease.
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Affiliation(s)
- Dmitriy A. Yablonskiy
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, 4525 Scott Ave. Room 3216, St. Louis MO, 63110
- Hope Center for Neurological Disorder, 660 S. Euclid Ave., St. Louis, Missouri 63110
- Knight Alzheimer Disease Research Center, 4488 Forest Park Ave., St. Louis, MO 63108
- Department of Biomedical Engineering, Washington University in St. Louis, 1 Brookings Drive, St. Louis, MO 63130
| | - Alexander L. Sukstanskii
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, 4525 Scott Ave. Room 3216, St. Louis MO, 63110
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6
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Skocic J, Richard L, Ferkul A, Cox E, Tseng J, Laughlin S, Bouffet E, Mabbott DJ. Multimodal imaging with magnetization transfer and diffusion tensor imaging reveals evidence of myelin damage in children and youth treated for a brain tumor. Neurooncol Pract 2024; 11:307-318. [PMID: 38737604 PMCID: PMC11085850 DOI: 10.1093/nop/npae003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2024] Open
Abstract
Background The microstructural damage underlying compromise of white matter following treatment for pediatric brain tumors is unclear. We use multimodal imaging employing advanced diffusion tensor imaging (DTI) and magnetization transfer imaging (MTI) MRI methods to examine chronic microstructural damage to white matter in children and adolescents treated for pediatric brain tumor. Notably, MTI may be more sensitive to macromolecular content, including myelin, than DTI. Methods Fifty patients treated for brain tumors (18 treated with surgery ± chemotherapy and 32 treated with surgery followed by cranial-spinal radiation; time from diagnosis to scan ~6 years) and 45 matched healthy children completed both MTI and DTI scans. Voxelwise and region-of-interest approaches were employed to compare white matter microstructure metrics (magnetization transfer ratio (MTR); DTI- fractional anisotropy [FA], radial diffusivity [RD], axial diffusivity [AD], mean diffusivity [MD]) between patients and healthy controls. Results MTR was decreased across multiple white matter tracts in patients when compared to healthy children, P < .001. These differences were observed for both patients treated with radiation and those treated with only surgery, P < .001. We also found that children and adolescents treated for brain tumors exhibit decreased FA and increased RD/AD/MD compared to their healthy counterparts in several white matter regions, Ps < .02. Finally, we observed that MTR and DTI metrics were related to multiple white matter tracts in patients, Ps < .01, but not healthy control children. Conclusions Our findings provide evidence that the white matter damage observed in patients years after treatment of pediatric posterior fossa tumors, likely reflects myelin disruption.
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Affiliation(s)
- Jovanka Skocic
- Program in Neurosciences and Mental Health, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Logan Richard
- Program in Neurosciences and Mental Health, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Ashley Ferkul
- Program in Neurosciences and Mental Health, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Elizabeth Cox
- Program in Neurosciences and Mental Health, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Psychology, University of Toronto, Toronto, Ontario, Canada
| | - Julie Tseng
- Program in Neurosciences and Mental Health, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Suzanne Laughlin
- Diagnostic Imaging, The Hospital for Sick Children, Toronto, Ontario, Canada
- Medical Imaging, University of Toronto, Toronto, Ontario, Canada
| | - Eric Bouffet
- Division of Haematology/Oncology, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Paediatrics, University of Toronto, Toronto, Ontario, Canada
| | - Donald James Mabbott
- Program in Neurosciences and Mental Health, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Psychology, University of Toronto, Toronto, Ontario, Canada
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Lee CH, Holloman M, Salzer JL, Zhang J. Multi-parametric MRI can detect enhanced myelination in the Gli1 -/- mouse brain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.11.20.567957. [PMID: 38045415 PMCID: PMC10690149 DOI: 10.1101/2023.11.20.567957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
This study investigated the potential of combining multiple MR parameters to enhance the characterization of myelin in the mouse brain. We collected ex vivo multi-parametric MR data at 7 Tesla from control and Gli1 -/- mice; the latter exhibit enhanced myelination at postnatal day 10 (P10) in the corpus callosum and cortex. The MR data included relaxivity, magnetization transfer, and diffusion measurements, each targeting distinct myelin properties. This analysis was followed by and compared to myelin basic protein (MBP) staining of the same samples. Although a majority of the MR parameters included in this study showed significant differences in the corpus callosum between the control and Gli1 -/- mice, only T 2 , T 1 /T 2, and radial diffusivity (RD) demonstrated a significant correlation with MBP values. Based on data from the corpus callosum, partial least square regression suggested that combining T 2 , T 1 /T 2 , and inhomogeneous magnetization transfer ratio could explain approximately 80% of the variance in the MBP values. Myelin predictions based on these three parameters yielded stronger correlations with the MBP values in the P10 mouse brain corpus callosum than any single MR parameter. In the motor cortex, combining T 2 , T 1 /T 2, and radial kurtosis could explain over 90% of the variance in the MBP values at P10. This study demonstrates the utility of multi-parametric MRI in improving the detection of myelin changes in the mouse brain.
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Plank JR, Morgan CA, Smith AK, Sundram F, Hoeh NR, Muthukumaraswamy S, Lin JC. Detection of Neuroinflammation Induced by Typhoid Vaccine Using Quantitative Magnetization Transfer MR: A Randomized Crossover Study. J Magn Reson Imaging 2024; 59:1683-1694. [PMID: 37540052 DOI: 10.1002/jmri.28938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 07/19/2023] [Accepted: 07/20/2023] [Indexed: 08/05/2023] Open
Abstract
BACKGROUND The role of neuroinflammation in psychiatric disorders is not well-elucidated. A noninvasive technique sensitive to low-level neuroinflammation may improve understanding of the pathophysiology of these conditions. PURPOSE To test the ability of quantitative magnetization transfer (QMT) MR at 3 T for detection of low-level neuroinflammation induced by typhoid vaccine within a clinically reasonable scan time. STUDY TYPE Randomized, crossover, placebo-controlled. SUBJECTS Twenty healthy volunteers (10 males; median age 34 years). FIELD STRENGTH/SEQUENCE Magnetization prepared rapid gradient-echo and MT-weighted 3D fast low-angle shot sequences at 3 T. ASSESSMENT Participants were randomized to either vaccine or placebo first with imaging, then after a washout period received the converse with a second set of imaging. MT imaging, scan time, and blood-based inflammatory marker concentrations were assessed pre- and post-vaccine and placebo. Mood was assessed hourly using the Profile of Mood States questionnaire. QMT parameter maps, including the exchange rate from bound to free pool (kba) were generated using a two-pool model and then segmented into tissue type. STATISTICAL TESTS Voxel-wise permutation-based analysis examined inflammatory-related alterations of QMT parameters. The threshold-free cluster enhancement method with family-wise error was used to correct voxel-wise results for multiple comparisons. Region of interest averages were fed into mixed models and Bonferroni corrected. Spearman correlations assessed the relationship between mood scores and QMT parameters. Results were considered significant if corrected P < 0.05. RESULTS Scan time for the MT-weighted acquisition was approximately 11 minutes. Blood-based analysis showed higher IL-6 concentrations post-vaccine compared to post-placebo. Voxel-wise analysis found three clusters indicating an inflammatory-mediated increase in kba in cerebellar white matter. Cerebellar kba for white matter was negatively associated with vigor post-vaccine but not post-placebo. DATA CONCLUSION This study suggested that QMT at 3 T may show some sensitivity to low-level neuroinflammation. Further studies are needed to assess the viability of QMT for use in inflammatory-based disorders. EVIDENCE LEVEL 1 TECHNICAL EFFICACY: Stage 2.
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Affiliation(s)
- Julia R Plank
- School of Pharmacy, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Catherine A Morgan
- Centre for Advanced MRI, Auckland UniServices Limited, Auckland, New Zealand
- School of Psychology and Centre for Brain Research, University of Auckland, Auckland, New Zealand
| | - Alex K Smith
- Wellcome Centre for Integrative Neuroimaging (WIN), Nuffield Department of Clinical Neuroscience, University of Oxford, Oxford, UK
| | - Frederick Sundram
- Department of Psychological Medicine, School of Medicine, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Nicholas R Hoeh
- Department of Psychological Medicine, School of Medicine, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Suresh Muthukumaraswamy
- School of Pharmacy, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Joanne C Lin
- School of Pharmacy, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
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9
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Gloor M, Andelova M, Gaetano L, Papadopoulou A, Burguet Villena F, Sprenger T, Radue EW, Kappos L, Bieri O, Garcia M. Longitudinal analysis of new multiple sclerosis lesions with magnetization transfer and diffusion tensor imaging. Eur Radiol 2024; 34:1680-1691. [PMID: 37658894 PMCID: PMC10873225 DOI: 10.1007/s00330-023-10173-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 07/02/2023] [Accepted: 07/12/2023] [Indexed: 09/05/2023]
Abstract
OBJECTIVE The potential of magnetization transfer imaging (MTI) and diffusion tensor imaging (DTI) for the detection and evolution of new multiple sclerosis (MS) lesions was analyzed. METHODS Nineteen patients with MS obtained conventional MRI, MTI, and DTI examinations bimonthly for 12 months and again after 24 months at 1.5 T MRI. MTI was acquired with balanced steady-state free precession (bSSFP) in 10 min (1.3 mm3 isotropic resolution) yielding both magnetization transfer ratio (MTR) and quantitative magnetization transfer (qMT) parameters (pool size ratio (F), exchange rate (kf), and relaxation times (T1/T2)). DTI provided fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD). RESULTS At the time of their appearance on MRI, the 21 newly detected MS lesions showed significantly reduced MTR/F/kf and prolonged T1/T2 parameters, as well as significantly reduced FA and increased AD/MD/RD. Significant differences were already observed for MTR 4 months and for qMT parameters 2 months prior to lesions' detection on MRI. DTI did not show any significant pre-lesional differences. Slightly reversed trends were observed for most lesions up to 8 months after their detection for qMT and less pronounced for MTR and three diffusion parameters, while appearing unchanged on MRI. CONCLUSIONS MTI provides more information than DTI in MS lesions and detects tissue changes 2 to 4 months prior to their appearance on MRI. After lesions' detection, qMT parameter changes promise to be more sensitive than MTR for the lesions' evolutional assessment. Overall, bSSFP-based MTI adumbrates to be more sensitive than MRI and DTI for the early detection and follow-up assessment of MS lesions. CLINICAL RELEVANCE STATEMENT When additionally acquired in routine MRI, fast bSSFP-based MTI can complement the MRI/DTI longitudinal lesion assessment by detecting MS lesions 2-4 months earlier than with MRI, which could implicate earlier clinical decisions and better follow-up/treatment assessment in MS patients. KEY POINTS • Magnetization transfer imaging provides more information than DTI in multiple sclerosis lesions and can detect tissue changes 2 to 4 months prior to their appearance on MRI. • After lesions' detection, quantitative magnetization transfer changes are more pronounced than magnetization transfer ratio changes and therefore promise to be more sensitive for the lesions' evolutional assessment. • Balanced steady-state free precession-based magnetization transfer imaging is more sensitive than MRI and DTI for the early detection and follow-up assessment of multiple sclerosis lesions.
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Affiliation(s)
- Monika Gloor
- Division of Radiological Physics, Department of Radiology, University Hospital Basel, Basel, Switzerland
| | - Michaela Andelova
- Department of Neurology, University Hospital Basel, Basel, Switzerland
- Department of Neurology and Center of Clinical Neuroscience, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
| | - Laura Gaetano
- Department of Neurology, University Hospital Basel, Basel, Switzerland
- Medical Image Analysis Center (MIAC) AG, Basel, Switzerland
- Novartis Institutes for BioMedical Research Basel, Basel, Switzerland
| | - Athina Papadopoulou
- Department of Neurology, University Hospital Basel, Basel, Switzerland
- Department of Clinical Research, Faculty of Medicine, University Hospital Basel, Basel, Switzerland
| | - Federico Burguet Villena
- Department of Neurology, University Hospital Basel, Basel, Switzerland
- Department of Clinical Research, Faculty of Medicine, University Hospital Basel, Basel, Switzerland
| | - Till Sprenger
- Department of Neurology, University Hospital Basel, Basel, Switzerland
- University Hospital Zürich, Zurich, Switzerland
| | | | - Ludwig Kappos
- Department of Neurology, University Hospital Basel, Basel, Switzerland
- Department of Clinical Research, Faculty of Medicine, University Hospital Basel, Basel, Switzerland
| | - Oliver Bieri
- Division of Radiological Physics, Department of Radiology, University Hospital Basel, Basel, Switzerland
- Department of Biomedical Engineering, University of Basel, Allschwil, Switzerland
| | - Meritxell Garcia
- Division of Neuroradiology, Department of Radiology, University Hospital Basel, Basel, Switzerland.
- Department of Neuroradiology, University Hospital Zürich, Frauenklinikstrasse 10, 8091, Zurich, Switzerland.
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10
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Wallstein N, Müller R, Pampel A, Möller HE. Radiation damping at clinical field strength: Characterization and compensation in quantitative measurements. Magn Reson Med 2024; 91:1239-1253. [PMID: 38010072 DOI: 10.1002/mrm.29934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 10/03/2023] [Accepted: 10/24/2023] [Indexed: 11/29/2023]
Abstract
PURPOSE In any MR experiment, the bulk magnetization acts on itself, caused by the induced current in the RF receiver circuit that generates an oscillating damping field. This effect, known as "radiation damping" (RD), is usually weak and, therefore, unconsidered in MRI, but can affect quantitative studies performed with dedicated coils that provide a high SNR. The current work examined RD in a setup for investigations of small tissue specimens including a quantitative characterization of the spin-coil system. THEORY AND METHODS A custom-made Helmholtz coil (radius and spacing 16 mm) was interfaced to a transmit-receive (Tx/Rx) switch with integrated passive feedback for modulation or suppression of RD similar to preamplifier decoupling. Pulse sequences included pulse-width arrays to demonstrate the absence/ presence of RD and difference techniques employing gradient pulses or composite RF pulses to quantify RD effects during free precession and transmission, respectively. Experiments were performed at 3T in small samples of MnCl2 solution. RESULTS Significant RD effects may impact RF pulse application and evolution periods. Effective damping time constants were comparable to typical T2 * times or echo spacings in multi-echo sequences. Measurements of the phase relation showed that deviations from the commonly assumed 90° angle between the damping field and the transverse magnetization may occur. CONCLUSION Radiation damping may affect the accuracy of quantitative MR measurements performed with dedicated RF coils. Efficient mitigation can be achieved hardware-based or by appropriate consideration in the pulse sequence.
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Affiliation(s)
- Niklas Wallstein
- Nuclear Magnetic Resonance Methods & Development Group, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Roland Müller
- Nuclear Magnetic Resonance Methods & Development Group, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - André Pampel
- Nuclear Magnetic Resonance Methods & Development Group, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Harald E Möller
- Nuclear Magnetic Resonance Methods & Development Group, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
- Faculty of Physics and Earth Sciences, Felix Bloch Institute for Solid State Physics, Leipzig University, Leipzig, Germany
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11
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Heo HY, Singh M, Yedavalli V, Jiang S, Zhou J. CEST and nuclear Overhauser enhancement imaging with deep learning-extrapolated semisolid magnetization transfer reference: Scan-rescan reproducibility and reliability studies. Magn Reson Med 2024; 91:1002-1015. [PMID: 38009996 PMCID: PMC10842109 DOI: 10.1002/mrm.29937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 10/18/2023] [Accepted: 11/04/2023] [Indexed: 11/29/2023]
Abstract
PURPOSE To develop a novel MR physics-driven, deep-learning, extrapolated semisolid magnetization transfer reference (DeepEMR) framework to provide fast, reliable magnetization transfer contrast (MTC) and CEST signal estimations, and to determine the reproducibility and reliability of the estimates from the DeepEMR. METHODS A neural network was designed to predict a direct water saturation and MTC-dominated signal at a certain CEST frequency offset using a few high-frequency offset features in the Z-spectrum. The accuracy, scan-rescan reproducibility, and reliability of MTC, CEST, and relayed nuclear Overhauser enhancement (rNOE) signals estimated from the DeepEMR were evaluated on numerical phantoms and in heathy volunteers at 3 T. In addition, we applied the DeepEMR method to brain tumor patients and compared tissue contrast with other CEST calculation metrics. RESULTS The DeepEMR method demonstrated a high degree of accuracy in the estimation of reference MTC signals at ±3.5 ppm for APT and rNOE imaging, and computational efficiency (˜190-fold) compared with a conventional fitting approach. In addition, the DeepEMR method achieved high reproducibility and reliability (intraclass correlation coefficient = 0.97, intersubject coefficient of variation = 3.5%, and intrasubject coefficient of variation = 1.3%) of the estimation of MTC signals at ±3.5 ppm. In tumor patients, DeepEMR-based amide proton transfer images provided higher tumor contrast than a conventional MT ratio asymmetry image, particularly at higher B1 strengths (>1.5 μT), with a distinct delineation of the tumor core from normal tissue or peritumoral edema. CONCLUSION The DeepEMR approach is feasible for measuring clean APT and rNOE effects in longitudinal and cross-sectional studies with low scan-rescan variability.
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Affiliation(s)
- Hye-Young Heo
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland, USA
| | - Munendra Singh
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland, USA
| | - Vivek Yedavalli
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland, USA
| | - Shanshan Jiang
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland, USA
| | - Jinyuan Zhou
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland, USA
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12
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Foesleitner O, Sturm V, Hayes J, Weiler M, Sam G, Wildemann B, Wick W, Bendszus M, Heiland S, Jäger LB. Microstructural changes of peripheral nerves in early multiple sclerosis: A prospective magnetic resonance neurography study. Eur J Neurol 2024; 31:e16126. [PMID: 37932921 PMCID: PMC11236022 DOI: 10.1111/ene.16126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 10/07/2023] [Accepted: 10/19/2023] [Indexed: 11/08/2023]
Abstract
BACKGROUND AND PURPOSE Multiple sclerosis (MS) is a demyelinating disorder of the central nervous system (CNS). However, there is increasing evidence of peripheral nerve involvement. This study aims to characterize the pattern of peripheral nerve changes in patients with newly diagnosed MS using quantitative magnetic resonance (MR) neurography. METHODS In this prospective study, 25 patients first diagnosed with MS according to the revised McDonald criteria (16 female, mean age = 32.8 ± 10.6 years) and 14 healthy controls were examined with high-resolution 3-T MR neurography of the sciatic nerve using diffusion kurtosis imaging (DKI; 20 diffusional directions, b = 0, 700, 1200 s/mm2 ) and magnetization transfer imaging (MTI). In total, 15 quantitative MR biomarkers were analyzed and correlated with clinical symptoms, intrathecal immunoglobulin synthesis, electrophysiology, and lesion load on brain and spine MR imaging. RESULTS Patients showed decreased fractional anisotropy (mean = 0.51 ± 0.04 vs. 0.56 ± 0.03, p < 0.001), extra-axonal tortuosity (mean = 2.32 ± 0.17 vs. 2.49 ± 0.17, p = 0.008), and radial kurtosis (mean = 1.40 ± 0.23 vs. 1.62 ± 0.23, p = 0.014) and higher radial diffusivity (mean = 1.09 ∙ 10-3 mm2 /s ± 0.16 vs. 0.98 ± 0.11 ∙ 10-3 mm2 /s, p = 0.036) than controls. Groups did not differ in MTI. No significant association was found between MR neurography markers and clinical/laboratory parameters or CNS lesion load. CONCLUSIONS This study provides further evidence of peripheral nerve involvement in MS already at initial diagnosis. The characteristic pattern of DKI parameters indicates predominant demyelination and suggests a primary coaffection of the peripheral nervous system in MS. This first human study using DKI for peripheral nerves shows its potential and clinical feasibility in providing novel biomarkers.
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Affiliation(s)
- Olivia Foesleitner
- Department of NeuroradiologyHeidelberg University HospitalHeidelbergGermany
| | - Volker Sturm
- Department of NeuroradiologyHeidelberg University HospitalHeidelbergGermany
| | - Jennifer Hayes
- Department of NeuroradiologyHeidelberg University HospitalHeidelbergGermany
| | - Markus Weiler
- Department of NeurologyHeidelberg University HospitalHeidelbergGermany
- Clinical Cooperation Unit Neuro‐oncology, German Cancer ConsortiumGerman Cancer Research CenterHeidelbergGermany
| | - Georges Sam
- Department of NeurologyHeidelberg University HospitalHeidelbergGermany
| | | | - Wolfgang Wick
- Department of NeurologyHeidelberg University HospitalHeidelbergGermany
- Clinical Cooperation Unit Neuro‐oncology, German Cancer ConsortiumGerman Cancer Research CenterHeidelbergGermany
| | - Martin Bendszus
- Department of NeuroradiologyHeidelberg University HospitalHeidelbergGermany
| | - Sabine Heiland
- Department of NeuroradiologyHeidelberg University HospitalHeidelbergGermany
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13
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Galgani A, Giorgi FS. Exploring the Role of Locus Coeruleus in Alzheimer's Disease: a Comprehensive Update on MRI Studies and Implications. Curr Neurol Neurosci Rep 2023; 23:925-936. [PMID: 38064152 PMCID: PMC10724305 DOI: 10.1007/s11910-023-01324-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/11/2023] [Indexed: 12/18/2023]
Abstract
PURPOSE OF REVIEW Performing a thorough review of magnetic resonance imaging (MRI) studies assessing locus coeruleus (LC) integrity in ageing and Alzheimer's disease (AD), and contextualizing them with current preclinical and neuropathological literature. RECENT FINDINGS MRI successfully detected LC alterations in ageing and AD, identifying degenerative phenomena involving this nucleus even in the prodromal stages of the disorder. The degree of LC disruption was also associated with the severity of AD cortical pathology, cognitive and behavioral impairment, and the risk of clinical progression. Locus coeruleus-MRI has proved to be a useful tool to assess the integrity of the central noradrenergic system in vivo in humans. It allowed to test in patients preclinical and experimental hypothesis, thus confirming the specific and marked involvement of the LC in AD and its key pathogenetic role. Locus coeruleus-MRI-related data might represent the theoretical basis on which to start developing noradrenergic drugs to target AD.
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Affiliation(s)
- Alessandro Galgani
- Department of Translational Research and of New Surgical and Medical Technologies School of Medicine, University of Pisa, Via Roma 55, 56126, Pisa, Italy
| | - Filippo Sean Giorgi
- Department of Translational Research and of New Surgical and Medical Technologies School of Medicine, University of Pisa, Via Roma 55, 56126, Pisa, Italy.
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14
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Björnholm L, Orell O, Kerkelä M, Honka U, Laasonen S, Riekki T, Surcel HM, Suvanto E, Veijola J. Maternal Thyroid Function During Pregnancy and Offspring White Matter Microstructure in Early Adulthood: A Prospective Birth Cohort Study. Thyroid 2023; 33:1245-1254. [PMID: 37498774 PMCID: PMC10611975 DOI: 10.1089/thy.2022.0699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Background: The fetus is fully dependent on maternal thyroid hormones until mid-gestation and suboptimal maternal thyroid function has been associated with alterations in the neurodevelopment of the offspring. We used maternal free thyroxine (fT4) and thyrotropin (TSH) levels in early gestation to study the association of maternal thyroid function during early pregnancy and offspring brain white matter (WM) integrity in early adulthood. Methods: Our study population consisted of a total of 292 mother-child pairs. Maternal fT4 and TSH were used as predictors and offspring multimodal imaging measures of fractional anisotropy, mean diffusivity, and magnetization transfer ratio (FA, MD, and MTR) as dependent variables. First, as Global analysis, all analyzed 14 WM tracts were studied simultaneously using linear-mixed effect models. Second, if a global effect was detected, a post hoc Tract-wise analysis was carried out using linear models individually in each WM tract. Study population was stratified by sex. Results: We found a positive association between maternal fT4 and offspring Global FA in males when adjusted for all maternal and offspring covariates (n = 114; β = 0.154; confidence interval = 0.045-0.263; p = 0.006). The finding was observed to be driven by multiple WM tracts, of which three projection fiber tracts and the forceps minor survived correcting for multiple comparisons in Tract-wise analysis. Conclusions: Maternal thyroid function in early pregnancy was observed to be associated with WM microstructure in male offspring in early adulthood. Our results suggest that maternal fT4 levels in early pregnancy may modulate axonal characteristics, with a long-term effect on offspring WM development.
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Affiliation(s)
- Lassi Björnholm
- Research Unit of Clinical Medicine, Department of Psychiatry, University of Oulu, Oulu, Finland
- Department of Psychiatry, Oulu University Hospital, Oulu, Finland
- Medical Research Centre Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland
| | - Olavi Orell
- Research Unit of Clinical Medicine, Department of Psychiatry, University of Oulu, Oulu, Finland
| | - Martta Kerkelä
- Research Unit of Clinical Medicine, Department of Psychiatry, University of Oulu, Oulu, Finland
| | - Ulriika Honka
- Research Unit of Health Sciences and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland
| | - Sini Laasonen
- Institute of Biomedicine, University of Eastern Finland, Kuopio, Finland
| | - Tiina Riekki
- Research Unit of Clinical Medicine, Department of Psychiatry, University of Oulu, Oulu, Finland
- Department of Psychiatry, Oulu University Hospital, Oulu, Finland
- Medical Research Centre Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland
| | | | - Eila Suvanto
- Department of Obstetrics and Gynecology, Oulu University Hospital and MRC Oulu University, Oulu, Finland
| | - Juha Veijola
- Research Unit of Clinical Medicine, Department of Psychiatry, University of Oulu, Oulu, Finland
- Department of Psychiatry, Oulu University Hospital, Oulu, Finland
- Medical Research Centre Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland
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15
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Liu W, Wang X, Xie S, Liu WV, Masokano IB, Bai Y, Chen J, Zhong L, Luo Y, Zhou G, Li W, Pei Y. Amide proton transfer (APT) and magnetization transfer (MT) in predicting short-term therapeutic outcome in nasopharyngeal carcinoma after chemoradiotherapy: a feasibility study of three-dimensional chemical exchange saturation transfer (CEST) MRI. Cancer Imaging 2023; 23:80. [PMID: 37658446 PMCID: PMC10474660 DOI: 10.1186/s40644-023-00602-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 08/20/2023] [Indexed: 09/03/2023] Open
Abstract
BACKGROUND The three-dimensional chemical exchange saturation transfer (3D CEST) technique is a novel and promising magnetic resonance sequence; however, its application in nasopharyngeal carcinoma (NPC) lacks sufficient evaluation. This study aimed to assess the feasibility of the 3D CEST technique in predicting the short-term treatment outcomes for chemoradiotherapy (CRT) in NPC patients. METHODS Forty NPC patients and fourteen healthy volunteers were enrolled and underwent the pre-treatment 3D CEST magnetic resonance imaging and diffusion-weighted imaging (DWI). The reliability of 3D CEST was assessed in healthy volunteers by calculating the intra- and inter-observer correlation coefficient (ICC) for amide proton transfer weighted-signal intensity (APTw-SI) and magnetization transfer ratio (MTR) values. NPC patients were divided into residual and non-residual groups based on short-term treatment outcomes after CRT. Whole-tumor regions of interest (ROIs) were manually drawn to measure APTw-SI, MTR and apparent diffusion coefficient (ADC) values. Multivariate analysis and the receiver operating characteristic curve (ROC) were used to evaluate the prediction performance of clinical characteristics, APTw-SI, MTR, ADC values, and combined models in predicting short-term treatment outcomes in NPC patients. RESULTS For the healthy volunteer group, all APTw-SI and MTR values exhibited good to excellent intra- and inter-observer agreements (0.736-0.910, 0.895-0.981, all P > 0.05). For NPC patients, MTR values showed a significant difference between the non-residual and residual groups (31.24 ± 5.21% vs. 34.74 ± 1.54%, P = 0.003) while no significant differences were observed for APTw-SI and ADC values (P > 0.05). Moreover, the diagnostic power of MTR value was superior to APTw-SI (AUC: 0.818 vs. 0.521, P = 0.017) and comparable to ADC values (AUC: 0.818 vs. 0.649, P > 0.05) in predicting short-term treatment outcomes for NPC patients. The prediction performance did not improve even when combining MTR values with APTw-SI and/or ADC values (P > 0.05). CONCLUSIONS The pre-treatment MTR value acquired through 3D CEST demonstrated superior predictive performance for short-term treatment outcomes compared to APTw-SI and ADC values in NPC patients after CRT.
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Affiliation(s)
- Wenguang Liu
- Department of Radiology, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, No.87 Xiangya Rd., Kai Fu District, Changsha, 410008, Hunan, China
| | - Xiao Wang
- Department of Radiology, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, No.87 Xiangya Rd., Kai Fu District, Changsha, 410008, Hunan, China
| | - Simin Xie
- Department of Radiology, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, No.87 Xiangya Rd., Kai Fu District, Changsha, 410008, Hunan, China
| | | | - Ismail Bilal Masokano
- Department of Radiology, The Third Xiangya Hospital, Central South University, Changsha, 410013, Hunan, China
| | - Yu Bai
- Department of Radiology, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, No.87 Xiangya Rd., Kai Fu District, Changsha, 410008, Hunan, China
| | - Juan Chen
- Department of Radiology, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, No.87 Xiangya Rd., Kai Fu District, Changsha, 410008, Hunan, China
| | - Linhui Zhong
- Department of Radiology, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, No.87 Xiangya Rd., Kai Fu District, Changsha, 410008, Hunan, China
| | - Yijing Luo
- Department of Radiology, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, No.87 Xiangya Rd., Kai Fu District, Changsha, 410008, Hunan, China
| | - Gaofeng Zhou
- Department of Radiology, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, No.87 Xiangya Rd., Kai Fu District, Changsha, 410008, Hunan, China
| | - Wenzheng Li
- Department of Radiology, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, No.87 Xiangya Rd., Kai Fu District, Changsha, 410008, Hunan, China.
| | - Yigang Pei
- Department of Radiology, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, No.87 Xiangya Rd., Kai Fu District, Changsha, 410008, Hunan, China.
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16
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Mahmud SZ, Denney TS, Bashir A. Non-contrast estimate of blood-brain barrier permeability in humans using arterial spin labeling and magnetization transfer at 7 T. NMR IN BIOMEDICINE 2023; 36:e4908. [PMID: 36650646 DOI: 10.1002/nbm.4908] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 12/17/2022] [Accepted: 01/16/2023] [Indexed: 06/15/2023]
Abstract
Blood-brain barrier (BBB) dysfunction is associated with a number of central nervous system diseases. This study demonstrates the application of a novel noninvasive technique to measure the BBB permeability in the human brain at 7 T. The technique exploits the fact that, when tissue macromolecules are saturated by off-resonance RF pulse, the intravascular and the extravascular (tissue) water experience different magnetization transfer effects. This principle was combined with arterial spin labeling to distinguish between the intravascular and the tissue water, and was used to calculate perfusion, water extraction fraction (E), and BBB permeability surface area product for water (PS). Simultaneous coregistered magnetization transfer ratio maps were also generated that can provide valuable additional information. Eighteen healthy volunteers (seven females), age = 27 ± 11 years and weight = 65 ± 9 kg, participated in the study. Average perfusion was 67 ± 5 and 29 ± 4 ml/100 g/min (p < 0.05); and E was 0.921 ± 0.025 and 0.962 ± 0.015 (p < 0.05) in the gray matter (GM) and the white matter (WM), respectively. PS was higher in the GM (171 ± 20 ml/100 g/min) compared with the WM (95 ± 18 ml/100 g/min) (p < 0.05). The parameters exhibited good reliability with test re-test experiments. The sensitivity of this technique was demonstrated by 200 mg caffeine intake, which resulted in a decrease in the resting PS by ~31%.
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Affiliation(s)
- Sultan Z Mahmud
- Department of Electrical and Computer Engineering, Auburn University, Auburn, Alabama, USA
- Auburn University MRI Research Center, Auburn University, Auburn, Alabama, USA
| | - Thomas S Denney
- Department of Electrical and Computer Engineering, Auburn University, Auburn, Alabama, USA
- Auburn University MRI Research Center, Auburn University, Auburn, Alabama, USA
| | - Adil Bashir
- Department of Electrical and Computer Engineering, Auburn University, Auburn, Alabama, USA
- Auburn University MRI Research Center, Auburn University, Auburn, Alabama, USA
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17
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Kang B, Singh M, Park H, Heo HY. Only-train-once MR fingerprinting for B 0 and B 1 inhomogeneity correction in quantitative magnetization-transfer contrast. Magn Reson Med 2023; 90:90-102. [PMID: 36883726 PMCID: PMC10149616 DOI: 10.1002/mrm.29629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 02/15/2023] [Accepted: 02/16/2023] [Indexed: 03/09/2023]
Abstract
PURPOSE To develop a fast, deep-learning approach for quantitative magnetization-transfer contrast (MTC)-MR fingerprinting (MRF) that simultaneously estimates multiple tissue parameters and corrects the effects of B0 and B1 variations. METHODS An only-train-once recurrent neural network was designed to perform the fast tissue-parameter quantification for a large range of different MRF acquisition schedules. It enabled a dynamic scan-wise linear calibration of the scan parameters using the measured B0 and B1 maps, which allowed accurate, multiple-tissue parameter mapping. MRF images were acquired from 8 healthy volunteers at 3 T. Estimated parameter maps from the MRF images were used to synthesize the MTC reference signal (Zref ) through Bloch equations at multiple saturation power levels. RESULTS The B0 and B1 errors in MR fingerprints, if not corrected, would impair the tissue quantification and subsequently corrupt the synthesized MTC reference images. Bloch equation-based numerical phantom studies and synthetic MRI analysis demonstrated that the proposed approach could correctly estimate water and semisolid macromolecule parameters, even with severe B0 and B1 inhomogeneities. CONCLUSION The only-train-once deep-learning framework can improve the reconstruction accuracy of brain-tissue parameter maps and be further combined with any conventional MRF or CEST-MRF method.
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Affiliation(s)
- Beomgu Kang
- School of Electrical Engineering, Korea Advanced Institute of Science and Technology, Guseong-dong, Yuseong-gu, Daejeon, Republic of Korea
- Divison of MR Research, Department of Radiology, Johns Hopkins University, Baltimore, Maryland, USA
| | - Munendra Singh
- Divison of MR Research, Department of Radiology, Johns Hopkins University, Baltimore, Maryland, USA
| | - HyunWook Park
- School of Electrical Engineering, Korea Advanced Institute of Science and Technology, Guseong-dong, Yuseong-gu, Daejeon, Republic of Korea
| | - Hye-Young Heo
- Divison of MR Research, Department of Radiology, Johns Hopkins University, Baltimore, Maryland, USA
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18
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Alsop DC, Ercan E, Girard OM, Mackay AL, Michal CA, Varma G, Vinogradov E, Duhamel G. Inhomogeneous magnetization transfer imaging: Concepts and directions for further development. NMR IN BIOMEDICINE 2023; 36:e4808. [PMID: 35916067 DOI: 10.1002/nbm.4808] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 07/27/2022] [Accepted: 07/28/2022] [Indexed: 05/23/2023]
Abstract
Off-resonance radio frequency irradiation can induce the ordering of proton spins in the dipolar fields of their neighbors, in molecules with restricted mobility. This dipolar order decays with a characteristic relaxation time, T1D , that is very different from the T1 and T2 relaxation of the nuclear alignment with the main magnetic field. Inhomogeneous magnetization transfer (ihMT) imaging is a refinement of magnetization transfer (MT) imaging that isolates the MT signal dependence on dipolar order relaxation times within motion-constrained molecules. Because T1D relaxation is a unique contrast mechanism, ihMT may enable improved characterization of tissue. Initial work has stressed the high correlation between ihMT signal and myelin density. Dipolar order relaxation appears to be much longer in membrane lipids than other molecules. Recent work has shown, however, that ihMT acquisitions may also be adjusted to emphasize different ranges of T1D . These newer approaches may be sensitive to other microstructural components of tissue. Here, we review the concepts and history of ihMT and outline the requirements for further development to realize its full potential.
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Affiliation(s)
- David C Alsop
- Department of Radiology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Ece Ercan
- MR Clinical Science, Philips, Best, The Netherlands
| | | | - Alex L Mackay
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Carl A Michal
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Gopal Varma
- Department of Radiology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Elena Vinogradov
- Department of Radiology and Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, Texas, USA
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Mahmud SZ, Denney TS, Bashir A. Feasibility of spinal cord imaging at 7 T using rosette trajectory with magnetization transfer preparation and compressed sensing. Sci Rep 2023; 13:8777. [PMID: 37258697 DOI: 10.1038/s41598-023-35853-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 05/24/2023] [Indexed: 06/02/2023] Open
Abstract
MRI is a valuable diagnostic tool to investigate spinal cord (SC) pathology. SC MRI can benefit from the increased signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) at ultra-high fields such as 7 T. However, SC MRI acquisitions with routine Cartesian readouts are prone to image artifacts caused by physiological motion. MRI acquisition techniques with non-Cartesian readouts such as rosette can help reduce motion artifacts. The purpose of this study was to demonstrate the feasibility of high-resolution SC imaging using rosette trajectory with magnetization transfer preparation (MT-prep) and compressed sensing (CS) at 7 T. Five healthy volunteers participated in the study. Images acquired with rosette readouts demonstrated reduced motion artifacts compared to the standard Cartesian readouts. The combination of multi-echo rosette-readout images improved the CNR by approximately 50% between the gray matter (GM) and white matter (WM) compared to single-echo images. MT-prep images showed excellent contrast between the GM and WM with magnetization transfer ratio (MTR) and cerebrospinal fluid normalized MT signal (MTCSF) = 0.12 ± 0.017 and 0.74 ± 0.013, respectively, for the GM; and 0.18 ± 0.011 and 0.58 ± 0.009, respectively, for the WM. Under-sampled acquisition using rosette readout with CS reconstruction demonstrated up to 6 times faster scans with comparable image quality as the fully-sampled acquisition.
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Affiliation(s)
- Sultan Z Mahmud
- Department of Electrical and Computer Engineering, Auburn University, Auburn, AL, USA
- Auburn University MRI Research Center, Auburn University, Auburn, AL, USA
| | - Thomas S Denney
- Department of Electrical and Computer Engineering, Auburn University, Auburn, AL, USA
- Auburn University MRI Research Center, Auburn University, Auburn, AL, USA
| | - Adil Bashir
- Department of Electrical and Computer Engineering, Auburn University, Auburn, AL, USA.
- Auburn University MRI Research Center, Auburn University, Auburn, AL, USA.
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20
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Stellingwerff MD, Pouwels PJW, Roosendaal SD, Barkhof F, van der Knaap MS. Quantitative MRI in leukodystrophies. Neuroimage Clin 2023; 38:103427. [PMID: 37150021 PMCID: PMC10193020 DOI: 10.1016/j.nicl.2023.103427] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 04/27/2023] [Accepted: 04/28/2023] [Indexed: 05/09/2023]
Abstract
Leukodystrophies constitute a large and heterogeneous group of genetic diseases primarily affecting the white matter of the central nervous system. Different disorders target different white matter structural components. Leukodystrophies are most often progressive and fatal. In recent years, novel therapies are emerging and for an increasing number of leukodystrophies trials are being developed. Objective and quantitative metrics are needed to serve as outcome measures in trials. Quantitative MRI yields information on microstructural properties, such as myelin or axonal content and condition, and on the chemical composition of white matter, in a noninvasive fashion. By providing information on white matter microstructural involvement, quantitative MRI may contribute to the evaluation and monitoring of leukodystrophies. Many distinct MR techniques are available at different stages of development. While some are already clinically applicable, others are less far developed and have only or mainly been applied in healthy subjects. In this review, we explore the background, current status, potential and challenges of available quantitative MR techniques in the context of leukodystrophies.
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Affiliation(s)
- Menno D Stellingwerff
- Amsterdam UMC Location Vrije Universiteit Amsterdam, Child Neurology, Emma Children's Hospital, and Amsterdam Neuroscience, De Boelelaan 1117, Amsterdam, the Netherlands
| | - Petra J W Pouwels
- Amsterdam UMC Location Vrije Universiteit Amsterdam, Department of Radiology and Nuclear Medicine, and Amsterdam Neuroscience, De Boelelaan 1117, Amsterdam, the Netherlands
| | - Stefan D Roosendaal
- Amsterdam UMC Location University of Amsterdam, Department of Radiology, Meibergdreef 9, Amsterdam, the Netherlands
| | - Frederik Barkhof
- Amsterdam UMC Location Vrije Universiteit Amsterdam, Department of Radiology and Nuclear Medicine, and Amsterdam Neuroscience, De Boelelaan 1117, Amsterdam, the Netherlands; University College London, Institutes of Neurology and Healthcare Engineering, London, UK
| | - Marjo S van der Knaap
- Amsterdam UMC Location Vrije Universiteit Amsterdam, Child Neurology, Emma Children's Hospital, and Amsterdam Neuroscience, De Boelelaan 1117, Amsterdam, the Netherlands; Vrije Universiteit Amsterdam, Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, De Boelelaan 1105, Amsterdam, the Netherlands.
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21
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Boonsuth R, Battiston M, Grussu F, Samlidou CM, Calvi A, Samson RS, Gandini Wheeler-Kingshott CAM, Yiannakas MC. Feasibility of in vivo multi-parametric quantitative magnetic resonance imaging of the healthy sciatic nerve with a unified signal readout protocol. Sci Rep 2023; 13:6565. [PMID: 37085693 PMCID: PMC10121559 DOI: 10.1038/s41598-023-33618-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 04/15/2023] [Indexed: 04/23/2023] Open
Abstract
Magnetic resonance neurography (MRN) has been used successfully over the years to investigate the peripheral nervous system (PNS) because it allows early detection and precise localisation of neural tissue damage. However, studies demonstrating the feasibility of combining MRN with multi-parametric quantitative magnetic resonance imaging (qMRI) methods, which provide more specific information related to nerve tissue composition and microstructural organisation, can be invaluable. The translation of emerging qMRI methods previously validated in the central nervous system to the PNS offers real potential to characterise in patients in vivo the underlying pathophysiological mechanisms involved in a plethora of conditions of the PNS. The aim of this study was to assess the feasibility of combining MRN with qMRI to measure diffusion, magnetisation transfer and relaxation properties of the healthy sciatic nerve in vivo using a unified signal readout protocol. The reproducibility of the multi-parametric qMRI protocol as well as normative qMRI measures in the healthy sciatic nerve are reported. The findings presented herein pave the way to the practical implementation of joint MRN-qMRI in future studies of pathological conditions affecting the PNS.
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Affiliation(s)
- Ratthaporn Boonsuth
- NMR Research Unit, Department of Neuroinflammation, Faculty of Brain Sciences, Queen Square MS Centre, UCL Queen Square Institute of Neurology, University College London, London, UK.
- Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand.
| | - Marco Battiston
- NMR Research Unit, Department of Neuroinflammation, Faculty of Brain Sciences, Queen Square MS Centre, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Francesco Grussu
- NMR Research Unit, Department of Neuroinflammation, Faculty of Brain Sciences, Queen Square MS Centre, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Christina Maria Samlidou
- NMR Research Unit, Department of Neuroinflammation, Faculty of Brain Sciences, Queen Square MS Centre, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Alberto Calvi
- NMR Research Unit, Department of Neuroinflammation, Faculty of Brain Sciences, Queen Square MS Centre, UCL Queen Square Institute of Neurology, University College London, London, UK
- Laboratory of Advanced Imaging in Neuroimmunological Diseases, Center of Neuroimmunology, Hospital Clinic Barcelona, Fundació Clinic Per a La Recerca Biomedica, Barcelona, Spain
| | - Rebecca S Samson
- NMR Research Unit, Department of Neuroinflammation, Faculty of Brain Sciences, Queen Square MS Centre, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Claudia A M Gandini Wheeler-Kingshott
- NMR Research Unit, Department of Neuroinflammation, Faculty of Brain Sciences, Queen Square MS Centre, UCL Queen Square Institute of Neurology, University College London, London, UK
- Brain Connectivity Research Centre, IRCCS Mondino Foundation, Pavia, Italy
- Department of Brain and Behavioural Sciences, University of Pavia, Pavia, Italy
| | - Marios C Yiannakas
- NMR Research Unit, Department of Neuroinflammation, Faculty of Brain Sciences, Queen Square MS Centre, UCL Queen Square Institute of Neurology, University College London, London, UK
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22
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Drobyshevsky A, Synowiec S, Goussakov I, Lu J, Gascoigne D, Aksenov DP, Yarnykh V. Temporal trajectories of normal myelination and axonal development assessed by quantitative macromolecular and diffusion MRI: Ultrastructural and immunochemical validation in a rabbit model. Neuroimage 2023; 270:119974. [PMID: 36848973 PMCID: PMC10103444 DOI: 10.1016/j.neuroimage.2023.119974] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 02/15/2023] [Accepted: 02/22/2023] [Indexed: 02/27/2023] Open
Abstract
INTRODUCTION Quantitative and non-invasive measures of brain myelination and maturation during development are of great importance to both clinical and translational research communities. While the metrics derived from diffusion tensor imaging, are sensitive to developmental changes and some pathologies, they remain difficult to relate to the actual microstructure of the brain tissue. The advent of advanced model-based microstructural metrics requires histological validation. The purpose of the study was to validate novel, model-based MRI techniques, such as macromolecular proton fraction mapping (MPF) and neurite orientation and dispersion indexing (NODDI), against histologically derived indexes of myelination and microstructural maturation at various stages of development. METHODS New Zealand White rabbit kits underwent serial in-vivo MRI examination at postnatal days 1, 5, 11, 18, and 25, and as adults. Multi-shell, diffusion-weighted experiments were processed to fit NODDI model to obtain estimates, intracellular volume fraction (ICVF) and orientation dispersion index (ODI). Macromolecular proton fraction (MPF) maps were obtained from three source (MT-, PD-, and T1-weighted) images. After MRI sessions, a subset of animals was euthanized and regional samples of gray and white matter were taken for western blot analysis, to determine myelin basic protein (MBP), and electron microscopy, to estimate axonal, myelin fractions and g-ratio. RESULTS MPF of white matter regions showed a period of fast growth between P5 and P11 in the internal capsule, with a later onset in the corpus callosum. This MPF trajectory was in agreement with levels of myelination in the corresponding brain region, as assessed by western blot and electron microscopy. In the cortex, the greatest increase of MPF occurred between P18 and P26. In contrast, myelin, according to MBP western blot, saw the largest hike between P5 and P11 in the sensorimotor cortex and between P11 and P18 in the frontal cortex, which then seemingly plateaued after P11 and P18 respectively. G-ratio by MRI markers decreased with age in the white matter. However, electron microscopy suggest a relatively stable g-ratio throughout development. CONCLUSION Developmental trajectories of MPF accurately reflected regional differences of myelination rate in different cortical regions and white matter tracts. MRI-derived estimation of g-ratio was inaccurate during early development, likely due to the overestimation of axonal volume fraction by NODDI due to the presence of a large proportion of unmyelinated axons.
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Affiliation(s)
- Alexander Drobyshevsky
- Department of Pediatrics, NorthShore University HealthSystem Research Institute, Evanston, IL, USA.
| | - Sylvia Synowiec
- Department of Pediatrics, NorthShore University HealthSystem Research Institute, Evanston, IL, USA
| | - Ivan Goussakov
- Department of Pediatrics, NorthShore University HealthSystem Research Institute, Evanston, IL, USA
| | - Jing Lu
- Department of Pediatrics, University of Chicago, Chicago, IL, USA
| | - David Gascoigne
- Center for Basic MR Research, NorthShore University HealthSystem Research Institute, Evanston, IL, USA
| | - Daniil P Aksenov
- Center for Basic MR Research, NorthShore University HealthSystem Research Institute, Evanston, IL, USA
| | - Vasily Yarnykh
- Department of Radiology, University of Washington, Seattle, WA, USA
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23
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Lipp I, Kirilina E, Edwards LJ, Pine KJ, Jäger C, Gräßle T, Weiskopf N, Helms G. B 1 + $$ {B}_1^{+} $$ -correction of magnetization transfer saturation maps optimized for 7T postmortem MRI of the brain. Magn Reson Med 2023; 89:1385-1400. [PMID: 36373175 DOI: 10.1002/mrm.29524] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 10/06/2022] [Accepted: 10/25/2022] [Indexed: 11/15/2022]
Abstract
PURPOSE Magnetization transfer saturation ( MTsat $$ \mathrm{MTsat} $$ ) is a useful marker to probe tissue macromolecular content and myelination in the brain. The increased B 1 + $$ {B}_1^{+} $$ -inhomogeneity at ≥ 7 $$ \ge 7 $$ T and significantly larger saturation pulse flip angles which are often used for postmortem studies exceed the limits where previous MTsat $$ \mathrm{MTsat} $$ B 1 + $$ {B}_1^{+} $$ correction methods are applicable. Here, we develop a calibration-based correction model and procedure, and validate and evaluate it in postmortem 7T data of whole chimpanzee brains. THEORY The B 1 + $$ {B}_1^{+} $$ dependence of MTsat $$ \mathrm{MTsat} $$ was investigated by varying the off-resonance saturation pulse flip angle. For the range of saturation pulse flip angles applied in typical experiments on postmortem tissue, the dependence was close to linear. A linear model with a single calibration constant C $$ C $$ is proposed to correct bias in MTsat $$ \mathrm{MTsat} $$ by mapping it to the reference value of the saturation pulse flip angle. METHODS C $$ C $$ was estimated voxel-wise in five postmortem chimpanzee brains. "Individual-based global parameters" were obtained by calculating the mean C $$ C $$ within individual specimen brains and "group-based global parameters" by calculating the means of the individual-based global parameters across the five brains. RESULTS The linear calibration model described the data well, though C $$ C $$ was not entirely independent of the underlying tissue and B 1 + $$ {B}_1^{+} $$ . Individual-based correction parameters and a group-based global correction parameter ( C = 1 . 2 $$ C=1.2 $$ ) led to visible, quantifiable reductions of B 1 + $$ {B}_1^{+} $$ -biases in high-resolution MTsat $$ \mathrm{MTsat} $$ maps. CONCLUSION The presented model and calibration approach effectively corrects for B 1 + $$ {B}_1^{+} $$ inhomogeneities in postmortem 7T data.
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Affiliation(s)
- Ilona Lipp
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Evgeniya Kirilina
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Luke J Edwards
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Kerrin J Pine
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Carsten Jäger
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.,Paul Flechsig Institute of Brain Research, Medical Faculty, Leipzig University, Leipzig, Germany
| | - Tobias Gräßle
- Epidemiology of Highly Pathogenic Microorganisms, Robert Koch-Institute, Berlin, Germany
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- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Nikolaus Weiskopf
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.,Felix Bloch Institute for Solid State Physics, Faculty of Physics and Earth Sciences, Leipzig University, Leipzig, Germany
| | - Gunther Helms
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.,Department of Clinical Sciences and Medical Radiation Physics, Lunds Universitet, Lund, Sweden
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24
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Galgani A, Bartolini E, D’Amora M, Faraguna U, Giorgi FS. The Central Noradrenergic System in Neurodevelopmental Disorders: Merging Experimental and Clinical Evidence. Int J Mol Sci 2023; 24:5805. [PMID: 36982879 PMCID: PMC10055776 DOI: 10.3390/ijms24065805] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 03/15/2023] [Accepted: 03/16/2023] [Indexed: 03/30/2023] Open
Abstract
The aim of this article is to highlight the potential role of the locus-coeruleus-noradrenergic (LC-NA) system in neurodevelopmental disorders (NdDs). The LC is the main brain noradrenergic nucleus, key in the regulation of arousal, attention, and stress response, and its early maturation and sensitivity to perinatal damage make it an interesting target for translational research. Clinical data shows the involvement of the LC-NA system in several NdDs, suggesting a pathogenetic role in the development of such disorders. In this context, a new neuroimaging tool, LC Magnetic Resonance Imaging (MRI), has been developed to visualize the LC in vivo and assess its integrity, which could be a valuable tool for exploring morphological alterations in NdD in vivo in humans. New animal models may be used to test the contribution of the LC-NA system to the pathogenic pathways of NdD and to evaluate the efficacy of NA-targeting drugs. In this narrative review, we provide an overview of how the LC-NA system may represent a common pathophysiological and pathogenic mechanism in NdD and a reliable target for symptomatic and disease-modifying drugs. Further research is needed to fully understand the interplay between the LC-NA system and NdD.
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Affiliation(s)
- Alessandro Galgani
- Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56126 Pisa, Italy; (A.G.)
| | - Emanuele Bartolini
- Department of Developmental Neuroscience, IRCCS Fondazione Stella Maris, 56128 Pisa, Italy
- Tuscany PhD Programme in Neurosciences, 50121 Florence, Italy
| | - Marta D’Amora
- Department of Biology, University of Pisa, 56125 Pisa, Italy
- Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | - Ugo Faraguna
- Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56126 Pisa, Italy; (A.G.)
- Department of Developmental Neuroscience, IRCCS Fondazione Stella Maris, 56128 Pisa, Italy
| | - Filippo Sean Giorgi
- Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, 56126 Pisa, Italy; (A.G.)
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25
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High-resolution magnetization-transfer imaging of post-mortem marmoset brain: Comparisons with relaxometry and histology. Neuroimage 2023; 268:119860. [PMID: 36610679 DOI: 10.1016/j.neuroimage.2023.119860] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 12/28/2022] [Accepted: 01/03/2023] [Indexed: 01/07/2023] Open
Abstract
Cell membranes and macromolecules or paramagnetic compounds interact with water proton spins, which modulates magnetic resonance imaging (MRI) contrast providing information on tissue composition. For a further investigation, quantitative magnetization transfer (qMT) parameters (at 3T), including the ratio of the macromolecular and water proton pools, F, and the exchange-rate constant as well as the (observed) longitudinal and the effective transverse relaxation rates (at 3T and 7T), R1obs and R2*, respectively, were measured at high spatial resolution (200 µm) in a slice of fixed marmoset brain and compared to histology results obtained with Gallyas' myelin stain and Perls' iron stain. R1obs and R2* were linearly correlated with the iron content for the entire slice, whereas distinct differences were obtained between gray and white matter for correlations of relaxometry and qMT parameters with myelin content. The combined results suggest that the macromolecular pool interacting with water consists of myelin and (less efficient) non-myelin contributions. Despite strong correlation of F and R1obs, none of these parameters was uniquely specific to myelination. Due to additional sensitivity to iron stores, R1obs and R2* were more sensitive for depicting microstructural differences between cortical layers than F.
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26
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Paquola C, Hong SJ. The Potential of Myelin-Sensitive Imaging: Redefining Spatiotemporal Patterns of Myeloarchitecture. Biol Psychiatry 2023; 93:442-454. [PMID: 36481065 DOI: 10.1016/j.biopsych.2022.08.031] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 08/12/2022] [Accepted: 08/30/2022] [Indexed: 02/07/2023]
Abstract
Recent advances in magnetic resonance imaging (MRI) have paved the way for approximation of myelin content in vivo. In this review, our main goal was to determine how to best capitalize on myelin-sensitive imaging. First, we briefly overview the theoretical and empirical basis for the myelin sensitivity of different MRI markers and, in doing so, highlight how multimodal imaging approaches are important for enhancing specificity to myelin. Then, we discuss recent studies that have probed the nonuniform distribution of myelin across cortical layers and along white matter tracts. These approaches, collectively known as myelin profiling, have provided detailed depictions of myeloarchitecture in both the postmortem and living human brain. Notably, MRI-based profiling studies have recently focused on investigating whether it can capture interindividual variability in myelin characteristics as well as trajectories across the lifespan. Finally, another line of recent evidence emphasizes the contribution of region-specific myelination to large-scale organization, demonstrating the impact of myelination on global brain networks. In conclusion, we suggest that combining well-validated MRI markers with profiling techniques holds strong potential to elucidate individual differences in myeloarchitecture, which has important implications for understanding brain function and disease.
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Affiliation(s)
- Casey Paquola
- Institute of Neuroscience and Medicine, Forschungszentrum Jülich, Jülich, Germany.
| | - Seok-Jun Hong
- Center for Neuroscience Imaging Research, Institute for Basic Science, Sungkyunkwan University, Suwon, South Korea; Center for the Developing Brain, Child Mind Institute, New York, New York; Department of Biomedical Engineering, Sungkyunkwan University, Suwon, South Korea
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27
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Sukstanskii AL, Yablonskiy DA. Microscopic theory of spin-spin and spin-lattice relaxation of bound protons in cellular and myelin membranes-A lateral diffusion model (LDM). Magn Reson Med 2023; 89:370-383. [PMID: 36094730 PMCID: PMC9826187 DOI: 10.1002/mrm.29430] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 06/26/2022] [Accepted: 08/08/2022] [Indexed: 01/12/2023]
Abstract
PURPOSE Deciphering salient features of biological tissue cellular microstructure in health and diseases is an ultimate goal of MRI. While most MRI approaches are based on studying MR properties of tissue "free" water indirectly affected by tissue microstructure, other approaches, such as magnetization transfer (MT), directly target signals from tissue-forming macromolecules. However, despite three-decades of successful applications, relationships between MT measurements and tissue microstructure remain elusive, hampering interpretation of experimental results. The goal of this paper is to develop microscopic theory connecting the structure of cellular and myelin membranes to their MR properties. THEORY AND METHODS Herein we introduce a lateral diffusion model (LDM) that explains the T2 (spin-spin) and T1 (spin-lattice) MRI relaxation properties of the macromolecular-bound protons by their dipole-dipole interaction modulated by the lateral diffusion of long lipid molecules forming cellular and myelin membranes. RESULTS LDM predicts anisotropic T1 and T2 relaxation of membrane-bound protons. Moreover, their T2 relaxation cannot be described in terms of a standard R2 = 1/T2 relaxation rate parameter, but rather by a relaxation rate function R2 (t) that depends on time t after RF excitation, having, in the main approximation, a logarithmic behavior: R2 (t) ∼ lnt. This anisotropic non-linear relaxation leads to an absorption lineshape that is different from Super-Lorentzian traditionally used in interpreting MT experiments. CONCLUSION LDM-derived analytical equations connect the membrane-bound protons T1 and T2 relaxation with dynamic distances between protons in neighboring membrane-forming lipid molecules and their lateral diffusion. This sheds new light on relationships between MT parameters and microstructure of cellular and myelin membranes.
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28
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Anti-Correlated Myelin-Sensitive MRI Levels in Humans Consistent with a Subcortical to Sensorimotor Regulatory Process-Multi-Cohort Multi-Modal Evidence. Brain Sci 2022; 12:brainsci12121693. [PMID: 36552153 PMCID: PMC9776387 DOI: 10.3390/brainsci12121693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 12/07/2022] [Accepted: 12/07/2022] [Indexed: 12/14/2022] Open
Abstract
Differential axonal myelination synchronises signalling over different axon lengths. The consequences of myelination processes described at the cellular level for the regulation of myelination at the macroscopic level are unknown. We analysed multiple cohorts of myelin-sensitive brain MRI. Our aim was to (i) confirm a previous report of anti-correlation between myelination in subcortical and sensorimotor areas in healthy subjects, (ii) and thereby test our hypothesis for a regulatory interaction between them. We analysed nine image-sets across three different human cohorts using six MRI modalities. Each image-set contained healthy controls (HC) and ME/CFS subjects. Subcortical and Sensorimotor regions of interest (ROI) were optimised for the detection of anti-correlations and the same ROIs were used to test the HC in all image-sets. For each cohort, median MRI values were computed in both regions for each subject and their correlation across the cohort was computed. We confirmed negative correlations in healthy controls between subcortical and sensorimotor regions in six image-sets: three T1wSE (p = 5 × 10-8, 5 × 10-7, 0.002), T2wSE (p =2 × 10-6), MTC (p = 0.01), and WM volume (p = 0.02). T1/T2 was the exception with a positive correlation (p = 0.01). This myelin regulation study is novel in several aspects: human subjects, cross-sectional design, ROI optimization, spin-echo MRI and reproducible across multiple independent image-sets. In multiple independent image-sets we confirmed an anti-correlation between subcortical and sensorimotor myelination which supports a previously unreported regulatory interaction. The subcortical region contained the brain's primary regulatory nuclei. We suggest a mechanism has evolved whereby relatively low subcortical myelination in an individual is compensated by upregulated sensorimotor myelination to maintain adequate sensorimotor performance.
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29
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Wang Y, Zhan M, Roebroeck A, De Weerd P, Kashyap S, Roberts MJ. Inconsistencies in atlas-based volumetric measures of the human nucleus basalis of Meynert: A need for high-resolution alternatives. Neuroimage 2022; 259:119421. [PMID: 35779763 DOI: 10.1016/j.neuroimage.2022.119421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 06/10/2022] [Accepted: 06/28/2022] [Indexed: 10/17/2022] Open
Abstract
The nucleus basalis of Meynert (nbM) is the major source of cortical acetylcholine (ACh) and has been related to cognitive processes and to neurological disorders. However, spatially delineating the human nbM in MRI studies remains challenging. Due to the absence of a functional localiser for the human nbM, studies to date have localised it using nearby neuroanatomical landmarks or using probabilistic atlases. To understand the feasibility of MRI of the nbM we set our four goals; our first goal was to review current human nbM region-of-interest (ROI) selection protocols used in MRI studies, which we found have reported highly variable nbM volume estimates. Our next goal was to quantify and discuss the limitations of existing atlas-based volumetry of nbM. We found that the identified ROI volume depends heavily on the atlas used and on the probabilistic threshold set. In addition, we found large disparities even for data/studies using the same atlas and threshold. To test whether spatial resolution contributes to volume variability, as our third goal, we developed a novel nbM mask based on the normalized BigBrain dataset. We found that as long as the spatial resolution of the target data was 1.3 mm isotropic or above, our novel nbM mask offered realistic and stable volume estimates. Finally, as our last goal we tried to discern nbM using publicly available and novel high resolution structural MRI ex vivo MRI datasets. We find that, using an optimised 9.4T quantitative T2⁎ ex vivo dataset, the nbM can be visualised using MRI. We conclude caution is needed when applying the current methods of mapping nbM, especially for high resolution MRI data. Direct imaging of the nbM appears feasible and would eliminate the problems we identify, although further development is required to allow such imaging using standard (f)MRI scanning.
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Affiliation(s)
- Yawen Wang
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands.
| | - Minye Zhan
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands; U992 (Cognitive neuroimaging unit), NeuroSpin, INSERM-CEA, Gif sur Yvette, France
| | - Alard Roebroeck
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Peter De Weerd
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Sriranga Kashyap
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands; Techna Institute, University Health Network, Toronto, ON, Canada
| | - Mark J Roberts
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands.
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30
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Jara H, Sakai O, Farrher E, Oros-Peusquens AM, Shah NJ, Alsop DC, Keenan KE. Primary Multiparametric Quantitative Brain MRI: State-of-the-Art Relaxometric and Proton Density Mapping Techniques. Radiology 2022; 305:5-18. [PMID: 36040334 PMCID: PMC9524578 DOI: 10.1148/radiol.211519] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 05/01/2022] [Accepted: 05/24/2022] [Indexed: 11/11/2022]
Abstract
This review on brain multiparametric quantitative MRI (MP-qMRI) focuses on the primary subset of quantitative MRI (qMRI) parameters that represent the mobile ("free") and bound ("motion-restricted") proton pools. Such primary parameters are the proton densities, relaxation times, and magnetization transfer parameters. Diffusion qMRI is also included because of its wide implementation in complete clinical MP-qMRI application. MP-qMRI advances were reviewed over the past 2 decades, with substantial progress observed toward accelerating image acquisition and increasing mapping accuracy. Areas that need further investigation and refinement are identified as follows: (a) the biologic underpinnings of qMRI parameter values and their changes with age and/or disease and (b) the theoretical limitations implicitly built into most qMRI mapping algorithms that do not distinguish between the different spatial scales of voxels versus spin packets, the central physical object of the Bloch theory. With rapidly improving image processing techniques and continuous advances in computer hardware, MP-qMRI has the potential for implementation in a wide range of clinical applications. Currently, three emerging MP-qMRI applications are synthetic MRI, macrostructural qMRI, and microstructural tissue modeling.
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Affiliation(s)
- Hernán Jara
- From the Department of Radiology, Boston University, 670 Albany St,
Boston, Mass 02118 (H.J., O.S.); Institute of Neuroscience and Medicine-4,
Forschungszentrum Jülich, Jülich, Germany (E.F., A.M.O.P.,
N.J.S.); Department of Radiology, Beth Israel Deaconess Medical Center, Harvard
Medical School, Boston, Mass (D.C.A.); and Physical Measurement Laboratory,
National Institute of Standards and Technology, Boulder, Colo (K.E.K.)
| | - Osamu Sakai
- From the Department of Radiology, Boston University, 670 Albany St,
Boston, Mass 02118 (H.J., O.S.); Institute of Neuroscience and Medicine-4,
Forschungszentrum Jülich, Jülich, Germany (E.F., A.M.O.P.,
N.J.S.); Department of Radiology, Beth Israel Deaconess Medical Center, Harvard
Medical School, Boston, Mass (D.C.A.); and Physical Measurement Laboratory,
National Institute of Standards and Technology, Boulder, Colo (K.E.K.)
| | - Ezequiel Farrher
- From the Department of Radiology, Boston University, 670 Albany St,
Boston, Mass 02118 (H.J., O.S.); Institute of Neuroscience and Medicine-4,
Forschungszentrum Jülich, Jülich, Germany (E.F., A.M.O.P.,
N.J.S.); Department of Radiology, Beth Israel Deaconess Medical Center, Harvard
Medical School, Boston, Mass (D.C.A.); and Physical Measurement Laboratory,
National Institute of Standards and Technology, Boulder, Colo (K.E.K.)
| | - Ana-Maria Oros-Peusquens
- From the Department of Radiology, Boston University, 670 Albany St,
Boston, Mass 02118 (H.J., O.S.); Institute of Neuroscience and Medicine-4,
Forschungszentrum Jülich, Jülich, Germany (E.F., A.M.O.P.,
N.J.S.); Department of Radiology, Beth Israel Deaconess Medical Center, Harvard
Medical School, Boston, Mass (D.C.A.); and Physical Measurement Laboratory,
National Institute of Standards and Technology, Boulder, Colo (K.E.K.)
| | - N. Jon Shah
- From the Department of Radiology, Boston University, 670 Albany St,
Boston, Mass 02118 (H.J., O.S.); Institute of Neuroscience and Medicine-4,
Forschungszentrum Jülich, Jülich, Germany (E.F., A.M.O.P.,
N.J.S.); Department of Radiology, Beth Israel Deaconess Medical Center, Harvard
Medical School, Boston, Mass (D.C.A.); and Physical Measurement Laboratory,
National Institute of Standards and Technology, Boulder, Colo (K.E.K.)
| | - David C. Alsop
- From the Department of Radiology, Boston University, 670 Albany St,
Boston, Mass 02118 (H.J., O.S.); Institute of Neuroscience and Medicine-4,
Forschungszentrum Jülich, Jülich, Germany (E.F., A.M.O.P.,
N.J.S.); Department of Radiology, Beth Israel Deaconess Medical Center, Harvard
Medical School, Boston, Mass (D.C.A.); and Physical Measurement Laboratory,
National Institute of Standards and Technology, Boulder, Colo (K.E.K.)
| | - Kathryn E. Keenan
- From the Department of Radiology, Boston University, 670 Albany St,
Boston, Mass 02118 (H.J., O.S.); Institute of Neuroscience and Medicine-4,
Forschungszentrum Jülich, Jülich, Germany (E.F., A.M.O.P.,
N.J.S.); Department of Radiology, Beth Israel Deaconess Medical Center, Harvard
Medical School, Boston, Mass (D.C.A.); and Physical Measurement Laboratory,
National Institute of Standards and Technology, Boulder, Colo (K.E.K.)
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31
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Tsili AC, Sofikitis N, Pappa O, Bougia CK, Argyropoulou MI. An Overview of the Role of Multiparametric MRI in the Investigation of Testicular Tumors. Cancers (Basel) 2022; 14:cancers14163912. [PMID: 36010905 PMCID: PMC9405843 DOI: 10.3390/cancers14163912] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 08/07/2022] [Accepted: 08/11/2022] [Indexed: 11/25/2022] Open
Abstract
Simple Summary Although conventional ultrasonography remains the primary imaging modality for the assessment of testicular tumors, multiparametric MRI of the scrotum, which combines morphologic and functional data, serves as a powerful adjunct. Based on the recommendations issued by the Scrotal and Penile Imaging Working Group of the European Society of Urogenital Radiology, scrotal MRI is strongly recommended after equivocal US findings. In cases of testicular masses, the main clinical indications are as follows: lesion characterization when sonographic findings are non-diagnostic, discrimination between germ-cell and non-germ-cell testicular tumors, local staging of testicular tumors in patients who are candidates for testis-sparing surgery, and preoperative histological characterization of testicular germ-cell tumors in selected cases. This article aims to provide an overview of the role of multiparametric MRI in the investigation of testicular tumors. Abstract Conventional ultrasonography represents the mainstay of testis imaging. In cases in which ultrasonography is inconclusive, scrotal MRI using a multiparametric protocol may be used as a useful problem-solving tool. MRI of the scrotum is primarily recommended for differentiating between benign and malignant testicular masses when sonographic findings are ambiguous. This technique is also accurate in the preoperative local staging of testicular tumors and, therefore, is recommended in patients scheduled for testis-sparing surgery. In addition, MRI may provide valuable information regarding the histological characterization of testicular germ-cell tumors, in selected cases. Scrotal MRI may also help in the differentiation between testicular germ-cell neoplasms and non-germ-cell neoplasms. Axial T1-weighted imaging, axial and coronal T2-weighted imaging, axial diffusion-weighted imaging, and coronal subtracted dynamic contrast-enhanced imaging are the minimum requirements for scrotal MRI. A variety of MRI techniques—including diffusion tensor imaging, magnetization transfer imaging, proton MR spectroscopy, volumetric apparent diffusion coefficient histogram analysis, and MRI-based radiomics—are being investigated for testicular mass characterization, providing valuable supplementary diagnostic information. In the present review, we aim to discuss clinical indications for scrotal MRI in cases of testicular tumors, along with MRI findings of common testicular malignancies.
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Affiliation(s)
- Athina C. Tsili
- Department of Clinical Radiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, University Campus, 451 10 Ioannina, Greece
- Correspondence: or
| | - Nikolaos Sofikitis
- Department of Urology, Faculty of Medicine, School of Health Sciences, University of Ioannina, University Campus, 451 10 Ioannina, Greece
| | - Ourania Pappa
- Department of Clinical Radiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, University Campus, 451 10 Ioannina, Greece
| | - Christina K. Bougia
- Department of Clinical Radiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, University Campus, 451 10 Ioannina, Greece
| | - Maria I. Argyropoulou
- Department of Clinical Radiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, University Campus, 451 10 Ioannina, Greece
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32
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Woo A, Botta A, Shi SSW, Paus T, Pausova Z. Obesity-Related Neuroinflammation: Magnetic Resonance and Microscopy Imaging of the Brain. Int J Mol Sci 2022; 23:8790. [PMID: 35955925 PMCID: PMC9368789 DOI: 10.3390/ijms23158790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Revised: 08/03/2022] [Accepted: 08/06/2022] [Indexed: 12/01/2022] Open
Abstract
Obesity is a major risk factor of Alzheimer's disease and related dementias. The principal feature of dementia is a loss of neurons and brain atrophy. The mechanistic links between obesity and the neurodegenerative processes of dementias are not fully understood, but recent research suggests that obesity-related systemic inflammation and subsequent neuroinflammation may be involved. Adipose tissues release multiple proinflammatory molecules (fatty acids and cytokines) that impact blood and vessel cells, inducing low-grade systemic inflammation that can transition to tissues, including the brain. Inflammation in the brain-neuroinflammation-is one of key elements of the pathobiology of neurodegenerative disorders; it is characterized by the activation of microglia, the resident immune cells in the brain, and by the structural and functional changes of other cells forming the brain parenchyma, including neurons. Such cellular changes have been shown in animal models with direct methods, such as confocal microscopy. In humans, cellular changes are less tangible, as only indirect methods such as magnetic resonance (MR) imaging are usually used. In these studies, obesity and low-grade systemic inflammation have been associated with lower volumes of the cerebral gray matter, cortex, and hippocampus, as well as altered tissue MR properties (suggesting microstructural variations in cellular and molecular composition). How these structural variations in the human brain observed using MR imaging relate to the cellular variations in the animal brain seen with microscopy is not well understood. This review describes the current understanding of neuroinflammation in the context of obesity-induced systemic inflammation, and it highlights need for the bridge between animal microscopy and human MR imaging studies.
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Affiliation(s)
- Anita Woo
- The Hospital for Sick Children, University of Toronto, Toronto, ON M5G 1X8, Canada
- Departments of Physiology and Nutritional Sciences, University of Toronto, Toronto, ON M5S 1A1, Canada
| | - Amy Botta
- The Hospital for Sick Children, University of Toronto, Toronto, ON M5G 1X8, Canada
- Departments of Physiology and Nutritional Sciences, University of Toronto, Toronto, ON M5S 1A1, Canada
| | - Sammy S. W. Shi
- The Hospital for Sick Children, University of Toronto, Toronto, ON M5G 1X8, Canada
- Departments of Physiology and Nutritional Sciences, University of Toronto, Toronto, ON M5S 1A1, Canada
| | - Tomas Paus
- Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Montreal, QC H3T 1C5, Canada
- Departments of Psychiatry of Neuroscience, Faculty of Medicine, University of Montreal, Montreal, QC H3T 1J4, Canada
- Departments of Psychology and Psychiatry, University of Toronto, Toronto, ON M5S 1A1, Canada
- ECOGENE-21, Chicoutimi, QC G7H 7K9, Canada
| | - Zdenka Pausova
- The Hospital for Sick Children, University of Toronto, Toronto, ON M5G 1X8, Canada
- Departments of Physiology and Nutritional Sciences, University of Toronto, Toronto, ON M5S 1A1, Canada
- ECOGENE-21, Chicoutimi, QC G7H 7K9, Canada
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33
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Mayar M, Miltenburg JL, Hettinga K, Smeets PAM, van Duynhoven JPM, Terenzi C. Non-invasive monitoring of in vitro gastric milk protein digestion kinetics by 1H NMR magnetization transfer. Food Chem 2022; 383:132545. [PMID: 35255364 DOI: 10.1016/j.foodchem.2022.132545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Revised: 02/19/2022] [Accepted: 02/21/2022] [Indexed: 11/28/2022]
Abstract
Processing of milk involves heating, which can modify the structure and digestibility of its proteins. In vitro models are useful for studying protein digestion. However, validating these models with in vivo data is challenging. Here, we non-invasively monitor in vitro gastric milk protein digestion by protein-water chemical exchange detected by 1H nuclear magnetic resonance (NMR) magnetization transfer (MT). We obtained either a fitted composite exchange rate (CER) with a relative standard error of ≤10% or the MT ratio (MTR) of the intensity without or with an off-resonance saturation pulse, from just a single spectral acquisition. Both CER and MTR, affected by the variation in the amount of semi-solid protons, decreased during in vitro gastric digestion in agreement with standard protein content analyses. The decrease was slower in heated milk, indicating slower breakdown of the coagulum. Our results open the way to future quantification of protein digestion in vivo by MRI.
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Affiliation(s)
- Morwarid Mayar
- Laboratory of Biophysics, Wageningen University, Wageningen, The Netherlands; Division of Human Nutrition and Health, Wageningen University, Wageningen, The Netherlands
| | - Julie L Miltenburg
- Food Quality and Design, Wageningen University, Wageningen, The Netherlands
| | - Kasper Hettinga
- Food Quality and Design, Wageningen University, Wageningen, The Netherlands
| | - Paul A M Smeets
- Division of Human Nutrition and Health, Wageningen University, Wageningen, The Netherlands; Image Sciences Institute, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | | | - Camilla Terenzi
- Laboratory of Biophysics, Wageningen University, Wageningen, The Netherlands
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34
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Del Signore F, Vignoli M, Della Salda L, Tamburro R, Paolini A, Cerasoli I, Chincarini M, Rossi E, Ferri N, Romanucci M, Falerno I, de Pasquale F. A Magnetic Resonance-Relaxometry-Based Technique to Identify Blood Products in Brain Parenchyma: An Experimental Study on a Rabbit Model. Front Vet Sci 2022; 9:802272. [PMID: 35711807 PMCID: PMC9195168 DOI: 10.3389/fvets.2022.802272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 04/11/2022] [Indexed: 11/13/2022] Open
Abstract
Magnetic resonance relaxometry is a quantitative technique that estimates T1/T2 tissue relaxation times. This has been proven to increase MRI diagnostic accuracy of brain disorders in human medicine. However, literature in the veterinary field is scarce. In this work, a T1 and T2-based relaxometry approach has been developed. The aim is to investigate its performance in characterizing subtle brain lesions obtained with autologous blood injections in rabbits. This study was performed with a low-field scanner, typically present in veterinary clinics. The approach consisted of a semi-automatic hierarchical classification of different regions, selected from a T2 map. The classification was driven according to the relaxometry properties extracted from a set of regions selected by the radiologist to compare the suspected lesion with the healthy parenchyma. Histopathological analyses were performed to estimate the performance of the proposed classifier through receiver operating characteristic curve analyses. The classifier resulted in moderate accuracy in terms of lesion characterization.
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Affiliation(s)
- Francesca Del Signore
- Veterinary Faculty, University of Teramo, Teramo, Italy
- *Correspondence: Francesca Del Signore
| | | | | | | | | | | | | | - Emanuela Rossi
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise Giuseppe Caporale, Teramo, Italy
| | - Nicola Ferri
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise Giuseppe Caporale, Teramo, Italy
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35
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Lei D, Suo X, Qin K, Pinaya WHL, Ai Y, Li W, Kuang W, Lui S, Kemp GJ, Sweeney JA, Gong Q. Magnetization transfer imaging alterations and its diagnostic value in antipsychotic-naïve first-episode schizophrenia. Transl Psychiatry 2022; 12:189. [PMID: 35523792 PMCID: PMC9076920 DOI: 10.1038/s41398-022-01939-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 04/15/2022] [Accepted: 04/20/2022] [Indexed: 02/08/2023] Open
Abstract
Magnetization transfer imaging (MTI) may provide more sensitivity and mechanistic understanding of neuropathological changes associated with schizophrenia than volumetric MRI. This study aims to identify brain magnetization transfer ratio (MTR) changes in antipsychotic-naïve first-episode schizophrenia (FES), and to correlate MTR findings with clinical symptom severity. A total of 143 individuals with antipsychotic-naïve FES and 147 healthy controls (HCs) were included and underwent 3.0 T brain MTI between August 2005 and July 2014. Voxelwise analysis was performed to test for MTR differences with family-wise error corrections. Relationships of these differences to symptom severity were assessed using partial correlations. Exploratory analyses using a support vector machine (SVM) classifier were conducted to discriminate FES from HCs using MTR maps. Model performance was examined using a 10-fold stratified cross-validation. Compared with HCs, individuals with FES exhibited higher MTR values in left thalamus, precuneus, cuneus, and paracentral lobule, that were positively correlated with schizophrenia symptom severity [precuneus (r = 0.34, P = 0.0004), cuneus (r = 0.33, P = 0.0006) and paracentral lobule (r = 0.37, P = 0.001)]. Whole-brain MTR maps identified individuals with FES with overall accuracy 75.5% (219 of 290 individuals) based on SVM approach. In antipsychotic-naïve FES, clinically relevant biophysical abnormalities detected by MTI mainly in the left parieto-occipital regions are informative about local brain pathology, and have potential as diagnostic markers.
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Affiliation(s)
- Du Lei
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, 610041, Sichuan, China
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH, 45227, USA
| | - Xueling Suo
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, 610041, Sichuan, China
| | - Kun Qin
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, 610041, Sichuan, China
| | - Walter H L Pinaya
- Department of Biomedical Engineering, School of Biomedical Engineering & Imaging Sciences, King's College London, London, WC2R 2LS, UK
| | - Yuan Ai
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, 610041, Sichuan, China
| | - Wenbin Li
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, 610041, Sichuan, China
| | - Weihong Kuang
- Department of Psychiatry, West China Hospital of Sichuan University, Chengdu, Sichuan, 610041, China
- Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, Chengdu, Sichuan, 610041, China
| | - Su Lui
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, 610041, Sichuan, China
- Functional and Molecular Imaging Key Laboratory of Sichuan Province, West China Hospital of Sichuan University, Chengdu, Sichuan, 610041, China
| | - Graham J Kemp
- Liverpool Magnetic Resonance Imaging Centre (LiMRIC) and Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, L69 3GE, UK
| | - John A Sweeney
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, 610041, Sichuan, China
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH, 45227, USA
| | - Qiyong Gong
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, 610041, Sichuan, China.
- Department of Radiology, West China Xiamen Hospital of Sichuan University, Xiamen, Fujian, 361022, China.
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36
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York EN, Thrippleton MJ, Meijboom R, Hunt DPJ, Waldman AD. Quantitative magnetization transfer imaging in relapsing-remitting multiple sclerosis: a systematic review and meta-analysis. Brain Commun 2022; 4:fcac088. [PMID: 35652121 PMCID: PMC9149789 DOI: 10.1093/braincomms/fcac088] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 12/17/2021] [Accepted: 03/31/2022] [Indexed: 11/28/2022] Open
Abstract
Myelin-sensitive MRI such as magnetization transfer imaging has been widely used in multiple sclerosis. The influence of methodology and differences in disease subtype on imaging findings is, however, not well established. Here, we systematically review magnetization transfer brain imaging findings in relapsing-remitting multiple sclerosis. We examine how methodological differences, disease effects and their interaction influence magnetization transfer imaging measures. Articles published before 06/01/2021 were retrieved from online databases (PubMed, EMBASE and Web of Science) with search terms including 'magnetization transfer' and 'brain' for systematic review, according to a pre-defined protocol. Only studies that used human in vivo quantitative magnetization transfer imaging in adults with relapsing-remitting multiple sclerosis (with or without healthy controls) were included. Additional data from relapsing-remitting multiple sclerosis subjects acquired in other studies comprising mixed disease subtypes were included in meta-analyses. Data including sample size, MRI acquisition protocol parameters, treatments and clinical findings were extracted and qualitatively synthesized. Where possible, effect sizes were calculated for meta-analyses to determine magnetization transfer (i) differences between patients and healthy controls; (ii) longitudinal change and (iii) relationships with clinical disability in relapsing-remitting multiple sclerosis. Eighty-six studies met inclusion criteria. MRI acquisition parameters varied widely, and were also underreported. The majority of studies examined the magnetization transfer ratio in white matter, but magnetization transfer metrics, brain regions examined and results were heterogeneous. The analysis demonstrated a risk of bias due to selective reporting and small sample sizes. The pooled random-effects meta-analysis across all brain compartments revealed magnetization transfer ratio was 1.17 per cent units (95% CI -1.42 to -0.91) lower in relapsing-remitting multiple sclerosis than healthy controls (z-value: -8.99, P < 0.001, 46 studies). Linear mixed-model analysis did not show a significant longitudinal change in magnetization transfer ratio across all brain regions [β = 0.12 (-0.56 to 0.80), t-value = 0.35, P = 0.724, 14 studies] or normal-appearing white matter alone [β = 0.037 (-0.14 to 0.22), t-value = 0.41, P = 0.68, eight studies]. There was a significant negative association between the magnetization transfer ratio and clinical disability, as assessed by the Expanded Disability Status Scale [r = -0.32 (95% CI -0.46 to -0.17); z-value = -4.33, P < 0.001, 13 studies]. Evidence suggests that magnetization transfer imaging metrics are sensitive to pathological brain changes in relapsing-remitting multiple sclerosis, although effect sizes were small in comparison to inter-study variability. Recommendations include: better harmonized magnetization transfer acquisition protocols with detailed methodological reporting standards; larger, well-phenotyped cohorts, including healthy controls; and, further exploration of techniques such as magnetization transfer saturation or inhomogeneous magnetization transfer ratio.
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Affiliation(s)
- Elizabeth N. York
- Centre for Clinical Brain Sciences, University of
Edinburgh, Edinburgh, UK
| | | | - Rozanna Meijboom
- Centre for Clinical Brain Sciences, University of
Edinburgh, Edinburgh, UK
| | - David P. J. Hunt
- Centre for Clinical Brain Sciences, University of
Edinburgh, Edinburgh, UK
- UK Dementia Research Institute, University of
Edinburgh, Edinburgh, UK
- Anne Rowling Regenerative Neurology Clinic,
University of Edinburgh, Edinburgh, UK
| | - Adam D. Waldman
- Centre for Clinical Brain Sciences, University of
Edinburgh, Edinburgh, UK
- UK Dementia Research Institute, University of
Edinburgh, Edinburgh, UK
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37
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Lee CH, Walczak P, Zhang J. Inhomogeneous magnetization transfer MRI of white matter structures in the hypomyelinated shiverer mouse brain. Magn Reson Med 2022; 88:332-340. [PMID: 35344613 DOI: 10.1002/mrm.29207] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 12/31/2021] [Accepted: 02/04/2022] [Indexed: 11/09/2022]
Abstract
PURPOSE Inhomogeneous magnetization transfer (ihMT) MRI is uniquely sensitive to myelin with lipids as a primary source of its contrast. In this study, we investigated whether ihMT can detect white matter structures in the hypomyelinated shiverer mouse brain, a model of dysmyelination. METHODS Conventional MT and ihMT images were acquired from ex vivo Rag2-/- control and shiverer mouse brains at 7T using previously reported optimized saturation parameters. RESULTS ihMT ratio (ihMTR) maps revealed hypomyelinated corpus callosum in the shiverer mouse brain, whereas conventional MT ratio (MTR) maps showed no clear contrast. The ihMTR values of the corpus callosum in the shiverer mice were reduced by approximately 40% compared to controls, but remained significantly higher than the ihMTR values of the cortex. CONCLUSION The finding further confirms ihMT's high myelin specificity and suggests its use as a marker to detect early myelination or myelin repair.
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Affiliation(s)
- Choong Heon Lee
- Center for Biomedical Imaging, Department of Radiology, New York University Langone School of Medicine, New York, NY, USA
| | - Piotr Walczak
- Department of Radiology, University of Maryland, Baltimore, MD, USA
| | - Jiangyang Zhang
- Center for Biomedical Imaging, Department of Radiology, New York University Langone School of Medicine, New York, NY, USA
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38
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Rahman N, Ramnarine J, Xu K, Brown A, Baron CA. Test-Retest Reproducibility of In Vivo Magnetization Transfer Ratio and Saturation Index in Mice at 9.4 Tesla. J Magn Reson Imaging 2022; 56:893-903. [PMID: 35156740 DOI: 10.1002/jmri.28106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 01/29/2022] [Accepted: 01/31/2022] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Magnetization transfer saturation (MTsat) imaging was developed to reduce T1 dependence and improve specificity to myelin, compared to the widely used MT ratio (MTR) approach, while maintaining a feasible scan time. As MTsat imaging is an emerging technique, the reproducibility of MTsat compared to MTR must be evaluated. PURPOSE To assess the test-retest reproducibility of MTR and MTsat in the mouse brain at 9.4 T and calculate sample sizes potentially required to detect effect sizes ranging from 6% to 14%. STUDY TYPE Prospective. SUBJECTS Twelve healthy C57Bl/6 mice. FIELD STRENGTH/SEQUENCE 9.4 T; magnetization transfer imaging using FLASH-3D Gradient Echo; T2-weighted TurboRARE spin echo. ASSESSMENT All mice were scanned at two timepoints (5 days apart). MTR and MTsat maps were analyzed using mean region-of-interest (ROIs: corpus callosum [CC], internal capsule [IC], hippocampus [HC], cortex [CX], and thalamus [TH]), and whole brain voxel-wise analysis. STATISTICAL TESTS Bland-Altman plots were used to assess biases between test-retest measurements. Test-retest reproducibility was evaluated via between and within-subject coefficients of variation (bsCV and wsCV, respectively). Sample sizes required were calculated (significance level: 95%; power: 80%), given effect sizes ranging from 6% to 14%, using both between and within-subject approaches. Results were considered statistically significant at P ≤ 0.05. RESULTS Bland-Altman plots showed negligible biases between test-retest sessions (MTR: 0.0009; MTsat: 0). ROI-based and voxel-wise CVs revealed high reproducibility for both MTR (ROI-bsCV/wsCV: CC-4.5/2.8%; IC-6.1/5.2%; HC-5.7/4.6%; CX-5.1/2.3%; TH-7.4/4.9%) and MTsat (ROI-bsCV/wsCV: CC-6.3/4.8%; IC-7.3/5.1%; HC-9.5/6.4%; CX-6.7/6.5%; TH-7.2/5.3%). With a sample size of 6, changes on the order of 15% could be detected in MTR and MTsat, both between and within subjects, while smaller changes (6%-8%) required sample sizes of 10-15 for MTR, and 15-20 for MTsat. DATA CONCLUSION MTsat exhibited comparable reproducibility to MTR, while providing sensitivity to myelin with less T1 dependence than MTR. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 1.
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Affiliation(s)
- Naila Rahman
- Centre for Functional and Metabolic Mapping (CFMM), Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.,Department of Medical Biophysics, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Jordan Ramnarine
- Centre for Functional and Metabolic Mapping (CFMM), Robarts Research Institute, University of Western Ontario, London, Ontario, Canada
| | - Kathy Xu
- Translational Neuroscience Group, Robarts Research Institute, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Arthur Brown
- Translational Neuroscience Group, Robarts Research Institute, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada.,Department of Anatomy and Cell Biology, University of Western Ontario, London, Ontario, Canada
| | - Corey A Baron
- Centre for Functional and Metabolic Mapping (CFMM), Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.,Department of Medical Biophysics, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
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39
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Kisel AA, Naumova AV, Yarnykh VL. Macromolecular Proton Fraction as a Myelin Biomarker: Principles, Validation, and Applications. Front Neurosci 2022; 16:819912. [PMID: 35221905 PMCID: PMC8863973 DOI: 10.3389/fnins.2022.819912] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 01/17/2022] [Indexed: 12/16/2022] Open
Abstract
Macromolecular proton fraction (MPF) is a quantitative MRI parameter describing the magnetization transfer (MT) effect and defined as a relative amount of protons bound to biological macromolecules with restricted molecular motion, which participate in magnetic cross-relaxation with water protons. MPF attracted significant interest during past decade as a biomarker of myelin. The purpose of this mini review is to provide a brief but comprehensive summary of MPF mapping methods, histological validation studies, and MPF applications in neuroscience. Technically, MPF maps can be obtained using a variety of quantitative MT methods. Some of them enable clinically reasonable scan time and resolution. Recent studies demonstrated the feasibility of MPF mapping using standard clinical MRI pulse sequences, thus substantially enhancing the method availability. A number of studies in animal models demonstrated strong correlations between MPF and histological markers of myelin with a minor influence of potential confounders. Histological studies validated the capability of MPF to monitor both demyelination and re-myelination. Clinical applications of MPF have been mainly focused on multiple sclerosis where this method provided new insights into both white and gray matter pathology. Besides, several studies used MPF to investigate myelin role in other neurological and psychiatric conditions. Another promising area of MPF applications is the brain development studies. MPF demonstrated the capabilities to quantitatively characterize the earliest stage of myelination during prenatal brain maturation and protracted myelin development in adolescence. In summary, MPF mapping provides a technically mature and comprehensively validated myelin imaging technology for various preclinical and clinical neuroscience applications.
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Affiliation(s)
- Alena A. Kisel
- Department of Radiology, University of Washington, Seattle, WA, United States
- Laboratory of Neurobiology, Tomsk State University, Tomsk, Russia
| | - Anna V. Naumova
- Department of Radiology, University of Washington, Seattle, WA, United States
| | - Vasily L. Yarnykh
- Department of Radiology, University of Washington, Seattle, WA, United States
- Laboratory of Neurobiology, Tomsk State University, Tomsk, Russia
- *Correspondence: Vasily L. Yarnykh,
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Coad BM, Ghomroudi PA, Sims R, Aggleton JP, Vann SD, Metzler-Baddeley C. Apolipoprotein ε4 modifies obesity-related atrophy in the hippocampal formation of cognitively healthy adults. Neurobiol Aging 2022; 113:39-54. [PMID: 35303671 PMCID: PMC9084919 DOI: 10.1016/j.neurobiolaging.2022.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 01/18/2022] [Accepted: 02/12/2022] [Indexed: 12/02/2022]
Abstract
Age-related inverted U-shaped curve of hippocampal myelin/neurite packing. Reduced hippocampal myelin/neurite packing and size/complexity in obesity. APOE modifies the effects of obesity on hippocampal size/complexity. Age-related slowing of spatial navigation but no risk effects on cognition. CA/DG predict episodic memory and subiculum predicts spatial navigation performance.
Characterizing age- and risk-related hippocampal vulnerabilities may inform about the neural underpinnings of cognitive decline. We studied the impact of three risk-factors, Apolipoprotein (APOE)-ε4, a family history of dementia, and central obesity, on the CA1, CA2/3, dentate gyrus and subiculum of 158 cognitively healthy adults (38-71 years). Subfields were labelled with the Automatic Segmentation of Hippocampal Subfields and FreeSurfer (version 6) protocols. Volumetric and microstructural measurements from quantitative magnetization transfer and Neurite Orientation Density and Dispersion Imaging were extracted for each subfield and reduced to three principal components capturing apparent myelin/neurite packing, size/complexity, and metabolism. Aging was associated with an inverse U-shaped curve on myelin/neurite packing and affected all subfields. Obesity led to reductions in myelin/neurite packing and size/complexity regardless of APOE and family history of dementia status. However, amongst individuals with a healthy Waist-Hip-Ratio, APOE ε4 carriers showed lower size/complexity than non-carriers. Segmentation protocol type did not affect this risk pattern. These findings reveal interactive effects between APOE and central obesity on the hippocampal formation of cognitively healthy adults.
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West DJ, Cruz G, Teixeira RPAG, Schneider T, Tournier JD, Hajnal JV, Prieto C, Malik SJ. An MR fingerprinting approach for quantitative inhomogeneous magnetization transfer imaging. Magn Reson Med 2022; 87:220-235. [PMID: 34418151 PMCID: PMC7614010 DOI: 10.1002/mrm.28984] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 07/15/2021] [Accepted: 08/05/2021] [Indexed: 01/07/2023]
Abstract
PURPOSE Magnetization transfer (MT) and inhomogeneous MT (ihMT) contrasts are used in MRI to provide information about macromolecular tissue content. In particular, MT is sensitive to macromolecules, and ihMT appears to be specific to myelinated tissue. This study proposes a technique to characterize MT and ihMT properties from a single acquisition, producing both semiquantitative contrast ratios and quantitative parameter maps. THEORY AND METHODS Building on previous work that uses multiband RF pulses to efficiently generate ihMT contrast, we propose a cyclic steady-state approach that cycles between multiband and single-band pulses to boost the achieved contrast. Resultant time-variable signals are reminiscent of an MR fingerprinting acquisition, except that the signal fluctuations are entirely mediated by MT effects. A dictionary-based low-rank inversion method is used to reconstruct the resulting images and to produce both semiquantitative MT ratio and ihMT ratio maps, as well as quantitative parameter estimates corresponding to an ihMT tissue model. RESULTS Phantom and in vivo brain data acquired at 1.5 Tesla demonstrate the expected contrast trends, with ihMT ratio maps showing contrast more specific to white matter, as has been reported by others. Quantitative estimation of semisolid fraction and dipolar T1 was also possible and yielded measurements consistent with literature values in the brain. CONCLUSION By cycling between multiband and single-band pulses, an entirely MT-mediated fingerprinting method was demonstrated. This proof-of-concept approach can be used to generate semiquantitative maps and quantitatively estimate some macromolecular-specific tissue parameters.
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Affiliation(s)
- Daniel J. West
- Department of Biomedical Engineering, School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom
| | - Gastao Cruz
- Department of Biomedical Engineering, School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom
| | - Rui P. A. G. Teixeira
- Department of Biomedical Engineering, School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom,Centre for the Developing Brain, School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom
| | | | - Jacques-Donald Tournier
- Department of Biomedical Engineering, School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom,Centre for the Developing Brain, School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom
| | - Joseph V. Hajnal
- Department of Biomedical Engineering, School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom,Centre for the Developing Brain, School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom
| | - Claudia Prieto
- Department of Biomedical Engineering, School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom
| | - Shaihan J. Malik
- Department of Biomedical Engineering, School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom,Centre for the Developing Brain, School of Biomedical Engineering and Imaging Sciences, King’s College London, St. Thomas’ Hospital, London, United Kingdom
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Duan W, Sehrawat P, Zhou TD, Becker JT, Lopez OL, Gach HM, Dai W. Pattern of Altered Magnetization Transfer Rate in Alzheimer's Disease. J Alzheimers Dis 2022; 88:693-705. [PMID: 35694929 PMCID: PMC9382719 DOI: 10.3233/jad-220335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Biomarkers for Alzheimer's disease (AD) are crucial for early diagnosis and treatment monitoring once disease modifying therapies become available. OBJECTIVE This study aims to quantify the forward magnetization transfer rate (kfor) map from brain tissue water to macromolecular protons and use it to identify the brain regions with abnormal kfor in AD and AD progression. METHODS From the Cardiovascular Health Study (CHS) cognition study, magnetization transfer imaging (MTI) was acquired at baseline from 63 participants, including 20 normal controls (NC), 18 with mild cognitive impairment (MCI), and 25 AD subjects. Of those, 53 participants completed a follow-up MRI scan and were divided into four groups: 15 stable NC, 12 NC-to-MCI, 12 stable MCI, and 14 MCI/AD-to-AD subjects. kfor maps were compared across NC, MCI, and AD groups at baseline for the cross-sectional study and across four longitudinal groups for the longitudinal study. RESULTS We found a lower kfor in the frontal gray matter (GM), parietal GM, frontal corona radiata (CR) white matter (WM) tracts, frontal and parietal superior longitudinal fasciculus (SLF) WM tracts in AD relative to both NC and MCI. Further, we observed progressive decreases of kfor in the frontal GM, parietal GM, frontal and parietal CR WM tracts, and parietal SLF WM tracts in stable MCI. In the parietal GM, parietal CR WM tracts, and parietal SLF WM tracts, we found trend differences between MCI/AD-to-AD and stable NC. CONCLUSION Forward magnetization transfer rate is a promising biomarker for AD diagnosis and progression.
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Affiliation(s)
- Wenna Duan
- Department of Computer Science, State University of New York at Binghamton, Binghamton, NY
| | - Parshant Sehrawat
- Department of Computer Science, State University of New York at Binghamton, Binghamton, NY
| | - Tony D. Zhou
- Departments of Radiation Oncology, Radiology, and Biomedical Engineering, Washington University in St. Louis, Saint Louis, MO
| | - James T. Becker
- Department of Psychology, University of Pittsburgh, Pittsburgh, PA
- Department of Psychiatry and Neurology, University of Pittsburgh, Pittsburgh, PA
| | - Oscar L. Lopez
- Department of Psychiatry and Neurology, University of Pittsburgh, Pittsburgh, PA
| | - H. Michael Gach
- Departments of Radiation Oncology, Radiology, and Biomedical Engineering, Washington University in St. Louis, Saint Louis, MO
| | - Weiying Dai
- Department of Computer Science, State University of New York at Binghamton, Binghamton, NY
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Orzyłowska A, Oakden W. Saturation Transfer MRI for Detection of Metabolic and Microstructural Impairments Underlying Neurodegeneration in Alzheimer's Disease. Brain Sci 2021; 12:53. [PMID: 35053797 PMCID: PMC8773856 DOI: 10.3390/brainsci12010053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 12/21/2021] [Accepted: 12/25/2021] [Indexed: 01/08/2023] Open
Abstract
Alzheimer's disease (AD) is one of the most common causes of dementia and difficult to study as the pool of subjects is highly heterogeneous. Saturation transfer (ST) magnetic resonance imaging (MRI) methods are quantitative modalities with potential for non-invasive identification and tracking of various aspects of AD pathology. In this review we cover ST-MRI studies in both humans and animal models of AD over the past 20 years. A number of magnetization transfer (MT) studies have shown promising results in human brain. Increased computing power enables more quantitative MT studies, while access to higher magnetic fields improves the specificity of chemical exchange saturation transfer (CEST) techniques. While much work remains to be done, results so far are very encouraging. MT is sensitive to patterns of AD-related pathological changes, improving differential diagnosis, and CEST is sensitive to particular pathological processes which could greatly assist in the development and monitoring of therapeutic treatments of this currently incurable disease.
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Affiliation(s)
- Anna Orzyłowska
- Department of Neurosurgery and Paediatric Neurosurgery, Medical University of Lublin, Jaczewskiego 8 (SPSK 4), 20-090 Lublin, Poland
| | - Wendy Oakden
- Physical Sciences, Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada;
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Martins D, Giacomel A, Williams SCR, Turkheimer F, Dipasquale O, Veronese M. Imaging transcriptomics: Convergent cellular, transcriptomic, and molecular neuroimaging signatures in the healthy adult human brain. Cell Rep 2021; 37:110173. [PMID: 34965413 DOI: 10.1016/j.celrep.2021.110173] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 09/30/2021] [Accepted: 12/03/2021] [Indexed: 12/12/2022] Open
Abstract
The integration of transcriptomic and neuroimaging data, "imaging transcriptomics," has recently emerged to generate hypotheses about potential biological pathways underlying regional variability in neuroimaging features. However, the validity of this approach is yet to be examined in depth. Here, we sought to bridge this gap by performing transcriptomic decoding of the regional distribution of well-known molecular markers spanning different elements of the biology of the healthy human brain. Imaging transcriptomics identifies biological and cell pathways that are consistent with the known biology of a wide range of molecular neuroimaging markers. The extent to which it can capture patterns of gene expression that align well with elements of the biology of the neuroinflammatory axis, at least in healthy controls without a proinflammatory challenge, is inconclusive. Imaging transcriptomics might constitute an interesting approach to improve our understanding of the biological pathways underlying regional variability in a wide range of neuroimaging phenotypes.
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Affiliation(s)
- Daniel Martins
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, London SE5 8AF, UK.
| | - Alessio Giacomel
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, London SE5 8AF, UK
| | - Steven C R Williams
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, London SE5 8AF, UK
| | - Federico Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, London SE5 8AF, UK
| | - Ottavia Dipasquale
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, London SE5 8AF, UK
| | - Mattia Veronese
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, London SE5 8AF, UK; Department of Information Engineering, University of Padua, Via Gradenigo, 6/b, 35131 Padova, Italy.
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Cottaar M, Wu W, Tendler BC, Nagy Z, Miller K, Jbabdi S. Quantifying myelin in crossing fibers using diffusion-prepared phase imaging: Theory and simulations. Magn Reson Med 2021; 86:2618-2634. [PMID: 34254349 PMCID: PMC8581995 DOI: 10.1002/mrm.28907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 06/03/2021] [Accepted: 06/08/2021] [Indexed: 11/24/2022]
Abstract
PURPOSE Myelin has long been the target of neuroimaging research. However, most available techniques can only provide a voxel-averaged estimate of myelin content. In the human brain, white matter fiber pathways connecting different brain areas and carrying different functions often cross each other in the same voxel. A measure that can differentiate the degree of myelination of crossing fibers would provide a more specific marker of myelination. THEORY AND METHODS One MRI signal property that is sensitive to myelin is the phase accumulation. This sensitivity is used by measuring the phase accumulation of the signal remaining after diffusion-weighting, which is called diffusion-prepared phase imaging (DIPPI). Including diffusion-weighting before estimating the phase accumulation has two distinct advantages for estimating the degree of myelination: (1) It increases the relative contribution of intra-axonal water, whose phase is related linearly to the thickness of the surrounding myelin (in particular the log g-ratio); and (2) it gives directional information, which can be used to distinguish between crossing fibers. Here the DIPPI sequence is described, an approach is proposed to estimate the log g-ratio, and simulations are used and DIPPI data acquired in an isotropic phantom to quantify other sources of phase accumulation. RESULTS The expected bias is estimated in the log g-ratio for reasonable in vivo acquisition parameters caused by eddy currents (~4%-10%), remaining extra-axonal signal (~15%), and gradients in the bulk off-resonance field (<10% for most of the brain). CONCLUSION This new sequence may provide a g-ratio estimate per fiber population crossing within a voxel.
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Affiliation(s)
- Michiel Cottaar
- Wellcome Centre for Integrative Neuroimaging—Centre for Functional Magnetic Resonance Imaging of the BrainJohn Radcliffe HospitalUniversity of OxfordOxfordUnited Kingdom
| | - Wenchuan Wu
- Wellcome Centre for Integrative Neuroimaging—Centre for Functional Magnetic Resonance Imaging of the BrainJohn Radcliffe HospitalUniversity of OxfordOxfordUnited Kingdom
| | - Benjamin C. Tendler
- Wellcome Centre for Integrative Neuroimaging—Centre for Functional Magnetic Resonance Imaging of the BrainJohn Radcliffe HospitalUniversity of OxfordOxfordUnited Kingdom
| | - Zoltan Nagy
- Laboratory for Social and Neural Systems ResearchUniversity of ZurichZurichSwitzerland
| | - Karla Miller
- Wellcome Centre for Integrative Neuroimaging—Centre for Functional Magnetic Resonance Imaging of the BrainJohn Radcliffe HospitalUniversity of OxfordOxfordUnited Kingdom
| | - Saad Jbabdi
- Wellcome Centre for Integrative Neuroimaging—Centre for Functional Magnetic Resonance Imaging of the BrainJohn Radcliffe HospitalUniversity of OxfordOxfordUnited Kingdom
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MacDonald ME, Pike GB. MRI of healthy brain aging: A review. NMR IN BIOMEDICINE 2021; 34:e4564. [PMID: 34096114 DOI: 10.1002/nbm.4564] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 05/08/2021] [Accepted: 05/11/2021] [Indexed: 06/12/2023]
Abstract
We present a review of the characterization of healthy brain aging using MRI with an emphasis on morphology, lesions, and quantitative MR parameters. A scope review found 6612 articles encompassing the keywords "Brain Aging" and "Magnetic Resonance"; papers involving functional MRI or not involving imaging of healthy human brain aging were discarded, leaving 2246 articles. We first consider some of the biogerontological mechanisms of aging, and the consequences of aging in terms of cognition and onset of disease. Morphological changes with aging are reviewed for the whole brain, cerebral cortex, white matter, subcortical gray matter, and other individual structures. In general, volume and cortical thickness decline with age, beginning in mid-life. Prevalent silent lesions such as white matter hyperintensities, microbleeds, and lacunar infarcts are also observed with increasing frequency. The literature regarding quantitative MR parameter changes includes T1 , T2 , T2 *, magnetic susceptibility, spectroscopy, magnetization transfer, diffusion, and blood flow. We summarize the findings on how each of these parameters varies with aging. Finally, we examine how the aforementioned techniques have been used for age prediction. While relatively large in scope, we present a comprehensive review that should provide the reader with sound understanding of what MRI has been able to tell us about how the healthy brain ages.
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Affiliation(s)
- M Ethan MacDonald
- Department of Electrical and Software Engineering, University of Calgary, Calgary, Alberta, Canada
- Departments of Radiology and Clinical Neuroscience, University of Calgary, Calgary, Alberta, Canada
- Healthy Brain Aging Laboratory, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - G Bruce Pike
- Departments of Radiology and Clinical Neuroscience, University of Calgary, Calgary, Alberta, Canada
- Healthy Brain Aging Laboratory, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
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Norbom LB, Ferschmann L, Parker N, Agartz I, Andreassen OA, Paus T, Westlye LT, Tamnes CK. New insights into the dynamic development of the cerebral cortex in childhood and adolescence: Integrating macro- and microstructural MRI findings. Prog Neurobiol 2021; 204:102109. [PMID: 34147583 DOI: 10.1016/j.pneurobio.2021.102109] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 04/26/2021] [Accepted: 06/15/2021] [Indexed: 12/11/2022]
Abstract
Through dynamic transactional processes between genetic and environmental factors, childhood and adolescence involve reorganization and optimization of the cerebral cortex. The cortex and its development plays a crucial role for prototypical human cognitive abilities. At the same time, many common mental disorders appear during these critical phases of neurodevelopment. Magnetic resonance imaging (MRI) can indirectly capture several multifaceted changes of cortical macro- and microstructure, of high relevance to further our understanding of the neural foundation of cognition and mental health. Great progress has been made recently in mapping the typical development of cortical morphology. Moreover, newer less explored MRI signal intensity and specialized quantitative T2 measures have been applied to assess microstructural cortical development. We review recent findings of typical postnatal macro- and microstructural development of the cerebral cortex from early childhood to young adulthood. We cover studies of cortical volume, thickness, area, gyrification, T1-weighted (T1w) tissue contrasts such a grey/white matter contrast, T1w/T2w ratio, magnetization transfer and myelin water fraction. Finally, we integrate imaging studies with cortical gene expression findings to further our understanding of the underlying neurobiology of the developmental changes, bridging the gap between ex vivo histological- and in vivo MRI studies.
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Affiliation(s)
- Linn B Norbom
- NORMENT, Institute of Clinical Medicine, University of Oslo, Norway; PROMENTA Research Center, Department of Psychology, University of Oslo, Norway; Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway.
| | - Lia Ferschmann
- PROMENTA Research Center, Department of Psychology, University of Oslo, Norway
| | - Nadine Parker
- Institute of Medical Science, University of Toronto, Ontario, Canada
| | - Ingrid Agartz
- NORMENT, Institute of Clinical Medicine, University of Oslo, Norway; Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway; K.G Jebsen Center for Neurodevelopmental Disorders, University of Oslo, Norway
| | - Ole A Andreassen
- K.G Jebsen Center for Neurodevelopmental Disorders, University of Oslo, Norway; NORMENT, Division of Mental Health and Addiction, Oslo University Hospital & Institute of Clinical Medicine, University of Oslo, Norway
| | - Tomáš Paus
- ECOGENE-21, Chicoutimi, Quebec, Canada; Department of Psychology and Psychiatry, University of Toronto, Ontario, Canada; Department of Psychiatry and Centre hospitalier universitaire Sainte-Justine, University of Montreal, Canada
| | - Lars T Westlye
- K.G Jebsen Center for Neurodevelopmental Disorders, University of Oslo, Norway; NORMENT, Division of Mental Health and Addiction, Oslo University Hospital & Institute of Clinical Medicine, University of Oslo, Norway; Department of Psychology, University of Oslo, Norway
| | - Christian K Tamnes
- NORMENT, Institute of Clinical Medicine, University of Oslo, Norway; PROMENTA Research Center, Department of Psychology, University of Oslo, Norway; Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway.
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Hédouin R, Metere R, Chan KS, Licht C, Mollink J, van Walsum AMC, Marques JP. Decoding the microstructural properties of white matter using realistic models. Neuroimage 2021; 237:118138. [PMID: 33964461 DOI: 10.1016/j.neuroimage.2021.118138] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 04/14/2021] [Accepted: 04/19/2021] [Indexed: 11/24/2022] Open
Abstract
Multi-echo gradient echo (ME-GRE) magnetic resonance signal evolution in white matter has a strong dependence on the orientation of myelinated axons with respect to the main static field. Although analytical solutions have been able to predict some of the white matter (WM) signal behaviour of the hollow cylinder model, it has been shown that realistic models of WM offer a better description of the signal behaviour observed. In this work, we present a pipeline to (i) generate realistic 2D WM models with their microstructure based on real axon morphology with adjustable fiber volume fraction (FVF) and g-ratio. We (ii) simulate their interaction with the static magnetic field to be able to simulate their MR signal. For the first time, we (iii) demonstrate that realistic 2D WM models can be used to simulate a MR signal that provides a good approximation of the signal obtained from a real 3D WM model derived from electron microscopy. We then (iv) demonstrate in silico that 2D WM models can be used to predict microstructural parameters in a robust way if ME-GRE multi-orientation data is available and the main fiber orientation in each pixel is known using DTI. A deep learning network was trained and characterized in its ability to recover the desired microstructural parameters such as FVF, g-ratio, free and bound water transverse relaxation and magnetic susceptibility. Finally, the network was trained to recover these micro-structural parameters from an ex vivo dataset acquired in 9 orientations with respect to the magnetic field and 12 echo times. We demonstrate that this is an overdetermined problem and that as few as 3 orientations can already provide comparable results for some of the decoded metrics.
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Affiliation(s)
- Renaud Hédouin
- Radboud University, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, Netherlands; Empenn, INRIA, INSERM, CNRS, Université de Rennes 1, Rennes, France.
| | - Riccardo Metere
- Radboud University, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, Netherlands
| | - Kwok-Shing Chan
- Radboud University, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, Netherlands
| | - Christian Licht
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Germany
| | - Jeroen Mollink
- Radboud University Medical Centre, Medical Imaging and Anatomy, Nijmegen, Netherlands
| | | | - José P Marques
- Radboud University, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, Netherlands
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Biel D, Steiger TK, Bunzeck N. Age-related iron accumulation and demyelination in the basal ganglia are closely related to verbal memory and executive functioning. Sci Rep 2021; 11:9438. [PMID: 33941809 PMCID: PMC8093241 DOI: 10.1038/s41598-021-88840-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 04/13/2021] [Indexed: 02/02/2023] Open
Abstract
Age-related cognitive decline has been linked to alterations of the dopaminergic system and its subcortical trajectories. Recent work suggests a critical role of iron accumulation within the basal ganglia (BG) in verbal memory performance, and increased iron levels have been related to demyelination. However, the specificity of age-related iron increases with respect to cognitive functions remains unclear. Therefore, we investigated the interplay of age, cognitive performance, and structural integrity of the BG. In total, 79 healthy older participants underwent a broad cognitive assessment (fluid and crystallized intelligence, verbal and numeric memory, processing speed, executive functions) and structural MRI. As expected, performance in most cognitive tests had a negative relationship with age. Moreover, BG grey matter volume and magnetization transfer (MT, indicative of myelin) decreased, and R2* (indicative of iron) increased with age. Importantly, R2* and demyelination negatively correlated with verbal memory and executive functions. Within the SN/VTA, age correlated negatively with MT, but there was no clear evidence in favor of a relationship between behavior and R2* or MT. Our results suggest that age-related increases in iron and demyelination within the BG, which are part of a fronto-striatal network, not only impact on verbal memory but also executive functions.
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Affiliation(s)
- Davina Biel
- grid.4562.50000 0001 0057 2672Department of Psychology, University of Lübeck, 23562 Lübeck, Germany ,grid.5252.00000 0004 1936 973XInstitute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, 81377 Munich, Germany
| | - Tineke K. Steiger
- grid.4562.50000 0001 0057 2672Department of Psychology, University of Lübeck, 23562 Lübeck, Germany
| | - Nico Bunzeck
- grid.4562.50000 0001 0057 2672Department of Psychology, University of Lübeck, 23562 Lübeck, Germany ,grid.4562.50000 0001 0057 2672Center of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany
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Crescenzo F, Marastoni D, Pisani AI, Tamanti A, Dapor C, Colombi A, Brillo A, Magliozzi R, Pizzini FB, Castellaro M, Calabrese M. The Prognostic Value of White-Matter Selective Double Inversion Recovery MRI Sequence in Multiple Sclerosis: An Exploratory Study. Diagnostics (Basel) 2021; 11:diagnostics11040686. [PMID: 33921278 PMCID: PMC8069390 DOI: 10.3390/diagnostics11040686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Revised: 04/08/2021] [Accepted: 04/09/2021] [Indexed: 11/30/2022] Open
Abstract
Using a white-matter selective double inversion recovery sequence (WM-DIR) that suppresses both grey matter (GM) and cerebrospinal fluid (CSF) signals, some white matter (WM) lesions appear surrounded by a dark rim. These dark rim lesions (DRLs) seem to be specific for multiple sclerosis (MS). They could be of great usefulness in clinical practice, proving to increase the MRI diagnostic criteria specificity. The aims of this study are the identification of DRLs on 1.5 T MRI, the exploration of the relationship between DRLs and disease course, the characterization of DRLs with respect to perilesional normal-appearing WM using magnetization transfer imaging, and the investigation of possible differences in the underlying tissue properties by assessing WM-DIR images obtained at 3.0 T MRI. DRLs are frequent in primary progressive MS (PPMS) patients. Amongst relapsing-remitting MS (RRMS) patients, DRLs are associated with a high risk of the disease worsening and secondary progressive MS (SPMS) conversion after 15 years. The mean magnetization transfer ratio (MTR) of DRLs is significantly different from the lesion without the dark rim, suggesting that DRLs correspond to more destructive lesions.
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Affiliation(s)
- Francesco Crescenzo
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy; (F.C.); (D.M.); (A.I.P.); (A.T.); (C.D.); (A.C.); (A.B.); (R.M.); (M.C.)
- Neurology Unit, Mater Salutis Hospital, Legnago, 37045 Verona, Italy
| | - Damiano Marastoni
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy; (F.C.); (D.M.); (A.I.P.); (A.T.); (C.D.); (A.C.); (A.B.); (R.M.); (M.C.)
| | - Anna Isabella Pisani
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy; (F.C.); (D.M.); (A.I.P.); (A.T.); (C.D.); (A.C.); (A.B.); (R.M.); (M.C.)
| | - Agnese Tamanti
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy; (F.C.); (D.M.); (A.I.P.); (A.T.); (C.D.); (A.C.); (A.B.); (R.M.); (M.C.)
| | - Caterina Dapor
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy; (F.C.); (D.M.); (A.I.P.); (A.T.); (C.D.); (A.C.); (A.B.); (R.M.); (M.C.)
| | - Annalisa Colombi
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy; (F.C.); (D.M.); (A.I.P.); (A.T.); (C.D.); (A.C.); (A.B.); (R.M.); (M.C.)
| | - Alessandro Brillo
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy; (F.C.); (D.M.); (A.I.P.); (A.T.); (C.D.); (A.C.); (A.B.); (R.M.); (M.C.)
| | - Roberta Magliozzi
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy; (F.C.); (D.M.); (A.I.P.); (A.T.); (C.D.); (A.C.); (A.B.); (R.M.); (M.C.)
| | | | - Marco Castellaro
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy; (F.C.); (D.M.); (A.I.P.); (A.T.); (C.D.); (A.C.); (A.B.); (R.M.); (M.C.)
| | - Massimiliano Calabrese
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy; (F.C.); (D.M.); (A.I.P.); (A.T.); (C.D.); (A.C.); (A.B.); (R.M.); (M.C.)
- Correspondence:
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