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Valenti R, Reijmer YD, Charidimou A, Boulouis G, Martinez SR, Xiong L, Fotiadis P, Jessel M, Ayres A, Riley G, Pantoni L, Edip Gurol M, Greenberg SM, Viswanathan A. Total small vessel disease burden and brain network efficiency in cerebral amyloid angiopathy. J Neurol Sci 2017; 382:10-12. [PMID: 29110998 DOI: 10.1016/j.jns.2017.09.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 08/24/2017] [Accepted: 09/11/2017] [Indexed: 10/18/2022]
Abstract
BACKGROUND Cerebral amyloid angiopathy (CAA) is associated with hemorrhagic and nonhemorrhagic markers small vessel disease (SVD). A composite score to quantify the total burden of SVD on MRI specifically for CAA patients was recently developed. Brain network alterations related to individual MRI markers of SVD in CAA were demonstrated. OBJECTIVES Considering diffusion based network measures sensitive to detect different relevant SVD-related brain injury, we investigated if increased overall SVD injury on MRI corresponds to worse global brain connectivity in CAA. METHODS Seventy-three patients (79.5% male, mean age 70.58±8.22years) with a diagnosis CAA were considered. SVD markers in total MRI SVD score included: lobar cerebral microbleeds, cortical superficial siderosis (cSS), white matter hyperintensities (WMH) and centrum semiovale-enlarged perivascular spaces. Diffusion imaging based network reconstruction was made. The associations between total MRI SVD score and global network efficiency (GNE) were analyzed. RESULTS A modest significant inverse correlation between total MRI SVD score and GNE existed (p=0.013; R2=0.07). GNE was related with the presence of cSS and moderate-severe WMHs. CONCLUSIONS An increased burden of SVD neuroimaging markers corresponds to more reductions in global brain connectivity, implying a possible cumulative effect of overall SVD markers on disrupted physiology. GNE was related with some components of the score, specifically cSS and moderate-severe WMHs.
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Affiliation(s)
- Raffaella Valenti
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA; NEUROFARBA Department, Neuroscience Section, University of Florence, Florence, Italy
| | - Yael D Reijmer
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Andreas Charidimou
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Gregoire Boulouis
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA; Université Paris-Descartes, Department of Neuroradiology, Centre Hospitalier Sainte-Anne, Paris, France
| | - Sergi Ramirez Martinez
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Li Xiong
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Panagiotis Fotiadis
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Michael Jessel
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Alison Ayres
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Grace Riley
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Leonardo Pantoni
- NEUROFARBA Department, Neuroscience Section, University of Florence, Florence, Italy
| | - M Edip Gurol
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Steven M Greenberg
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Anand Viswanathan
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA.
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102
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Charidimou A, Boulouis G, Gurol ME, Ayata C, Bacskai BJ, Frosch MP, Viswanathan A, Greenberg SM. Emerging concepts in sporadic cerebral amyloid angiopathy. Brain 2017; 140:1829-1850. [PMID: 28334869 DOI: 10.1093/brain/awx047] [Citation(s) in RCA: 313] [Impact Index Per Article: 44.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 01/17/2017] [Indexed: 12/27/2022] Open
Abstract
Sporadic cerebral amyloid angiopathy is a common, well-defined small vessel disease and a largely untreatable cause of intracerebral haemorrhage and contributor to age-related cognitive decline. The term 'cerebral amyloid angiopathy' now encompasses not only a specific cerebrovascular pathological finding, but also different clinical syndromes (both acute and progressive), brain parenchymal lesions seen on neuroimaging and a set of diagnostic criteria-the Boston criteria, which have resulted in increasingly detected disease during life. Over the past few years, it has become clear that, at the pathophysiological level, cerebral amyloid angiopathy appears to be in part a protein elimination failure angiopathy and that this dysfunction is a feed-forward process, which potentially leads to worsening vascular amyloid-β accumulation, activation of vascular injury pathways and impaired vascular physiology. From a clinical standpoint, cerebral amyloid angiopathy is characterized by individual focal lesions (microbleeds, cortical superficial siderosis, microinfarcts) and large-scale alterations (white matter hyperintensities, structural connectivity, cortical thickness), both cortical and subcortical. This review provides an interdisciplinary critical outlook on various emerging and changing concepts in the field, illustrating mechanisms associated with amyloid cerebrovascular pathology and neurological dysfunction.
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Affiliation(s)
- Andreas Charidimou
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Gregoire Boulouis
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - M Edip Gurol
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Cenk Ayata
- Neurovascular Research Laboratory, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA.,Stroke Service and Neuroscience Intensive Care Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Brian J Bacskai
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St., Charlestown, MA 02129, USA
| | - Matthew P Frosch
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St., Charlestown, MA 02129, USA.,C.S. Kubik Laboratory for Neuropathology, Department of Pathology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St., Charlestown, MA 02129, USA
| | - Anand Viswanathan
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Steven M Greenberg
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA.,Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114, 16th St., Charlestown, MA 02129, USA
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103
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Li JM, Huang LL, Liu F, Tang BS, Yan XX. Can brain impermeable BACE1 inhibitors serve as anti-CAA medicine? BMC Neurol 2017; 17:163. [PMID: 28841840 PMCID: PMC5574137 DOI: 10.1186/s12883-017-0942-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 08/14/2017] [Indexed: 12/21/2022] Open
Abstract
Background Cerebral amyloid angiopathy (CAA) is characterized by the deposition of ß-amyloid peptides (Aß) in and surrounding the wall of microvasculature in the central nervous system, together with parenchymal amyloid plaques collectively referred to as cerebral amyloidosis, which occurs in the brain commonly among the elderly and more frequently in patients with Alzheimer’s disease (AD). CAA is associated with vascular injury and may cause devastating neurological outcomes. No therapeutic approach is available for this lesion to date. Main body ß-Secretase 1 (BACE1) is the enzyme initiating Aß production. Brain permeable BACE1 inhibitors targeting primarily at the parenchymal plaque pathology are currently evaluated in clinical trials. This article presents findings in support of a role of BACE1 elevation in the development of CAA, in addition to plaque pathogenesis. The rationale, feasibility, benefit and strategic issues for developing BACE1 inhibitors against CAA are discussed. Brain impermeable compounds are considered preferable as they might exhibit sufficient anti-CAA efficacy without causing significant neuronal/synaptic side effects. Conclusion Early pharmacological intervention to the pathogenesis of CAA is expected to provide significant protection for cerebral vascular health and hence brain health. Brain impermeable BACE1 inhibitors should be optimized and tested as potential anti-CAA therapeutics.
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Affiliation(s)
- Jian-Ming Li
- Department of Neurology & Key Laboratory of Hunan Province in Neurodegenerative Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China.,Neuroscience Research Center, Changsha Medical University, Changsha, Hunan, 410219, China
| | - Li-Ling Huang
- Department of Anatomy and Neurobiology, Central South University School of Basic Medical Science, Changsha, Hunan, 410013, China
| | - Fei Liu
- Department of Neurosurgery, The Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China
| | - Bei-Sha Tang
- Department of Neurology & Key Laboratory of Hunan Province in Neurodegenerative Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China
| | - Xiao-Xin Yan
- Department of Neurology & Key Laboratory of Hunan Province in Neurodegenerative Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China. .,Department of Anatomy and Neurobiology, Central South University School of Basic Medical Science, Changsha, Hunan, 410013, China.
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104
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Greenberg SM. William M. Feinberg Award for Excellence in Clinical Stroke: Big Pictures and Small Vessels. Stroke 2017; 48:2628-2631. [PMID: 28698255 DOI: 10.1161/strokeaha.117.017246] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2017] [Revised: 06/10/2017] [Accepted: 06/22/2017] [Indexed: 01/05/2023]
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105
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Abstract
Recent advances in connectomics have led to a synthesis of perspectives regarding the brain's functional organization that reconciles classical concepts of localized specialization with an appreciation for properties that emerge from interactions across distributed functional networks. This provides a more comprehensive framework for understanding neural mechanisms of normal cognition and disease. Although fMRI has not become a routine clinical tool, research has already had important influences on clinical concepts guiding diagnosis and patient management. Here we review illustrative examples. Studies demonstrating the network plasticity possible in adults and the global consequences of even focal brain injuries or disease both have had substantial impact on modern concepts of disease evolution and expression. Applications of functional connectomics in studies of clinical populations are challenging traditional disease classifications and helping to clarify biological relationships between clinical syndromes (and thus also ways of extending indications for, or "re-purposing," current treatments). Large datasets from prospective, longitudinal studies promise to enable the discovery and validation of functional connectomic biomarkers with the potential to identify people at high risk of disease before clinical onset, at a time when treatments may be most effective. Studies of pain and consciousness have catalyzed reconsiderations of approaches to clinical management, but also have stimulated debate about the clinical meaningfulness of differences in internal perceptual or cognitive states inferred from functional connectomics or other physiological correlates. By way of a closing summary, we offer a personal view of immediate challenges and potential opportunities for clinically relevant applications of fMRI-based functional connectomics.
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Affiliation(s)
- Paul M Matthews
- Division of Brain Sciences, Department of Medicine and Centre for Neurotechnology, Imperial College London, London WC12 0NN, UK.
| | - Adam Hampshire
- Division of Brain Sciences, Department of Medicine and Centre for Neurotechnology, Imperial College London, London WC12 0NN, UK
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106
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Blair GW, Hernandez MV, Thrippleton MJ, Doubal FN, Wardlaw JM. Advanced Neuroimaging of Cerebral Small Vessel Disease. CURRENT TREATMENT OPTIONS IN CARDIOVASCULAR MEDICINE 2017. [PMID: 28620783 PMCID: PMC5486578 DOI: 10.1007/s11936-017-0555-1] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Cerebral small vessel disease (SVD) is characterised by damage to deep grey and white matter structures of the brain and is responsible for a diverse range of clinical problems that include stroke and dementia. In this review, we describe advances in neuroimaging published since January 2015, mainly with magnetic resonance imaging (MRI), that, in general, are improving quantification, observation and investigation of SVD focussing on three areas: quantifying the total SVD burden, imaging brain microstructural integrity and imaging vascular malfunction. Methods to capture ‘whole brain SVD burden’ across the spectrum of SVD imaging changes will be useful for patient stratification in clinical trials, an approach that we are already testing. More sophisticated imaging measures of SVD microstructural damage are allowing the disease to be studied at earlier stages, will help identify specific factors that are important in development of overt SVD imaging features and in understanding why specific clinical consequences may occur. Imaging vascular function will help establish the precise blood vessel and blood flow alterations at early disease stages and, together with microstructural integrity measures, may provide important surrogate endpoints in clinical trials testing new interventions. Better knowledge of SVD pathophysiology will help identify new treatment targets, improve patient stratification and may in future increase efficiency of clinical trials through smaller sample sizes or shorter follow-up periods. However, most of these methods are not yet sufficiently mature to use with confidence in clinical trials, although rapid advances in the field suggest that reliable quantification of SVD lesion burden, tissue microstructural integrity and vascular dysfunction are imminent.
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Affiliation(s)
- Gordon W Blair
- Brain Research Imaging Centres, Centre for Clinical Brain Sciences, University of Edinburgh, 49 Little France Crescent, Chancellor's Building, Edinburgh, EH16 4SB, UK
| | - Maria Valdez Hernandez
- Brain Research Imaging Centres, Centre for Clinical Brain Sciences, University of Edinburgh, 49 Little France Crescent, Chancellor's Building, Edinburgh, EH16 4SB, UK
| | - Michael J Thrippleton
- Brain Research Imaging Centres, Centre for Clinical Brain Sciences, University of Edinburgh, 49 Little France Crescent, Chancellor's Building, Edinburgh, EH16 4SB, UK
| | - Fergus N Doubal
- Brain Research Imaging Centres, Centre for Clinical Brain Sciences, University of Edinburgh, 49 Little France Crescent, Chancellor's Building, Edinburgh, EH16 4SB, UK
| | - Joanna M Wardlaw
- Brain Research Imaging Centres, Centre for Clinical Brain Sciences, University of Edinburgh, 49 Little France Crescent, Chancellor's Building, Edinburgh, EH16 4SB, UK.
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107
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Planton M, Saint-Aubert L, Raposo N, Branchu L, Lyoubi A, Bonneville F, Albucher JF, Olivot JM, Péran P, Pariente J. High prevalence of cognitive impairment after intracerebral hemorrhage. PLoS One 2017; 12:e0178886. [PMID: 28570698 PMCID: PMC5453588 DOI: 10.1371/journal.pone.0178886] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 05/19/2017] [Indexed: 12/31/2022] Open
Abstract
Background Cognitive impairment seems to be frequent in intracerebral hemorrhage (ICH) survivors, but remains widely understudied. In this study, we investigated the frequency and patterns of vascular cognitive disorders (VCDs) in patients with cerebral amyloid angiopathy (CAA)-related and deep ICH compared to patients with mild cognitive impairment due to Alzheimer’s disease (MCI-AD) and healthy controls. Methods We prospectively recruited 20 patients with CAA-related lobar ICH, 20 with deep ICH, 20 with MCI-AD and 17 healthy controls. Patients with cognitive decline pre-ICH were excluded from the analysis. Each participant underwent a comprehensive neuropsychological assessment and a structural brain MRI. Cognitive assessment was performed at a median delay of 4 months after the acute phase in ICH patients, and more than 6 months after the first complaint in MCI-AD patients. Cognitive profiles were compared between groups. The prevalence of VCDs in the ICH groups was estimated using the recent VASCOG criteria. Results “Mild” and “major VCDs” were respectively observed in 87.5% and 2.5% of all ICH patients. Every patient in the CAA group had mild VCDs. No significant difference was observed in cognitive functioning between CAA-related and deep ICH patients. The most impaired process in the CAA group was naming, with a mean (±standard deviation) z-score of -5.2 ±5.5, followed by processing speed (-4.1±3.3), executive functioning (-2.6 ±2.5), memory (-2.4 ±3.5) and attention (-0.9 ±1.3). This cognitive pattern was different from the MCI-AD patients, but the groups were only different in gestural praxis, and by construction, in memory processes. Conclusions VCDs are frequent after ICH. Cognitive patterns of patients with deep or CAA-related ICH did not differ, but there was impaired performance in specific domains distinct from the effects of Alzheimer’s disease. Clinical trial registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT01619709.
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Affiliation(s)
- Mélanie Planton
- Department of Neurology, Toulouse University Hospital, Toulouse, France
- Toulouse NeuroImaging Center, Université de Toulouse, Inserm, UPS, France
- * E-mail:
| | - Laure Saint-Aubert
- Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Division of Translational Alzheimer Neurobiology, Karolinska Institutet, Stockholm, Sweden
| | - Nicolas Raposo
- Department of Neurology, Toulouse University Hospital, Toulouse, France
- Toulouse NeuroImaging Center, Université de Toulouse, Inserm, UPS, France
| | - Laura Branchu
- Toulouse NeuroImaging Center, Université de Toulouse, Inserm, UPS, France
| | - Aicha Lyoubi
- Department of Neurology, Groupe Hospitalier Lariboisière-Fernand-Widal, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Fabrice Bonneville
- Toulouse NeuroImaging Center, Université de Toulouse, Inserm, UPS, France
- Department of Neuroradiology, Toulouse University Hospital, Toulouse, France
| | - Jean-François Albucher
- Department of Neurology, Toulouse University Hospital, Toulouse, France
- Toulouse NeuroImaging Center, Université de Toulouse, Inserm, UPS, France
| | - Jean-Marc Olivot
- Department of Neurology, Toulouse University Hospital, Toulouse, France
- Toulouse NeuroImaging Center, Université de Toulouse, Inserm, UPS, France
| | - Patrice Péran
- Toulouse NeuroImaging Center, Université de Toulouse, Inserm, UPS, France
| | - Jérémie Pariente
- Department of Neurology, Toulouse University Hospital, Toulouse, France
- Toulouse NeuroImaging Center, Université de Toulouse, Inserm, UPS, France
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108
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Brain Structural Networks Associated with Intelligence and Visuomotor Ability. Sci Rep 2017; 7:2177. [PMID: 28526888 PMCID: PMC5438383 DOI: 10.1038/s41598-017-02304-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Accepted: 04/07/2017] [Indexed: 02/05/2023] Open
Abstract
Increasing evidence indicates that multiple structures in the brain are associated with intelligence and cognitive function at the network level. The association between the grey matter (GM) structural network and intelligence and cognition is not well understood. We applied a multivariate approach to identify the pattern of GM and link the structural network to intelligence and cognitive functions. Structural magnetic resonance imaging was acquired from 92 healthy individuals. Source-based morphometry analysis was applied to the imaging data to extract GM structural covariance. We assessed the intelligence, verbal fluency, processing speed, and executive functioning of the participants and further investigated the correlations of the GM structural networks with intelligence and cognitive functions. Six GM structural networks were identified. The cerebello-parietal component and the frontal component were significantly associated with intelligence. The parietal and frontal regions were each distinctively associated with intelligence by maintaining structural networks with the cerebellum and the temporal region, respectively. The cerebellar component was associated with visuomotor ability. Our results support the parieto-frontal integration theory of intelligence by demonstrating how each core region for intelligence works in concert with other regions. In addition, we revealed how the cerebellum is associated with intelligence and cognitive functions.
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109
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Farid K, Charidimou A, Baron JC. Amyloid positron emission tomography in sporadic cerebral amyloid angiopathy: A systematic critical update. NEUROIMAGE-CLINICAL 2017; 15:247-263. [PMID: 28560150 PMCID: PMC5435601 DOI: 10.1016/j.nicl.2017.05.002] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 05/02/2017] [Accepted: 05/04/2017] [Indexed: 01/07/2023]
Abstract
Sporadic cerebral amyloid angiopathy (CAA) is a very common small vessel disease of the brain, showing preferential and progressive amyloid-βdeposition in the wall of small arterioles and capillaries of the leptomeninges and cerebral cortex. CAA now encompasses not only a specific cerebrovascular pathological trait, but also different clinical syndromes - including spontaneous lobar intracerebral haemorrhage (ICH), dementia and ‘amyloid spells’ - an expanding spectrum of brain parenchymal MRI lesions and a set of diagnostic criteria – the Boston criteria, which have resulted in increasingly detecting CAA during life. Although currently available validated diagnostic criteria perform well in multiple lobar ICH, a formal diagnosis is currently lacking unless a brain biopsy is performed. This is partly because in practice CAA MRI biomarkers provide only indirect evidence for the disease. An accurate diagnosis of CAA in different clinical settings would have substantial impact for ICH risk stratification and antithrombotic drug use in elderly people, but also for sample homogeneity in drug trials. It has recently been demonstrated that vascular (in addition to parenchymal) amyloid-βdeposition can be detected and quantified in vivo by positron emission tomography (PET) amyloid tracers. This non-invasive approach has the potential to provide a molecular signature of CAA, and could in turn have major clinical impact. However, several issues around amyloid-PET in CAA remain unsettled and hence its diagnostic utility is limited. In this article we systematically review and critically appraise the published literature on amyloid-PET (PiB and other tracers) in sporadic CAA. We focus on two key areas: (a) the diagnostic utility of amyloid-PET in CAA and (b) the use of amyloid-PET as a window to understand pathophysiological mechanism of the disease. Key issues around amyloid-PET imaging in CAA, including relevant technical aspects are also covered in depth. A total of six small-scale studies have addressed (or reported data useful to address) the diagnostic utility of late-phase amyloid PET imaging in CAA, and one additional study dealt with early PiB images as a proxy of brain perfusion. Across these studies, amyloid PET imaging has definite diagnostic utility (currently tested only in probable CAA): it helps rule out CAA if negative, whether compared to healthy controls or to hypertensive deep ICH controls. If positive, however, differentiation from underlying incipient Alzheimer's disease (AD) can be challenging and so far, no approach (regional values, ratios, visual assessment) seems sufficient and specific enough, although early PiB data seem to hold promise. Based on the available evidence reviewed, we suggest a tentative diagnostic flow algorithm for amyloid-PET use in the clinical setting of suspected CAA, combining early- and late-phase PiB-PET images. We also identified ten mechanistic amyloid-PET studies providing early but promising proof-of-concept data on CAA pathophysiology and its various manifestations including key MRI lesions, cognitive impairment and large scale brain alterations. Key open questions that should be addressed in future studies of amyloid-PET imaging in CAA are identified and highlighted. CAA is a major cause of brain haemorrhage and cognitive impairment in aged subjects. Without brain biopsy, its current diagnosis largely relies on indirect MRI markers. Amyloid PET may provide a non-invasive molecular signature to formally diagnose CAA. Based on our review, amyloid PET has excellent sensitivity but specificity is unclear. Amyloid PET is also useful to investigate mechanisms underlying CAA manifestations.
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Affiliation(s)
- Karim Farid
- Department of Nuclear Medicine, Martinique University Hospital, Fort-de-France, Martinique
| | - Andreas Charidimou
- Massachusetts General Hospital, Department of Neurology, Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Jean-Claude Baron
- U894, Centre Hospitalier Sainte Anne, Sorbonne Paris Cité, Paris, France.
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110
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Dichgans M, Leys D. Vascular Cognitive Impairment. Circ Res 2017; 120:573-591. [PMID: 28154105 DOI: 10.1161/circresaha.116.308426] [Citation(s) in RCA: 308] [Impact Index Per Article: 44.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 07/28/2016] [Accepted: 08/29/2016] [Indexed: 01/10/2023]
Abstract
Cerebrovascular disease typically manifests with stroke, cognitive impairment, or both. Vascular cognitive impairment refers to all forms of cognitive disorder associated with cerebrovascular disease, regardless of the specific mechanisms involved. It encompasses the full range of cognitive deficits from mild cognitive impairment to dementia. In principle, any of the multiple causes of clinical stroke can cause vascular cognitive impairment. Recent work further highlights a role of microinfarcts, microhemorrhages, strategic white matter tracts, loss of microstructural tissue integrity, and secondary neurodegeneration. Vascular brain injury results in loss of structural and functional connectivity and, hence, compromise of functional networks within the brain. Vascular cognitive impairment is common both after stroke and in stroke-free individuals presenting to dementia clinics, and vascular pathology frequently coexists with neurodegenerative pathology, resulting in mixed forms of mild cognitive impairment or dementia. Vascular dementia is now recognized as the second most common form of dementia after Alzheimer's disease, and there is increasing awareness that targeting vascular risk may help to prevent dementia, even of the Alzheimer type. Recent advances in neuroimaging, neuropathology, epidemiology, and genetics have led to a deeper understanding of how vascular disease affects cognition. These new findings provide an opportunity for the present reappraisal of vascular cognitive impairment. We further briefly address current therapeutic concepts.
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Affiliation(s)
- Martin Dichgans
- From the Institute for Stroke and Dementia Research, Klinikum der Universität München, Ludwig-Maximilians-Universität LMU, Munich, Germany (M.D.); German Center for Neurodegenerative Diseases (DZNE), Munich, Germany (M.D.); Munich Cluster for Systems Neurology (SyNergy), Germany (M.D.); and University of Lille, INSERM, CHU Lille, U1171-Degenerative & Vascular Cognitive Disorders, F-59000 Lille, France (D.L.).
| | - Didier Leys
- From the Institute for Stroke and Dementia Research, Klinikum der Universität München, Ludwig-Maximilians-Universität LMU, Munich, Germany (M.D.); German Center for Neurodegenerative Diseases (DZNE), Munich, Germany (M.D.); Munich Cluster for Systems Neurology (SyNergy), Germany (M.D.); and University of Lille, INSERM, CHU Lille, U1171-Degenerative & Vascular Cognitive Disorders, F-59000 Lille, France (D.L.)
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111
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Reijmer YD, Fotiadis P, Charidimou A, van Veluw SJ, Xiong L, Riley GA, Martinez-Ramirez S, Schwab K, Viswanathan A, Gurol ME, Greenberg SM. Relationship between white matter connectivity loss and cortical thinning in cerebral amyloid angiopathy. Hum Brain Mapp 2017; 38:3723-3731. [PMID: 28462514 DOI: 10.1002/hbm.23629] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 03/08/2017] [Accepted: 04/17/2017] [Indexed: 02/07/2023] Open
Abstract
Patients with cerebral amyloid angiopathy (CAA) show loss of white matter connectivity and cortical thinning on MRI, primarily in posterior brain regions. Here we examined whether a potential causal relationship exists between these markers of subcortical and cortical brain injury by examining whether changes in cortical thickness progress in tandem with changes in their underlying connections. Thirty-one patients with probable CAA with brain MRI at two time points were included (follow-up time: 1.3 ± 0.4 years). Brain networks were reconstructed using diffusion MRI-based fiber tractography. Of each network node, we calculated the change in fractional anisotropy-weighted connectivity strength over time and the change in cortical thickness. The association between change in connectivity strength and cortical thickness was assessed with (hierarchical) linear regression models. Our results showed that decline in posterior network connectivity over time was strongly related to thinning of the occipital cortex (β = 0.65 (0.35-0.94), P < 0.001), but not to thinning of the other posterior or frontal cortices. However, at the level of individual network nodes, we found no association between connectivity strength and cortical thinning of the corresponding node (β = 0.009 ± 0.04, P = 0.80). Associations were independent of age, sex, and other brain MRI markers of CAA. To conclude, CAA patients with greater progressive loss of posterior white matter connectivity also have greater progression of occipital cortical thinning, but our results do not support a direct causal relationship between them. The association can be better explained by a shared underlying mechanism, which may form a potential target for future treatments. Hum Brain Mapp 38:3723-3731, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Yael D Reijmer
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts.,Department of Neurology, University Medical Center Utrecht, Brain Center Rudolf Magnus, Utrecht, The Netherlands
| | - Panagiotis Fotiadis
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Andreas Charidimou
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Susanne J van Veluw
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Li Xiong
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Grace A Riley
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Sergi Martinez-Ramirez
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Kristin Schwab
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Anand Viswanathan
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - M Edip Gurol
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Steven M Greenberg
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
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112
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Lyoubi-Idrissi AL, Jouvent E, Poupon C, Chabriat H. Diffusion magnetic resonance imaging in cerebral small vessel disease. Rev Neurol (Paris) 2017; 173:201-210. [PMID: 28392060 DOI: 10.1016/j.neurol.2017.03.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Revised: 12/04/2016] [Accepted: 03/09/2017] [Indexed: 01/13/2023]
Abstract
Cerebral small vessel disease (SVD) is frequent in the elderly, and accounts for a wide spectrum of clinical and radiological manifestations. This report summarizes the most important findings obtained using diffusion MRI (DWI) in SVD. With DWI and apparent diffusion coefficient (ADC) maps, recent ischemic lesions can easily be detected after acute stroke in SVD, while even multiple simultaneous lesions may be observed. Microstructural changes are frequent in SVD, with increases in diffusivity and decreases in anisotropy being the most reliable findings observed, mainly in white matter. These tissue changes are associated with clinical severity and especially executive dysfunction. They can also precede the usual MRI markers of SVD, such as white matter hyperintensities, microbleeds and lacunes. Thus, DWI may reveal surrogate markers of SVD progression and offer a better understanding of their underlying mechanisms.
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Affiliation(s)
- A L Lyoubi-Idrissi
- Department of Neurology, université de Paris Denis Didérot, DHU NeuroVasc Sorbonne Paris-Cité, GH Saint-Louis-Lariboisière, Assistance publique-Hôpitaux de Paris, Paris, France; CEA, Neurospin, 91191 Gif-sur-Yvette, France.
| | - E Jouvent
- Department of Neurology, université de Paris Denis Didérot, DHU NeuroVasc Sorbonne Paris-Cité, GH Saint-Louis-Lariboisière, Assistance publique-Hôpitaux de Paris, Paris, France; CEA, Neurospin, 91191 Gif-sur-Yvette, France; Inserm UMR 1161, faculté de médecine, Villemin, 75010 Paris, France
| | - C Poupon
- CEA, Neurospin, 91191 Gif-sur-Yvette, France
| | - H Chabriat
- Department of Neurology, université de Paris Denis Didérot, DHU NeuroVasc Sorbonne Paris-Cité, GH Saint-Louis-Lariboisière, Assistance publique-Hôpitaux de Paris, Paris, France; CEA, Neurospin, 91191 Gif-sur-Yvette, France; Inserm UMR 1161, faculté de médecine, Villemin, 75010 Paris, France
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113
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Saito S, Yamamoto Y, Maki T, Hattori Y, Ito H, Mizuno K, Harada-Shiba M, Kalaria RN, Fukushima M, Takahashi R, Ihara M. Taxifolin inhibits amyloid-β oligomer formation and fully restores vascular integrity and memory in cerebral amyloid angiopathy. Acta Neuropathol Commun 2017; 5:26. [PMID: 28376923 PMCID: PMC5379578 DOI: 10.1186/s40478-017-0429-5] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 03/22/2017] [Indexed: 01/31/2023] Open
Abstract
Cerebral amyloid angiopathy (CAA) induces various forms of cerebral infarcts and hemorrhages from vascular amyloid-β accumulation, resulting in acceleration of cognitive impairment, which is currently untreatable. Soluble amyloid-β protein likely impairs cerebrovascular integrity as well as cognitive function in early stage Alzheimer’s disease. Taxifolin, a flavonol with strong anti-oxidative and anti-glycation activities, has been reported to disassemble amyloid-β in vitro but the in vivo relevance remains unknown. Here, we investigated whether taxifolin has therapeutic potential in attenuating CAA, hypothesizing that inhibiting amyloid-β assembly may facilitate its clearance through several elimination pathways. Vehicle- or taxifolin-treated Tg-SwDI mice (commonly used to model CAA) were used in this investigation. Cognitive and cerebrovascular function, as well as the solubility and oligomerization of brain amyloid-β proteins, were investigated. Spatial reference memory was assessed by water maze test. Cerebral blood flow was measured with laser speckle flowmetry and cerebrovascular reactivity evaluated by monitoring cerebral blood flow changes in response to hypercapnia. Significantly reduced cerebrovascular pan-amyloid-β and amyloid-β1-40 accumulation was found in taxifolin-treated Tg-SwDI mice compared to vehicle-treated counterparts (n = 5). Spatial reference memory was severely impaired in vehicle-treated Tg-SwDI mice but normalized after taxifolin treatment, with scoring similar to wild type mice (n = 10–17). Furthermore, taxifolin completely restored decreased cerebral blood flow and cerebrovascular reactivity in Tg-SwDI mice (n = 4–6). An in vitro thioflavin-T assay showed taxifolin treatment resulted in efficient inhibition of amyloid-β1-40 assembly. In addition, a filter trap assay and ELISA showed Tg-SwDI mouse brain homogenates exhibited significantly reduced levels of amyloid-β oligomers in vivo after taxifolin treatment (n = 4–5), suggesting the effects of taxifolin on CAA are attributable to the inhibition of amyloid-β oligomer formation. In conclusion, taxifolin prevents amyloid-β oligomer assembly and fully sustains cognitive and cerebrovascular function in a CAA model mice. Taxifolin thus appears a promising therapeutic approach for CAA.
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114
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Valenti R, Charidimou A, Xiong L, Boulouis G, Fotiadis P, Ayres A, Riley G, Kuijf HJ, Reijmer YD, Pantoni L, Gurol ME, Davidsdottir S, Greenberg SM, Viswanathan A. Visuospatial Functioning in Cerebral Amyloid Angiopathy: A Pilot Study. J Alzheimers Dis 2017; 56:1223-1227. [DOI: 10.3233/jad-160927] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Raffaella Valenti
- Department of Neurology, Hemorrhagic Stroke Research Program, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
- Department of NEUROFARBA, Neuroscience Section, University of Florence, Florence, Italy
| | - Andreas Charidimou
- Department of Neurology, Hemorrhagic Stroke Research Program, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Li Xiong
- Department of Neurology, Hemorrhagic Stroke Research Program, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Gregoire Boulouis
- Department of Neurology, Hemorrhagic Stroke Research Program, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Panagiotis Fotiadis
- Department of Neurology, Hemorrhagic Stroke Research Program, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Alison Ayres
- Department of Neurology, Hemorrhagic Stroke Research Program, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Grace Riley
- Department of Neurology, Hemorrhagic Stroke Research Program, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Hugo J. Kuijf
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Yael D. Reijmer
- Department of Neurology, Hemorrhagic Stroke Research Program, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Leonardo Pantoni
- Department of NEUROFARBA, Neuroscience Section, University of Florence, Florence, Italy
| | - M. Edip Gurol
- Department of Neurology, Hemorrhagic Stroke Research Program, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Sigurros Davidsdottir
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Steven M. Greenberg
- Department of Neurology, Hemorrhagic Stroke Research Program, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Anand Viswanathan
- Department of Neurology, Hemorrhagic Stroke Research Program, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
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115
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Berlot R, O'Sullivan MJ. What can the topology of white matter structural networks tell us about mild cognitive impairment? FUTURE NEUROLOGY 2017. [DOI: 10.2217/fnl-2016-0022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The focus of investigation in cognitive disorders has shifted from single regional motifs toward brain networks. White matter connections collectively form the connectome, and provide the underpinnings of distributed patterns of brain activity. We examine findings about large-scale properties of structural networks in mild cognitive impairment (MCI), discuss these in terms of the mechanism of cognitive decline and evaluate potential clinical implications. Networks of patients with MCI exhibit reduced global efficiency, which associates with cognitive performance. The structural core of the connectome remains relatively unperturbed. Some global measures of network structure in MCI lie on a spectrum between healthy aging and Alzheimer's dementia. Connectomics seems ill-equipped to guide diagnosis, but provides measures suitable for monitoring disease progression and treatment effect.
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Affiliation(s)
- Rok Berlot
- Department of Basic & Clinical Neuroscience, Institute of Psychology, Psychiatry & Neuroscience, King's College London, 5 Cutcombe Road, London SE5 9RX, UK
- Department of Neurology, University Medical Centre Ljubljana, Zaloška 2, 1000 Ljubljana, Slovenia
| | - Michael J O'Sullivan
- Department of Basic & Clinical Neuroscience, Institute of Psychology, Psychiatry & Neuroscience, King's College London, 5 Cutcombe Road, London SE5 9RX, UK
- Mater Centre for Neuroscience & Queensland Brain Institute, University of Queensland, St Lucia QLD 4072, Brisbane, Australia
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116
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Xiong L, Davidsdottir S, Reijmer YD, Shoamanesh A, Roongpiboonsopit D, Thanprasertsuk S, Martinez-Ramirez S, Charidimou A, Ayres AM, Fotiadis P, Gurol E, Blacker DL, Greenberg SM, Viswanathan A. Cognitive Profile and its Association with Neuroimaging Markers of Non-Demented Cerebral Amyloid Angiopathy Patients in a Stroke Unit. J Alzheimers Dis 2017; 52:171-8. [PMID: 27060947 DOI: 10.3233/jad-150890] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND Cerebral amyloid angiopathy (CAA) is increasingly recognized as a cause of cognitive impairment in the elderly, but the cognitive profile in patients with the disease has not been well characterized. OBJECTIVE To characterize the neuropsychological profile of CAA patients without dementia and to determine the association between cognitive performance in different domains and neuroimaging lesions characteristic of CAA. METHODS Fifty-eight non-demented CAA patients were compared to 138 cognitively normal subjects using a standard neuropsychological test battery. Total brain volume (TBV), white matter hyperintensities, number of lobar cerebral microbleeds, hippocampal volume, and cortical superficial siderosis in all CAA patients were assessed. The association between these neuroimaging markers and neuropsychological performance in different cognitive domains in the CAA group were analyzed. RESULTS Patients with CAA had significantly worse performance on all individual neuropsychological domains tested, when compared to the cognitive normal group. The cognitive decline of CAA patients was most noticeable in tests for processing speed with a Z score of -1.92±1.56 (mean±SD), then followed by executive function (-0.93±1.01), episodic memory (-0.87±1.29), semantic fluency (-0.73±1.06), and attention (-0.42±0.98). TBV of the CAA patients was correlated with processing speed (β= 0.335, p = 0.03) and executive function (β= 0.394, p = 0.01). CONCLUSIONS Non-demented patients with CAA had cognitive deficits in multiple areas. Lower TBV was related to slower processing speed and worse executive function.
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Affiliation(s)
- Li Xiong
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.,Department of Neurology, Zhongnan Hospital, Wuhan University, Wuhan, China
| | - Sigurros Davidsdottir
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Yael D Reijmer
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Ashkan Shoamanesh
- Department of Neurology, McMaster University / Population Health Research Institute, Canada
| | - Duangnapa Roongpiboonsopit
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.,Department of Medicine, Naresuan University, Phitsanulok, Thailand
| | | | - Sergi Martinez-Ramirez
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Andreas Charidimou
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Alison M Ayres
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Panagiotis Fotiadis
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Edip Gurol
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Deborah L Blacker
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Steven M Greenberg
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Anand Viswanathan
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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117
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Berlot R, Metzler-Baddeley C, Ikram MA, Jones DK, O’Sullivan MJ. Global Efficiency of Structural Networks Mediates Cognitive Control in Mild Cognitive Impairment. Front Aging Neurosci 2016; 8:292. [PMID: 28018208 PMCID: PMC5157053 DOI: 10.3389/fnagi.2016.00292] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 11/21/2016] [Indexed: 11/21/2022] Open
Abstract
Background: Cognitive control has been linked to both the microstructure of individual tracts and the structure of whole-brain networks, but their relative contributions in health and disease remain unclear. Objective: To determine the contribution of both localized white matter tract damage and disruption of global network architecture to cognitive control, in older age and Mild Cognitive Impairment (MCI). Materials and Methods: Twenty-five patients with MCI and 20 age, sex, and intelligence-matched healthy volunteers were investigated with 3 Tesla structural magnetic resonance imaging (MRI). Cognitive control and episodic memory were evaluated with established tests. Structural network graphs were constructed from diffusion MRI-based whole-brain tractography. Their global measures were calculated using graph theory. Regression models utilized both global network metrics and microstructure of specific connections, known to be critical for each domain, to predict cognitive scores. Results: Global efficiency and the mean clustering coefficient of networks were reduced in MCI. Cognitive control was associated with global network topology. Episodic memory, in contrast, correlated with individual temporal tracts only. Relationships between cognitive control and network topology were attenuated by addition of single tract measures to regression models, consistent with a partial mediation effect. The mediation effect was stronger in MCI than healthy volunteers, explaining 23-36% of the effect of cingulum microstructure on cognitive control performance. Network clustering was a significant mediator in the relationship between tract microstructure and cognitive control in both groups. Conclusion: The status of critical connections and large-scale network topology are both important for maintenance of cognitive control in MCI. Mediation via large-scale networks is more important in patients with MCI than healthy volunteers. This effect is domain-specific, and true for cognitive control but not for episodic memory. Interventions to improve cognitive control will need to address both dysfunction of local circuitry and global network architecture to be maximally effective.
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Affiliation(s)
- Rok Berlot
- Division of Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King’s College LondonLondon, UK
- Department of Neurology, University Medical Centre LjubljanaLjubljana, Slovenia
| | - Claudia Metzler-Baddeley
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, and the Neuroscience and Mental Health Research Institute, Cardiff UniversityCardiff, UK
| | - M. Arfan Ikram
- Departments of Epidemiology, Radiology, Neurology, Erasmus MC, University Medical Center RotterdamRotterdam, Netherlands
| | - Derek K. Jones
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, and the Neuroscience and Mental Health Research Institute, Cardiff UniversityCardiff, UK
| | - Michael J. O’Sullivan
- Division of Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King’s College LondonLondon, UK
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, and the Neuroscience and Mental Health Research Institute, Cardiff UniversityCardiff, UK
- Mater Centre for Neuroscience and Queensland Brain Institute, University of QueenslandBrisbane, QLD, Australia
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118
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Tuladhar AM, Lawrence A, Norris DG, Barrick TR, Markus HS, de Leeuw F. Disruption of rich club organisation in cerebral small vessel disease. Hum Brain Mapp 2016; 38:1751-1766. [PMID: 27935154 PMCID: PMC6866838 DOI: 10.1002/hbm.23479] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 11/13/2016] [Accepted: 11/16/2016] [Indexed: 11/07/2022] Open
Abstract
Cerebral small vessel disease (SVD) is an important cause of vascular cognitive impairment. Recent studies have demonstrated that structural connectivity of brain networks in SVD is disrupted. However, little is known about the extent and location of the reduced connectivity in SVD. Here they investigate the rich club organisation-a set of highly connected and interconnected regions-and investigate whether there is preferential rich club disruption in SVD. Diffusion tensor imaging (DTI) and cognitive assessment were performed in a discovery sample of SVD patients (n = 115) and healthy control subjects (n = 50). Results were replicated in an independent dataset (49 SVD with confluent WMH cases and 108 SVD controls) with SVD patients having a similar SVD phenotype to that of the discovery cases. Rich club organisation was examined in structural networks derived from DTI followed by deterministic tractography. Structural networks in SVD patients were less dense with lower network strength and efficiency. Reduced connectivity was found in SVD, which was preferentially located in the connectivity between the rich club nodes rather than in the feeder and peripheral connections, a finding confirmed in both datasets. In discovery dataset, lower rich club connectivity was associated with lower scores on psychomotor speed (β = 0.29, P < 0.001) and executive functions (β = 0.20, P = 0.009). These results suggest that SVD is characterized by abnormal connectivity between rich club hubs in SVD and provide evidence that abnormal rich club organisation might contribute to the development of cognitive impairment in SVD. Hum Brain Mapp 38:1751-1766, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Anil M. Tuladhar
- Department of NeurologyRadboud University Medical Center, Donders Institute for Brain, Cognition and BehaviourNijmegenThe Netherlands
- Centre for Cognitive NeuroimagingRadboud University, Donders Institute for Brain, Cognition and BehaviourNijmegenThe Netherlands
| | - Andrew Lawrence
- Department of Clinical Neurosciences, Neurology UnitUniversity of CambridgeCambridgeUnited Kingdom
| | - David. G. Norris
- Centre for Cognitive NeuroimagingRadboud University, Donders Institute for Brain, Cognition and BehaviourNijmegenThe Netherlands
- Erwin L. Hahn Institute for Magnetic Resonance Imaging, University of Duisburg‐EssenArendahls Wiese 199, Tor 3EssenD‐45141Germany
- MIRA Institute for Biomedical Technology and Technical Medicine, University of TwenteEnschedeThe Netherlands
| | - Thomas R. Barrick
- St. George's University of London, Neuroscience Research Centre, Cardiovascular and Cell Sciences Research InstituteLondonUnited Kingdom
| | - Hugh S. Markus
- Department of Clinical Neurosciences, Neurology UnitUniversity of CambridgeCambridgeUnited Kingdom
| | - Frank‐Erik de Leeuw
- Department of NeurologyRadboud University Medical Center, Donders Institute for Brain, Cognition and BehaviourNijmegenThe Netherlands
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119
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Heiss WD, Rosenberg GA, Thiel A, Berlot R, de Reuck J. Neuroimaging in vascular cognitive impairment: a state-of-the-art review. BMC Med 2016; 14:174. [PMID: 27806705 PMCID: PMC5094143 DOI: 10.1186/s12916-016-0725-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Accepted: 10/25/2016] [Indexed: 01/07/2023] Open
Abstract
Imaging is critical in the diagnosis and treatment of dementia, particularly in vascular cognitive impairment, due to the visualization of ischemic and hemorrhagic injury of gray and white matter. Magnetic resonance imaging (MRI) and positron emission tomography (PET) provide structural and functional information. Clinical MRI is both generally available and versatile - T2-weighted images show infarcts, FLAIR shows white matter changes and lacunar infarcts, and susceptibility-weighted images reveal microbleeds. Diffusion MRI adds another dimension by showing graded damage to white matter, making it more sensitive to white matter injury than FLAIR. Regions of neuroinflammatory disruption of the blood-brain barrier with increased permeability can be quantified and visualized with dynamic contrast-enhanced MRI. PET shows metabolism of glucose and accumulation of amyloid and tau, which is useful in showing abnormal metabolism in Alzheimer's disease. Combining MRI and PET allows identification of patients with mixed dementia, with MRI showing white matter injury and PET demonstrating regional impairment of glucose metabolism and deposition of amyloid. Excellent anatomical detail can be observed with 7.0-Tesla MRI. Imaging is the optimal method to follow the effect of treatments since changes in MRI scans are seen prior to those in cognition. This review describes the role of various imaging modalities in the diagnosis and treatment of vascular cognitive impairment.
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Affiliation(s)
- Wolf-Dieter Heiss
- Max Planck Institute for Metabolism Research, Gleueler str. 50, D-50931, Cologne, Germany.
| | - Gary A Rosenberg
- Department of Neurology, UNM Memory and Aging Center, MSC 11 6035, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Alexander Thiel
- Department of Neurology & Neurosurgery, McGill University at SMBD Jewish General Hospital and Lady Davis Institute for Medical Research, Montreal, H3T 1E2, Québec, Canada
| | - Rok Berlot
- Department of Neurology (R.B.), University Medical Centre Ljubljana, 1000, Ljubljana, Slovenia
| | - Jacques de Reuck
- INSERM U1171, Degenerative and Vascular Cognitive Disorders, Université Lille 2, Lille, France
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120
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Dimond D, Ishaque A, Chenji S, Mah D, Chen Z, Seres P, Beaulieu C, Kalra S. White matter structural network abnormalities underlie executive dysfunction in amyotrophic lateral sclerosis. Hum Brain Mapp 2016; 38:1249-1268. [PMID: 27796080 DOI: 10.1002/hbm.23452] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 10/13/2016] [Accepted: 10/18/2016] [Indexed: 12/13/2022] Open
Abstract
Research in amyotrophic lateral sclerosis (ALS) suggests that executive dysfunction, a prevalent cognitive feature of the disease, is associated with abnormal structural connectivity and white matter integrity. In this exploratory study, we investigated the white matter constructs of executive dysfunction, and attempted to detect structural abnormalities specific to cognitively impaired ALS patients. Eighteen ALS patients and 22 age and education matched healthy controls underwent magnetic resonance imaging on a 4.7 Tesla scanner and completed neuropsychometric testing. ALS patients were categorized into ALS cognitively impaired (ALSci, n = 9) and ALS cognitively competent (ALScc, n = 5) groups. Tract-based spatial statistics and connectomics were used to compare white matter integrity and structural connectivity of ALSci and ALScc patients. Executive function performance was correlated with white matter FA and network metrics within the ALS group. Executive function performance in the ALS group correlated with global and local network properties, as well as FA, in regions throughout the brain, with a high predilection for the frontal lobe. ALSci patients displayed altered local connectivity and structural integrity in these same frontal regions that correlated with executive dysfunction. Our results suggest that executive dysfunction in ALS is related to frontal network disconnectivity, which potentially mediates domain-specific, or generalized cognitive impairment, depending on the degree of global network disruption. Furthermore, reported co-localization of decreased network connectivity and diminished white matter integrity suggests white matter pathology underlies this topological disruption. We conclude that executive dysfunction in ALSci is associated with frontal and global network disconnectivity, underlined by diminished white matter integrity. Hum Brain Mapp 38:1249-1268, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Dennis Dimond
- Neuroscience and Mental Health Institute, University of Alberta, 4-142 Katz Group Centre, 116 St. and 85 Ave, Edmonton, Alberta, T6G 2E1, Canada
| | - Abdullah Ishaque
- Neuroscience and Mental Health Institute, University of Alberta, 4-142 Katz Group Centre, 116 St. and 85 Ave, Edmonton, Alberta, T6G 2E1, Canada
| | - Sneha Chenji
- Neuroscience and Mental Health Institute, University of Alberta, 4-142 Katz Group Centre, 116 St. and 85 Ave, Edmonton, Alberta, T6G 2E1, Canada
| | - Dennell Mah
- Division of Neurology, Department of Medicine, University of Alberta, 7-132F Clinical Sciences Building, 11350-83 Ave, Edmonton, Alberta, T6G 2G3, Canada
| | - Zhang Chen
- Department of Biomedical Engineering, University of Alberta, 1098 Research Transition Facility, 8308-114 St, Edmonton, Alberta, T6G 2V2, Canada
| | - Peter Seres
- Department of Biomedical Engineering, University of Alberta, 1098 Research Transition Facility, 8308-114 St, Edmonton, Alberta, T6G 2V2, Canada
| | - Christian Beaulieu
- Neuroscience and Mental Health Institute, University of Alberta, 4-142 Katz Group Centre, 116 St. and 85 Ave, Edmonton, Alberta, T6G 2E1, Canada.,Department of Biomedical Engineering, University of Alberta, 1098 Research Transition Facility, 8308-114 St, Edmonton, Alberta, T6G 2V2, Canada
| | - Sanjay Kalra
- Neuroscience and Mental Health Institute, University of Alberta, 4-142 Katz Group Centre, 116 St. and 85 Ave, Edmonton, Alberta, T6G 2E1, Canada.,Division of Neurology, Department of Medicine, University of Alberta, 7-132F Clinical Sciences Building, 11350-83 Ave, Edmonton, Alberta, T6G 2G3, Canada.,Department of Biomedical Engineering, University of Alberta, 1098 Research Transition Facility, 8308-114 St, Edmonton, Alberta, T6G 2V2, Canada
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121
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Alfaro FJ, Lioutas VA, Pimentel DA, Chung CC, Bedoya F, Yoo WK, Novak V. Cognitive decline in metabolic syndrome is linked to microstructural white matter abnormalities. J Neurol 2016; 263:2505-2514. [PMID: 27730376 DOI: 10.1007/s00415-016-8292-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 09/19/2016] [Accepted: 09/20/2016] [Indexed: 01/21/2023]
Abstract
Subjects with metabolic syndrome (MetS) often show worse cognitive performance compared with the healthy population. We investigated whether microstructural white matter abnormalities are associated with cognitive performance in adults with MetS using diffusion tensor MR imaging. A total of 32 subjects with MetS (age 64.8 ± 7.8, 56.25 % female) and 23 age-, gender-, and education-matched healthy controls completed a battery of neuropsychological tests and diffusion tensor imaging (DTI) at 3-T MRI. Brain global and regional volumes, white matter fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (LD) were calculated. The least-square models adjusted for age, sex, HbA1c, hypertension, body mass index, hyperlipidemia, and white matter hyperintensities were used to evaluate the relationship between cognitive function and DTI. The MetS group had worse performance in verbal fluency (VF) and learning and memory function (total VF: T score (p = 0.01), VF: animals T score (p = 0.0001), Hopkins Verbal Learning Test (HVLT): Total recall T score (p = 0.0001), and HVLT: delayed recall T score (p = 0.002), as compared with controls. In the MetS group, abnormalities in diffusivity measures were associated with worse cognitive performance [VF: animals T score and left post-central gyrus-LD (p = 0.0007, r adj 0.4), R angular gyrus-RD (p = 0.0008, r adj 0.3), L supra-marginal gyrus-RD (p = 0.009, r adj 0.2) after adjusting for age, sex, HbA1c, 24 h mean BP, presence of hyperlipidemia, and global white matter hyperintensities]. Microstructural white matter abnormalities in the MetS group might be the underlying mechanisms of worse verbal learning and memory performance.
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Affiliation(s)
- Freddy J Alfaro
- Department of Neurology, Beth Israel Deaconess Medical Center, 185 Pilgrim Road, Palmer 127, Boston, MA, 02215, USA
| | - Vasileios-Arsenios Lioutas
- Department of Neurology, Beth Israel Deaconess Medical Center, 185 Pilgrim Road, Palmer 127, Boston, MA, 02215, USA
| | - Daniela A Pimentel
- Department of Neurology, Beth Israel Deaconess Medical Center, 185 Pilgrim Road, Palmer 127, Boston, MA, 02215, USA
| | - Chen-Chih Chung
- Department of Neurology, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan
| | - Francisco Bedoya
- Department of Neurology, Beth Israel Deaconess Medical Center, 185 Pilgrim Road, Palmer 127, Boston, MA, 02215, USA
| | - Woo-Kyoung Yoo
- Department of Physical Medicine and Rehabilitation, Hallym University College of Medicine, Chooncheon, Korea
- Hallym Institute of Translational Genomics and Bioinformatics, Hallym University Sacred Heart Hospital, Anyang, Korea
| | - Vera Novak
- Department of Neurology, Beth Israel Deaconess Medical Center, 185 Pilgrim Road, Palmer 127, Boston, MA, 02215, USA.
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Abstract
There is a paucity of accurate and reliable biomarkers to detect traumatic brain injury, grade its severity, and model post-traumatic brain injury (TBI) recovery. This gap could be addressed via advances in brain mapping which define injury signatures and enable tracking of post-injury trajectories at the individual level. Mapping of molecular and anatomical changes and of modifications in functional activation supports the conceptual paradigm of TBI as a disorder of large-scale neural connectivity. Imaging approaches with particular relevance are magnetic resonance techniques (diffusion weighted imaging, diffusion tensor imaging, susceptibility weighted imaging, magnetic resonance spectroscopy, functional magnetic resonance imaging, and positron emission tomographic methods including molecular neuroimaging). Inferences from mapping represent unique endophenotypes which have the potential to transform classification and treatment of patients with TBI. Limitations of these methods, as well as future research directions, are highlighted.
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The Influence of Vascular Risk Factors and Stroke on Cognition in Late Life: Analysis of the NACC Cohort. Alzheimer Dis Assoc Disord 2016; 29:287-93. [PMID: 25626633 DOI: 10.1097/wad.0000000000000080] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Vascular risk factors in mid-life predict late life cognitive decline in previously normal populations. We sought to investigate the contribution of vascular risk factors in late life to cognitive decline in a cohort of normal elderly individuals. METHODS Cognitively normal subjects were identified from the longitudinal cohort of participants in the National Alzheimer Coordinating Center (NACC) database (n=2975). The association between a composite score of vascular risk factors (based on the Framingham Stroke Risk Profile) and cognitive function was tested at baseline visit and estimated in longitudinal analyses using linear mixed-effects models. RESULTS Total vascular risk factor burden was associated with worse cognitive performance at baseline and faster decline longitudinally in univariate analyses but only with worse WAIS digit symbol performance in cross-sectional (estimate=-0.266 units/1 unit of Framingham Stroke Risk Profile Score; 95% confidence interval, -0.380 to -0.153; P<0.001) and longitudinal (estimate=-0.034 units/1 unit of Framingham Stroke Risk Profile Score/year; 95% confidence interval, -0.055 to -0.012; P=0.002) analyses after adjusting for age, education, and APOE genotype. Individuals with history of stroke performed significantly worse on the trails B, category fluency, and Boston naming tests in cross-sectional analyses and in delayed logical memory and digit span backwards in longitudinal analyses. CONCLUSIONS Although the modified Framingham Stroke Risk Profile in late-life predicts rate of decline on selective neurocognitive measures in previously normal elderly individuals, age appears to be the strongest risk factor for cognitive impairment in this population. History of stroke independently influences rate of cognitive decline in these individuals.
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Reijmer YD, Fotiadis P, Riley GA, Xiong L, Charidimou A, Boulouis G, Ayres AM, Schwab K, Rosand J, Gurol ME, Viswanathan A, Greenberg SM. Progression of Brain Network Alterations in Cerebral Amyloid Angiopathy. Stroke 2016; 47:2470-5. [PMID: 27576378 DOI: 10.1161/strokeaha.116.014337] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 07/18/2016] [Indexed: 12/19/2022]
Abstract
BACKGROUND AND PURPOSE We recently showed that cerebral amyloid angiopathy (CAA) is associated with functionally relevant brain network impairments, in particular affecting posterior white matter connections. Here we examined how these brain network impairments progress over time. METHODS Thirty-three patients with probable CAA underwent multimodal brain magnetic resonance imaging at 2 time points (mean follow-up time: 1.3±0.4 years). Brain networks of the hemisphere free of intracerebral hemorrhages were reconstructed using fiber tractography and graph theory. The global efficiency of the network and mean fractional anisotropies of posterior-posterior, frontal-frontal, and posterior-frontal network connections were calculated. Patients with moderate versus severe CAA were defined based on microbleed count, dichotomized at the median (median=35). RESULTS Global efficiency of the intracerebral hemorrhage-free hemispheric network declined from baseline to follow-up (-0.008±0.003; P=0.029). The decline in global efficiency was most pronounced for patients with severe CAA (group×time interaction P=0.03). The decline in global network efficiency was associated with worse executive functioning (β=0.46; P=0.03). Examination of subgroups of network connections revealed a decline in fractional anisotropies of posterior-posterior connections at both levels of CAA severity (-0.006±0.002; P=0.017; group×time interaction P=0.16). The fractional anisotropies of posterior-frontal and frontal-frontal connections declined in patients with severe but not moderate CAA (group×time interaction P=0.007 and P=0.005). Associations were independent of change in white matter hyperintensity volume. CONCLUSIONS Brain network impairment in patients with CAA worsens measurably over just 1.3-year follow-up and seem to progress from posterior to frontal connections with increasing disease severity.
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Affiliation(s)
- Yael D Reijmer
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston
| | - Panagiotis Fotiadis
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston
| | - Grace A Riley
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston
| | - Li Xiong
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston
| | - Andreas Charidimou
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston
| | - Gregoire Boulouis
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston
| | - Alison M Ayres
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston
| | - Kristin Schwab
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston
| | - Jonathan Rosand
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston
| | - M Edip Gurol
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston
| | - Anand Viswanathan
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston
| | - Steven M Greenberg
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston.
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Walker LC, Schelle J, Jucker M. The Prion-Like Properties of Amyloid-β Assemblies: Implications for Alzheimer's Disease. Cold Spring Harb Perspect Med 2016; 6:cshperspect.a024398. [PMID: 27270558 DOI: 10.1101/cshperspect.a024398] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Since the discovery that prion diseases can be transmitted to experimental animals by inoculation with afflicted brain matter, researchers have speculated that the brains of patients suffering from other neurodegenerative diseases might also harbor causative agents with transmissible properties. Foremost among these disorders is Alzheimer's disease (AD), the most common cause of dementia in the elderly. A growing body of research supports the concept that the pathogenesis of AD is initiated and sustained by the endogenous, seeded misfolding and aggregation of the protein fragment amyloid-β (Aβ). At the molecular level, this mechanism of nucleated protein self-assembly is virtually identical to that of prions consisting of the prion protein (PrP). The formation, propagation, and spread of Aβ seeds within the brain can thus be considered a fundamental feature of AD pathogenesis.
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Affiliation(s)
- Lary C Walker
- Yerkes National Primate Research Center and Department of Neurology, Emory University, Atlanta, Georgia 30322
| | - Juliane Schelle
- Department of Cellular Neurology, Hertie Institute for Clinical Brain Research, University of Tübingen, D-72076 Tübingen, Germany German Center for Neurodegenerative Diseases (DZNE), D-72076 Tübingen, Germany
| | - Mathias Jucker
- Department of Cellular Neurology, Hertie Institute for Clinical Brain Research, University of Tübingen, D-72076 Tübingen, Germany German Center for Neurodegenerative Diseases (DZNE), D-72076 Tübingen, Germany
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Case NF, Charlton A, Zwiers A, Batool S, McCreary CR, Hogan DB, Ismail Z, Zerna C, Coutts SB, Frayne R, Goodyear B, Haffenden A, Smith EE. Cerebral Amyloid Angiopathy Is Associated With Executive Dysfunction and Mild Cognitive Impairment. Stroke 2016; 47:2010-6. [PMID: 27338926 DOI: 10.1161/strokeaha.116.012999] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 05/17/2016] [Indexed: 01/14/2023]
Abstract
BACKGROUND AND PURPOSE Autopsy studies suggest that cerebral amyloid angiopathy (CAA) is associated with cognitive impairment and risk for dementia. We analyzed neuropsychological test data from a prospective cohort study of patients with CAA to identify the prevalence of cognitive impairment and its associations with brain magnetic resonance imaging features and the apolipoprotein E genotype. METHODS Data were analyzed from 34 CAA, 16 Alzheimer's disease, 69 mild cognitive impairment, and 27 ischemic stroke participants. Neuropsychological test results were expressed as z scores in relation to normative data provided by the test manuals and then grouped into domains of memory, executive function, and processing speed. RESULTS Mean test scores in CAA participants were significantly lower than norms for memory (-0.44±1.03; P=0.02), executive function (-1.14±1.07; P<0.001), and processing speed (-1.06±1.12; P<0.001). Twenty-seven CAA participants (79%) had mild cognitive impairment based on low cognitive performance accompanied by cognitive concerns. CAA participants had similarly low executive function scores as Alzheimer's disease, but relatively preserved memory. CAA participants' scores were lower than those of ischemic stroke controls for executive function and processing speed. Lower processing speed scores in CAA were associated with higher magnetic resonance imaging white matter hyperintensity volume. There were no associations with the apolipoprotein E ε4 allele. CONCLUSIONS Mild cognitive impairment is very prevalent in CAA. The overall cognitive profile of CAA is more similar to that seen in vascular cognitive impairment rather than Alzheimer's disease. White matter ischemic lesions may underlie some of the impaired processing speed in CAA.
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Affiliation(s)
- Nevicia F Case
- From the Department of Psychiatry, McGill University, Canada (N.F.C.); Department of Clinical Neurosciences, University of Calgary (A.C., A.Z., C.R.M., C.Z., R.F., B.G., A.H., E.E.S.), Department of Radiology (S.B., C.R.M., R.F., B.G.), Department of Medicine (D.B.H.), Hotchkiss Brain Institute (C.R.M., D.B.H., Z.I., S.B.C., R.F., B.G., E.E.S.), Department of Psychiatry (Z.I., S.B.C., E.E.S.), and Department of Community Health Sciences (S.B.C., E.E.S.), University of Calgary, Alberta, Canada; and Seaman Family MR Research Centre, Foothills Medical Centre, Alberta Health Services, Alberta, Canada (C.R.M., R.F., B.G.)
| | - Anna Charlton
- From the Department of Psychiatry, McGill University, Canada (N.F.C.); Department of Clinical Neurosciences, University of Calgary (A.C., A.Z., C.R.M., C.Z., R.F., B.G., A.H., E.E.S.), Department of Radiology (S.B., C.R.M., R.F., B.G.), Department of Medicine (D.B.H.), Hotchkiss Brain Institute (C.R.M., D.B.H., Z.I., S.B.C., R.F., B.G., E.E.S.), Department of Psychiatry (Z.I., S.B.C., E.E.S.), and Department of Community Health Sciences (S.B.C., E.E.S.), University of Calgary, Alberta, Canada; and Seaman Family MR Research Centre, Foothills Medical Centre, Alberta Health Services, Alberta, Canada (C.R.M., R.F., B.G.)
| | - Angela Zwiers
- From the Department of Psychiatry, McGill University, Canada (N.F.C.); Department of Clinical Neurosciences, University of Calgary (A.C., A.Z., C.R.M., C.Z., R.F., B.G., A.H., E.E.S.), Department of Radiology (S.B., C.R.M., R.F., B.G.), Department of Medicine (D.B.H.), Hotchkiss Brain Institute (C.R.M., D.B.H., Z.I., S.B.C., R.F., B.G., E.E.S.), Department of Psychiatry (Z.I., S.B.C., E.E.S.), and Department of Community Health Sciences (S.B.C., E.E.S.), University of Calgary, Alberta, Canada; and Seaman Family MR Research Centre, Foothills Medical Centre, Alberta Health Services, Alberta, Canada (C.R.M., R.F., B.G.)
| | - Saima Batool
- From the Department of Psychiatry, McGill University, Canada (N.F.C.); Department of Clinical Neurosciences, University of Calgary (A.C., A.Z., C.R.M., C.Z., R.F., B.G., A.H., E.E.S.), Department of Radiology (S.B., C.R.M., R.F., B.G.), Department of Medicine (D.B.H.), Hotchkiss Brain Institute (C.R.M., D.B.H., Z.I., S.B.C., R.F., B.G., E.E.S.), Department of Psychiatry (Z.I., S.B.C., E.E.S.), and Department of Community Health Sciences (S.B.C., E.E.S.), University of Calgary, Alberta, Canada; and Seaman Family MR Research Centre, Foothills Medical Centre, Alberta Health Services, Alberta, Canada (C.R.M., R.F., B.G.)
| | - Cheryl R McCreary
- From the Department of Psychiatry, McGill University, Canada (N.F.C.); Department of Clinical Neurosciences, University of Calgary (A.C., A.Z., C.R.M., C.Z., R.F., B.G., A.H., E.E.S.), Department of Radiology (S.B., C.R.M., R.F., B.G.), Department of Medicine (D.B.H.), Hotchkiss Brain Institute (C.R.M., D.B.H., Z.I., S.B.C., R.F., B.G., E.E.S.), Department of Psychiatry (Z.I., S.B.C., E.E.S.), and Department of Community Health Sciences (S.B.C., E.E.S.), University of Calgary, Alberta, Canada; and Seaman Family MR Research Centre, Foothills Medical Centre, Alberta Health Services, Alberta, Canada (C.R.M., R.F., B.G.)
| | - David B Hogan
- From the Department of Psychiatry, McGill University, Canada (N.F.C.); Department of Clinical Neurosciences, University of Calgary (A.C., A.Z., C.R.M., C.Z., R.F., B.G., A.H., E.E.S.), Department of Radiology (S.B., C.R.M., R.F., B.G.), Department of Medicine (D.B.H.), Hotchkiss Brain Institute (C.R.M., D.B.H., Z.I., S.B.C., R.F., B.G., E.E.S.), Department of Psychiatry (Z.I., S.B.C., E.E.S.), and Department of Community Health Sciences (S.B.C., E.E.S.), University of Calgary, Alberta, Canada; and Seaman Family MR Research Centre, Foothills Medical Centre, Alberta Health Services, Alberta, Canada (C.R.M., R.F., B.G.)
| | - Zahinoor Ismail
- From the Department of Psychiatry, McGill University, Canada (N.F.C.); Department of Clinical Neurosciences, University of Calgary (A.C., A.Z., C.R.M., C.Z., R.F., B.G., A.H., E.E.S.), Department of Radiology (S.B., C.R.M., R.F., B.G.), Department of Medicine (D.B.H.), Hotchkiss Brain Institute (C.R.M., D.B.H., Z.I., S.B.C., R.F., B.G., E.E.S.), Department of Psychiatry (Z.I., S.B.C., E.E.S.), and Department of Community Health Sciences (S.B.C., E.E.S.), University of Calgary, Alberta, Canada; and Seaman Family MR Research Centre, Foothills Medical Centre, Alberta Health Services, Alberta, Canada (C.R.M., R.F., B.G.)
| | - Charlotte Zerna
- From the Department of Psychiatry, McGill University, Canada (N.F.C.); Department of Clinical Neurosciences, University of Calgary (A.C., A.Z., C.R.M., C.Z., R.F., B.G., A.H., E.E.S.), Department of Radiology (S.B., C.R.M., R.F., B.G.), Department of Medicine (D.B.H.), Hotchkiss Brain Institute (C.R.M., D.B.H., Z.I., S.B.C., R.F., B.G., E.E.S.), Department of Psychiatry (Z.I., S.B.C., E.E.S.), and Department of Community Health Sciences (S.B.C., E.E.S.), University of Calgary, Alberta, Canada; and Seaman Family MR Research Centre, Foothills Medical Centre, Alberta Health Services, Alberta, Canada (C.R.M., R.F., B.G.)
| | - Shelagh B Coutts
- From the Department of Psychiatry, McGill University, Canada (N.F.C.); Department of Clinical Neurosciences, University of Calgary (A.C., A.Z., C.R.M., C.Z., R.F., B.G., A.H., E.E.S.), Department of Radiology (S.B., C.R.M., R.F., B.G.), Department of Medicine (D.B.H.), Hotchkiss Brain Institute (C.R.M., D.B.H., Z.I., S.B.C., R.F., B.G., E.E.S.), Department of Psychiatry (Z.I., S.B.C., E.E.S.), and Department of Community Health Sciences (S.B.C., E.E.S.), University of Calgary, Alberta, Canada; and Seaman Family MR Research Centre, Foothills Medical Centre, Alberta Health Services, Alberta, Canada (C.R.M., R.F., B.G.)
| | - Richard Frayne
- From the Department of Psychiatry, McGill University, Canada (N.F.C.); Department of Clinical Neurosciences, University of Calgary (A.C., A.Z., C.R.M., C.Z., R.F., B.G., A.H., E.E.S.), Department of Radiology (S.B., C.R.M., R.F., B.G.), Department of Medicine (D.B.H.), Hotchkiss Brain Institute (C.R.M., D.B.H., Z.I., S.B.C., R.F., B.G., E.E.S.), Department of Psychiatry (Z.I., S.B.C., E.E.S.), and Department of Community Health Sciences (S.B.C., E.E.S.), University of Calgary, Alberta, Canada; and Seaman Family MR Research Centre, Foothills Medical Centre, Alberta Health Services, Alberta, Canada (C.R.M., R.F., B.G.)
| | - Brad Goodyear
- From the Department of Psychiatry, McGill University, Canada (N.F.C.); Department of Clinical Neurosciences, University of Calgary (A.C., A.Z., C.R.M., C.Z., R.F., B.G., A.H., E.E.S.), Department of Radiology (S.B., C.R.M., R.F., B.G.), Department of Medicine (D.B.H.), Hotchkiss Brain Institute (C.R.M., D.B.H., Z.I., S.B.C., R.F., B.G., E.E.S.), Department of Psychiatry (Z.I., S.B.C., E.E.S.), and Department of Community Health Sciences (S.B.C., E.E.S.), University of Calgary, Alberta, Canada; and Seaman Family MR Research Centre, Foothills Medical Centre, Alberta Health Services, Alberta, Canada (C.R.M., R.F., B.G.)
| | - Angela Haffenden
- From the Department of Psychiatry, McGill University, Canada (N.F.C.); Department of Clinical Neurosciences, University of Calgary (A.C., A.Z., C.R.M., C.Z., R.F., B.G., A.H., E.E.S.), Department of Radiology (S.B., C.R.M., R.F., B.G.), Department of Medicine (D.B.H.), Hotchkiss Brain Institute (C.R.M., D.B.H., Z.I., S.B.C., R.F., B.G., E.E.S.), Department of Psychiatry (Z.I., S.B.C., E.E.S.), and Department of Community Health Sciences (S.B.C., E.E.S.), University of Calgary, Alberta, Canada; and Seaman Family MR Research Centre, Foothills Medical Centre, Alberta Health Services, Alberta, Canada (C.R.M., R.F., B.G.)
| | - Eric E Smith
- From the Department of Psychiatry, McGill University, Canada (N.F.C.); Department of Clinical Neurosciences, University of Calgary (A.C., A.Z., C.R.M., C.Z., R.F., B.G., A.H., E.E.S.), Department of Radiology (S.B., C.R.M., R.F., B.G.), Department of Medicine (D.B.H.), Hotchkiss Brain Institute (C.R.M., D.B.H., Z.I., S.B.C., R.F., B.G., E.E.S.), Department of Psychiatry (Z.I., S.B.C., E.E.S.), and Department of Community Health Sciences (S.B.C., E.E.S.), University of Calgary, Alberta, Canada; and Seaman Family MR Research Centre, Foothills Medical Centre, Alberta Health Services, Alberta, Canada (C.R.M., R.F., B.G.).
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Pasi M, van Uden IWM, Tuladhar AM, de Leeuw FE, Pantoni L. White Matter Microstructural Damage on Diffusion Tensor Imaging in Cerebral Small Vessel Disease: Clinical Consequences. Stroke 2016; 47:1679-84. [PMID: 27103015 DOI: 10.1161/strokeaha.115.012065] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Accepted: 03/22/2016] [Indexed: 11/16/2022]
Affiliation(s)
- Marco Pasi
- From the NEUROFARBA Department, Neuroscience Section, University of Florence, Florence, Italy (M.P., L.P.); and Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands (I.W.M.v.U., A.M.T., F.-E.d.L.)
| | - Inge W M van Uden
- From the NEUROFARBA Department, Neuroscience Section, University of Florence, Florence, Italy (M.P., L.P.); and Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands (I.W.M.v.U., A.M.T., F.-E.d.L.)
| | - Anil M Tuladhar
- From the NEUROFARBA Department, Neuroscience Section, University of Florence, Florence, Italy (M.P., L.P.); and Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands (I.W.M.v.U., A.M.T., F.-E.d.L.)
| | - Frank-Erik de Leeuw
- From the NEUROFARBA Department, Neuroscience Section, University of Florence, Florence, Italy (M.P., L.P.); and Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands (I.W.M.v.U., A.M.T., F.-E.d.L.)
| | - Leonardo Pantoni
- From the NEUROFARBA Department, Neuroscience Section, University of Florence, Florence, Italy (M.P., L.P.); and Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands (I.W.M.v.U., A.M.T., F.-E.d.L.).
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Zha Z, Song J, Choi SR, Wu Z, Ploessl K, Smith M, Kung H. 68Ga-Bivalent Polypegylated Styrylpyridine Conjugates for Imaging Aβ Plaques in Cerebral Amyloid Angiopathy. Bioconjug Chem 2016; 27:1314-23. [DOI: 10.1021/acs.bioconjchem.6b00127] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Zhihao Zha
- Beijing
Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China
- Department
of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Jin Song
- Beijing
Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China
- Department
of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Seok Rye Choi
- Five Eleven Pharma Inc., Philadelphia, Pennsylvania 19104, United States
- Department
of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Zehui Wu
- Beijing
Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China
- Department
of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Karl Ploessl
- Five Eleven Pharma Inc., Philadelphia, Pennsylvania 19104, United States
- Department
of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Megan Smith
- Five Eleven Pharma Inc., Philadelphia, Pennsylvania 19104, United States
| | - Hank Kung
- Beijing
Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China
- Five Eleven Pharma Inc., Philadelphia, Pennsylvania 19104, United States
- Department
of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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Wilson D, Jäger HR, Werring DJ. Anticoagulation for Atrial Fibrillation in Patients with Cerebral Microbleeds. Curr Atheroscler Rep 2016; 17:47. [PMID: 26093663 DOI: 10.1007/s11883-015-0524-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Intracranial haemorrhage (ICH) is the most feared and devastating complication of oral anticoagulation, with high mortality and disability in survivors. Oral anticoagulant-related ICH is increasing in incidence, most likely in part due to the increased use of anticoagulation for atrial fibrillation in the elderly populations with a high prevalence of bleeding-prone cerebral small vessel diseases. Risk scores have been developed to predict bleeding, including ICH, as well as the risk of ischaemic stroke. Recently, attention has turned to brain imaging, in particular, MRI detection of potential prognostic biomarkers, which may help better predict outcomes and individualize anticoagulant decisions. Cerebral microbleeds (CMBs)--small, round areas of signal loss on blood-sensitive MR sequences--have been hypothesized to be a marker for bleeding-prone small vessel pathology, and thus, future symptomatic ICH risk. In this review, we outline the prevalence and prognostic value of CMBs in populations affected by AF for whom anticoagulation decisions are relevant, including healthy older individuals and survivors of ischaemic stroke or ICH. We consider the limitations of currently available evidence, and discuss future research directions in relation to both prognostic markers and treatment options for atrial fibrillation.
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Affiliation(s)
- Duncan Wilson
- Stroke Research Group, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK
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Kennis M, van Rooij SJH, Kahn RS, Geuze E, Leemans A. Choosing the polarity of the phase-encoding direction in diffusion MRI: Does it matter for group analysis? Neuroimage Clin 2016; 11:539-547. [PMID: 27158586 PMCID: PMC4845159 DOI: 10.1016/j.nicl.2016.03.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 03/10/2016] [Accepted: 03/31/2016] [Indexed: 12/04/2022]
Abstract
Notorious for degrading diffusion MRI data quality are so-called susceptibility-induced off-resonance fields, which cause non-linear geometric image deformations. While acquiring additional data to correct for these distortions alleviates the adverse effects of this artifact drastically - e.g., by reversing the polarity of the phase-encoding (PE) direction - this strategy is often not an option due to scan time constraints. Especially in a clinical context, where patient comfort and safety are of paramount importance, acquisition specifications are preferred that minimize scan time, typically resulting in data obtained with only one PE direction. In this work, we investigated whether choosing a different polarity of the PE direction would affect the outcome of a specific clinical research study. To address this methodological question, fractional anisotropy (FA) estimates of FreeSurfer brain regions were obtained in civilian and combat controls, remitted posttraumatic stress disorder (PTSD) patients, and persistent PTSD patients before and after trauma-focused therapy and were compared between diffusion MRI data sets acquired with different polarities of the PE direction (posterior-to-anterior, PA and anterior-to-posterior, AP). Our results demonstrate that regional FA estimates differ on average in the order of 5% between AP and PA PE data. In addition, when comparing FA estimates between different subject groups for specific cingulum subdivisions, the conclusions for AP and PA PE data were not in agreement. These findings increase our understanding of how one of the most pronounced data artifacts in diffusion MRI can impact group analyses and should encourage users to be more cautious when interpreting and reporting study outcomes derived from data acquired along a single PE direction.
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Affiliation(s)
- M Kennis
- Brain Center Rudolf Magnus, Department of Psychiatry, University Medical Center Utrecht, Utrecht, The Netherlands; Research Center, Military Mental Healthcare, Ministry of Defence, Utrecht, The Netherlands.
| | - S J H van Rooij
- Brain Center Rudolf Magnus, Department of Psychiatry, University Medical Center Utrecht, Utrecht, The Netherlands; Research Center, Military Mental Healthcare, Ministry of Defence, Utrecht, The Netherlands; Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - R S Kahn
- Brain Center Rudolf Magnus, Department of Psychiatry, University Medical Center Utrecht, Utrecht, The Netherlands
| | - E Geuze
- Brain Center Rudolf Magnus, Department of Psychiatry, University Medical Center Utrecht, Utrecht, The Netherlands; Research Center, Military Mental Healthcare, Ministry of Defence, Utrecht, The Netherlands
| | - A Leemans
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
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131
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Reijmer YD, Fotiadis P, Piantoni G, Boulouis G, Kelly KE, Gurol ME, Leemans A, O'Sullivan MJ, Greenberg SM, Viswanathan A. Small vessel disease and cognitive impairment: The relevance of central network connections. Hum Brain Mapp 2016; 37:2446-54. [PMID: 27004840 DOI: 10.1002/hbm.23186] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Revised: 03/02/2016] [Accepted: 03/08/2016] [Indexed: 12/11/2022] Open
Abstract
Central brain network connections greatly contribute to overall network efficiency. Here we examined whether small vessel disease (SVD) related white matter alterations in central brain network connections have a greater impact on executive functioning than alterations in non-central brain network connections. Brain networks were reconstructed from diffusion-weighted MRI scans in 72 individuals (75 ± 8 years) with cognitive impairment and SVD on MRI. The centrality of white matter connections in the network was defined using graph theory. The association between the fractional anisotropy (FA) of central versus non-central connections, executive functioning, and markers of SVD was evaluated with linear regression and mediation analysis. Lower FA in central network connections was more strongly associated with impairment in executive functioning than FA in non-central network connections (r = 0.41 vs. r = 0.27; P < 0.05). Results were consistent across varying thresholds to define the central subnetwork (>50%-10% connections). Higher SVD burden was associated with lower FA in central as well as non-central network connections. However, only central network FA mediated the relationship between white matter hyperintensity volume and executive functioning [change in regression coefficient after mediation (95% CI): -0.15 (-0.35 to -0.02)]. The mediation effect was not observed for FA alterations in non-central network connections [-0.03 (-0.19 to 0.04)]. These findings suggest that the centrality of network connections, and thus their contribution to global network efficiency, appears to be relevant for understanding the relationship between SVD and cognitive impairment. Hum Brain Mapp 37:2446-2454, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Yael D Reijmer
- Hemorrhagic Stroke Research Program, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Panagiotis Fotiadis
- Hemorrhagic Stroke Research Program, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Giovanni Piantoni
- Department of Neurology, Cortical physiology laboratory, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Gregoire Boulouis
- Hemorrhagic Stroke Research Program, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Kathleen E Kelly
- Athinoula a. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, Massachusetts
| | - Mahmut E Gurol
- Hemorrhagic Stroke Research Program, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Alexander Leemans
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Michael J O'Sullivan
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology & Neuroscience, King's College London, United Kingdom
| | - Steven M Greenberg
- Hemorrhagic Stroke Research Program, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Anand Viswanathan
- Hemorrhagic Stroke Research Program, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
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Abstract
PURPOSE OF REVIEW Epidemiological investigations have proposed strict control of vascular risk factors as a strategy to overcome dementia, because of the close interaction between cerebrovascular disease (CVD) and Alzheimer's disease. In light of recent advances in basic, translational, and clinical research in the area, this review focuses on the significance of CVD in Alzheimer's disease pathogenesis. RECENT FINDINGS Alzheimer's disease and CVD share several risk factors, and the coexistence of both pathologies is frequently noted. CVD and subsequent cerebral blood flow reduction would increase amyloid β (Aβ) production by modulating β and γ-secretase. Furthermore, CVD impairs Aβ clearance, which is mainly driven by vascular mediated systems, including active transport across the blood-brain barrier, and perivascular lymphatic/paravascular glymphatic drainage systems. Thus, CVD may disturb homeostasis between Aβ production and clearance, thereby aggravating Alzheimer's disease. Recent translational researches in this field aim to facilitate Aβ clearance. Several candidate drugs are being tested in clinical trials. SUMMARY Compared with Aβ pathology, little is known about the relationship between tau pathology and CVD, although some studies have shown that CVD has an influence on tau pathology. The close interrelationship between Alzheimer's disease and CVD suggests the necessity of the maintenance of cerebrovascular integrity, which may herald a new generation of dementia treatment strategies.
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133
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Perrone D, Jeurissen B, Aelterman J, Roine T, Sijbers J, Pizurica A, Leemans A, Philips W. D-BRAIN: Anatomically Accurate Simulated Diffusion MRI Brain Data. PLoS One 2016; 11:e0149778. [PMID: 26930054 PMCID: PMC4773122 DOI: 10.1371/journal.pone.0149778] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 02/04/2016] [Indexed: 12/13/2022] Open
Abstract
Diffusion Weighted (DW) MRI allows for the non-invasive study of water diffusion inside living tissues. As such, it is useful for the investigation of human brain white matter (WM) connectivity in vivo through fiber tractography (FT) algorithms. Many DW-MRI tailored restoration techniques and FT algorithms have been developed. However, it is not clear how accurately these methods reproduce the WM bundle characteristics in real-world conditions, such as in the presence of noise, partial volume effect, and a limited spatial and angular resolution. The difficulty lies in the lack of a realistic brain phantom on the one hand, and a sufficiently accurate way of modeling the acquisition-related degradation on the other. This paper proposes a software phantom that approximates a human brain to a high degree of realism and that can incorporate complex brain-like structural features. We refer to it as a Diffusion BRAIN (D-BRAIN) phantom. Also, we propose an accurate model of a (DW) MRI acquisition protocol to allow for validation of methods in realistic conditions with data imperfections. The phantom model simulates anatomical and diffusion properties for multiple brain tissue components, and can serve as a ground-truth to evaluate FT algorithms, among others. The simulation of the acquisition process allows one to include noise, partial volume effects, and limited spatial and angular resolution in the images. In this way, the effect of image artifacts on, for instance, fiber tractography can be investigated with great detail. The proposed framework enables reliable and quantitative evaluation of DW-MR image processing and FT algorithms at the level of large-scale WM structures. The effect of noise levels and other data characteristics on cortico-cortical connectivity and tractography-based grey matter parcellation can be investigated as well.
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Affiliation(s)
- Daniele Perrone
- iMinds - IPI - TELIN, Ghent University, Ghent, Belgium
- * E-mail:
| | - Ben Jeurissen
- iMinds - Vision Lab, Department of Physics, University of Antwerp, Antwerp, Belgium
| | - Jan Aelterman
- iMinds - IPI - TELIN, Ghent University, Ghent, Belgium
| | - Timo Roine
- iMinds - Vision Lab, Department of Physics, University of Antwerp, Antwerp, Belgium
| | - Jan Sijbers
- iMinds - Vision Lab, Department of Physics, University of Antwerp, Antwerp, Belgium
| | | | - Alexander Leemans
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
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Gurol ME. Molecular Neuroimaging in Vascular Cognitive Impairment. Stroke 2016; 47:1146-52. [PMID: 26883497 DOI: 10.1161/strokeaha.115.007958] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 01/28/2016] [Indexed: 12/27/2022]
Affiliation(s)
- M Edip Gurol
- From the Department of Neurology, Massachusetts General Hospital, Boston.
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135
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Barone FC, Gustafson D, Crystal HA, Moreno H, Adamski MG, Arai K, Baird AE, Balucani C, Brickman AM, Cechetto D, Gorelick P, Biessels GJ, Kiliaan A, Launer L, Schneider J, Sorond FA, Whitmer R, Wright C, Zhang ZG. First translational 'Think Tank' on cerebrovascular disease, cognitive impairment and dementia. J Transl Med 2016; 14:50. [PMID: 26873444 PMCID: PMC4752794 DOI: 10.1186/s12967-016-0806-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2015] [Accepted: 01/22/2016] [Indexed: 01/12/2023] Open
Abstract
As the human population continues to age, an increasing number of people will exhibit significant deficits in cognitive function and dementia. It is now recognized that cerebrovascular, metabolic and neurodegenerative diseases all play major roles in the evolution of cognitive impairment and dementia. Thus with our more recent recognition of these relationships and our need to understand and more positively impact on this world health problem, "The Leo and Anne Albert Charitable Trust" (Gene Pranzo, Trustee with significant support from Susan Brogan, Meeting Planner) provided generous support for this inaugural international workshop that was held from April 13-16, 2015 at the beautiful Ritz Carlton Golf Resort in North Naples, Florida. Researchers from SUNY Downstate Medical Center, Brooklyn, NY organized the event by selecting the present group of translationally inclined preclinical, clinical and population scientists focused on cerebrovascular disease (CVD) risk and its progression to vascular cognitive impairment (VCI) and dementia. Participants at the workshop addressed important issues related to aging, cognition and dementia by: (1) sharing new data, information and perspectives that intersect vascular, metabolic and neurodegenerative diseases, (2) discussing gaps in translating population risk, clinical and preclinical information to the progression of cognitive loss, and (3) debating new approaches and methods to fill these gaps that can translate into future therapeutic interventions. Participants agreed on topics for group discussion prior to the meeting and focused on specific translational goals that included promoting better understanding of dementia mechanisms, the identification of potential therapeutic targets for intervention, and discussed/debated the potential utility of diagnostic/prognostic markers. Below summarizes the new data-presentations, concepts, novel directions and specific discussion topics addressed by this international translational team at our "First Leo and Anne Albert Charitable Trust 'Think Tank' VCI workshop".
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Affiliation(s)
- Frank C Barone
- Neurology, SUNY Downstate Medical Center, Brooklyn, NY, USA.
- Physiology and Pharmacology, SUNY Downstate Medical Center, Brooklyn, NY, USA.
| | - Deborah Gustafson
- Neurology, SUNY Downstate Medical Center, Brooklyn, NY, USA.
- Section Neuroepidemiology, SUNY Downstate Medical Center, Brooklyn, NY, USA.
| | - Howard A Crystal
- Neurology, SUNY Downstate Medical Center, Brooklyn, NY, USA.
- Pathology, SUNY Downstate Medical Center, Brooklyn, NY, USA.
| | - Herman Moreno
- Neurology, SUNY Downstate Medical Center, Brooklyn, NY, USA.
- Physiology and Pharmacology, SUNY Downstate Medical Center, Brooklyn, NY, USA.
| | - Mateusz G Adamski
- Jagiellonian Centre for Experimental Therapeutics, Jagiellonian University, Krakow, Poland.
| | - Ken Arai
- Neuroprotection Research Laboratory, Departments of Radiology and Neurology, Massachusetts General Hospital, Harvard Medical School, CharlesTown, Boston, MA, USA.
| | - Alison E Baird
- Neurology, SUNY Downstate Medical Center, Brooklyn, NY, USA.
- Physiology and Pharmacology, SUNY Downstate Medical Center, Brooklyn, NY, USA.
| | | | - Adam M Brickman
- Taub Institute for Alzheimer's Disease and the Aging Brain, Department of Neurology, Columbia University, New York, NY, USA.
| | - David Cechetto
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada.
| | - Philip Gorelick
- Translational Science and Molecular Medicine, Michigan State University College of Human Medicine, Mercy Health Hauenstein Neurosciences, Grand Rapids, MI, USA.
| | - Geert Jan Biessels
- Department of Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, The Netherlands.
| | - Amanda Kiliaan
- Department of Anatomy, Preclinical Imaging Center, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center Nijmegen, Nijmegen, The Netherlands.
| | - Lenore Launer
- Neuroepidemiology Section, Intramural Research Program, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA.
| | - Julie Schneider
- Pathology (Neuropathology) and Neurological Sciences, Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA.
| | - Farzaneh A Sorond
- Department of Neurology, Stroke Division, Brigham and Women's Hospital, Boston, MA, USA.
| | - Rachel Whitmer
- Division of Research, Kaiser Permanente Northern California, Oakland, CA, USA.
| | - Clinton Wright
- McKnight Brain Institute, Division of Cognitive Disorders, Neurology, Public Health Sciences and Neuroscience, University of Miami, Miami, FL, USA.
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Charidimou A, Boulouis G, Haley K, Auriel E, van Etten ES, Fotiadis P, Reijmer Y, Ayres A, Vashkevich A, Dipucchio ZY, Schwab KM, Martinez-Ramirez S, Rosand J, Viswanathan A, Greenberg SM, Gurol ME. White matter hyperintensity patterns in cerebral amyloid angiopathy and hypertensive arteriopathy. Neurology 2016; 86:505-11. [PMID: 26747886 PMCID: PMC4753727 DOI: 10.1212/wnl.0000000000002362] [Citation(s) in RCA: 148] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 10/12/2015] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To identify different white matter hyperintensity (WMH) patterns between 2 hemorrhage-prone cerebral small vessel diseases (SVD): cerebral amyloid angiopathy (CAA) and hypertensive arteriopathy (HA). METHODS Consecutive patients with SVD-related intracerebral hemorrhage (ICH) from a single-center prospective cohort were analyzed. Four predefined subcortical WMH patterns were compared between the CAA and HA groups. These WMH patterns were (1) multiple subcortical spots; (2) peri-basal ganglia (BG); (3) large posterior subcortical patches; and (4) anterior subcortical patches. Their associations with other imaging (cerebral microbleeds [CMBs], enlarged perivascular spaces [EPVS]) and clinical markers of SVD were investigated using multivariable logistic regression. RESULTS The cohort included 319 patients with CAA and 137 patients with HA. Multiple subcortical spots prevalence was higher in the CAA compared to the HA group (29.8% vs 16.8%; p = 0.004). Peri-BG WMH pattern was more common in the HA- vs the CAA-ICH group (19% vs 7.8%; p = 0.001). In multivariable logistic regression, presence of multiple subcortical spots was associated with lobar CMBs (odds ratio [OR] 1.23; 95% confidence interval [CI] 1.01-1.50, p = 0.039) and high degree of centrum semiovale EPVS (OR 2.43; 95% CI 1.56-3.80, p < 0.0001). By contrast, age (OR 1.05; 95% CI 1.02-1.09, p = 0.002), deep CMBs (OR 2.46; 95% CI 1.44-4.20, p = 0.001), total WMH volume (OR 1.02; 95% CI 1.01-1.04, p = 0.002), and high BG EPVS degree (OR 8.81; 95% CI 3.37-23.02, p < 0.0001) were predictors of peri-BG WMH pattern. CONCLUSION Different patterns of subcortical leukoaraiosis visually identified on MRI might provide insights into the dominant underlying microangiopathy type as well as mechanisms of tissue injury in patients with ICH.
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Affiliation(s)
- Andreas Charidimou
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center (A.C., G.B., K.H., E.A., E.S.v.E., P.F., Y.R., A.A., A. Vashkevich, Z.Y.D., K.M.S., S.M.-R., J.R., A. Viswanathan, S.M.G., M.E.G.), and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital (J.R.), Harvard Medical School, Boston, MA
| | - Gregoire Boulouis
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center (A.C., G.B., K.H., E.A., E.S.v.E., P.F., Y.R., A.A., A. Vashkevich, Z.Y.D., K.M.S., S.M.-R., J.R., A. Viswanathan, S.M.G., M.E.G.), and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital (J.R.), Harvard Medical School, Boston, MA
| | - Kellen Haley
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center (A.C., G.B., K.H., E.A., E.S.v.E., P.F., Y.R., A.A., A. Vashkevich, Z.Y.D., K.M.S., S.M.-R., J.R., A. Viswanathan, S.M.G., M.E.G.), and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital (J.R.), Harvard Medical School, Boston, MA
| | - Eitan Auriel
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center (A.C., G.B., K.H., E.A., E.S.v.E., P.F., Y.R., A.A., A. Vashkevich, Z.Y.D., K.M.S., S.M.-R., J.R., A. Viswanathan, S.M.G., M.E.G.), and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital (J.R.), Harvard Medical School, Boston, MA
| | - Ellis S van Etten
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center (A.C., G.B., K.H., E.A., E.S.v.E., P.F., Y.R., A.A., A. Vashkevich, Z.Y.D., K.M.S., S.M.-R., J.R., A. Viswanathan, S.M.G., M.E.G.), and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital (J.R.), Harvard Medical School, Boston, MA
| | - Panagiotis Fotiadis
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center (A.C., G.B., K.H., E.A., E.S.v.E., P.F., Y.R., A.A., A. Vashkevich, Z.Y.D., K.M.S., S.M.-R., J.R., A. Viswanathan, S.M.G., M.E.G.), and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital (J.R.), Harvard Medical School, Boston, MA
| | - Yael Reijmer
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center (A.C., G.B., K.H., E.A., E.S.v.E., P.F., Y.R., A.A., A. Vashkevich, Z.Y.D., K.M.S., S.M.-R., J.R., A. Viswanathan, S.M.G., M.E.G.), and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital (J.R.), Harvard Medical School, Boston, MA
| | - Alison Ayres
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center (A.C., G.B., K.H., E.A., E.S.v.E., P.F., Y.R., A.A., A. Vashkevich, Z.Y.D., K.M.S., S.M.-R., J.R., A. Viswanathan, S.M.G., M.E.G.), and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital (J.R.), Harvard Medical School, Boston, MA
| | - Anastasia Vashkevich
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center (A.C., G.B., K.H., E.A., E.S.v.E., P.F., Y.R., A.A., A. Vashkevich, Z.Y.D., K.M.S., S.M.-R., J.R., A. Viswanathan, S.M.G., M.E.G.), and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital (J.R.), Harvard Medical School, Boston, MA
| | - Zora Y Dipucchio
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center (A.C., G.B., K.H., E.A., E.S.v.E., P.F., Y.R., A.A., A. Vashkevich, Z.Y.D., K.M.S., S.M.-R., J.R., A. Viswanathan, S.M.G., M.E.G.), and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital (J.R.), Harvard Medical School, Boston, MA
| | - Kristin M Schwab
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center (A.C., G.B., K.H., E.A., E.S.v.E., P.F., Y.R., A.A., A. Vashkevich, Z.Y.D., K.M.S., S.M.-R., J.R., A. Viswanathan, S.M.G., M.E.G.), and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital (J.R.), Harvard Medical School, Boston, MA
| | - Sergi Martinez-Ramirez
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center (A.C., G.B., K.H., E.A., E.S.v.E., P.F., Y.R., A.A., A. Vashkevich, Z.Y.D., K.M.S., S.M.-R., J.R., A. Viswanathan, S.M.G., M.E.G.), and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital (J.R.), Harvard Medical School, Boston, MA
| | - Jonathan Rosand
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center (A.C., G.B., K.H., E.A., E.S.v.E., P.F., Y.R., A.A., A. Vashkevich, Z.Y.D., K.M.S., S.M.-R., J.R., A. Viswanathan, S.M.G., M.E.G.), and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital (J.R.), Harvard Medical School, Boston, MA
| | - Anand Viswanathan
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center (A.C., G.B., K.H., E.A., E.S.v.E., P.F., Y.R., A.A., A. Vashkevich, Z.Y.D., K.M.S., S.M.-R., J.R., A. Viswanathan, S.M.G., M.E.G.), and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital (J.R.), Harvard Medical School, Boston, MA
| | - Steven M Greenberg
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center (A.C., G.B., K.H., E.A., E.S.v.E., P.F., Y.R., A.A., A. Vashkevich, Z.Y.D., K.M.S., S.M.-R., J.R., A. Viswanathan, S.M.G., M.E.G.), and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital (J.R.), Harvard Medical School, Boston, MA
| | - M Edip Gurol
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center (A.C., G.B., K.H., E.A., E.S.v.E., P.F., Y.R., A.A., A. Vashkevich, Z.Y.D., K.M.S., S.M.-R., J.R., A. Viswanathan, S.M.G., M.E.G.), and Division of Neurocritical Care and Emergency Neurology, Massachusetts General Hospital (J.R.), Harvard Medical School, Boston, MA.
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Reijmer YD, van Veluw SJ, Greenberg SM. Ischemic brain injury in cerebral amyloid angiopathy. J Cereb Blood Flow Metab 2016; 36:40-54. [PMID: 25944592 PMCID: PMC4758563 DOI: 10.1038/jcbfm.2015.88] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Revised: 03/24/2015] [Accepted: 03/26/2015] [Indexed: 12/16/2022]
Abstract
Cerebral amyloid angiopathy (CAA) is a common form of cerebral small vessel disease and an important risk factor for intracerebral hemorrhage and cognitive impairment. While the majority of research has focused on the hemorrhagic manifestation of CAA, its ischemic manifestations appear to have substantial clinical relevance as well. Findings from imaging and pathologic studies indicate that ischemic lesions are common in CAA, including white-matter hyperintensities, microinfarcts, and microstructural tissue abnormalities as detected with diffusion tensor imaging. Furthermore, imaging markers of ischemic disease show a robust association with cognition, independent of age, hemorrhagic lesions, and traditional vascular risk factors. Widespread ischemic tissue injury may affect cognition by disrupting white-matter connectivity, thereby hampering communication between brain regions. Challenges are to identify imaging markers that are able to capture widespread microvascular lesion burden in vivo and to further unravel the etiology of ischemic tissue injury by linking structural magnetic resonance imaging (MRI) abnormalities to their underlying pathophysiology and histopathology. A better understanding of the underlying mechanisms of ischemic brain injury in CAA will be a key step toward new interventions to improve long-term cognitive outcomes for patients with CAA.
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Affiliation(s)
- Yael D Reijmer
- Department of Neurology, Hemorrhagic Stroke Research Program, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Susanne J van Veluw
- Department of Neurology, Hemorrhagic Stroke Research Program, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Department of Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Steven M Greenberg
- Department of Neurology, Hemorrhagic Stroke Research Program, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
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Cacciottolo M, Christensen A, Moser A, Liu J, Pike CJ, Smith C, LaDu MJ, Sullivan PM, Morgan TE, Dolzhenko E, Charidimou A, Wahlund LO, Wiberg MK, Shams S, Chiang GCY, Finch CE. The APOE4 allele shows opposite sex bias in microbleeds and Alzheimer's disease of humans and mice. Neurobiol Aging 2016; 37:47-57. [PMID: 26686669 PMCID: PMC4687024 DOI: 10.1016/j.neurobiolaging.2015.10.010] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 10/06/2015] [Accepted: 10/11/2015] [Indexed: 12/21/2022]
Abstract
The apolipoprotein APOE4 allele confers greater risk of Alzheimer's disease (AD) for women than men, in conjunction with greater clinical deficits per unit of AD neuropathology (plaques, tangles). Cerebral microbleeds, which contribute to cognitive dysfunctions during AD, also show APOE4 excess, but sex-APOE allele interactions are not described. We report that elderly men diagnosed for mild cognitive impairment and AD showed a higher risk of cerebral cortex microbleeds with APOE4 allele dose effect in 2 clinical cohorts (ADNI and KIDS). Sex-APOE interactions were further analyzed in EFAD mice carrying human APOE alleles and familial AD genes (5XFAD (+/-) /human APOE(+/+)). At 7 months, E4FAD mice had cerebral cortex microbleeds with female excess, in contrast to humans. Cerebral amyloid angiopathy, plaques, and soluble Aβ also showed female excess. Both the cerebral microbleeds and cerebral amyloid angiopathy increased in proportion to individual Aβ load. In humans, the opposite sex bias of APOE4 allele for microbleeds versus the plaques and tangles is the first example of organ-specific, sex-linked APOE allele effects, and further shows AD as a uniquely human condition.
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Affiliation(s)
- Mafalda Cacciottolo
- Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA
| | - Amy Christensen
- Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA
| | - Alexandra Moser
- Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA
| | - Jiahui Liu
- Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA
| | - Christian J Pike
- Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA
| | - Conor Smith
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
| | - Mary Jo LaDu
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
| | - Patrick M Sullivan
- Department of Medicine, Duke University, Durham VA Medical Center and GRECC, Durham, NC, USA
| | - Todd E Morgan
- Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA
| | - Egor Dolzhenko
- Department of Molecular and Computational Biology, University of Southern California, Los Angeles, CA, USA
| | - Andreas Charidimou
- Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston, MA, USA
| | - Lars-Olof Wahlund
- Department of Neurobiology, Care Sciences, and Society, Karolinska Institutet, Stockholm, Sweden; Division of Clinical Geriatrics, Karolinska University Hospital, Stockholm, Sweden
| | - Maria Kristofferson Wiberg
- Division of Medical Imaging and Technology, Department of Clinical Science, Intervention, and Technology, Karolinska Institutet, Stockholm, Sweden; Department of Radiology, Karolinska University Hospital, Stockholm, Sweden
| | - Sara Shams
- Division of Medical Imaging and Technology, Department of Clinical Science, Intervention, and Technology, Karolinska Institutet, Stockholm, Sweden; Department of Radiology, Karolinska University Hospital, Stockholm, Sweden
| | | | - Caleb E Finch
- Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA; Department of Molecular and Computational Biology, University of Southern California, Los Angeles, CA, USA; Department of Biological Sciences, Dornsife College, University of Southern California, Los Angeles, CA, USA.
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139
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Banerjee G, Wilson D, Jäger HR, Werring DJ. Novel imaging techniques in cerebral small vessel diseases and vascular cognitive impairment. Biochim Biophys Acta Mol Basis Dis 2015; 1862:926-38. [PMID: 26687324 DOI: 10.1016/j.bbadis.2015.12.010] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Revised: 12/07/2015] [Accepted: 12/08/2015] [Indexed: 11/27/2022]
Abstract
Dementia is a global growing concern, affecting over 35 million people with a global economic impact of over $604 billion US. With an ageing population the number of people affected is expected double over the next two decades. Vascular cognitive impairment can be caused by various types of cerebrovascular disease, including cortical and subcortical infarcts, and the more diffuse white matter injury due to cerebral small vessel disease. Although this type of cognitive impairment is usually considered the second most common form of dementia after Alzheimer's disease, there is increasing recognition of the vascular contribution to neurodegeneration, with both pathologies frequently coexisting. The aim of this review is to highlight the recent advances in the understanding of vascular cognitive impairment, with a focus on small vessel diseases of the brain. We discuss recently identified small vessel imaging markers that have been associated with cognitive impairment, namely cerebral microbleeds, enlarged perivascular spaces, cortical superficial siderosis, and microinfarcts. We will also consider quantitative techniques including diffusion tensor imaging, magnetic resonance perfusion imaging with arterial spin labelling, functional magnetic resonance imaging and positron emission tomography. As well as potentially shedding light on the mechanism by which cerebral small vessel diseases cause dementia, these novel imaging biomarkers are also of increasing relevance given their ability to guide diagnosis and reflect disease progression, which may in the future be useful for therapeutic interventions. This article is part of a Special Issue entitled: Vascular Contributions to Cognitive Impairment and Dementia edited by M. Paul Murphy, Roderick A. Corriveau and Donna M. Wilcock.
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Affiliation(s)
- Gargi Banerjee
- UCL Stroke Research Centre, Department of Brain Repair & Rehabilitation, UCL Institute of Neurology, 10-12 Russell Square, London WC1B 3EE, UK
| | - Duncan Wilson
- UCL Stroke Research Centre, Department of Brain Repair & Rehabilitation, UCL Institute of Neurology, 10-12 Russell Square, London WC1B 3EE, UK
| | - Hans R Jäger
- Neuroradiological Academic Unit, Department of Brain Repair and Rehabilitation, UCL Institute of Neurology and the National Hospital for Neurology and Neurosurgery, London WC1N 3BG, UK
| | - David J Werring
- UCL Stroke Research Centre, Department of Brain Repair & Rehabilitation, UCL Institute of Neurology, 10-12 Russell Square, London WC1B 3EE, UK
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140
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Viswanathan A, Greenberg SM, Scheltens P. Role of Vascular Disease in Alzheimer-Like Progressive Cognitive Impairment. Stroke 2015; 47:577-80. [PMID: 26604252 DOI: 10.1161/strokeaha.115.009010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Anand Viswanathan
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston (A.V., S.M.G.); and Department of Neurology, VU University Medical Center, Amsterdam, The Netherlands (P.S.)
| | - Steven M Greenberg
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston (A.V., S.M.G.); and Department of Neurology, VU University Medical Center, Amsterdam, The Netherlands (P.S.).
| | - Philip Scheltens
- From the Hemorrhagic Stroke Research Program, Department of Neurology, Massachusetts General Hospital Stroke Research Center, Harvard Medical School, Boston (A.V., S.M.G.); and Department of Neurology, VU University Medical Center, Amsterdam, The Netherlands (P.S.)
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141
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Tuladhar AM, van Dijk E, Zwiers MP, van Norden AGW, de Laat KF, Shumskaya E, Norris DG, de Leeuw FE. Structural network connectivity and cognition in cerebral small vessel disease. Hum Brain Mapp 2015; 37:300-10. [PMID: 26466741 DOI: 10.1002/hbm.23032] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 08/28/2015] [Accepted: 10/05/2015] [Indexed: 12/17/2022] Open
Abstract
Cerebral small vessel disease (SVD), including white matter hyperintensities (WMH), lacunes and microbleeds, and brain atrophy, are related to cognitive impairment. However, these magnetic resonance imaging (MRI) markers for SVD do not account for all the clinical variances observed in subjects with SVD. Here, we investigated the relation between conventional MRI markers for SVD, network efficiency and cognitive performance in 436 nondemented elderly with cerebral SVD. We computed a weighted structural connectivity network from the diffusion tensor imaging and deterministic streamlining. We found that SVD-severity (indicated by higher WMH load, number of lacunes and microbleeds, and lower total brain volume) was related to networks with lower density, connection strengths, and network efficiency, and to lower scores on cognitive performance. In multiple regressions models, network efficiency remained significantly associated with cognitive index and psychomotor speed, independent of MRI markers for SVD and mediated the associations between these markers and cognition. This study provides evidence that network (in)efficiency might drive the association between SVD and cognitive performance. This highlights the importance of network analysis in our understanding of SVD-related cognitive impairment in addition to conventional MRI markers for SVD and might provide an useful tool as disease marker.
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Affiliation(s)
- Anil M Tuladhar
- Department of Neurology, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Centre for Neuroscience, Nijmegen, the Netherlands.,Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, the Netherlands
| | - Ewoud van Dijk
- Department of Neurology, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Centre for Neuroscience, Nijmegen, the Netherlands
| | - Marcel P Zwiers
- Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, the Netherlands.,Department of Psychiatry, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands
| | | | | | - Elena Shumskaya
- Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, the Netherlands.,Centre for Cognition, Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - David G Norris
- Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, the Netherlands.,Erwin L. Hahn Institute for Magnetic Resonance Imaging, University of Duisburg-Essen, Essen, Germany.,MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, the Netherlands
| | - Frank-Erik de Leeuw
- Department of Neurology, Radboud University Nijmegen Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Centre for Neuroscience, Nijmegen, the Netherlands
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142
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Aberrant white matter networks mediate cognitive impairment in patients with silent lacunar infarcts in basal ganglia territory. J Cereb Blood Flow Metab 2015; 35:1426-34. [PMID: 25873426 PMCID: PMC4640338 DOI: 10.1038/jcbfm.2015.67] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 02/16/2015] [Accepted: 03/16/2015] [Indexed: 01/12/2023]
Abstract
Silent lacunar infarcts, which are present in over 20% of healthy elderly individuals, are associated with subtle deficits in cognitive functions. However, it remains largely unclear how these silent brain infarcts lead to cognitive deficits and even dementia. Here, we used diffusion tensor imaging tractography and graph theory to examine the topological organization of white matter networks in 27 patients with silent lacunar infarcts in the basal ganglia territory and 30 healthy controls. A whole-brain white matter network was constructed for each subject, where the graph nodes represented brain regions and the edges represented interregional white matter tracts. Compared with the controls, the patients exhibited a significant reduction in local efficiency and global efficiency. In addition, a total of eighteen brain regions showed significantly reduced nodal efficiency in patients. Intriguingly, nodal efficiency-behavior associations were significantly different between the two groups. The present findings provide new aspects into our understanding of silent infarcts that even small lesions in subcortical brain regions may affect large-scale cortical white matter network, as such may be the link between subcortical silent infarcts and the associated cognitive impairments. Our findings highlight the need for network-level neuroimaging assessment and more medical care for individuals with silent subcortical infarcts.
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