Étude des liens entre les mesures quantitatives de la vascularisation cérébrale, les fonctions cognitives et la neuropathologie dans la maladie d’Alzheimer

Introduction: With the aging of the world population, it is estimated that approximately 78 million people worldwide will be affected by a major neurocognitive disorder (TNC) in 2030. However, the etiology of Alzheimer's disease (AD), the most common form of major TNC, remains unclear. Given the growing body of evidence supporting a relationship between vascular factors and AD, the present project explored the cerebrovascular component as a potential pathophysiological mechanism of this disease. Objectives: Explore the relationship between 1) the diameters of the posterior cerebral arteries, 2nd segment (ACP2) and of the anterior choroidal arteries (AchA) and the Clinical Dementia Rating Scale – Sum of Boxes (CDR-SB) and 2) the diameters and the volumes of cerebral arteries and i) cognition; ii) AD neuropathology, such as hippocampal atrophy, cerebral atrophy, and amyloid burden; iii) cognitive decline. Methodology: Participants were selected from the OASIS-3 database. Intracranial arteries were assessed by time-of-flight magnetic resonance angiography (TOF-MRA) and their quantitative measurements were calculated using a newly developed artificial intelligence algorithm. Cognitive status was assessed by MMSE (Mini-Mental State Examination), CDR, and several neuropsychological tests, including Logical Memory and Trail Making tests. Amyloid burden was visualized by amyloid PET with contrast and quantified using the Centiloid scale. Brain and hippocampal volumes were assessed by T1-weighted MRI. Results: The primary results showed that ACP2 and AchA diameters were not significantly correlated with CDR-SB scores. For secondary outcomes, AchA had the most associations (nonlinear and negative) with cognitive functions and AD markers. Conversely, the anterior cerebral arteries (ACA), the basilar artery, and the posterior cerebral arteries, 1st segment (ACP1) had very little relationship with cognition. Among the statistically significant secondary results, the correlations were of low intensity. Conclusion: Using TOF-MRA imaging and artificial intelligence technology, we were able to calculate the quantitative measurements of the intracranial arteries and thus assess their association with certain AD elements. Future research should be conducted to overcome the limitations of the present study in order to confirm these findings.

Name thesis:degree_name

M. Sc.

Level thesis:degree_level

Maîtrise

Discipline thesis:degree_discipline

Gérontologie

Grantor dc:publisher

Université de Sherbrooke

Year dc:date.issued

2022

Author dc:creator

• Ni, Vivian

Advisors dc:contributor.advisor

• Bocti, Christian
• Whittingstall, Kevin

• Maladie d’Alzheimer
• TOF-MRA
• Cercle de Willis
• Artères choroïdiennes antérieures
• Fonctions cognitives
• Fardeau amyloïde
• Hippocampe
• Volume cérébral
• Alzheimer’s disease
• Circle of Willis
• Anterior choroidal arteries
• Cognitive functions
• Amyloid burden
• Hippocampus
• Cerebral volume

Licence dc:rights.uri

• http://creativecommons.org/licenses/by-nc-nd/2.5/ca/

Language dc:language.iso

fr

Handle dc:identifier.uri

http://hdl.handle.net/11143/19503

OAI identifier oai:identifier

oai:usherbrooke.scholaris.ca:11143/19503