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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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Mao A, Flassbeck S, Marchetto E, Masurkar AV, Rusinek H, Assländer J. Sensitivity of unconstrained quantitative magnetization transfer MRI to Amyloid burden in preclinical Alzheimer's disease. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.04.15.24305860. [PMID: 38699343 PMCID: PMC11065014 DOI: 10.1101/2024.04.15.24305860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2024]
Abstract
Introduction Magnetization transfer MRI is sensitive to semi-solid macromolecules, including amyloid beta, and has been used to discriminate Alzheimer's disease (AD) patients from controls. Here, we utilize an unconstrained 2-pool quantitative MT (qMT) approach that quantifies the longitudinal relaxation rates of free water and semi-solids separately, and investigate its sensitivity to amyloid accumulation in preclinical subjects. Methods We recruited 15 cognitively normal subjects, of which nine were amyloid positive by [ 18 F]Florbetaben PET. A 12 min qMT scan was used to estimate the unconstrained 2-pool qMT parameters. Group comparisons and correlations were analyzed at the lobar level. Results The exchange rate and semi-solid pool's were sensitive to the amyloid concentration. The former finding is consistent with previous reports in clinical AD, but the latter is novel as its value is typically constrained. Discussion qMT MRI may be a promising surrogate marker of amyloid beta without the need for contrast agents or radiotracers.
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Serra L, Gabrielli GB, Di Domenico C, Del Bono C, Marra C, Lopiano L, Caltagirone C, Bozzali M. Are the inhibitory and faciliatory effects during retrieval of semantically related items present in amnestic mild cognitive impairment? J Neuropsychol 2023; 17:63-80. [PMID: 35968861 DOI: 10.1111/jnp.12286] [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: 08/31/2021] [Revised: 07/18/2022] [Accepted: 07/20/2022] [Indexed: 11/28/2022]
Abstract
Prefrontal functions subserve inhibition control for retrieval of semantically related items inducing forgetting 19 a-MCI patients and 29 controls underwent neuropsychological evaluation and retrieval-practice paradigm (RPP) to estimate baseline remember (BR), retrieval-induced facilitation (FAC) and retrieval-induced forgetting (RIF). A-MCI patients underwent also 3 T-MRI to assess relationship between regional grey matter (rGM) volumes and RPP indexes Behaviourally, RIF and FAC were both observed controls, while RIF only was observed in a-MCI patients. In patients but not in controls, RIF was associated with cognitive efficiency and FAC with memory performance. Patients showed also associations between BR and rGM volumes in the precuneus, no association was found between rGM volumes and RIF and FAC. A-MCI patients did not benefit from repeated practice during retrieval of studied items, which is likely due to their memory disorder. In contrast, patient cognitive efficiency would drive retrieval suppression of interfering stimuli.
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Affiliation(s)
- Laura Serra
- Neuroimaging Laboratory, IRCCS Santa Lucia Foundation, Rome, Italy
| | | | | | - Chiara Del Bono
- Neuroimaging Laboratory, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Camillo Marra
- Institute of Neurology, Catholic University, Rome, Italy
| | - Leonardo Lopiano
- Department of Neuroscience 'Rita Levi Montalcini', University of Torino, Turin, Italy
| | - Carlo Caltagirone
- Laboratory of Clinical and Behavioural Neurology, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Marco Bozzali
- Department of Neuroscience 'Rita Levi Montalcini', University of Torino, Turin, Italy.,Department of Neuroscience, Brighton & Sussex Medical School, University of Sussex, Brighton, UK
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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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6
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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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7
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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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8
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Huang J, Lai JHC, Tse KH, Cheng GWY, Liu Y, Chen Z, Han X, Chen L, Xu J, Chan KWY. Deep neural network based CEST and AREX processing: Application in imaging a model of Alzheimer's disease at 3 T. Magn Reson Med 2021; 87:1529-1545. [PMID: 34657318 DOI: 10.1002/mrm.29044] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 08/26/2021] [Accepted: 09/22/2021] [Indexed: 02/06/2023]
Abstract
PURPOSE To optimize and apply deep neural network based CEST (deepCEST) and apparent exchange dependent-relaxation (deepAREX) for imaging the mouse brain with Alzheimer's disease (AD) at 3T MRI. METHODS CEST and T1 data of central and anterior brain slices of 10 AD mice and 10 age-matched wild type (WT) mice were acquired at a 3T animal MRI scanner. The networks of deepCEST/deepAREX were optimized and trained on the WT data. The CEST/AREX contrasts of AD and WT mice predicted by the networks were analyzed and further validated by immunohistochemistry. RESULTS After optimization and training on CEST data of WT mice, deepCEST/deepAREX could rapidly (~1 s) generate precise CEST and AREX results for unseen CEST data of AD mice, indicating the accuracy and generalization of the networks. Significant lower amide weighted (3.5 ppm) signal related to amyloid β-peptide (Aβ) plaque depositions, which was validated by immunohistochemistry results, was detected in both central and anterior brain slices of AD mice compared to WT mice. Decreased magnetization transfer (MT) signal was also found in AD mice especially in the anterior slice. CONCLUSION DeepCEST/deepAREX could rapidly generate accurate CEST/AREX contrasts in animal study. The well-optimized deepCEST/deepAREX have potential for AD differentiation at 3T MRI.
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Affiliation(s)
- Jianpan Huang
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, China
| | - Joseph H C Lai
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, China
| | - Kai-Hei Tse
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong, China
| | - Gerald W Y Cheng
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong, China
| | - Yang Liu
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, China.,Hong Kong Centre for Cerebro-Cardiovascular Health Engineering (COCHE), Hong Kong, China
| | - Zilin Chen
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, China
| | - Xiongqi Han
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, China
| | - Lin Chen
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, Maryland, USA.,Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, Xiamen University, Xiamen, China
| | - Jiadi Xu
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, Maryland, USA.,Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Kannie W Y Chan
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, China.,Hong Kong Centre for Cerebro-Cardiovascular Health Engineering (COCHE), Hong Kong, China.,Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,City University of Hong Kong Shenzhen Research Institute, Shenzhen, China
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9
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Leddy S, Serra L, Esposito D, Vizzotto C, Giulietti G, Silvestri G, Petrucci A, Meola G, Lopiano L, Cercignani M, Bozzali M. Lesion distribution and substrate of white matter damage in myotonic dystrophy type 1: Comparison with multiple sclerosis. NEUROIMAGE-CLINICAL 2021; 29:102562. [PMID: 33516936 PMCID: PMC7848627 DOI: 10.1016/j.nicl.2021.102562] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 01/06/2021] [Accepted: 01/08/2021] [Indexed: 02/08/2023]
Abstract
The supratentorial distribution of lesions is similar in DM1 and MS. Patients with DM1 do not show infratentorial lesions. Quantitative magnetization transfer supports the presence of demyelination in DM1 lesions, but not in the NAWM. Anterior temporal lobe lesions in DM1 might have a different substrate than periventricular ones.
Myotonic Dystrophy type 1 (DM1) is an autosomal dominant condition caused by expansion of the CTG triplet repeats within the myotonic dystrophy protein of the kinase (DMPK) gene. The central nervous system is involved in the disease, with multiple symptoms including cognitive impairment. A typical feature of DM1 is the presence of widespread white matter (WM) lesions, whose total volume is associated with CTG triplet expansion. The aim of this study was to characterize the distribution and pathological substrate of these lesions as well as the normal appearing WM (NAWM) using quantitative magnetization transfer (qMT) MRI, and comparing data from DM1 patients with those from patients with multiple sclerosis (MS). Twenty-eight patients with DM1, 29 patients with relapsing-remitting MS, and 15 healthy controls had an MRI scan, including conventional and qMT imaging. The average pool size ratio (F), a proxy of myelination, was computed within lesions and NAWM for every participant. The lesion masks were warped into MNI space and lesion probability maps were obtained for each patient group. The lesion distribution, total lesion load and the tissue-specific mean F were compared between groups. The supratentorial distribution of lesions was similar in the 2 patient groups, although mean lesion volume was higher in MS than DM1. DM1 presented higher prevalence of anterior temporal lobe lesions, but none in the cerebellum and brainstem. Significantly reduced F values were found within DM1 lesions, suggesting a loss of myelin density. While F was reduced in the NAWM of MS patients, it did not differ between DM1 and controls. Our results provide further evidence for a need to compare histology and imaging using new MRI techniques in DM1 patients, in order to further our understanding of the underlying disease process contributing to WM disease.
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Affiliation(s)
- Sara Leddy
- Clinical Imaging Sciences Centre, Brighton and Sussex Medical School, Brighton, United Kingdom; Brighton and Sussex University Hospital Trust, Brighton, United Kingdom
| | - Laura Serra
- Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy
| | - Davide Esposito
- Clinical Imaging Sciences Centre, Brighton and Sussex Medical School, Brighton, United Kingdom
| | - Camilla Vizzotto
- Clinical Imaging Sciences Centre, Brighton and Sussex Medical School, Brighton, United Kingdom
| | | | - Gabriella Silvestri
- Department of Neuroscience, Fondazione Policlinico Gemelli IRCCS, Università Cattolica del S. Cuore, Rome, Italy
| | - Antonio Petrucci
- UOC Neurologia e Neurofisiopatologia, AO San Camillo Forlanini, Rome, Italy
| | - Giovanni Meola
- Department of Neurorehabilitation Sciences, Casa di Cura Policlinico, Milan, Italy; Department of Biomedical Science for Health, University of Milan, Milan, Italy
| | - Leonardo Lopiano
- 'Rita Levi Montalcini' Department of Neuroscience, University of Torino, Turin, Italy
| | - Mara Cercignani
- Clinical Imaging Sciences Centre, Brighton and Sussex Medical School, Brighton, United Kingdom; Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy
| | - Marco Bozzali
- Clinical Imaging Sciences Centre, Brighton and Sussex Medical School, Brighton, United Kingdom; UOC Neurologia e Neurofisiopatologia, AO San Camillo Forlanini, Rome, Italy.
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10
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Mole JP, Fasano F, Evans J, Sims R, Kidd E, Aggleton JP, Metzler-Baddeley C. APOE-ε4-related differences in left thalamic microstructure in cognitively healthy adults. Sci Rep 2020; 10:19787. [PMID: 33188215 PMCID: PMC7666117 DOI: 10.1038/s41598-020-75992-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 10/15/2020] [Indexed: 01/05/2023] Open
Abstract
APOE-ε4 is a main genetic risk factor for developing late onset Alzheimer's disease (LOAD) and is thought to interact adversely with other risk factors on the brain. However, evidence regarding the impact of APOE-ε4 on grey matter structure in asymptomatic individuals remains mixed. Much attention has been devoted to characterising APOE-ε4-related changes in the hippocampus, but LOAD pathology is known to spread through the whole of the Papez circuit including the limbic thalamus. Here, we tested the impact of APOE-ε4 and two other risk factors, a family history of dementia and obesity, on grey matter macro- and microstructure across the whole brain in 165 asymptomatic individuals (38-71 years). Microstructural properties of apparent neurite density and dispersion, free water, myelin and cell metabolism were assessed with Neurite Orientation Density and Dispersion (NODDI) and quantitative magnetization transfer (qMT) imaging. APOE-ε4 carriers relative to non-carriers had a lower macromolecular proton fraction (MPF) in the left thalamus. No risk effects were present for cortical thickness, subcortical volume, or NODDI indices. Reduced thalamic MPF may reflect inflammation-related tissue swelling and/or myelin loss in APOE-ε4. Future prospective studies should investigate the sensitivity and specificity of qMT-based MPF as a non-invasive biomarker for LOAD risk.
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Affiliation(s)
- Jilu P Mole
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cathays, Cardiff, CF24 4HQ, UK
| | - Fabrizio Fasano
- Siemens Healthcare, Henkestrasse 127, 91052, Erlangen, Germany
| | - John Evans
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cathays, Cardiff, CF24 4HQ, UK
| | - Rebecca Sims
- Division of Psychological Medicine and Clinical Neuroscience, School of Medicine, Cardiff University, Haydn Ellis Building, Maindy Road, Cathays, Cardiff, CF24 4HQ, UK
| | - Emma Kidd
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Redwood Building, King Edward VII Avenue,, Cardiff, CF10 3NB, UK
| | - John P Aggleton
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cathays, Cardiff, CF24 4HQ, UK
| | - Claudia Metzler-Baddeley
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cathays, Cardiff, CF24 4HQ, UK.
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11
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Mole JP, Fasano F, Evans J, Sims R, Hamilton DA, Kidd E, Metzler-Baddeley C. Genetic risk of dementia modifies obesity effects on white matter myelin in cognitively healthy adults. Neurobiol Aging 2020; 94:298-310. [PMID: 32736120 DOI: 10.1016/j.neurobiolaging.2020.06.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 06/19/2020] [Accepted: 06/20/2020] [Indexed: 01/05/2023]
Abstract
APOE-ε4 is a major genetic risk factor for late-onset Alzheimer's disease that interacts with other risk factors, but the nature of such combined effects remains poorly understood. We quantified the impact of APOE-ε4, family history (FH) of dementia, and obesity on white matter (WM) microstructure in 165 asymptomatic adults (38-71 years old) using quantitative magnetization transfer and neurite orientation dispersion and density imaging. Microstructural properties of the fornix, parahippocampal cingulum, and uncinate fasciculus were compared with those in motor and whole-brain WM regions. Widespread interaction effects between APOE, FH, and waist-hip ratio were found in the myelin-sensitive macromolecular proton fraction from quantitative magnetization transfer. Among individuals with the highest genetic risk (FH+ and APOE-ε4), obesity was associated with reduced macromolecular proton fraction in the right parahippocampal cingulum, whereas no effects were present for those without FH. Risk effects on apparent myelin were moderated by hypertension and inflammation-related markers. These findings suggest that genetic risk modifies the impact of obesity on WM myelin consistent with neuroglia models of aging and late-onset Alzheimer's disease.
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Affiliation(s)
- Jilu P Mole
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, UK
| | | | - John Evans
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, UK
| | - Rebecca Sims
- Division of Psychological Medicine and Clinical Neuroscience, School of Medicine, Cardiff University, Cardiff, UK
| | - Derek A Hamilton
- Department of Psychology, The University of New Mexico, Albuquerque, NM, USA
| | - Emma Kidd
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, UK
| | - Claudia Metzler-Baddeley
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, UK.
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12
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Coad BM, Craig E, Louch R, Aggleton JP, Vann SD, Metzler-Baddeley C. Precommissural and postcommissural fornix microstructure in healthy aging and cognition. Brain Neurosci Adv 2020; 4:2398212819899316. [PMID: 32219177 PMCID: PMC7085915 DOI: 10.1177/2398212819899316] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 12/11/2019] [Indexed: 11/23/2022] Open
Abstract
The fornix is a key tract of the hippocampal formation, whose status is presumed to contribute to age-related cognitive decline. The precommissural and postcommissural fornix subdivisions form respective basal forebrain/frontal and diencephalic networks that may differentially affect aging and cognition. We employed multi-parametric magnetic resonance imaging (MRI) including neurite orientation density and dispersion imaging, quantitative magnetization transfer (qMT), and T1-relaxometry MRI to investigate the microstructural properties of these fornix subdivisions and their relationship with aging and cognition in 149 asymptomatic participants (38-71 years). Aging was associated with increased free water signal and reductions in myelin-sensitive R1 and qMT indices but no apparent axon density differences in both precommissural and postcommissural fibers. Precommissural relative to postcommissural fibers showed a distinct microstructural pattern characterised by larger free water signal and axon orientation dispersion, with lower apparent myelin and axon density. Furthermore, differences in postcommissural microstructure were related to performance differences in object-location paired-associate learning. These results provide novel in vivo neuroimaging evidence for distinct microstructural properties of precommissural and postcommissural fibers that are consistent with their anatomy as found in axonal tracer studies, as well as for a contribution of postcommissural fibers to the learning of spatial configurations.
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Affiliation(s)
- Bethany M. Coad
- Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff, UK
- School of Psychology, Cardiff University, Cardiff, UK
| | - Emma Craig
- School of Psychology, Cardiff University, Cardiff, UK
| | - Rebecca Louch
- School of Psychology, Cardiff University, Cardiff, UK
| | | | | | - Claudia Metzler-Baddeley
- Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff, UK
- School of Psychology, Cardiff University, Cardiff, UK
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13
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Sporn L, MacMillan EL, Ge R, Greenway K, Vila-Rodriguez F, Laule C. Longer Repetition Time Proton MR Spectroscopy Shows Increasing Hippocampal and Parahippocampal Metabolite Concentrations with Aging. J Neuroimaging 2019; 29:592-597. [PMID: 31273871 DOI: 10.1111/jon.12648] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 06/11/2019] [Accepted: 06/14/2019] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND AND PURPOSE Previous magnetic resonance spectroscopy (MRS) studies have concluded that hippocampal and parahippocampal metabolite concentrations remain stable during healthy adult aging. However, these studies used short repetition times (TR ≤ 2 seconds), which lead to incomplete longitudinal magnetization recovery, and thus, heavily T1 -weighted measurements. It is important to accurately characterize brain metabolites changes with age to enable appropriate interpretations of MRS findings in the context of neurodegenerative diseases. Our goal was to assess hippocampal brain metabolite concentrations in a large cohort of diversely aged healthy volunteers using a longer TR of 4 seconds. METHODS Left hippocampal MR spectra were collected from 38 healthy volunteers at 3T. Absolute metabolite concentrations were determined for total N-acetyl-aspartate (tNAA), total creatine (tCr), total choline (tCho), glutamate and glutamine (Glx), and myoinositol (mI). Individual partial correlations between each metabolite with age were assessed using demographic information and voxel compartmentation as confounders. RESULTS Hippocampal tNAA, tCr, tCho, and mI all increased with age (NAA: R2 = .17, P = .041; tCr: R2 = .45, P = .0002; tCho: R2 = .37, P = .001; mI: R2 = .44, P = .0003). There were no relationships between age and signal to noise ratio, linewidth, or scan date, indicating the correlations were not confounded by spectral quality. Furthermore, we did not observe a trend with age in the voxel tissue compartmentations. CONCLUSIONS We observed increases in hippocampal/parahippocampal metabolite concentrations with age, a finding that is in contrast to previous literature. Our findings illustrate the importance of using a sufficiently long TR in MRS to avoid T1 -relaxation effects influencing the measurement of absolute metabolite concentrations.
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Affiliation(s)
- Leo Sporn
- Department of Physics & Astronomy, University of British Columbia, Vancouver, British Columbia, Canada.,International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
| | - Erin L MacMillan
- School of Mechatronic Systems Engineering, Faculty of Applied Sciences, Simon Fraser University, Vancouver, British Columbia, Canada.,Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada.,Philips, Markham, Ontario, Canada
| | - Ruiyang Ge
- Department of Psychiatry, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kyle Greenway
- Department of Psychiatry, McGill University, Montreal, Quebec, Canada
| | - Fidel Vila-Rodriguez
- Department of Psychiatry, University of British Columbia, Vancouver, British Columbia, Canada
| | - Cornelia Laule
- Department of Physics & Astronomy, University of British Columbia, Vancouver, British Columbia, Canada.,International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada.,Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada.,Pathology & Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada
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14
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Makovac E, Serra L, Di Domenico C, Marra C, Caltagirone C, Cercignani M, Bozzali M. Quantitative Magnetization Transfer of White Matter Tracts Correlates with Diffusion Tensor Imaging Indices in Predicting the Conversion from Mild Cognitive Impairment to Alzheimer's Disease. J Alzheimers Dis 2019; 63:561-575. [PMID: 29689722 DOI: 10.3233/jad-170995] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Patients with amnestic mild cognitive impairment (aMCI) have higher probability to develop Alzheimer's disease (AD) than elderly controls. The detection of subtle changes in brain structure associated with disease progression and the development of tools to identify patients at high risk for dementia in a short time is crucial. Here, we used probabilistic white matter (WM) tractography to explore microstructural alterations within the main association, limbic, and commissural pathways in aMCI patients who converted to AD after 1 year follow-up (MCIconverters) and those who remained stable (MCIstable). Both diffusion tensor imaging (DTI) and quantitative magnetization transfer (qMT) parameters have been considered for a comprehensive pathophysiological characterization of the WM damage. Overall, tract-specific parameters derived from qMT and DTI at baseline were able to differentiate aMCI patients who converted to AD from those who remained stable in time. In particular, the qMT exchange rate, RMB0, of the right uncinate fasciculus was significantly decreased in MCIconverters, whereas fractional anisotropy was significantly decreased in the bilateral superior cingulum in MCIconverters compared to MCIstable. These results confirm the involvement of WM and particularly of association fibers in the progression of AD, highlighting disconnection as a potential mechanism.
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Affiliation(s)
- Elena Makovac
- Neuroimaging Laboratory, IRCCS Santa Lucia Foundation, Rome
| | - Laura Serra
- Neuroimaging Laboratory, IRCCS Santa Lucia Foundation, Rome
| | | | | | - Carlo Caltagirone
- Department of Clinical and Behavioural Neurology, IRCCS Santa Lucia Foundation, Rome.,Department of Systems Medicine, University of Rome 'Tor Vergata', Rome
| | - Mara Cercignani
- Neuroimaging Laboratory, IRCCS Santa Lucia Foundation, Rome.,Department of Neuroscience, Brighton and Sussex Medical School, University of Sussex, Brighton, UK
| | - Marco Bozzali
- Neuroimaging Laboratory, IRCCS Santa Lucia Foundation, Rome.,Department of Neuroscience, Brighton and Sussex Medical School, University of Sussex, Brighton, UK
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15
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Kim J, Lee S, Choi SH, Park S. Rapid framework for quantitative magnetization transfer imaging with interslice magnetization transfer and dictionary‐driven fitting approaches. Magn Reson Med 2019; 82:1671-1683. [DOI: 10.1002/mrm.27850] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 05/16/2019] [Accepted: 05/20/2019] [Indexed: 01/02/2023]
Affiliation(s)
- Jae‐Woong Kim
- Magnetic Resonance Imaging Laboratory, Department of Bio and Brain Engineering Korea Advanced Institute of Science and Technology Daejeon Korea
| | - Sul‐Li Lee
- Magnetic Resonance Imaging Laboratory, Department of Bio and Brain Engineering Korea Advanced Institute of Science and Technology Daejeon Korea
| | - Seung Hong Choi
- Department of Radiology Seoul National University College of Medicine Seoul Korea
| | - Sung‐Hong Park
- Magnetic Resonance Imaging Laboratory, Department of Bio and Brain Engineering Korea Advanced Institute of Science and Technology Daejeon Korea
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16
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Metzler-Baddeley C, Mole JP, Leonaviciute E, Sims R, Kidd EJ, Ertefai B, Kelso-Mitchell A, Gidney F, Fasano F, Evans J, Jones DK, Baddeley RJ. Sex-specific effects of central adiposity and inflammatory markers on limbic microstructure. Neuroimage 2019; 189:793-803. [PMID: 30735826 PMCID: PMC6435101 DOI: 10.1016/j.neuroimage.2019.02.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 02/01/2019] [Accepted: 02/04/2019] [Indexed: 01/09/2023] Open
Abstract
Midlife obesity is a risk factor of late onset Alzheimer's disease (LOAD) but why this is the case remains unknown. As systemic inflammation is involved in both conditions, obesity-related neuroinflammation may contribute to damage in limbic structures important in LOAD. Here, we investigated the hypothesis that systemic inflammation would mediate central obesity related effects on limbic tissue microstructure in 166 asymptomatic individuals (38-71 years old). We employed MRI indices sensitive to myelin and neuroinflammation [macromolecular proton fraction (MPF) and kf] from quantitative magnetization transfer (qMT) together with indices from neurite orientation dispersion and density imaging (NODDI) to investigate the effects of central adiposity on the fornix, parahippocampal cingulum, uncinate fasciculus (compared with whole brain white matter and corticospinal tract) and the hippocampus. Central obesity was assessed with the Waist Hip Ratio (WHR) and abdominal visceral and subcutaneous fat area fractions (VFF, SFF), and systemic inflammation with blood plasma concentrations of leptin, adiponectin, C-reactive protein and interleukin 8. Men were significantly more centrally obese and had higher VFF than women. Individual differences in WHR and in VFF were negatively correlated with differences in fornix MPF and kf, but not with any differences in neurite microstructure. In women, age mediated the effects of VFF on fornix MPF and kf, whilst in men differences in the leptin and adiponectin ratio fully mediated the effect of WHR on fornix MPF. These results suggest that visceral fat related systemic inflammation may damage myelin-related properties of the fornix, a key limbic structure known to be involved in LOAD.
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Affiliation(s)
- Claudia Metzler-Baddeley
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cathays, Cardiff, CF24 4HQ, UK.
| | - Jilu P Mole
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cathays, Cardiff, CF24 4HQ, UK
| | - Erika Leonaviciute
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cathays, Cardiff, CF24 4HQ, UK
| | - Rebecca Sims
- Psychological Medicine and Clinical Neurosciences, School of Medicine, Cardiff University, Maindy Road, Cathays, Cardiff, CF24 4HQ, UK
| | - Emma J Kidd
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Redwood Building, King Edward VII Avenue, Cardiff, CF10 3NB, UK
| | - Benyamin Ertefai
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Redwood Building, King Edward VII Avenue, Cardiff, CF10 3NB, UK
| | - Aurora Kelso-Mitchell
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cathays, Cardiff, CF24 4HQ, UK
| | - Florence Gidney
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cathays, Cardiff, CF24 4HQ, UK
| | - Fabrizio Fasano
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cathays, Cardiff, CF24 4HQ, UK; Siemens Healthcare, Head Office, Sir William Siemens Square, Surrey, GU16 8QD, UK
| | - John Evans
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cathays, Cardiff, CF24 4HQ, UK
| | - Derek K Jones
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cathays, Cardiff, CF24 4HQ, UK; School of Psychology, Faculty of Health Sciences, Australian Catholic University, Melbourne, Victoria 3065, Australia
| | - Roland J Baddeley
- Experimental Psychology, University of Bristol, 12a Priory Road, BS8 1TU, UK
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17
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Metzler-Baddeley C, Mole JP, Sims R, Fasano F, Evans J, Jones DK, Aggleton JP, Baddeley RJ. Fornix white matter glia damage causes hippocampal gray matter damage during age-dependent limbic decline. Sci Rep 2019; 9:1060. [PMID: 30705365 PMCID: PMC6355929 DOI: 10.1038/s41598-018-37658-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Accepted: 12/11/2018] [Indexed: 12/21/2022] Open
Abstract
Aging leads to gray and white matter decline but their causation remains unclear. We explored two classes of models of age and dementia risk related brain changes. The first class of models emphasises the importance of gray matter: age and risk-related processes cause neurodegeneration and this causes damage in associated white matter tracts. The second class of models reverses the direction of causation: aging and risk factors cause white matter damage and this leads to gray matter damage. We compared these models with linear mediation analysis and quantitative MRI indices (from diffusion, quantitative magnetization transfer and relaxometry imaging) of tissue properties in two limbic structures implicated in age-related memory decline: the hippocampus and the fornix in 166 asymptomatic individuals (aged 38–71 years). Aging was associated with apparent glia but not neurite density damage in the fornix and the hippocampus. Mediation analysis supported white matter damage causing gray matter decline; controlling for fornix glia damage, the correlations between age and hippocampal damage disappear, but not vice versa. Fornix and hippocampal differences were both associated with reductions in episodic memory performance. These results suggest that fornix white matter glia damage may cause hippocampal gray matter damage during age-dependent limbic decline.
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Affiliation(s)
- Claudia Metzler-Baddeley
- Cardiff University Brain Research Imaging Centre (CUBRIC), Maindy Road, Cathays, Cardiff, CF24 4HQ, UK.
| | - Jilu P Mole
- Cardiff University Brain Research Imaging Centre (CUBRIC), Maindy Road, Cathays, Cardiff, CF24 4HQ, UK
| | - Rebecca Sims
- Psychological Medicine and Clinical Neurosciences, School of Medicine, Cardiff University, Maindy Road, Cathays, Cardiff, CF24 4HQ, UK
| | - Fabrizio Fasano
- Cardiff University Brain Research Imaging Centre (CUBRIC), Maindy Road, Cathays, Cardiff, CF24 4HQ, UK.,Siemens Healthcare, Head Office, Sir William Siemens Square, Surrey, GU16 8QD, UK
| | - John Evans
- Cardiff University Brain Research Imaging Centre (CUBRIC), Maindy Road, Cathays, Cardiff, CF24 4HQ, UK
| | - Derek K Jones
- Cardiff University Brain Research Imaging Centre (CUBRIC), Maindy Road, Cathays, Cardiff, CF24 4HQ, UK.,School of Psychology, Faculty of Health Sciences, Australian Catholic University, Melbourne, Victoria, 3065, Australia
| | - John P Aggleton
- School of Psychology, Cardiff University, Tower Building, 70 Park Place, Cardiff, CF10 3AT, UK
| | - Roland J Baddeley
- Experimental Psychology, University of Bristol, 12a Priory Road, Bristol, BS8 1TU, UK
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18
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Whittaker HT, Zhu S, Di Curzio DL, Buist R, Li XM, Noy S, Wiseman FK, Thiessen JD, Martin M. T 1, diffusion tensor, and quantitative magnetization transfer imaging of the hippocampus in an Alzheimer's disease mouse model. Magn Reson Imaging 2018; 50:26-37. [PMID: 29545212 DOI: 10.1016/j.mri.2018.03.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 03/10/2018] [Indexed: 01/08/2023]
Abstract
Alzheimer's disease (AD) pathology causes microstructural changes in the brain. These changes, if quantified with magnetic resonance imaging (MRI), could be studied for use as an early biomarker for AD. The aim of our study was to determine if T1 relaxation, diffusion tensor imaging (DTI), and quantitative magnetization transfer imaging (qMTI) metrics could reveal changes within the hippocampus and surrounding white matter structures in ex vivo transgenic mouse brains overexpressing human amyloid precursor protein with the Swedish mutation. Delineation of hippocampal cell layers using DTI color maps allows more detailed analysis of T1-weighted imaging, DTI, and qMTI metrics, compared with segmentation of gross anatomy based on relaxation images, and with analysis of DTI or qMTI metrics alone. These alterations are observed in the absence of robust intracellular Aβ accumulation or plaque deposition as revealed by histology. This work demonstrates that multiparametric quantitative MRI methods are useful for characterizing changes within the hippocampal substructures and surrounding white matter tracts of mouse models of AD.
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Affiliation(s)
- Heather T Whittaker
- Biopsychology, University of Winnipeg, Winnipeg, MB R3B 2N2, Canada; Neurodegenerative Disease, University College London Institute of Neurology, London WC1N 3BG, United Kingdom.
| | - Shenghua Zhu
- Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB R3E 0T6, Canada
| | | | - Richard Buist
- Radiology, University of Manitoba, Winnipeg, MB R3E 0T6, Canada
| | - Xin-Min Li
- Psychiatry, University of Alberta, Alberta T6G 2R3, Canada
| | - Suzanna Noy
- Neurodegenerative Disease, University College London Institute of Neurology, London WC1N 3BG, United Kingdom
| | - Frances K Wiseman
- Neurodegenerative Disease, University College London Institute of Neurology, London WC1N 3BG, United Kingdom
| | - Jonathan D Thiessen
- Imaging Program, Lawson Health Research Institute, London, ON N6A 4V2, Canada; Medical Biophysics, Western University, London, Ontario, Canada
| | - Melanie Martin
- Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB R3E 0T6, Canada; Radiology, University of Manitoba, Winnipeg, MB R3E 0T6, Canada; Physics, University of Winnipeg, R3B 2N2, Canada
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19
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Dowell NG, Bouyagoub S, Tibble J, Voon V, Cercignani M, Harrison NA. Interferon-alpha-Induced Changes in NODDI Predispose to the Development of Fatigue. Neuroscience 2017; 403:111-117. [PMID: 29292074 PMCID: PMC6458994 DOI: 10.1016/j.neuroscience.2017.12.040] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 12/20/2017] [Accepted: 12/21/2017] [Indexed: 12/14/2022]
Abstract
NODDI, was used to probe subtle changes to tissue microstructure associated with IFN-α. We found a strong correlation between changes in neurite density index with acute and long-term fatigue following IFN-α. This observation confirms that the striatum is a key brain area targeted by IFN with implications for impaired motivation.
Interferon-alpha (IFN-α) is an important mediator of antiviral immune responses. It is also used clinically in the treatment of hepatitis-C infection. Though effective, IFN-α-based therapies can often impair mood, motivation and cognition, which when severe can appear indistinguishable from major depression. In susceptible patients, fatigue and motivational impairment emerge early and have been linked to changes in basal ganglia (striatal) metabolism, neurochemistry and microstructural integrity. Here we use neurite orientation dispersion and density imaging (NODDI) modeling of multi-shell diffusion MRI to investigate whether changes in orientation-dispersion index (ODI) or neurite density index (NDI) can predict the later emergence of IFN-α-induced fatigue. Eighteen patients initiating IFN-α-based treatment for hepatitis-C underwent diffusion MRI and blood sampling at baseline and 4 h after their first IFN-α injection. They were then followed up with regular psychological assessments for 12 weeks of treatment. IFN-α injection stimulated an acute inflammatory cytokine response and evoked acute fatigue that peaked between 4 and 12 weeks of treatment. Within the brain, IFN-α induced an acute increase in NDI in patients that experienced a simultaneous increase in IFN-α-induced fatigue but not in patients that did not. Acute changes in striatal microstructure additionally predicted the continued development of fatigue but not mood symptoms 4 and 8 weeks later into treatment. Our findings highlight the value of NODDI as a potential in vivo biomarker of the central effects of peripheral inflammation. We highlight the exquisite sensitivity of the striatum to IFN-α and further implicate striatal perturbation in IFN-α-induced fatigue.
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Affiliation(s)
- N G Dowell
- Department of Neuroscience, Brighton and Sussex Medical School, University of Sussex, Brighton BN1 9RR, UK.
| | - S Bouyagoub
- Department of Neuroscience, Brighton and Sussex Medical School, University of Sussex, Brighton BN1 9RR, UK
| | - J Tibble
- Department of Gastroenterology, Brighton & Sussex University Hospitals, Brighton, UK
| | - V Voon
- Department of Psychiatry, University of Cambridge, Cambridge CB2 0QQ, UK
| | - M Cercignani
- Department of Neuroscience, Brighton and Sussex Medical School, University of Sussex, Brighton BN1 9RR, UK; Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy
| | - N A Harrison
- Department of Neuroscience, Brighton and Sussex Medical School, University of Sussex, Brighton BN1 9RR, UK; Sackler Centre for Consciousness Science, University of Sussex, Falmer BN1 9RR, UK; Sussex Partnership NHS Foundation Trust, Brighton, UK
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20
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Melie-Garcia L, Slater D, Ruef A, Sanabria-Diaz G, Preisig M, Kherif F, Draganski B, Lutti A. Networks of myelin covariance. Hum Brain Mapp 2017; 39:1532-1554. [PMID: 29271053 PMCID: PMC5873432 DOI: 10.1002/hbm.23929] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 12/02/2017] [Accepted: 12/11/2017] [Indexed: 01/05/2023] Open
Abstract
Networks of anatomical covariance have been widely used to study connectivity patterns in both normal and pathological brains based on the concurrent changes of morphometric measures (i.e., cortical thickness) between brain structures across subjects (Evans, ). However, the existence of networks of microstructural changes within brain tissue has been largely unexplored so far. In this article, we studied in vivo the concurrent myelination processes among brain anatomical structures that gathered together emerge to form nonrandom networks. We name these "networks of myelin covariance" (Myelin-Nets). The Myelin-Nets were built from quantitative Magnetization Transfer data-an in-vivo magnetic resonance imaging (MRI) marker of myelin content. The synchronicity of the variations in myelin content between anatomical regions was measured by computing the Pearson's correlation coefficient. We were especially interested in elucidating the effect of age on the topological organization of the Myelin-Nets. We therefore selected two age groups: Young-Age (20-31 years old) and Old-Age (60-71 years old) and a pool of participants from 48 to 87 years old for a Myelin-Nets aging trajectory study. We found that the topological organization of the Myelin-Nets is strongly shaped by aging processes. The global myelin correlation strength, between homologous regions and locally in different brain lobes, showed a significant dependence on age. Interestingly, we also showed that the aging process modulates the resilience of the Myelin-Nets to damage of principal network structures. In summary, this work sheds light on the organizational principles driving myelination and myelin degeneration in brain gray matter and how such patterns are modulated by aging.
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Affiliation(s)
- Lester Melie-Garcia
- LREN, Department of Clinical Neurosciences, Lausanne University Hospital (CHUV), Switzerland
| | - David Slater
- LREN, Department of Clinical Neurosciences, Lausanne University Hospital (CHUV), Switzerland
| | - Anne Ruef
- LREN, Department of Clinical Neurosciences, Lausanne University Hospital (CHUV), Switzerland
| | - Gretel Sanabria-Diaz
- LREN, Department of Clinical Neurosciences, Lausanne University Hospital (CHUV), Switzerland
| | - Martin Preisig
- Department of Psychiatry, Lausanne University Hospital (CHUV), Switzerland
| | - Ferath Kherif
- LREN, Department of Clinical Neurosciences, Lausanne University Hospital (CHUV), Switzerland
| | - Bogdan Draganski
- LREN, Department of Clinical Neurosciences, Lausanne University Hospital (CHUV), Switzerland.,Max-Planck-Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Antoine Lutti
- LREN, Department of Clinical Neurosciences, Lausanne University Hospital (CHUV), Switzerland
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21
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Sled JG. Modelling and interpretation of magnetization transfer imaging in the brain. Neuroimage 2017; 182:128-135. [PMID: 29208570 DOI: 10.1016/j.neuroimage.2017.11.065] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 11/19/2017] [Accepted: 11/29/2017] [Indexed: 01/09/2023] Open
Abstract
Magnetization transfer contrast has yielded insight into brain tissue microstructure changes across the lifespan and in a range of disorders. This progress has been aided by the development of quantitative magnetization transfer imaging techniques able to extract intrinsic properties of the tissue that are independent of the specifics of the data acquisition. While the tissue properties extracted by these techniques do not map directly onto specific cellular structures or pathological processes, a growing body of work from animal models and histopathological correlations aids the in vivo interpretation of magnetization transfer properties of tissue. This review examines the biophysical models that have been developed to describe magnetization transfer contrast in tissue as well as the experimental evidence for the biological interpretation of magnetization transfer data in health and disease.
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Affiliation(s)
- John G Sled
- Hospital for Sick Children, Mouse Imaging Centre, Toronto, Ontario, Canada; Medical Biophysics, University of Toronto, Toronto, Ontario, Canada.
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22
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Cercignani M, Bouyagoub S. Brain microstructure by multi-modal MRI: Is the whole greater than the sum of its parts? Neuroimage 2017; 182:117-127. [PMID: 29097317 DOI: 10.1016/j.neuroimage.2017.10.052] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 09/12/2017] [Accepted: 10/25/2017] [Indexed: 12/11/2022] Open
Abstract
The MRI signal is dependent upon a number of sub-voxel properties of tissue, which makes it potentially able to detect changes occurring at a scale much smaller than the image resolution. This "microstructural imaging" has become one of the main branches of quantitative MRI. Despite the exciting promise of unique insight beyond the resolution of the acquired images, its widespread application is limited by the relatively modest ability of each microstructural imaging technique to distinguish between differing microscopic substrates. This is mainly due to the fact that MRI provides a very indirect measure of the tissue properties in which we are interested. A strategy to overcome this limitation lies in the combination of more than one technique, to exploit the relative contributions of differing physiological and pathological substrates to selected MRI contrasts. This forms the basis of multi-modal MRI, a broad concept that refers to many different ways of effectively combining information from more than one MRI contrast. This paper will review a range of methods that have been proposed to maximise the output of this combination, primarily falling into one of two approaches. The first one relies on data-driven methods, exploiting multivariate analysis tools able to capture overlapping and complementary information. The second approach, which we call "model-driven", aims at combining parameters extracted by existing biophysical or signal models to obtain new parameters, which are believed to be more accurate or more specific than the original ones. This paper will attempt to provide an overview of the advantages and limitations of these two philosophies.
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Affiliation(s)
- Mara Cercignani
- Clinical Imaging Sciences Centre, Department of Neuroscience, Brighton and Sussex Medical School, University of Sussex, Falmer, BN1 9RR, Brighton, East Sussex, UK; Neuroimaging Laboratory, Santa Lucia Foundation, Via Ardeatina 306, 00179, Rome, Italy.
| | - Samira Bouyagoub
- Clinical Imaging Sciences Centre, Department of Neuroscience, Brighton and Sussex Medical School, University of Sussex, Falmer, BN1 9RR, Brighton, East Sussex, UK
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23
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Pool size ratio of the substantia nigra in Parkinson's disease derived from two different quantitative magnetization transfer approaches. Neuroradiology 2017; 59:1251-1263. [PMID: 28986653 DOI: 10.1007/s00234-017-1911-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Accepted: 08/22/2017] [Indexed: 12/27/2022]
Abstract
PURPOSE We sought to measure quantitative magnetization transfer (qMT) properties of the substantia nigra pars compacta (SNc) in patients with Parkinson's disease (PD) and healthy controls (HCs) using a full qMT analysis and determine whether a rapid single-point measurement yields equivalent results for pool size ratio (PSR). METHODS Sixteen different MT-prepared MRI scans were obtained at 3 T from 16 PD patients and eight HCs, along with B1, B0, and relaxation time maps. Maps of PSR, free and macromolecular pool transverse relaxation times ([Formula: see text], [Formula: see text]) and rate of MT exchange between pools (k mf ) were generated using a full qMT model. PSR maps were also generated using a single-point qMT model requiring just two MT-prepared images. qMT parameter values of the SNc, red nucleus, cerebral crus, and gray matter were compared between groups and methods. RESULTS PSR of the SNc was the only qMT parameter to differ significantly between groups (p < 0.05). PSR measured via single-point analysis was less variable than with the full MT model, provided slightly better differentiation of PD patients from HCs (area under curve 0.77 vs. 0.75) with sensitivity of 0.75 and specificity of 0.87, and was better than transverse relaxation time in distinguishing PD patients from HCs (area under curve 0.71, sensitivity 0.87, and specificity 0.50). CONCLUSION The increased PSR observed in the SNc of PD patients may provide a novel biomarker of PD, possibly associated with an increased macromolecular content. Single-point PSR mapping with reduced variability and shorter scan times relative to the full qMT model appears clinically feasible.
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Battiston M, Grussu F, Ianus A, Schneider T, Prados F, Fairney J, Ourselin S, Alexander DC, Cercignani M, Gandini Wheeler-Kingshott CAM, Samson RS. An optimized framework for quantitative magnetization transfer imaging of the cervical spinal cord in vivo. Magn Reson Med 2017; 79:2576-2588. [PMID: 28921614 PMCID: PMC5836910 DOI: 10.1002/mrm.26909] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 08/15/2017] [Accepted: 08/16/2017] [Indexed: 11/06/2022]
Abstract
PURPOSE To develop a framework to fully characterize quantitative magnetization transfer indices in the human cervical cord in vivo within a clinically feasible time. METHODS A dedicated spinal cord imaging protocol for quantitative magnetization transfer was developed using a reduced field-of-view approach with echo planar imaging (EPI) readout. Sequence parameters were optimized based in the Cramer-Rao-lower bound. Quantitative model parameters (i.e., bound pool fraction, free and bound pool transverse relaxation times [ T2F, T2B], and forward exchange rate [kFB ]) were estimated implementing a numerical model capable of dealing with the novelties of the sequence adopted. The framework was tested on five healthy subjects. RESULTS Cramer-Rao-lower bound minimization produces optimal sampling schemes without requiring the establishment of a steady-state MT effect. The proposed framework allows quantitative voxel-wise estimation of model parameters at the resolution typically used for spinal cord imaging (i.e. 0.75 × 0.75 × 5 mm3 ), with a protocol duration of ∼35 min. Quantitative magnetization transfer parametric maps agree with literature values. Whole-cord mean values are: bound pool fraction = 0.11(±0.01), T2F = 46.5(±1.6) ms, T2B = 11.0(±0.2) µs, and kFB = 1.95(±0.06) Hz. Protocol optimization has a beneficial effect on reproducibility, especially for T2B and kFB . CONCLUSION The framework developed enables robust characterization of spinal cord microstructure in vivo using qMT. Magn Reson Med 79:2576-2588, 2018. © 2017 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
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Affiliation(s)
- Marco Battiston
- Queen Square MS Centre, UCL Institute of Neurology, University College London, London, United Kingdom
| | - Francesco Grussu
- Queen Square MS Centre, UCL Institute of Neurology, University College London, London, United Kingdom
| | - Andrada Ianus
- Centre for Medical Image Computing, Department of Computer Science, University College London, London, United Kingdom.,Champalimaud Neuroscience Programme, Champalimaud Centre for the Unknown, Lisbon, Portugal
| | | | - Ferran Prados
- Queen Square MS Centre, UCL Institute of Neurology, University College London, London, United Kingdom.,Translational Imaging Group, Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - James Fairney
- Queen Square MS Centre, UCL Institute of Neurology, University College London, London, United Kingdom.,UCL Department of Medical Physics and Bioengineering, University College London, London, United Kingdom
| | - Sebastien Ourselin
- Translational Imaging Group, Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Daniel C Alexander
- Centre for Medical Image Computing, Department of Computer Science, University College London, London, United Kingdom
| | - Mara Cercignani
- CISC, Department of Neuroscience, Brighton & Sussex Medical School, Brighton, Sussex, United Kingdom
| | - Claudia A M Gandini Wheeler-Kingshott
- Queen Square MS Centre, UCL Institute of Neurology, University College London, London, United Kingdom.,Department of Brain and Behavioural Sciences, University of Pavia, Pavia, Italy.,Brain MRI 3T Mondino Research Center, C. Mondino National Neurological Institute, Pavia, Italy
| | - Rebecca S Samson
- Queen Square MS Centre, UCL Institute of Neurology, University College London, London, United Kingdom
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25
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Mancini M, Giulietti G, Dowell N, Spanò B, Harrison N, Bozzali M, Cercignani M. Introducing axonal myelination in connectomics: A preliminary analysis of g-ratio distribution in healthy subjects. Neuroimage 2017; 182:351-359. [PMID: 28917698 DOI: 10.1016/j.neuroimage.2017.09.018] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 08/16/2017] [Accepted: 09/08/2017] [Indexed: 12/21/2022] Open
Abstract
Microstructural imaging and connectomics are two research areas that hold great potential for investigating brain structure and function. Combining these two approaches can lead to a better and more complete characterization of the brain as a network. The aim of this work is characterizing the connectome from a novel perspective using the myelination measure given by the g-ratio. The g-ratio is the ratio of the inner to the outer diameters of a myelinated axon, whose aggregated value can now be estimated in vivo using MRI. In two different datasets of healthy subjects, we reconstructed the structural connectome and then used the g-ratio estimated from diffusion and magnetization transfer data to characterize the network structure. Significant characteristics of g-ratio weighted graphs emerged. First, the g-ratio distribution across the edges of the graph did not show the power-law distribution observed using the number of streamlines as a weight. Second, connections involving regions related to motor and sensory functions were the highest in myelin content. We also observed significant differences in terms of the hub structure and the rich-club organization suggesting that connections involving hub regions present higher myelination than peripheral connections. Taken together, these findings offer a characterization of g-ratio distribution across the connectome in healthy subjects and lay the foundations for further investigating plasticity and pathology using a similar approach.
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Affiliation(s)
- Matteo Mancini
- Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy; Department of Neuroscience, Brighton and Sussex Medical School, University of Sussex, Brighton, UK.
| | | | - Nicholas Dowell
- Department of Neuroscience, Brighton and Sussex Medical School, University of Sussex, Brighton, UK
| | - Barbara Spanò
- Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy
| | - Neil Harrison
- Department of Neuroscience, Brighton and Sussex Medical School, University of Sussex, Brighton, UK
| | - Marco Bozzali
- Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy; Department of Neuroscience, Brighton and Sussex Medical School, University of Sussex, Brighton, UK
| | - Mara Cercignani
- Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy; Department of Neuroscience, Brighton and Sussex Medical School, University of Sussex, Brighton, UK
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Mancini M, Giulietti G, Spano B, Bozzali M, Cercignani M, Conforto S. Estimating multimodal brain connectivity in multiple sclerosis: an exploratory factor analysis. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2017; 2016:1131-1134. [PMID: 28268525 DOI: 10.1109/embc.2016.7590903] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Graph-theoretical approaches have become a popular way to model brain data collected using magnetic resonance imaging (MRI), both from the structural and the functional perspectives. In structural networks, tract-based mapping allows to model different aspects of brain structures by means of the specific characteristics of the different MRI modalities. However, there has been little effort to join the information carried by each modality and to understand what level of common variance is shown in these data. In this paper, we proposed a combined approach based on graph theory and factor analysis to model magnetization transfer and microstructural properties in 18 relapsing remitting multiple sclerosis (RRMS) patients and 17 healthy controls. After defining the common factors and outlining their relationships with MRI data, we evaluated between-group differences using global and local graph measures. The results showed that one common factor describes brain structures in terms of myelin and global integrity, and such factor is able to highlight specific between-group differences.
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28
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Praet J, Bigot C, Orije J, Naeyaert M, Shah D, Mai Z, Guns PJ, Van der Linden A, Verhoye M. Magnetization transfer contrast imaging detects early white matter changes in the APP/PS1 amyloidosis mouse model. NEUROIMAGE-CLINICAL 2016; 12:85-92. [PMID: 27408793 PMCID: PMC4925888 DOI: 10.1016/j.nicl.2016.06.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 05/19/2016] [Accepted: 06/15/2016] [Indexed: 01/02/2023]
Affiliation(s)
- Jelle Praet
- Bio-Imaging Lab, University of Antwerp, Antwerp, Belgium
| | | | - Jasmien Orije
- Bio-Imaging Lab, University of Antwerp, Antwerp, Belgium
| | | | - Disha Shah
- Bio-Imaging Lab, University of Antwerp, Antwerp, Belgium
| | - Zhenhua Mai
- Bio-Imaging Lab, University of Antwerp, Antwerp, Belgium
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Dowell NG, Cooper EA, Tibble J, Voon V, Critchley HD, Cercignani M, Harrison NA. Acute Changes in Striatal Microstructure Predict the Development of Interferon-Alpha Induced Fatigue. Biol Psychiatry 2016; 79:320-8. [PMID: 26169252 PMCID: PMC4725575 DOI: 10.1016/j.biopsych.2015.05.015] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Revised: 05/21/2015] [Accepted: 05/24/2015] [Indexed: 11/21/2022]
Abstract
BACKGROUND Interferon-alpha (IFN-α) is a key mediator of antiviral immune responses used clinically for hepatitis C treatment. Though effective, IFN-α induces marked behavioral changes that, when severe, can appear indistinguishable from major depression. Curiously, fatigue and motivational impairment evolve rapidly, suggesting acute engagement of immune-brain communicatory pathways, yet mood impairments typically emerge later, after weeks of treatment. Whether this reflects prolonged modulation of motivational processes underpinning fatigue or separate neurobiological mechanisms is currently unclear. METHODS Here, we used quantitative magnetization transfer (qMT) imaging, an advanced microstructural neuroimaging technique sensitive to effects of inflammation, in a prospective study design to measure acute brain changes to IFN-α and relate these to later development of discrete behavioral changes. Twenty-three patients initiating IFN-α treatment for hepatitis C underwent qMT imaging and blood sampling at baseline and 4 hours after their first IFN-α injection. Comprehensive behavioral and psychological assessments were completed at both scanning sessions and at treatment weeks 4, 8, 12, and 24. RESULTS IFN-α injection stimulated an acute inflammatory cytokine response and evoked fatigue that peaked between 4 and 12 weeks, preceding mood change by 4 weeks. In the brain, IFN-α induced an acute change in striatal microstructure that additionally predicted development of fatigue but not mood symptoms. CONCLUSIONS Our findings highlight qMT as an in vivo biomarker of central effects of peripheral inflammation. We demonstrate exquisite sensitivity of the striatum to IFN-α, implicate striatal perturbation in IFN-α-induced fatigue, and dissociate this from mechanisms underlying IFN-α-induced mood symptoms, providing empirical support for distinct neural substrates mediating actions on motivation and mood.
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Affiliation(s)
| | - Ella A. Cooper
- Brighton and Sussex Medical School, University of Sussex,Department of Gastroenterology, Brighton & Sussex University Hospitals, Brighton
| | - Jeremy Tibble
- Department of Gastroenterology, Brighton & Sussex University Hospitals, Brighton
| | - Valerie Voon
- Department of Psychiatry, University of Cambridge,Cambridge and Peterborough National Health Service Foundation Trust, Cambridge
| | - Hugo D. Critchley
- Brighton and Sussex Medical School, University of Sussex,Sackler Centre for Consciousness Science, University of Sussex, Falmer,Sussex Partnership National Health Service Trust, Brighton, United Kingdom
| | - Mara Cercignani
- Brighton and Sussex Medical School, University of Sussex,Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy
| | - Neil A. Harrison
- Brighton and Sussex Medical School, University of Sussex,Sackler Centre for Consciousness Science, University of Sussex, Falmer,Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy,Address correspondence to Neil A. Harrison, M.B.B.S., Ph.D., University of Sussex, Clinical Imaging Sciences Centre, Brighton & Sussex Medical School, Falmer BN1 9RR, United Kingdom
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Promteangtrong C, Kolber M, Ramchandra P, Moghbel M, Houshmand S, Schöll M, Bai H, Werner TJ, Alavi A, Buchpiguel C. Multimodality Imaging Approach in Alzheimer disease. Part I: Structural MRI, Functional MRI, Diffusion Tensor Imaging and Magnetization Transfer Imaging. Dement Neuropsychol 2015; 9:318-329. [PMID: 29213981 PMCID: PMC5619314 DOI: 10.1590/1980-57642015dn94000318] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The authors make a complete review of the potential clinical applications of
traditional and novel magnetic resonance imaging (MRI) techniques in the
evaluation of patients with Alzheimer's disease, including structural MRI,
functional MRI, diffusion tension imaging and magnetization transfer
imaging.
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Affiliation(s)
| | - Marcus Kolber
- Department of Radiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Priya Ramchandra
- Department of Radiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Mateen Moghbel
- Stanford University School of Medicine, Stanford, California
| | - Sina Houshmand
- Department of Radiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Michael Schöll
- Karolinska Institutet, Alzheimer Neurobiology Center, Stockholm, Sweden
| | - Halbert Bai
- Department of Radiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Thomas J Werner
- Department of Radiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Abass Alavi
- Department of Radiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Carlos Buchpiguel
- Nuclear Medicine Service, Instituto do Cancer do Estado de São Paulo, University of São Paulo, São Paulo, Brazil.,Nuclear Medicine Center, Radiology Institute, University of São Paulo General Hospital , São Paulo, Brazil
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31
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Delli Castelli D, Ferrauto G, Di Gregorio E, Terreno E, Aime S. Sensitive MRI detection of internalized T1 contrast agents using magnetization transfer contrast. NMR IN BIOMEDICINE 2015; 28:1663-1670. [PMID: 26474109 DOI: 10.1002/nbm.3423] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 09/03/2015] [Accepted: 09/06/2015] [Indexed: 06/05/2023]
Abstract
This work addresses the possibility of using Magnetization Transfer Contrast (MTC) for an improved MRI detection of T1 relaxation agents. The need to improve the detection threshold of MRI agents is particularly stringent when the contrast agents failed to accumulate to the proper extent in targeting procedures. The herein reported approach is based on the T1 dependence of MT contrast. It has been assessed that MT contrast can allow the detection of a Gd-containing agent at a lower detection threshold than the one accessible by acquiring T1W images. Measurements have been carried out either in TS/A cells or in vivo in a syngeneic murine breast cancer model. The reported data showed that in cellular experiments the MTC method displays a better sensitivity with respect to the common T1W experiments. In particular, the reached detection threshold allowed the visualization of samples containing only 2% of Gd-labeled cells diluted in unlabeled cells. In vivo experiments displayed a more diversified scheme. In particular, the tumor region showed two distinct behaviors accordingly with the localization of the imaging probe. The probe located in the tumor core could be detected to the same extent either by T1w or MTC contrast. Conversely, the agent located in the tumor rim was detected with a larger sensitivity by the MTC method herein described.
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Affiliation(s)
- Daniela Delli Castelli
- Molecular & Preclinical Imaging Centers, Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Giuseppe Ferrauto
- Molecular & Preclinical Imaging Centers, Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Enza Di Gregorio
- Molecular & Preclinical Imaging Centers, Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Enzo Terreno
- Molecular & Preclinical Imaging Centers, Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
- IBB-CNR- UOS, University of Torino, Torino, Italy
| | - Silvio Aime
- Molecular & Preclinical Imaging Centers, Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
- IBB-CNR- UOS, University of Torino, Torino, Italy
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32
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Harrison NA, Cooper E, Dowell NG, Keramida G, Voon V, Critchley HD, Cercignani M. Quantitative Magnetization Transfer Imaging as a Biomarker for Effects of Systemic Inflammation on the Brain. Biol Psychiatry 2015; 78:49-57. [PMID: 25526971 PMCID: PMC4503794 DOI: 10.1016/j.biopsych.2014.09.023] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 09/12/2014] [Accepted: 09/30/2014] [Indexed: 11/17/2022]
Abstract
BACKGROUND Systemic inflammation impairs brain function and is increasingly implicated in the etiology of common mental illnesses, particularly depression and Alzheimer's disease. Immunotherapies selectively targeting proinflammatory cytokines demonstrate efficacy in a subset of patients with depression. However, efforts to identify patients most vulnerable to the central effects of inflammation are hindered by insensitivity of conventional structural magnetic resonance imaging. METHODS We used quantitative magnetization transfer (qMT) imaging, a magnetic resonance imaging technique that enables quantification of changes in brain macromolecular density, together with experimentally induced inflammation to investigate effects of systemic inflammatory challenge on human brain microstructure. Imaging with qMT was performed in 20 healthy participants after typhoid vaccination and saline control injection. An additional 20 participants underwent fluorodeoxyglucose positron emission tomography following the same inflammatory challenge. RESULTS The qMT data demonstrated that inflammation induced a rapid change in brain microstructure, reflected in increased magnetization exchange from free (water) to macromolecular-bound protons, within a discrete region of insular cortex implicated in representing internal physiologic states including inflammation. The functional significance of this change in insular microstructure was demonstrated by correlation with inflammation-induced fatigue and fluorodeoxyglucose positron emission tomography imaging, which revealed increased resting glucose metabolism within this region following the same inflammatory challenge. CONCLUSIONS Together these observations highlight a novel structural biomarker of the central physiologic and behavioral effects of mild systemic inflammation. The widespread clinical availability of magnetic resonance imaging supports the viability of qMT imaging as a clinical biomarker in trials of immunotherapeutics, both to identify patients vulnerable to the effects of systemic inflammation and to monitor neurobiological responses.
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Affiliation(s)
- Neil A Harrison
- Brighton and Sussex Medical School, University of Sussex, Brighton.; Sackler Centre for Consciousness Science, University of Sussex, Falmer.; Sussex Partnership National Health Service Trust, Brighton..
| | - Ella Cooper
- Brighton and Sussex Medical School, University of Sussex, Brighton
| | | | - Georgia Keramida
- Brighton and Sussex Medical School, University of Sussex, Brighton
| | - Valerie Voon
- Department of Psychiatry, University of Cambridge, Cambridge, United Kingdom.; Cambridge and Peterborough NHS Foundation Trust, Cambridge, United Kingdom
| | - Hugo D Critchley
- Brighton and Sussex Medical School, University of Sussex, Brighton.; Sackler Centre for Consciousness Science, University of Sussex, Falmer.; Sussex Partnership National Health Service Trust, Brighton
| | - Mara Cercignani
- Brighton and Sussex Medical School, University of Sussex, Brighton.; Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy
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Tambasco N, Nigro P, Romoli M, Simoni S, Parnetti L, Calabresi P. Magnetization transfer MRI in dementia disorders, Huntington's disease and parkinsonism. J Neurol Sci 2015; 353:1-8. [PMID: 25891828 DOI: 10.1016/j.jns.2015.03.025] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2015] [Revised: 02/21/2015] [Accepted: 03/16/2015] [Indexed: 01/10/2023]
Abstract
Magnetic resonance imaging is the most used technique of neuroimaging. Using recent advances in magnetic resonance application it is possible to investigate several changes in neurodegenerative disease. Among different techniques, magnetization-transfer imaging (MTI), a magnetic resonance acquisition protocol assessing the magnetization exchange between protons bound to water and those bound to macromolecules, is able to identify microstructural brain tissue changes peculiar of neurodegenerative diseases. This review provides a report on the MTI technique and its use in the dementia disorders, Huntington's disease and parkinsonisms, comprehensive of the predictive values of MTI in the identification of early-phase disease.
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Affiliation(s)
- Nicola Tambasco
- Clinica Neurologica, Azienda Ospedaliera-Università di Perugia, Perugia, Italy.
| | - Pasquale Nigro
- Clinica Neurologica, Azienda Ospedaliera-Università di Perugia, Perugia, Italy
| | - Michele Romoli
- Clinica Neurologica, Azienda Ospedaliera-Università di Perugia, Perugia, Italy
| | - Simone Simoni
- Clinica Neurologica, Azienda Ospedaliera-Università di Perugia, Perugia, Italy
| | - Lucilla Parnetti
- Clinica Neurologica, Azienda Ospedaliera-Università di Perugia, Perugia, Italy
| | - Paolo Calabresi
- Clinica Neurologica, Azienda Ospedaliera-Università di Perugia, Perugia, Italy; IRCCS Fondazione Santa Lucia, Roma, Italy
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Turati L, Moscatelli M, Mastropietro A, Dowell NG, Zucca I, Erbetta A, Cordiglieri C, Brenna G, Bianchi B, Mantegazza R, Cercignani M, Baggi F, Minati L. In vivo quantitative magnetization transfer imaging correlates with histology during de- and remyelination in cuprizone-treated mice. NMR IN BIOMEDICINE 2015; 28:327-337. [PMID: 25639498 DOI: 10.1002/nbm.3253] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Revised: 11/27/2014] [Accepted: 11/29/2014] [Indexed: 06/04/2023]
Abstract
The pool size ratio measured by quantitative magnetization transfer MRI is hypothesized to closely reflect myelin density, but their relationship has so far been confirmed mostly in ex vivo conditions. We investigate the correspondence between this parameter measured in vivo at 7.0 T, with Black Gold II staining for myelin fibres, and with myelin basic protein and beta-tubulin immunofluorescence in a hybrid longitudinal study of C57BL/6 and SJL/J mice treated with cuprizone, a neurotoxicant causing relatively selective myelin loss followed by spontaneous remyelination upon treatment suspension. Our results confirm that pool size ratio measurements correlate with myelin content, with the correlation coefficient depending on strain and staining method, and demonstrate the in vivo applicability of this MRI technique to experimental mouse models of multiple sclerosis.
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Affiliation(s)
- Laura Turati
- Neuroimmunology and Neuromuscular Diseases Unit, Fondazione IRCCS Istituto Neurologico 'Carlo Besta', Milan, Italy
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Malyarenko DI, Zimmermann EM, Adler J, Swanson SD. Magnetization transfer in lamellar liquid crystals. Magn Reson Med 2014; 72:1427-34. [PMID: 24258798 PMCID: PMC4028438 DOI: 10.1002/mrm.25034] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 09/18/2013] [Accepted: 10/15/2013] [Indexed: 11/11/2022]
Abstract
PURPOSE This study examines the relationship between quantitative magnetization transfer (qMT) parameters and the molecular composition of a model lamellar liquid crystal (LLC) system composed of 1-decyl alcohol (decanol), sodium dodecyl sulfate (SDS), and water. METHODS Samples were made within a stable lamellar mesophase to provide different ratios of total semisolid protons (SDS + decanol) to water protons. Data were collected as a function of radiofrequency power, frequency offset, and temperature. qMT parameters were estimated by fitting a standard model to the data. Fitting results of four different semisolid line shapes were compared. RESULTS A super-Lorentzian line shape for the semisolid component provided the best fit. The estimated amount of semisolids was proportional to the ratio of decanol-to-water protons. Other qMT parameters exhibited nonlinear dependence on sample composition. Magnetization transfer ratio (MTR) was a linear function of the semisolid fraction over a limited range of decanol concentration. CONCLUSION In LLC samples, MT between semisolid and water originates from intramolecular nOe among decanol aliphatic chain protons followed by proton exchange between decanol hydroxyl and water. Exchange kinetics is influenced by SDS, although SDS protons do not participate in MT. These studies provide clinically relevant range of semisolid fraction proportional to detected MTR.
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Affiliation(s)
| | - Ellen M. Zimmermann
- Department of Internal Medicine - Gastroenterology, University of Michigan, Ann Arbor, MI, United States
| | - Jeremy Adler
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI, United States
| | - Scott D. Swanson
- Department of Radiology, University of Michigan, Ann Arbor, MI, United States
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Adlard PA, Tran BA, Finkelstein DI, Desmond PM, Johnston LA, Bush AI, Egan GF. A review of β-amyloid neuroimaging in Alzheimer's disease. Front Neurosci 2014; 8:327. [PMID: 25400539 PMCID: PMC4215612 DOI: 10.3389/fnins.2014.00327] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 09/27/2014] [Indexed: 12/20/2022] Open
Abstract
Alzheimer's disease (AD) is the most common cause of dementia worldwide. As advancing age is the greatest risk factor for developing AD, the number of those afflicted is expected to increase markedly with the aging of the world's population. The inability to definitively diagnose AD until autopsy remains an impediment to establishing effective targeted treatments. Neuroimaging has enabled in vivo visualization of pathological changes in the brain associated with the disease, providing a greater understanding of its pathophysiological development and progression. However, neuroimaging biomarkers do not yet offer clear advantages over current clinical diagnostic criteria for them to be accepted into routine clinical use. Nonetheless, current insights from neuroimaging combined with the elucidation of biochemical and molecular processes in AD are informing the ongoing development of new imaging techniques and their application. Much of this research has been greatly assisted by the availability of transgenic mouse models of AD. In this review we summarize the main efforts of neuroimaging in AD in humans and in mouse models, with a specific focus on β-amyloid, and discuss the potential of new applications and novel approaches.
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Affiliation(s)
- Paul A. Adlard
- Division of Mental Health, The Florey Institute of Neuroscience and Mental Health, University of MelbourneParkville, VIC, Australia
| | - Bob A. Tran
- Department of Radiology, University of MelbourneParkville, VIC, Australia
| | - David I. Finkelstein
- Division of Mental Health, The Florey Institute of Neuroscience and Mental Health, University of MelbourneParkville, VIC, Australia
| | - Patricia M. Desmond
- Department of Radiology, University of MelbourneParkville, VIC, Australia
- Department of Radiology, The Royal Melbourne HospitalParkville, VIC, Australia
| | - Leigh A. Johnston
- Division of Mental Health, The Florey Institute of Neuroscience and Mental Health, University of MelbourneParkville, VIC, Australia
- Department of Electrical and Electronic Engineering, University of MelbourneParkville, VIC, Australia
| | - Ashley I. Bush
- Division of Mental Health, The Florey Institute of Neuroscience and Mental Health, University of MelbourneParkville, VIC, Australia
| | - Gary F. Egan
- Monash Biomedical Imaging, Monash UniversityClayton, VIC, Australia
- School of Psychology and Psychiatry, Monash UniversityClayton, VIC, Australia
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Seiler S, Pirpamer L, Hofer E, Duering M, Jouvent E, Fazekas F, Mangin JF, Chabriat H, Dichgans M, Ropele S, Schmidt R. Magnetization transfer ratio relates to cognitive impairment in normal elderly. Front Aging Neurosci 2014; 6:263. [PMID: 25309438 PMCID: PMC4174770 DOI: 10.3389/fnagi.2014.00263] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Accepted: 09/11/2014] [Indexed: 01/15/2023] Open
Abstract
Magnetization transfer imaging (MTI) can detect microstructural brain tissue changes and may be helpful in determining age-related cerebral damage. We investigated the association between the magnetization transfer ratio (MTR) in gray and white matter (WM) and cognitive functioning in 355 participants of the Austrian stroke prevention family study (ASPS-Fam) aged 38-86 years. MTR maps were generated for the neocortex, deep gray matter structures, WM hyperintensities, and normal appearing WM (NAWM). Adjusted mixed models determined whole brain and lobar cortical MTR to be directly and significantly related to performance on tests of memory, executive function, and motor skills. There existed an almost linear dose-effect relationship. MTR of deep gray matter structures and NAWM correlated to executive functioning. All associations were independent of demographics, vascular risk factors, focal brain lesions, and cortex volume. Further research is needed to understand the basis of this association at the tissue level, and to determine the role of MTR in predicting cognitive decline and dementia.
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Affiliation(s)
- Stephan Seiler
- Department of Neurology, Medical University of Graz , Graz , Austria
| | - Lukas Pirpamer
- Department of Neurology, Medical University of Graz , Graz , Austria
| | - Edith Hofer
- Department of Neurology, Medical University of Graz , Graz , Austria ; Institute of Medical Informatics, Statistics and Documentation, Medical University of Graz , Graz , Austria
| | - Marco Duering
- Institute for Stroke and Dementia Research, Klinikum der Universität München, Ludwig-Maximilians-University , Munich , Germany
| | - Eric Jouvent
- Department of Neurology, CHU Lariboisière , Paris , France
| | - Franz Fazekas
- Department of Neurology, Medical University of Graz , Graz , Austria
| | | | | | - Martin Dichgans
- Institute for Stroke and Dementia Research, Klinikum der Universität München, Ludwig-Maximilians-University , Munich , Germany ; German Center for Neurodegenerative Diseases (DZNE) , Munich , Germany ; Munich Cluster for Systems Neurology (SyNergy) , Munich , Germany
| | - Stefan Ropele
- Department of Neurology, Medical University of Graz , Graz , Austria
| | - Reinhold Schmidt
- Department of Neurology, Medical University of Graz , Graz , Austria
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Yin C, Li S, Zhao W, Feng J. Brain imaging of mild cognitive impairment and Alzheimer's disease. Neural Regen Res 2014; 8:435-44. [PMID: 25206685 PMCID: PMC4146132 DOI: 10.3969/j.issn.1673-5374.2013.05.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Accepted: 12/03/2012] [Indexed: 11/18/2022] Open
Abstract
The rapidly increasing prevalence of cognitive impairment and Alzheimer's disease has the potential to create a major worldwide healthcare crisis. Structural MRI studies in patients with Alzheimer's disease and mild cognitive impairment are currently attracting considerable interest. It is extremely important to study early structural and metabolic changes, such as those in the hippocampus, entorhinal cortex, and gray matter structures in the medial temporal lobe, to allow the early detection of mild cognitive impairment and Alzheimer's disease. The microstructural integrity of white matter can be studied with diffusion tensor imaging. Increased mean diffusivity and decreased fractional anisotropy are found in subjects with white matter damage. Functional imaging studies with positron emission tomography tracer compounds enable detection of amyloid plaques in the living brain in patients with Alzheimer's disease. In this review, we will focus on key findings from brain imaging studies in mild cognitive impairment and Alzheimer's disease, including structural brain changes studied with MRI and white matter changes seen with diffusion tensor imaging, and other specific imaging methodologies will also be discussed.
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Affiliation(s)
- Changhao Yin
- Department of Neurology, the First Hospital of Jilin University, Changchun 130021, Jilin Province, China ; Department of Neurology, Hongqi Hospital, Mudanjiang Medical University, Mudanjiang 157004, Heilongjiang Province, China
| | - Siou Li
- Department of Neurology, Hongqi Hospital, Mudanjiang Medical University, Mudanjiang 157004, Heilongjiang Province, China
| | - Weina Zhao
- Department of Neurology, Hongqi Hospital, Mudanjiang Medical University, Mudanjiang 157004, Heilongjiang Province, China
| | - Jiachun Feng
- Department of Neurology, the First Hospital of Jilin University, Changchun 130021, Jilin Province, China
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39
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Chen Y, Pham TD. Development of a brain MRI-based hidden Markov model for dementia recognition. Biomed Eng Online 2014; 12 Suppl 1:S2. [PMID: 24564961 PMCID: PMC4028867 DOI: 10.1186/1475-925x-12-s1-s2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Dementia is an age-related cognitive decline which is indicated by an early degeneration of cortical and sub-cortical structures. Characterizing those morphological changes can help to understand the disease development and contribute to disease early prediction and prevention. But modeling that can best capture brain structural variability and can be valid in both disease classification and interpretation is extremely challenging. The current study aimed to establish a computational approach for modeling the magnetic resonance imaging (MRI)-based structural complexity of the brain using the framework of hidden Markov models (HMMs) for dementia recognition. METHODS Regularity dimension and semi-variogram were used to extract structural features of the brains, and vector quantization method was applied to convert extracted feature vectors to prototype vectors. The output VQ indices were then utilized to estimate parameters for HMMs. To validate its accuracy and robustness, experiments were carried out on individuals who were characterized as non-demented and mild Alzheimer's diseased. Four HMMs were constructed based on the cohort of non-demented young, middle-aged, elder and demented elder subjects separately. Classification was carried out using a data set including both non-demented and demented individuals with a wide age range. RESULTS The proposed HMMs have succeeded in recognition of individual who has mild Alzheimer's disease and achieved a better classification accuracy compared to other related works using different classifiers. Results have shown the ability of the proposed modeling for recognition of early dementia. CONCLUSION The findings from this research will allow individual classification to support the early diagnosis and prediction of dementia. By using the brain MRI-based HMMs developed in our proposed research, it will be more efficient, robust and can be easily used by clinicians as a computer-aid tool for validating imaging bio-markers for early prediction of dementia.
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40
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PET Neuroimaging: The White Elephant Packs His Trunk? Neuroimage 2014; 84:1094-100. [DOI: 10.1016/j.neuroimage.2013.08.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Revised: 08/07/2013] [Accepted: 08/11/2013] [Indexed: 01/30/2023] Open
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Bigot C, Vanhoutte G, Verhoye M, Van der Linden A. Magnetization transfer contrast imaging reveals amyloid pathology in Alzheimer's disease transgenic mice. Neuroimage 2013; 87:111-9. [PMID: 24188815 DOI: 10.1016/j.neuroimage.2013.10.056] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Revised: 10/19/2013] [Accepted: 10/26/2013] [Indexed: 12/18/2022] Open
Abstract
The presence of amyloid plaques in the brain is one of the pathological hallmarks of Alzheimer's disease, which might already be present in the early stage of the disease. Therefore it is important to track amyloid plaques as early as possible. In this paper, we report magnetization transfer contrast magnetic resonance imaging (MTC MRI) as a novel approach to detect amyloid plaques in vivo. Two mice models, APP/PS1 and BRI, developing amyloid pathology were investigated with MTC MRI, T2 relaxation measurements and immunohistochemistry (IHC). MT-ratios of several brain regions were compared to T2-values and correlated with quantitative IHC, revealing amyloid load and gliosis in different brain regions. APP/PS1 mice develop large compact plaques, resembling late stage Alzheimer's disease, while rather small and diffuse plaques are deposited in BRI mice, reflecting early stage of Alzheimer's disease. We found significantly higher MT-ratio's in the brain of APP/PS1 mice as compared to their controls and similar trends in BRI mice. A region based MT-ratio and IHC analysis and correlations between MT-ratios and quantitative IHC indicate amyloid plaques as the main substrate for altered MT-ratios in transgenic animals. We additionally demonstrated the improved sensitivity of MTC MRI to amyloid pathology as compared to traditional T2 relaxation measurements. Our results suggest that MTC MRI reveals extensive, and potentially even early amyloid pathology. Further unraveling the MT-effect of each pathological feature during each stage of AD might indicate MTC MRI as a useful diagnostic technique.
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Affiliation(s)
- Christian Bigot
- Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 Uc, 2610 Wilrijk, Antwerp, Belgium.
| | - Greetje Vanhoutte
- Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 Uc, 2610 Wilrijk, Antwerp, Belgium.
| | - Marleen Verhoye
- Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 Uc, 2610 Wilrijk, Antwerp, Belgium.
| | - Annemie Van der Linden
- Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 Uc, 2610 Wilrijk, Antwerp, Belgium.
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42
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Mascalchi M, Ginestroni A, Bessi V, Toschi N, Padiglioni S, Ciulli S, Tessa C, Giannelli M, Bracco L, Diciotti S. Regional analysis of the magnetization transfer ratio of the brain in mild Alzheimer disease and amnestic mild cognitive impairment. AJNR Am J Neuroradiol 2013; 34:2098-104. [PMID: 23744687 DOI: 10.3174/ajnr.a3568] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Manually drawn VOI-based analysis shows a decrease in magnetization transfer ratio in the hippocampus of patients with Alzheimer disease. We investigated with whole-brain voxelwise analysis the regional changes of the magnetization transfer ratio in patients with mild Alzheimer disease and patients with amnestic mild cognitive impairment. MATERIALS AND METHODS Twenty patients with mild Alzheimer disease, 27 patients with amnestic mild cognitive impairment, and 30 healthy elderly control subjects were examined with high-resolution T1WI and 3-mm-thick magnetization transfer images. Whole-brain voxelwise analysis of magnetization transfer ratio maps was performed by use of Statistical Parametric Mapping 8 software and was supplemented by the analysis of the magnetization transfer ratio in FreeSurfer parcellation-derived VOIs. RESULTS Voxelwise analysis showed 2 clusters of significantly decreased magnetization transfer ratio in the left hippocampus and amygdala and in the left posterior mesial temporal cortex (fusiform gyrus) of patients with Alzheimer disease as compared with control subjects but no difference between patients with amnestic mild cognitive impairment and either patients with Alzheimer disease or control subjects. VOI analysis showed that the magnetization transfer ratio in the hippocampus and amygdala was significantly lower (bilaterally) in patients with Alzheimer disease when compared with control subjects (ANOVA with Bonferroni correction, at P < .05). Mean magnetization transfer ratio values in the hippocampus and amygdala in patients with amnestic mild cognitive impairment were between those of healthy control subjects and those of patients with mild Alzheimer disease. Support vector machine-based classification demonstrated improved classification performance after inclusion of magnetization transfer ratio-related features, especially between patients with Alzheimer disease versus healthy subjects. CONCLUSIONS Bilateral but asymmetric decrease of magnetization transfer ratio reflecting microstructural changes of the residual GM is present not only in the hippocampus but also in the amygdala in patients with mild Alzheimer disease.
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Affiliation(s)
- M Mascalchi
- Quantitative and Functional Neuroradiology Research Unit, Department of Experimental and Clinical Biomedical Sciences
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43
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Mascalchi M, Toschi N, Ginestroni A, Giannelli M, Nicolai E, Aiello M, Soricelli A, Diciotti S. Gender, age-related, and regional differences of the magnetization transfer ratio of the cortical and subcortical brain gray matter. J Magn Reson Imaging 2013; 40:360-6. [PMID: 24923993 DOI: 10.1002/jmri.24355] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 07/29/2013] [Indexed: 12/14/2022] Open
Abstract
PURPOSE To explore gender, age-related, and regional differences of magnetization transfer ratio (MTR) of brain cortical and subcortical gray matter (GM). MATERIALS AND METHODS In all, 102 healthy subjects (51 women and 51 men; range 25-84 years) were examined with 3-mm thick MT images. We assessed MTR in automatically segmented GM structures including frontal, parietal-insular, temporal, and occipital cortex, caudate, pallidus and putamen, and cerebellar cortex. A general linear model analysis was conducted to ascertain the linear and quadratic relationship among the MTR and gender, age, and anatomical structure. RESULTS The effect of gender was borderline (P = 0.07) in all GM structures (with higher MTR values in men), whereas age showed a significant linear as well as quadratic effect in all cortical and subcortical GM structures (P ≤ 0.001). Quadratic age-related decrease in MTR began at about 40 years of age. Mean and standard deviation (SD) of MTR had the following decreasing order: thalamus (58.3 + 0.8), pallidus (56.8 ± 1.3), caudate (55.5 ± 1.6) and putamen (54.6 ± 1.1); temporal (56.8 ± 0.9), parietal-insular (56.8 ± 1.1), frontal (56.5 ± 1.1), occipital (55.4 ± 1.0) and cerebellar (53.2 ± 1.0) cortex. In post-hoc testing, all regional pairwise differences were statistically significant except pallidus vs. temporal or parietal-insular cortex, caudate vs. occipital cortex, frontal vs. parietal-insular or temporal cortex. CONCLUSION MTR of the cortical and subcortical brain GM structures decreases quadratically after midlife and shows significant regional differences.
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Affiliation(s)
- Mario Mascalchi
- Quantitative and Functional Neuroradiology Program at Meyer Children's Hospital and Careggi Hospital of Florence, Department of Experimental and Clinical Biomedical Sciences, University of Florence, Florence, Italy
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44
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Weiler M, Cendes F, Balthazar MLF. Comparing regional brain atrophy in mild cognitive impairment and Alzheimer’s disease. Neurodegener Dis Manag 2013. [DOI: 10.2217/nmt.13.49] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
SUMMARY Neuroimaging has assumed an active role in the diagnosis of Alzheimer’s disease (AD) and other dementias. Structural MRI can estimate changes in specific brain structures relative to normal and pathological aging such as volume, cortical thickness and gray matter density. Several different structural MRI methods can be used to identify neuropathology and point to an early atrophy in medial temporal lobe structures in patients with AD and amnestic mild cognitive impairment, especially in the entorhinal cortex and hippocampus. These alterations in medial temporal lobe structures were also considered evidence for neurodegeneration, even in preclinical AD. However, evaluation in other areas such as ventricular enlargement and precuneus may help the diagnosis, even in the early stages of the disease. Currently, neuroimaging is an excellent tool for increasing diagnostic accuracy, but does not substitute a careful clinical and neuropsychological evaluation. In this article, our objective is to gather information about different structural MRI-based methods that could offer objective measures of brain structures and increase the diagnostic power of mild cognitive impairment and AD.
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Affiliation(s)
- Marina Weiler
- Neuroimaging Laboratory, Department of Neurology, Medical Sciences School, University of Campinas, Brazil
| | - Fernando Cendes
- Neuroimaging Laboratory, Department of Neurology, Medical Sciences School, University of Campinas, Brazil
| | - Marcio LF Balthazar
- Neuroimaging Laboratory, Department of Neurology, Medical Sciences School, University of Campinas, Brazil
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45
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Cosottini M, Cecchi P, Piazza S, Pesaresi I, Fabbri S, Diciotti S, Mascalchi M, Siciliano G, Bonuccelli U. Mapping cortical degeneration in ALS with magnetization transfer ratio and voxel-based morphometry. PLoS One 2013; 8:e68279. [PMID: 23874570 PMCID: PMC3706610 DOI: 10.1371/journal.pone.0068279] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2013] [Accepted: 05/27/2013] [Indexed: 12/02/2022] Open
Abstract
Pathological and imaging data indicate that amyotrophic lateral sclerosis (ALS) is a multisystem disease involving several cerebral cortical areas. Advanced quantitative magnetic resonance imaging (MRI) techniques enable to explore in vivo the volume and microstructure of the cerebral cortex in ALS. We studied with a combined voxel-based morphometry (VBM) and magnetization transfer (MT) imaging approach the capability of MRI to identify the cortical areas affected by neurodegeneration in ALS patients. Eighteen ALS patients and 18 age-matched healthy controls were examined on a 1.5T scanner using a high-resolution 3D T1 weighted spoiled gradient recalled sequence with and without MT saturation pulse. A voxel-based analysis (VBA) was adopted in order to automatically compute the regional atrophy and MT ratio (MTr) changes of the entire cerebral cortex. By using a multimodal image analysis MTr was adjusted for local gray matter (GM) atrophy to investigate if MTr changes can be independent of atrophy of the cerebral cortex. VBA revealed several clusters of combined GM atrophy and MTr decrease in motor-related areas and extra-motor frontotemporal cortex. The multimodal image analysis identified areas of isolated MTr decrease in premotor and extra-motor frontotemporal areas. VBM and MTr are capable to detect the distribution of neurodegenerative alterations in the cortical GM of ALS patients, supporting the hypothesis of a multi-systemic involvement in ALS. MT imaging changes exist beyond volume loss in frontotemporal cortices.
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Affiliation(s)
- Mirco Cosottini
- Department of Neuroscience, University of Pisa, Pisa, Italy.
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46
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Dowell NG, Ruest T, Evans SL, King SL, Tabet N, Tofts PS, Rusted JM. MRI of carriers of the apolipoprotein E e4 allele-evidence for structural differences in normal-appearing brain tissue in e4+ relative to e4- young adults. NMR IN BIOMEDICINE 2013; 26:674-682. [PMID: 23364916 DOI: 10.1002/nbm.2912] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Revised: 11/21/2012] [Accepted: 12/05/2012] [Indexed: 06/01/2023]
Abstract
Apolipoprotein E is a protein involved in cholesterol and lipid transport. The gene coding for this protein has three different alleles: e2, e3 and e4. The e4 allele is recognised as a significant risk factor for the development of Alzheimer's disease in later life. Paradoxically, behavioural and functional evidence has demonstrated that the e4 allele may confer a cognitive advantage to the carrier in youth. In this article, a range of sophisticated and novel structural imaging techniques were used to identify subtle differences in the brain tissue of groups of young e4 and homozygous e3 carriers that might support this paradox. Using voxel-based morphometry of high-resolution structural MR images, we identified a higher white matter volume ratio in e4 relative to homozygous e3 carriers. Furthermore, diffusion tensor imaging and tract-based spatial statistics studies identified increases in axial diffusivity and mode of anisotropy in carriers of the e4 allele. In addition, quantitative magnetisation transfer data were analysed using tract-based spatial statistics. Evidence of a trend towards an increased transverse relaxation time of the bound proton pool was detected in e4 carriers, indicative of altered white matter composition. These changes were found to correlate with indices of cognitive performance across the two groups, supporting the notion that such subtle differences in white matter integrity may confer neural advantages that contribute to cognitive outcomes and, potentially, to performance differences, such as observed here in a test of verbal fluency and reported previously by other researchers. Copyright © 2013 John Wiley & Sons, Ltd.
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Affiliation(s)
- Nicholas G Dowell
- Brighton and Sussex Medical School (BSMS), Clinical Imaging Sciences Centre, Brighton, Sussex, UK.
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47
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Chen Y, Pham TD. Sample entropy and regularity dimension in complexity analysis of cortical surface structure in early Alzheimer's disease and aging. J Neurosci Methods 2013; 215:210-7. [PMID: 23558334 DOI: 10.1016/j.jneumeth.2013.03.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2012] [Revised: 03/21/2013] [Accepted: 03/22/2013] [Indexed: 11/16/2022]
Abstract
We apply for the first time the sample entropy (SampEn) and regularity dimension model for measuring signal complexity to quantify the structural complexity of the brain on MRI. The concept of the regularity dimension is based on the theory of chaos for studying nonlinear dynamical systems, where power laws and entropy measure are adopted to develop the regularity dimension for modeling a mathematical relationship between the frequencies with which information about signal regularity changes in various scales. The sample entropy and regularity dimension of MRI-based brain structural complexity are computed for early Alzheimer's disease (AD) elder adults and age and gender-matched non-demented controls, as well as for a wide range of ages from young people to elder adults. A significantly higher global cortical structure complexity is detected in AD individuals (p<0.001). The increase of SampEn and the regularity dimension are also found to be accompanied with aging which might indicate an age-related exacerbation of cortical structural irregularity. The provided model can be potentially used as an imaging bio-marker for early prediction of AD and age-related cognitive decline.
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Affiliation(s)
- Ying Chen
- Aizu Research Cluster for Medical Engineering and Informatics, Research Center for Advanced Information Science and Technology, The University of Aizu, Aizuwakamatsu, Fukushima 965-8580, Japan.
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Battistella G, Niederhauser J, Fornari E, Hippolyte L, Gronchi Perrin A, Lesca G, Forzano F, Hagmann P, Vingerhoets FJG, Draganski B, Maeder P, Jacquemont S. Brain structure in asymptomatic FMR1 premutation carriers at risk for fragile X-associated tremor/ataxia syndrome. Neurobiol Aging 2013; 34:1700-7. [PMID: 23298734 DOI: 10.1016/j.neurobiolaging.2012.12.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Accepted: 12/03/2012] [Indexed: 01/20/2023]
Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS), a late-onset movement disorder affecting FMR1 premutation carriers, is associated with cerebral and cerebellar lesions. The aim of this study was to test whether computational anatomy can detect similar patterns in asymptomatic FMR1 premutation carriers (mean age 46.7 years) with qualitatively normal -appearing grey and white matter on brain MRI. We used a multimodal imaging protocol to characterize brain anatomy by automated assessment of gray matter volume and white matter properties. Structural changes in the hippocampus and in the cerebellar motor network with decreased gray matter volume in lobule VI and white matter alterations of the corresponding afferent projections through the middle cerebellar peduncles are demonstrated. Diffuse subcortical white matter changes in both hemispheres, without corresponding gray matter alterations, are only identified through age × group interactions. We interpret the hippocampal fimbria and cerebellar changes as early alterations with a possible neurodevelopmental origin. In contrast, progression of the diffuse cerebral hemispheric white matter changes suggests a neurodegenerative process, leading to late-onset lesions, which may mark the imminent onset of FXTAS.
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Affiliation(s)
- Giovanni Battistella
- Department of Radiology, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland
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Wiest R, Burren Y, Hauf M, Schroth G, Pruessner J, Zbinden M, Cattapan-Ludewig K, Kiefer C. Classification of mild cognitive impairment and Alzheimer disease using model-based MR and magnetization transfer imaging. AJNR Am J Neuroradiol 2012; 34:740-6. [PMID: 23064592 DOI: 10.3174/ajnr.a3307] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Early stratification of degenerative processes is a prerequisite to warrant therapeutic options in prodromal Alzheimer disease. Our aim was to investigate differences in cerebral macromolecular tissue composition between patients with AD, mild cognitive impairment, and age- and sex-matched healthy controls by using model-based magnetization transfer with a binary spin-bath magnetization transfer model and magnetization transfer ratio at 1.5 T. MATERIALS AND METHODS We investigated patients with de novo AD (n=18), MCI (n=18), and CTRLs (n=18). A region-of-interest analysis of the entorhinal cortex, hippocampal head and body, insula, and temporal neocortex was performed with fuzzy clustering to associate every subregion to a cluster representative for each group. RESULTS Cluster analysis achieved a concordance of 0.92 (50 of 54 subjects) between a combination of the calculated mMT parameters (kf,kr,T2r,F,T2f) in the entorhinal cortex and the neuropsychological diagnosis. The sensitivity and specificity for the discrimination of AD from MCI reached 1 and 0.94, with a positive predictive value of 0.95 and a negative predictive value of 1. Compared with mMT, the concordance for MTR was 0.83 (45 of 54 subjects) with a lower specificity of 0.5 and positive predictive value of 0.67 to discriminate patients with AD and MCI. CONCLUSIONS mMT imaging detects macromolecule-related alterations and allows an improved classification of patients with early AD and MCI compared with MTR.
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Affiliation(s)
- R Wiest
- Support Center for Advanced Neuroimaging, University Institute of Diagnostic and Interventional Neuroradiology, Inselspital, University of Bern, Bern, Switzerland
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