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Hampel H, Elhage A, Cho M, Apostolova LG, Nicoll JAR, Atri A. Amyloid-related imaging abnormalities (ARIA): radiological, biological and clinical characteristics. Brain 2023; 146:4414-4424. [PMID: 37280110 PMCID: PMC10629981 DOI: 10.1093/brain/awad188] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 05/03/2023] [Accepted: 05/05/2023] [Indexed: 06/08/2023] Open
Abstract
Excess accumulation and aggregation of toxic soluble and insoluble amyloid-β species in the brain are a major hallmark of Alzheimer's disease. Randomized clinical trials show reduced brain amyloid-β deposits using monoclonal antibodies that target amyloid-β and have identified MRI signal abnormalities called amyloid-related imaging abnormalities (ARIA) as possible spontaneous or treatment-related adverse events. This review provides a comprehensive state-of-the-art conceptual review of radiological features, clinical detection and classification challenges, pathophysiology, underlying biological mechanism(s) and risk factors/predictors associated with ARIA. We summarize the existing literature and current lines of evidence with ARIA-oedema/effusion (ARIA-E) and ARIA-haemosiderosis/microhaemorrhages (ARIA-H) seen across anti-amyloid clinical trials and therapeutic development. Both forms of ARIA may occur, often early, during anti-amyloid-β monoclonal antibody treatment. Across randomized controlled trials, most ARIA cases were asymptomatic. Symptomatic ARIA-E cases often occurred at higher doses and resolved within 3-4 months or upon treatment cessation. Apolipoprotein E haplotype and treatment dosage are major risk factors for ARIA-E and ARIA-H. Presence of any microhaemorrhage on baseline MRI increases the risk of ARIA. ARIA shares many clinical, biological and pathophysiological features with Alzheimer's disease and cerebral amyloid angiopathy. There is a great need to conceptually link the evident synergistic interplay associated with such underlying conditions to allow clinicians and researchers to further understand, deliberate and investigate on the combined effects of these multiple pathophysiological processes. Moreover, this review article aims to better assist clinicians in detection (either observed via symptoms or visually on MRI), management based on appropriate use recommendations, and general preparedness and awareness when ARIA are observed as well as researchers in the fundamental understanding of the various antibodies in development and their associated risks of ARIA. To facilitate ARIA detection in clinical trials and clinical practice, we recommend the implementation of standardized MRI protocols and rigorous reporting standards. With the availability of approved amyloid-β therapies in the clinic, standardized and rigorous clinical and radiological monitoring and management protocols are required to effectively detect, monitor, and manage ARIA in real-world clinical settings.
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Affiliation(s)
- Harald Hampel
- Eisai Inc., Alzheimer’s Disease and Brain Health, Nutley, NJ 07110, USA
| | - Aya Elhage
- Eisai Inc., Alzheimer’s Disease and Brain Health, Nutley, NJ 07110, USA
| | - Min Cho
- Eisai Inc., Alzheimer’s Disease and Brain Health, Nutley, NJ 07110, USA
| | - Liana G Apostolova
- Department of Neurology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Radiology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - James A R Nicoll
- Division of Clinical Neurosciences, Clinical and Experimental Sciences, University of Southampton, Southampton SO16 6YD, UK
- Department of Cellular Pathology, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
| | - Alireza Atri
- Banner Sun Health Research Institute, Banner Health, Sun City, AZ 85351, USA
- Center for Brain/Mind Medicine, Department of Neurology, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
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2
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Bergeret S, Queneau M, Rodallec M, Curis E, Dumurgier J, Hugon J, Paquet C, Farid K, Baron JC. [ 18 F]FDG PET may differentiate cerebral amyloid angiopathy from Alzheimer's disease. Eur J Neurol 2021; 28:1511-1519. [PMID: 33460498 DOI: 10.1111/ene.14743] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 01/07/2021] [Accepted: 01/09/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND Cerebral amyloid angiopathy (CAA) is a frequent cause of both intracerebral hemorrhage (ICH) and cognitive impairment in the elderly. Diagnosis relies on the Boston criteria, which use magnetic resonance imaging markers including ≥2 exclusively lobar cerebral microbleeds (lCMBs). Although amyloid positron emission tomography (PET) may provide molecular diagnosis, its specificity relative to Alzheimer's disease (AD) is limited due to the prevalence of positive amyloid PET in cognitively normal elderly. Using early-phase 11 C-Pittsburgh compound B as surrogate for tissue perfusion, a significantly lower occipital/posterior cingulate (O/PC) tracer uptake ratio in probable CAA relative to AD was recently reported, consistent with histopathological lesion distribution. We tested whether this finding could be reproduced using [18 F]fluorodeoxyglucose (FDG)-PET, a widely available modality that correlates well with early-phase amyloid PET in both healthy subjects and AD. METHODS From a large memory clinic database, we retrospectively included 14 patients with probable CAA (Boston criteria) and 21 patients with no lCMB fulfilling AD criteria including cerebrospinal fluid biomarkers. In all, [18 F]FDG-PET/computed tomography (CT) was available as part of routine care. No subject had a clinical history of ICH. Regional standardized [18 F]FDG uptake values normalized to the pons (standard uptake value ratio [SUVr]) were obtained, and the O/PC ratio was calculated. RESULTS The SUVr O/PC ratio was significantly lower in CAA versus AD (1.02 ± 0.14 vs. 1.19 ± 0.18, respectively; p = 0.024). CONCLUSIONS Despite the small sample, our findings are consistent with the previous early-phase amyloid PET study. Thus, [18 F]FDG-PET may help differentiate CAA from AD, particularly in cases of amyloid PET positivity. Larger prospective studies, including in CAA-related ICH, are however warranted.
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Affiliation(s)
- Sébastien Bergeret
- Department of Nuclear Medicine, CHU French West Indies, Fort-de-France, France
| | - Mathieu Queneau
- Department of Nuclear Medicine, Centre Cardiologique du Nord, Saint-Denis, France
| | - Mathieu Rodallec
- Department of Radiology, Centre Cardiologique du Nord, Saint-Denis, France
| | - Emmanuel Curis
- Laboratoire de Biomathématiques, EA 7537 "BioSTM", Faculté de Pharmacie, Université de Paris, Paris, France.,Service de Biostatistiques et d'Information Médicale, Hôpital Saint-Louis, APHP, Paris, France
| | - Julien Dumurgier
- INSERM UMR-S 1144: Therapeutic Optimization in Neuropsychopharmacology, Université de Paris, Paris, France
| | - Jacques Hugon
- INSERM UMR-S 1144: Therapeutic Optimization in Neuropsychopharmacology, Université de Paris, Paris, France.,Cognitive Neurology Center, APHP, Saint-Louis Lariboisière Fernand-Widal Hospital Group, Paris, France
| | - Claire Paquet
- INSERM UMR-S 1144: Therapeutic Optimization in Neuropsychopharmacology, Université de Paris, Paris, France.,Cognitive Neurology Center, APHP, Saint-Louis Lariboisière Fernand-Widal Hospital Group, Paris, France
| | - Karim Farid
- Department of Nuclear Medicine, CHU French West Indies, Fort-de-France, France.,INSERM UMR-S 1144: Therapeutic Optimization in Neuropsychopharmacology, Université de Paris, Paris, France
| | - Jean-Claude Baron
- Department of Neurology, Sainte-Anne Hospital, Université de Paris, Paris, France.,INSERM U1266: Institut de Psychiatrie et Neurosciences de Paris, Université de Paris, Paris, France
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3
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Abstract
Alzheimer's disease (AD) care requires timely diagnosis and multidisciplinary management. Evaluation involves structured patient and caregiver history and symptom-function reviews, examination, and testing (laboratory and neuroimaging) to delineate impairment level, determine the cognitive-behavioral syndrome, and diagnose cause. Clinical biomarkers are available to aid high confidence in etiologic diagnosis. Management uses psychoeducation, shared goal setting, and patient-caregiver dyad decision making. When combined, pharmacologic and nonpharmacologic therapies mitigate symptoms and reduce clinical progression and care burden. AD biopathologic processes develop over decades before symptoms manifest; this period is increasingly targeted in research as an opportunity to best delay or prevent AD dementia.
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Affiliation(s)
- Alireza Atri
- Banner Sun Health Research Institute, Banner Health, 10515 W Santa Fe Drive, Sun City, AZ 85351, USA; Department of Neurology, Brigham and Women's Hospital, 60 Fenwood Road, Boston, MA 02115, USA; Harvard Medical School, 25 Shattuck Street, Boston, MA 02115, USA.
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4
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Wilker EH, Martinez-Ramirez S, Kloog I, Schwartz J, Mostofsky E, Koutrakis P, Mittleman MA, Viswanathan A. Fine Particulate Matter, Residential Proximity to Major Roads, and Markers of Small Vessel Disease in a Memory Study Population. J Alzheimers Dis 2018; 53:1315-23. [PMID: 27372639 DOI: 10.3233/jad-151143] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Long-term exposure to ambient air pollution has been associated with impaired cognitive function and vascular disease in older adults, but little is known about these associations among people with concerns about memory loss. OBJECTIVE To examine associations between exposures to fine particulate matter and residential proximity to major roads and markers of small vessel disease. METHODS From 2004-2010, 236 participants in the Massachusetts Alzheimer's Disease Research Center Longitudinal Cohort participated in neuroimaging studies. Residential proximity to major roads and estimated 2003 residential annual average of fine particulate air pollution (PM2.5) were linked to measures of brain parenchymal fraction (BPF), white matter hyperintensities (WMH), and cerebral microbleeds. Associations were modeled using linear and logistic regression and adjusted for clinical and lifestyle factors. RESULTS In this population (median age [interquartile range] = 74 [12], 57% female) living in a region with median 2003 PM2.5 annual average below the current Environmental Protection Agency (EPA) standard, there were no associations between living closer to a major roadway or for a 2μg/m3 increment in PM2.5 and smaller BPF, greater WMH volume, or a higher odds of microbleeds. However, a 2μg/m3 increment in PM2.5 was associated with -0.19 (95% Confidence Interval (CI): -0.37, -0.005) lower natural log-transformed WMH volume. Other associations had wide confidence intervals. CONCLUSIONS In this population, where median 2003 estimated PM2.5 levels were below the current EPA standard, we observed no pattern of association between residential proximity to major roads or 2003 average PM2.5 and greater burden of small vessel disease or neurodegeneration.
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Affiliation(s)
- Elissa H Wilker
- Cardiovascular Division, Beth Israel Deaconess Medical Center, Boston, MA, USA.,Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.,Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Sergi Martinez-Ramirez
- Hemorrhagic Stroke Research Group, Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
| | - Itai Kloog
- Department of Geography and Environmental Development, Ben Gurion University of the Negev, Beer Sheva, Israel
| | - Joel Schwartz
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.,Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Elizabeth Mostofsky
- Cardiovascular Division, Beth Israel Deaconess Medical Center, Boston, MA, USA.,Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Petros Koutrakis
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Murray A Mittleman
- Cardiovascular Division, Beth Israel Deaconess Medical Center, Boston, MA, USA.,Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.,Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Anand Viswanathan
- Hemorrhagic Stroke Research Group, Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
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5
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Atri A. Imaging of neurodegenerative cognitive and behavioral disorders: practical considerations for dementia clinical practice. HANDBOOK OF CLINICAL NEUROLOGY 2016; 136:971-984. [PMID: 27430453 DOI: 10.1016/b978-0-444-53486-6.00050-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
This chapter reviews clinical applications and imaging findings useful in medical practice relating to neurodegenerative cognitive/dementing disorders. The preponderance of evidence and consensus guidelines support an essential role of multitiered neuroimaging in the evaluation and management of neurodegenerative cognitive/dementia syndrome that range in severity from mild impairments to frank dementia. Additionally, imaging features are incorporated in updated clinical and research diagnostic criteria for most dementias, including Alzheimer's disease (AD), Dementia with Lewy bodies (DLB), Frontotemporal Lobar Degenerations/Frontotemporal Dementia (FTD), and Vascular Cognitive Impairment (VCI). Best clinical practices dictate that structural imaging, preferably with magnetic resonance imaging (MRI) when possible and computed tomography when not, be obtained as a first-tier approach during the course of a thorough clinical evaluation to improve diagnostic confidence and assess for nonneurodegenerative treatable conditions that may cause or substantially contribute to cognitive/behavioral symptoms or which may dictate a substantial change in management. These conditions include less common structural (e.g., mass lesions such as tumors and hematomas; normal-pressure hydrocephalus), inflammatory, autoimmune and infectious conditions, and more common comorbid contributing conditions (e.g., vascular cerebral injury causing leukoaraiosis, infarcts, or microhemorrhages) that can produce a mixed dementia syndrome. When, after appropriate clinical, cognitive/neuropsychologic, and structural neuroimaging assessment, a dementia specialist remains in doubt regarding etiology and appropriate management, second-tier imaging with molecular methods, preferably with fluorodexoyglucose positron emission tomography (PET) (or single-photon emission computed tomography if PET is unavailable) can provide more diagnostic specificity (e.g., help differentiate between atypical AD and FTD as the etiology for a frontal/dysexecutive syndrome). The potential clinical utility of other promising methods, whether already approved for use (e.g., amyloid PET) or as yet only used in research (e.g., tau PET, functional MRI, diffusor tensor imaging), remains to be proven for widespread use in community practice. However, these constitute unreimbursed third-tier options that merit further study for clinical and cost-effective utility. In the future, combination use of imaging methods will likely improve diagnostic accuracy.
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Affiliation(s)
- Alireza Atri
- Ray Dolby Brain Health Center, California Pacific Medical Center Research Institute, Sutter Health, San Francisco, CA, USA.
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6
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Shams S, Wahlund LO. Cerebral microbleeds as a biomarker in Alzheimer's disease? A review in the field. Biomark Med 2015; 10:9-18. [PMID: 26641942 DOI: 10.2217/bmm.15.101] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Cerebral microbleeds (CMBs) are a marker of small vessel disease, increasingly recognized as being of importance in the Alzheimer's disease (AD) process. CMBs influence in AD, and its longitudinal impact on disease progression is however still unknown. CMBs show several associations with AD across studies, are associated with decreased cerebrospinal fluid amyloid levels and are related with the ApoE ϵ4 allele, as well as other imaging manifestations typical for small vessel disease. CMBs, in addition to other markers of small vessel disease, are important to discover further in order to discern possible AD phenotypes.
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Affiliation(s)
- Sara Shams
- Department of Clinical Science, Intervention & Technology, Division of Medical Imaging & Technology, Karolinska Institutet, Stockholm, Sweden
| | - Lars-Olof Wahlund
- Department of Neurobiology, Care Sciences & Society, Karolinska Institutet, Stockholm, Sweden. Division of Clinical Geriatrics, Karolinska University Hospital, Stockholm, Sweden
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7
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Sepehry AA, Lang D, Hsiung GY, Rauscher A. Prevalence of Brain Microbleeds in Alzheimer Disease: A Systematic Review and Meta-Analysis on the Influence of Neuroimaging Techniques. AJNR Am J Neuroradiol 2015; 37:215-22. [PMID: 26635284 DOI: 10.3174/ajnr.a4525] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 07/11/2015] [Indexed: 12/30/2022]
Abstract
BACKGROUND AND PURPOSE The literature on the prevalence of Alzheimer disease-associated cerebral microbleeds assessed with MR imaging shows considerable heterogeneity in terms of imaging techniques and parameters. Our aim was to perform a meta-analysis of the role of imaging techniques, including image acquisition, field strength and scanner type, and clinical and demographic factors on the reported prevalence of microbleeds in Alzheimer disease. MATERIALS AND METHODS The prevalence of microbleeds was examined with respect to a priori-selected moderating variables via meta-analytic tools of literature reports. RESULTS Fourteen unique studies providing 15 microbleed prevalence rates met the selection criteria for inclusion. The aggregate prevalence of microbleeds was 24% (95% CI, 19%-28%). Scan (SWI = 40%, gradient echo = 18%, EPI = 19%) and field strength (slope = 0.39; standard error = 15, P < .01) influenced the prevalence of microbleeds. The associations between microbleeds and age, sex, and global cognitive status were not significant. After updating the literature, the aggregate prevalence remained in the 95% CI range. CONCLUSIONS Imaging technique and field strength are strongly associated with the prevalence of microbleeds over the global aggregate. Standardized imaging protocols for identification of microbleeds are recommended to minimize confounds.
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Affiliation(s)
- A A Sepehry
- From the Division of Neurology (A.A.S., G.-Y.H.), Department of Medicine Departments of Paediatrics (A.A.S., A.R.)
| | - D Lang
- Radiology (D.L.); University of British Columbia, Vancouver, British Columbia, Canada
| | - G-Y Hsiung
- From the Division of Neurology (A.A.S., G.-Y.H.), Department of Medicine
| | - A Rauscher
- Departments of Paediatrics (A.A.S., A.R.)
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8
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Nagasawa J, Kiyozaka T, Ikeda K. Prevalence and clinicoradiological analyses of patients with Alzheimer disease coexisting multiple microbleeds. J Stroke Cerebrovasc Dis 2014; 23:2444-9. [PMID: 25174565 DOI: 10.1016/j.jstrokecerebrovasdis.2014.05.036] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 05/24/2014] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Pathologic findings of cerebral amyloid angiopathy (CAA) and Alzheimer disease (AD) coexist frequently. Both diseases are associated with β-amyloid deposition and dementia. We aimed to evaluate frequency and clinicoradiological profile of AD patients with multiple microbleeds (MBs). METHODS We reviewed clinical records and magnetic resonance imaging (MRI) findings in patients with probable AD diagnosed by the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), and National Institute of Neurological and Communicative Disorders and Stroke and Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) criteria from 2009 to 2012. Brain MRI was performed at 1.5-T superconducting system, including T2*-weighted gradient-echo imaging. MBs were defined as rounded, hypointense foci less than or equal to 10 mm in size in the brain parenchyma. MBs topography was divided into the lobar (L) and the deep/infratentorial (D/I) region. Multiple MBs were defined as the number greater than or equal to 8 in the L and the D/I territory, respectively. White matter hyperintensities (WMHs) were assessed using the age-related white matter changes scale. Clinicoradiological findings were examined for 1 year. Prevalence and clinicoradiological profiles were studied in patients with multiple L or D/I MBs. RESULTS Five hundred fifty patients (238 men and 312 women) participated in the present study. Mean age (standard deviation) was 78.4 (7.7) years, 78.3 (8.1) years in men and 78.6 (7.5) years in women. A total of 132 patients (55 men and 78 women) had at least 1 MB. Prevalence of MB ≥ 1 was 24%, 23 in men and 25 in women. The ratio of L and D/I MBs were 1.1, .6 in men and 1.8 in women. Multiple MBs were detected in 93 patients (17%), 38 (16%) men and 55 (17%) in women. L distribution was found in 49 patients (9%), 15 men (6%) and 34 women (11%), and D/I distribution in 44 patients (8%), 23 men (10%) and 21 women (7%). Multiple L MBs was associated with faster progression of dementia, cerebral hemorrhage, and increased number of MBs. Multiple D/I MBs were linked to hypertension and WMH scores. CONCLUSIONS The present study indicated that the prevalence of multiple MBs was 17% in Japanese AD patients. The clinicoradiological profile suggested severe degree of CAA in patients with multiple L MBs (9%) and hypertension and aged changes in patients with multiple D/I MBs (8%). T2*-weighted imaging is a useful tool for evaluating degree of CAA and hypertensive vascular changes. We should pay more attention to management and care in AD patients with multiple MBs.
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Affiliation(s)
- Junpei Nagasawa
- Department of Neurology, Toho University Omori Medical Center, Tokyo, Japan
| | | | - Ken Ikeda
- Department of Neurology, Toho University Omori Medical Center, Tokyo, Japan.
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Filippi M, Agosta F, Barkhof F, Dubois B, Fox NC, Frisoni GB, Jack CR, Johannsen P, Miller BL, Nestor PJ, Scheltens P, Sorbi S, Teipel S, Thompson PM, Wahlund LO. EFNS task force: the use of neuroimaging in the diagnosis of dementia. Eur J Neurol 2012; 19:e131-40, 1487-501. [DOI: 10.1111/j.1468-1331.2012.03859.x] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Accepted: 07/18/2012] [Indexed: 01/18/2023]
Affiliation(s)
- M. Filippi
- Neuroimaging Research Unit; Division of Neuroscience; Institute of Experimental Neurology; San Raffaele Scientific Institute; Vita-Salute San Raffaele University; Milan Italy
| | - F. Agosta
- Neuroimaging Research Unit; Division of Neuroscience; Institute of Experimental Neurology; San Raffaele Scientific Institute; Vita-Salute San Raffaele University; Milan Italy
| | - F. Barkhof
- Department of Radiology; VU University Medical Center; Amsterdam The Netherlands
| | - B. Dubois
- Centre de Recherche de l'Institut du Cerveau et de la Moelle Epinière; Université Pierre et Marie Curie; Paris France
| | - N. C. Fox
- Dementia Research Centre; Institute of Neurology; University College London; London UK
| | - G. B. Frisoni
- IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli di Brescia; Brescia Italy
| | - C. R. Jack
- Department of Radiology; Mayo Clinic and Foundation; Rochester MN USA
| | - P. Johannsen
- Memory Clinic; Rigshospitalet; Copenhagen University Hospital; Copenhagen Denmark
| | - B. L. Miller
- Memory and Aging Center; University of California; San Francisco CA USA
| | - P. J. Nestor
- Department of Clinical Neuroscience; University of Cambridge; Cambridge UK
| | - P. Scheltens
- Department of Neurology and Alzheimer Center; VU University Medical Center; Amsterdam The Netherlands
| | - S. Sorbi
- Department of Neurological and Psychiatric Sciences; Azienda Ospedaliero-Universitaria di Careggi; Florence Italy
| | - S. Teipel
- Department of Psychiatry; University of Rostock, and German Center for Neuro-degenerative Diseases (DZNE); Rostock Germany
| | - P. M. Thompson
- Department of Neurology; David Geffen School of Medicine at the University of California Los Angeles; Los Angeles CA USA
| | - L.-O. Wahlund
- Division of Clinical Geriatrics; Department of Neurobiology; Karolinska Institute; Stockholm Sweden
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10
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Abstract
Cerebral amyloid angiopathy (CAA) results from deposition of β-amyloid in the media and adventitia of small arteries and capillaries of the leptomeninges and cerebral cortex and is a major cause of lobar intracerebral hemorrhage and cognitive impairment in the elderly. CAA is associated with a high prevalence of magnetic resonance imaging markers of small vessel disease, including cerebral microbleeds and white matter hyperintensities. Although advanced CAA is present in approximately ¼ of brains with Alzheimer disease (AD), fewer than half of CAA cases meet pathologic criteria for AD. This review will discuss the pathophysiology of CAA and focus on new imaging modalities and laboratory biomarkers that may aid in the clinical diagnosis of individuals with the disease.
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Affiliation(s)
- Anand Viswanathan
- Department of Neurology and Clinical Trials Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA.
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11
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Cavalieri M, Schmidt H, Schmidt R. Structural MRI in Normal Aging and Alzheimers Disease: White and Black Spots. NEURODEGENER DIS 2012; 10:253-6. [DOI: 10.1159/000333120] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 09/03/2011] [Indexed: 01/18/2023] Open
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12
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Goos JDC, Teunissen CE, Veerhuis R, Verwey NA, Barkhof F, Blankenstein MA, Scheltens P, van der Flier WM. Microbleeds relate to altered amyloid-β metabolism in Alzheimer's disease. Neurobiol Aging 2011; 33:1011.e1-9. [PMID: 22118945 DOI: 10.1016/j.neurobiolaging.2011.10.026] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Revised: 10/21/2011] [Accepted: 10/23/2011] [Indexed: 10/14/2022]
Abstract
Cerebral microbleeds (MBs) may relate to amyloid in dementia. We selected 26 probable Alzheimer's disease (AD) patients with MBs, 26 age- and sex-matched AD patients without MBs, 11 vascular dementia (VaD) patients, and 22 patients with subjective complaints. We measured amyloid beta 1-42 (Aβ42) and 1-40 (Aβ40) in cerebrospinal fluid (CSF) and plasma, and blood-brain barrier (BBB) function using albumin ratios. CSF Aβ42 was lowest in AD with MBs, whereas Aβ40 was selectively decreased in VaD. In plasma, amyloid-beta was nonsignificantly elevated in VaD compared with controls. Higher albumin ratios in VaD suggested blood-brain barrier dysfunction. A MB pattern suggestive of cerebral amyloid angiopathy (CAA) related to lower CSF Aβ42, while a non-cerebral amyloid angiopathy specific MB distribution related to higher plasma Aβ40. Amyloid-beta is differentially implicated in AD with MBs and VaD. MB distribution related to different amyloid profiles, supporting distinct etiologies. Our results suggest that Aβ42 is retained in cerebrovasculature of AD patients with MBs, while in contrast, VaD patients may possibly drain amyloid.
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Affiliation(s)
- Jeroen D C Goos
- Alzheimer Center, VU University Medical Center, Amsterdam, the Netherlands.
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13
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Kokjohn TA, Maarouf CL, Roher AE. Is Alzheimer's disease amyloidosis the result of a repair mechanism gone astray? Alzheimers Dement 2011; 8:574-83. [PMID: 22047632 DOI: 10.1016/j.jalz.2011.05.2429] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Accepted: 05/17/2011] [Indexed: 01/21/2023]
Abstract
Here, we synthesize several lines of evidence supporting the hypothesis that at least one function of amyloid-β is to serve as a part of the acute response to brain hemodynamic disturbances intended to seal vascular leakage. Given the resilient and adhesive physicochemical properties of amyloid, an abluminal hemostatic repair system might be highly advantageous, if deployed on a limited and short-term basis, in young individuals. However, in the aged, inevitable cardiovascular dysfunction combined with brain microvascular lesions may yield global chronic hypoperfusion that may lead to continuous amyloid deposition and consequential negative effects on neuronal viability. A large body of experimental evidence supports the hypothesis of an amyloid-β rescue function gone astray. Preventing or inducing the removal of amyloid in Alzheimer's disease (AD) has been simultaneously successful and disappointing. Amyloid deposits clearly play major roles in AD, but they may not represent the preeminent factor in dementia pathogenesis. Successful application of AD preventative approaches may hinge on an accurate and comprehensive view of comorbidities, including cardiovascular disease, diabetes, and head trauma.
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Affiliation(s)
- Tyler A Kokjohn
- The Longtine Center for Neurodegenerative Biochemistry, Banner Sun Health Research Institute, Sun City, AZ, USA
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14
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Ferrer I. Cognitive impairment of vascular origin: neuropathology of cognitive impairment of vascular origin. J Neurol Sci 2010; 299:139-49. [PMID: 20846674 DOI: 10.1016/j.jns.2010.08.039] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2010] [Revised: 08/15/2010] [Accepted: 08/24/2010] [Indexed: 12/31/2022]
Abstract
The term cognitive impairment of vascular origin is used to designate global cognitive deficits as well as focal neurological deficits such as aphasia, apraxia and agnosia of vascular/circulatory origin. It has been useful for identifying early clinical and neuroradiological alterations that might permit therapeutic strategies geared to curbing the progression of cerebrovascular disease. Multi-infarct encephalopathy, infarcts in strategic areas, lacunae and lacunar status, Binswanger's encephalopathy, hippocampal sclerosis, cortical granular atrophy and watershed infarcts are common lesions. Hypertension and vascular diseases such as arteriosclerosis, small blood vessel disease, inflammatory diseases of the blood vessels, Sneddon syndrome, cerebral amyloid angiopathies, cerebral autosomic dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), and Maeda's syndrome are causative of cognitive impairment of vascular origin. Other less common causes are hereditary endotheliopathy with retinopathy, neuropathy and strokes (HERNS), cerebro-retinian vasculopathy (CRV), hereditary vascular retinopathy (HVR) (all three linked to 3p21.1-p21.3), hereditary infantile hemiparesis with arteriolar retinopathy and leukoencephalopathy (HIHRATL) (not linked to 3p21), fibromuscular dysplasia, and moya-moya disease. Lack of uniformity of clinical manifestations, the variety of vascular diseases and circulatory factors, the diverse, but often convergent, neuropathological substrates, and the common association with unrelated neurodegenerative diseases in the elderly, make it hard to assume a single clinical approach in the diagnosis and treatment of cognitive impairment of vascular origin. Rather, environmental and genetic risk factors, underlying vascular diseases, associated systemic, metabolic and neurodegenerative diseases and identification of extent and distribution of lesions with morphological and functional neuroimaging methods should be applied in every individual patient.
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Affiliation(s)
- Isidre Ferrer
- Institut de Neuropatologia, Servei Anatomia Patològica, IDIBELL-Hospital Universitari de Bellvitge, 08907 Hospitalet de LLobregat, Spain.
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Kirsch W, McAuley G, Holshouser B, Petersen F, Ayaz M, Vinters HV, Dickson C, Haacke EM, Britt W, Larseng J, Kim I, Mueller C, Schrag M, Kido D. Serial susceptibility weighted MRI measures brain iron and microbleeds in dementia. J Alzheimers Dis 2009; 17:599-609. [PMID: 19433895 DOI: 10.3233/jad-2009-1073] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A new iron sensitive MR sequence (susceptibility weighted imaging - SWI) enabling the simultaneous quantitation of regional brain iron levels and brain microbleeds (BMB) has been acquired serially to study dementia. Cohorts of mildly cognitively impaired (MCI) elderly (n = 73) and cognitively normal participants (n = 33) have been serially evaluated for up to 50 months. SWI phase values (putative iron levels) in 14 brain regions were measured and the number of BMB were counted for each SWI study. SWI phase values showed a left putaminal mean increase of iron (decrease of phase values) over the study duration in 27 participants who progressed to dementia compared to Normals (p = 0.035) and stable MCI (p = 0.01). BMB were detected in 9 out of 26 (38%) MCI participants who progressed to dementia and are a significant risk factor for cognitive failure in MCI participants [risk ratio = 2.06 (95% confidence interval 1.37-3.12)]. SWI is useful to measure regional iron changes and presence of BMB, both of which may be important MR-based biomarkers for neurodegenerative diseases.
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Affiliation(s)
- Wolff Kirsch
- Neurosurgery Center for Research, Training, and Education, Loma Linda University, 11175 Campus Street, Suite 11113, Loma Linda, CA 92350, USA.
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Goos JDC, Kester MI, Barkhof F, Klein M, Blankenstein MA, Scheltens P, van der Flier WM. Patients with Alzheimer disease with multiple microbleeds: relation with cerebrospinal fluid biomarkers and cognition. Stroke 2009; 40:3455-60. [PMID: 19762705 DOI: 10.1161/strokeaha.109.558197] [Citation(s) in RCA: 161] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND AND PURPOSE Microbleeds (MBs) are commonly observed in Alzheimer disease. A minority of patients has multiple MBs. We aimed to investigate associations of multiple MBs in Alzheimer disease with clinical and MRI characteristics and cerebrospinal fluid biomarkers. METHODS Patients with Alzheimer disease with multiple (>or=8) MBs on T2*-weighted MRI were matched for age, sex, and field strength with patients with Alzheimer disease without MBs on a 1:2 basis. We included 21 patients with multiple MBs (73+/-7 years, 33% female) and 42 patients without MBs (72+/-7 years, 38% female). Mini-Mental State Examination was used to assess dementia severity. Cognitive functions were assessed using neuropsychological tests. Medial temporal lobe atrophy (0 to 4), global cortical atrophy (0 to 3), and white matter hyperintensities (0 to 30) were assessed using visual rating scales. In a subset, apolipoprotein E genotype and cerebrospinal fluid amyloid beta 1-42, total tau and tau phosphorylated at threonine 181 were determined. RESULTS Patients with multiple MBs performed worse on Mini-Mental State Examination (multiple MB: 17+/-7; no MB: 22+/-4, P<0.05) despite similar disease duration. Atrophy was not related to presence of MBs, but patients with multiple MBs had more white matter hyperintensities (multiple MB: 8.8+/-4.8; no MB: 3.2+/-3.6, P<0.05). Adjusted for age, sex, white matter hyperintensities, and medial temporal lobe atrophy, the multiple MB group additionally performed worse on Visual Association Test object naming and animal fluency. Patients with multiple MBs had lower cerebrospinal fluid amyloid beta 1-42 levels (307+/-61) than patients without MBs (505+/-201, P<0.05). Adjusted for the same covariates, total tau, and tau phosphorylated at threonine 181 were higher in the multiple MB group. CONCLUSIONS Microbleeds are associated with the clinical manifestation and biochemical hallmarks of Alzheimer disease, suggesting possible involvement of MBs in the pathogenesis of Alzheimer disease.
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Affiliation(s)
- Jeroen D C Goos
- Department of Neurology and Alzheimer Center, VU University Medical Center, Amsterdam, The Netherlands.
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Abstract
Cerebrovascular disease and Alzheimer disease are common diseases of aging and frequently coexist in the same brain. Accumulating evidence suggests that the presence of brain infarction, including silent infarction, influences the course of Alzheimer disease. Conversely, there is evidence that beta-amyloid can impair blood vessel function. Vascular beta-amyloid deposition, also known as cerebral amyloid angiopathy, is associated with vascular dysfunction in animal and human studies. Alzheimer disease is associated with morphological changes in capillary networks, and soluble beta-amyloid produces abnormal vascular responses to physiological and pharmacological stimuli. In this review, we discuss current evidence linking beta-amyloid metabolism with vascular function and morphological changes in animals and humans.
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Affiliation(s)
- Eric E Smith
- Division of Neurology, Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
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Dickerson BC, Bakkour A, Salat DH, Feczko E, Pacheco J, Greve DN, Grodstein F, Wright CI, Blacker D, Rosas HD, Sperling RA, Atri A, Growdon JH, Hyman BT, Morris JC, Fischl B, Buckner RL. The cortical signature of Alzheimer's disease: regionally specific cortical thinning relates to symptom severity in very mild to mild AD dementia and is detectable in asymptomatic amyloid-positive individuals. Cereb Cortex 2009; 19:497-510. [PMID: 18632739 PMCID: PMC2638813 DOI: 10.1093/cercor/bhn113] [Citation(s) in RCA: 751] [Impact Index Per Article: 50.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Alzheimer's disease (AD) is associated with neurodegeneration in vulnerable limbic and heteromodal regions of the cerebral cortex, detectable in vivo using magnetic resonance imaging. It is not clear whether abnormalities of cortical anatomy in AD can be reliably measured across different subject samples, how closely they track symptoms, and whether they are detectable prior to symptoms. An exploratory map of cortical thinning in mild AD was used to define regions of interest that were applied in a hypothesis-driven fashion to other subject samples. Results demonstrate a reliably quantifiable in vivo signature of abnormal cortical anatomy in AD, which parallels known regional vulnerability to AD neuropathology. Thinning in vulnerable cortical regions relates to symptom severity even in the earliest stages of clinical symptoms. Furthermore, subtle thinning is present in asymptomatic older controls with brain amyloid binding as detected with amyloid imaging. The reliability and clinical validity of AD-related cortical thinning suggests potential utility as an imaging biomarker. This "disease signature" approach to cortical morphometry, in which disease effects are mapped across the cortical mantle and then used to define ROIs for hypothesis-driven analyses, may provide a powerful methodological framework for studies of neuropsychiatric diseases.
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Affiliation(s)
- Bradford C Dickerson
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA.
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Cordonnier C. Microsanguinamenti intracerebrali. Neurologia 2009. [DOI: 10.1016/s1634-7072(09)70513-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Schmahmann JD, Smith EE, Eichler FS, Filley CM. Cerebral white matter: neuroanatomy, clinical neurology, and neurobehavioral correlates. Ann N Y Acad Sci 2008; 1142:266-309. [PMID: 18990132 DOI: 10.1196/annals.1444.017] [Citation(s) in RCA: 332] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Lesions of the cerebral white matter (WM) result in focal neurobehavioral syndromes, neuropsychiatric phenomena, and dementia. The cerebral WM contains fiber pathways that convey axons linking cerebral cortical areas with each other and with subcortical structures, facilitating the distributed neural circuits that subserve sensorimotor function, intellect, and emotion. Recent neuroanatomical investigations reveal that these neural circuits are topographically linked by five groupings of fiber tracts emanating from every neocortical area: (1) cortico-cortical association fibers; (2) corticostriatal fibers; (3) commissural fibers; and cortico-subcortical pathways to (4) thalamus and (5) pontocerebellar system, brain stem, and/or spinal cord. Lesions of association fibers prevent communication between cortical areas engaged in different domains of behavior. Lesions of subcortical structures or projection/striatal fibers disrupt the contribution of subcortical nodes to behavior. Disconnection syndromes thus result from lesions of the cerebral cortex, subcortical structures, and WM tracts that link the nodes that make up the distributed circuits. The nature and the severity of the clinical manifestations of WM lesions are determined, in large part, by the location of the pathology: discrete neurological and neuropsychiatric symptoms result from focal WM lesions, whereas cognitive impairment across multiple domains--WM dementia--occurs in the setting of diffuse WM disease. We present a detailed review of the conditions affecting WM that produce these neurobehavioral syndromes, and consider the pathophysiology, clinical effects, and broad significance of the effects of aging and vascular compromise on cerebral WM, in an attempt to help further the understanding, diagnosis, and treatment of these disorders.
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Affiliation(s)
- Jeremy D Schmahmann
- Ataxia Unit, Cognitive/Behavioral Neurology Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA.
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Nandigam RNK, Viswanathan A, Delgado P, Skehan ME, Smith EE, Rosand J, Greenberg SM, Dickerson BC. MR imaging detection of cerebral microbleeds: effect of susceptibility-weighted imaging, section thickness, and field strength. AJNR Am J Neuroradiol 2008; 30:338-43. [PMID: 19001544 DOI: 10.3174/ajnr.a1355] [Citation(s) in RCA: 279] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND AND PURPOSE The emergence of cerebral microbleeds (CMB) as common MR imaging findings raises the question of how MR imaging parameters influence CMB detection. To evaluate the effects of modified gradient recalled-echo (GRE) MR imaging methods, we performed an analysis of sequence, section thickness, and field strength on CMB imaging properties and detection in subjects with cerebral amyloid angiopathy (CAA), a condition associated with microhemorrhage. MATERIALS AND METHODS Multiple MR images were obtained from subjects with probable CAA, with varying sequences (GRE versus susceptibility-weighted imaging [SWI]), section thicknesses (1.2-1.5 versus 5 mm), and magnetic field strengths (1.5T versus 3T). Individual CMB were manually identified and analyzed for contrast index (lesion intensity normalized to normal-appearing white matter signal intensity) and diameter. CMB counts were compared between 1.5T thick-section GRE and thin-section SWI for 3 subjects who underwent both protocols in the same scanning session. RESULTS With other parameters constant, use of SWI, thinner sections, and a higher field strength yielded medium-to-large gains in CMB contrast index (CI; Cohen d 0.71-1.87). SWI was also associated with small increases in CMB diameter (Cohen d <0.3). Conventional thick-section GRE identified only 33% of CMB (103 of 310) seen on thin-section SWI. Lesions prospectively identified on GRE had significantly greater CI and diameter measured on the GRE image than those not prospectively identified. CONCLUSIONS The examined alternatives to conventional GRE MR imaging yield substantially improved CMB contrast and sensitivity for detection. Future studies based on these techniques will most likely yield even higher prevalence estimates for CMB.
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Affiliation(s)
- R N K Nandigam
- Hemorrhagic Stroke Research Program, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
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Unexpectedly low prevalence of intracerebral hemorrhages in sporadic cerebral amyloid angiopathy: an autopsy study. J Neurol 2008; 255:70-6. [PMID: 18202817 DOI: 10.1007/s00415-008-0674-4] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2007] [Revised: 05/14/2007] [Accepted: 06/06/2007] [Indexed: 10/22/2022]
Abstract
In a retrospective study of a consecutive autopsy series of 2060 elderly subjects (mean age 78.5 +/- 6.8 SD years), sporadic cerebral amyloid angiopathy (CAA) of various degrees was detected in 73.2% and in 98.5% of autopsy-confirmed cases of typical (plaque and tangle) Alzheimer disease (AD). Spontaneous (non-traumatic) intracerebral hemorrhages (ICH) (excluding microbleeds) were seen in 5.6% of the total cohort and in 7.2% of definite AD cases; CAA was found in 49% of brains without and in 48.7% with ICH which was not significantly different. The latter groups showed a significantly higher frequency of severe degrees of CAA than those without ICH (80.4 vs 30.9%, p < 0.001). Patients with CAA were older than those without CAA, showing a higher frequency of clinical dementia and pathologically confirmed AD, but signs of hypertension (history and/or autopsy) were seen in 41 and 33.6% of these cases, respectively, compared to 70-75% in patients with non-CAA related ICHs. CAA-related ICH much more frequently involved cerebral lobes or hemispheres, while non-CAA related lesions were more often located in basal ganglia and brainstem. The data of a lower prevalence of CAA in cases without than with ICH, but a similar prevalence of ICH with and without CAA do not support the concept that CAA represents the most evident risk factor for ICH in the aged. While severe degrees of CAA were indeed associated with ICH, the general prevalence of large ICH in this autopsy cohort was much higher in cases without CAA, probably due to other risk factors including hypertension, which was documented in around 40% of cases with CAA-related ICH. APOE epsilon3/4 and epsilon4/4 were significantly more frequent in AD (n = 163) than in age-matched controls (n = 47) and were associated with more severe degrees of CAA, but no general genotyping in ICHs with and without CAA was performed. Hence, the role of APOE in the pathogenesis of ICH with and without CAA needs further elucidation.
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Bentham P, Gray R, Sellwood E, Hills R, Crome P, Raftery J. Aspirin in Alzheimer's disease (AD2000): a randomised open-label trial. Lancet Neurol 2008; 7:41-9. [PMID: 18068522 DOI: 10.1016/s1474-4422(07)70293-4] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
BACKGROUND Cardiovascular risk factors and a history of vascular disease can increase the risk of Alzheimer's disease (AD). AD is less common in aspirin users than non-users, and there are plausible biological mechanisms whereby aspirin might slow the progression of either vascular or Alzheimer-type pathology. We assessed the benefits of aspirin in patients with AD. METHODS 310 community-resident patients who had AD and who had no potential indication or definite contraindication for aspirin were randomly assigned to receive open-label aspirin (n=156; one 75-mg enteric-coated tablet per day, to continue indefinitely) or to avoid aspirin (n=154). Primary outcome measures were cognition (assessed with the mini-mental state examination [MMSE]) and functional ability (assessed with the Bristol activities of daily living scale [BADLS]). Secondary outcomes were time to formal domiciliary or institutional care, progress of disability, behavioural symptoms, caregiver wellbeing, and care time. Patients were assessed at 12-week intervals in the first year and once each year thereafter. Analysis of the primary outcome measures was by intention to treat. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN96337233. FINDINGS Patients had a median age of 75 years; 156 patients had mild AD, 154 had moderate AD, and 18 had concomitant vascular dementia. Over the 3 years after randomisation, in patients who took aspirin, mean MMSE score was 0.10 points higher (95% CI -0.37 to 0.57; p=0.7) and mean BADLS score was 0.62 points lower (-1.37 to 0.13; p=0.11) than in patients assigned to aspirin avoidance. There were no obvious differences between the groups in any other outcome measurements. 13 (8%) patients on aspirin and two (1%) patients in the control group had bleeds that led to admission to hospital (relative risk=4.4, 95% CI 1.5-12.8; p=0.007); three (2%) patients in the aspirin group had fatal cerebral bleeds. INTERPRETATION Although aspirin is commonly used in dementia, in patients with typical AD 2 years of treatment with low-dose aspirin has no worthwhile benefit and increases the risk of serious bleeds.
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Jellinger KA, Lauda F, Attems J. Sporadic cerebral amyloid angiopathy is not a frequent cause of spontaneous brain hemorrhage. Eur J Neurol 2007; 14:923-8. [PMID: 17662016 DOI: 10.1111/j.1468-1331.2007.01880.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The retrospective study of a consecutive autopsy series of 1100 elderly subjects (mean age 78.3 +/- 6.8 SD years), revealed sporadic cerebral amyloid angiopathy (CAA) in 50.0% and in 95.7% of autopsy-confirmed cases of Alzheimer disease (AD). Apolipoprotein (APOE) epsilon 3/4 and epsilon 4/4 were significantly more frequent in AD than in controls, and were associated with more severe degrees of CAA. Spontaneous (non-traumatic) intracerebral hemorrhages (ICH) (excluding microbleeds and hemorrhagic infarctions) were seen in 5.4% and only in 3.3% of AD cases. CAA was found in 50.6% of brains without and in 42.4% with ICH, the latter showing a significantly higher frequency of severe degrees of CAA. ICH was related to CAA in 42.4%, whilst no such relation was seen in 57.6%. Patients with CAA were older, showed a higher frequency of clinical dementia and pathologically confirmed AD, but signs of hypertension (history and/or autopsy) occurred in 40%, compared with 80% in those with non-CAA-related ICHs. CAA-related ICH more frequently involved in cerebral lobes or hemispheres, whilst non-CAA-related ones were more often located in the basal ganglia and brainstem. The data of a lower prevalence of CAA in cases with than without ICH and of ICH with and without CAA do not support the concept that CAA represents the most important risk factor for ICH in the aged, probably because of other risk factors including hypertension.
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Affiliation(s)
- K A Jellinger
- Institute of Clinical Neurobiology, Kenyongasse, Vienna, Austria.
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Affiliation(s)
- David J Werring
- Stroke Research Group, Department of Headache, Brain Injury and Rehabilitation, Institute of Neurology, Queen Square, London WC1N 3BG, United Kingdom.
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