Publications by authors named "Marianne Chapleau"

Florbetaben (FBB) is a radiopharmaceutical approved by the FDA and EMA in 2014 for the positron emission tomography (PET) imaging of brain amyloid deposition in patients with cognitive impairment who are being evaluated for Alzheimer's disease (AD) or other causes of cognitive decline. Initially, the clinical adoption of FBB PET faced significant barriers, including reimbursement challenges and uncertainties regarding its integration into diagnostic clinical practice. This review examines the progress made in overcoming these obstacles and describes the concurrent evolution of the diagnostic landscape.

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Background: Posterior Cortical Atrophy (PCA) is a clinical syndrome characterized by progressive visuospatial and visuoperceptual impairment. As the neurodegenerative disease progresses, patients lose independent functioning due to the worsening of initial symptoms and development of symptoms in other cognitive domains. The timeline of clinical progression is variable across patients, and the field currently lacks robust methods for prognostication.

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Article Synopsis
  • Posterior Cortical Atrophy (PCA) is a syndrome that causes gradual problems with visual processing and spatial awareness, leading to decreased independence as symptoms worsen over time; predicting the disease's progression can be challenging due to individual variability.!* -
  • The study involved recruiting PCA patients from a specialized program and using MRI scans to measure cortical thickness, which was then correlated with clinical assessments of cognitive decline over time, focusing on the CDR Sum-of-Boxes score.!* -
  • Analysis of data from 34 PCA patients revealed significant cortical atrophy in posterior brain regions, especially in areas responsible for visual processing, indicating that baseline cortical atrophy can be a useful predictor of future cognitive decline in PCA patients.!*
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Background And Objectives: Cavum septum pellucidum (CSP) is a common but nonspecific MRI finding in individuals with prior head trauma. The type and extent of head trauma related to CSP, CSP features specific to head trauma, and the impact of brain atrophy on CSP are unknown. We evaluated CSP cross-sectionally and longitudinally in healthy and clinically impaired older adults who underwent detailed lifetime head trauma characterization.

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The accumulation of tau abnormality in sporadic Alzheimer's disease is believed typically to follow neuropathologically defined Braak staging. Recent PET evidence challenges this belief, however, as accumulation patterns for tau appear heterogeneous among individuals with varying clinical expressions of Alzheimer's disease. We, therefore, sought a better understanding of the spatial distribution of tau in the preclinical and clinical phases of sporadic Alzheimer's disease and its association with cognitive decline.

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Background: Posterior cortical atrophy is a rare syndrome characterised by early, prominent, and progressive impairment in visuoperceptual and visuospatial processing. The disorder has been associated with underlying neuropathological features of Alzheimer's disease, but large-scale biomarker and neuropathological studies are scarce. We aimed to describe demographic, clinical, biomarker, and neuropathological correlates of posterior cortical atrophy in a large international cohort.

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Posterior cortical atrophy (PCA) is a rare neurodegenerative condition characterized by progressive visual and visuospatial dysfunction. The consensus criteria state that patients should present "relatively spared behavior and personality" in early stages. However, limited research has focused on these symptoms in PCA.

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The spread of tau abnormality in sporadic Alzheimer's disease is believed typically to follow neuropathologically defined Braak staging. Recent positron emission tomography (PET) evidence challenges this belief, however, as spreading patterns for tau appear heterogenous among individuals with varying clinical expression of Alzheimer's disease. We therefore sought better understanding of the spatial distribution of tau in the preclinical and clinical phases of sporadic Alzheimer's disease and its association with cognitive decline.

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Introduction: Posterior Cortical Atrophy (PCA) is a neurodegenerative disorder characterized by impairment of higher-order visual processing in the setting of progressive atrophy of the parietal and occipital lobes. The underlying pathology is variable but most commonly Alzheimer's disease. The majority of individuals develop symptoms before 65 years of age; however, delayed diagnosis is common due to misattribution of symptoms to ocular rather than cortical pathology.

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Purpose Of Review: The study aims to provide a summary of recent developments for diagnosing and managing posterior cortical atrophy (PCA). We present current efforts to improve PCA characterisation and recommendations regarding use of clinical, neuropsychological and biomarker methods in PCA diagnosis and management and highlight current knowledge gaps.

Recent Findings: Recent multi-centre consensus recommendations provide PCA criteria with implications for different management strategies (e.

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Background: Mindfulness, defined as nonjudgmental awareness of the present moment, has been associated with an array of mental and physical health benefits. Mindfulness may also represent a protective factor for Alzheimer's disease (AD). Here, we tested the potential protective effect of trait mindfulness on cognitive decline and AD pathology in older adults at risk for AD dementia.

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Imaging of amyloid deposition using PET has been available in research studies for 2 decades and has been approved for clinical use by the U.S. Food and Drug Administration, the European Medicines Agency, and other regulatory agencies around the world.

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Article Synopsis
  • The study investigates how semantic variant primary progressive aphasia (svPPA) affects hippocampal volume and shape compared to Alzheimer's disease (AD) and healthy controls.
  • Using MRI scans from 22 svPPA patients, 99 AD patients, and 92 controls, researchers measured hippocampal volume and shape changes.
  • Results revealed similar patterns of hippocampal atrophy and deformation in svPPA and AD, indicating significant morphological changes that should be recognized in svPPA diagnoses.
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The goal of the study was to determine whether the semantic variant of primary progressive aphasia (svPPA) affects the intrinsic connectivity network anchored to left and right anterior hippocampus, but spares the posterior hippocampus. A resting-state functional connectivity MRI (rs-fcMRI) study was conducted in a group of patients with svPPA and in controls, using a seed-to-voxel approach. In comparison to controls, massively reduced connectivity was found in the anterior hippocampus, mainly the left one, for svPPA patients but not in the left or right posterior hippocampus.

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Patients with Alzheimer's disease (AD) and semantic variant primary progressive aphasia (svPPA) can present with similar language impairments, mainly in naming. It has been hypothesized that these deficits are associated with different brain mechanisms in each disease, but no previous study has used a network approach to explore this hypothesis. The aim of this study was to compare resting-state functional magnetic resonance imaging (rs-fMRI) language network in AD, svPPA patients, and cognitively unimpaired elderly adults (CTRL).

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High angular resolution diffusion imaging (HARDI)-based tractography has been increasingly used in longitudinal studies on white matter macro- and micro-structural changes in the language network during language acquisition and in language impairments. However, test-retest reliability measurements are essential to ascertain that the longitudinal variations observed are not related to data processing. The aims of this study were to determine the reproducibility of the reconstruction of major white matter fiber bundles of the language network using anatomically constrained probabilistic tractography with constrained spherical deconvolution based on HARDI data, as well as to assess the test-retest reliability of diffusion measures extracted along them.

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Cognitive and computational models of reading aloud agree on the existence of two procedures for reading. Pseudowords (e.g.

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Article Synopsis
  • The study explored the patterns of gray matter atrophy in Alzheimer's disease (AD) and semantic dementia (SD) through a meta-analysis of voxel-based morphometry (VBM) studies, revealing distinct episodic memory profiles despite both conditions exhibiting hippocampal atrophy.
  • Both AD and SD showed bilateral hippocampal atrophy; however, in SD, the atrophy was mainly in the anterior hippocampus, while in AD, both anterior and posterior portions were affected, with more severe atrophy in areas like the posterior hippocampus and precuneus for AD patients.
  • The findings support the idea that episodic memory deficits in AD are linked to damage in the posterior hippocampus and associated brain regions, whereas the relative sparing of this area
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