Validation of an Magnetic Resonance Imaging Acquisition and Review Protocol for Alzheimer's Disease and Related Disorders

Magnetic resonance imaging (MRI) of the brain allows for the identification of structural lesions typical of Alzheimer's disease (AD), the main cause of dementia. However, to have a clinical impact, it is imperative that acquisition and reporting of this MRI-based evidence be standardized, ensuring the highest possible reliability and reproducibility. Our objective was to validate a systematic radiological MRI acquisition and review process in the context of AD. We included 100 individuals with a suspicion of dementia due to AD for whom MRI were acquired using our proposed protocol of clinically achievable acquisitions and used a unified reading grid to gather semi-quantitative evidence guiding diagnostic. MRIs were read by 3 raters with different experience levels. Interrater reliability was measured using Cohen's kappa statistic. Interrater reliability average for lesions occupying space, hemorrhage, or ischemia, was respectively 0.754, 0.715, and 0.501. Average reliability of white matter hyperintensity burden (Fazekas), global cortical atrophy, and temporal lobe atrophy (Scheltens) scales was 0.687, 0.473, and 0.621 (right)/0.599 (left), respectively. The kappas for regional cortical atrophy (frontal, parietal, occipital, temporal, and posterior cingulum) varied from 0.281–0.678. The average MRI reading time varied between 1.43-5.22 minutes. The presence of space occupying lesions, hemorrhagic or ischemic phenomena, and radiological scales have a good interrater reproducibility in MRI. Coupled with standardized acquisitions, such a protocol should be used when evaluating possible dementias, especially those due to probable AD. L'imagerie par résonance magnétique (IRM) du cerveau permet d'identifier les lésions structurales typiques de la maladie d’Alzheimer, la cause principale de démence. Néanmoins, pour avoir un impact clinique, il est essentiel que l'acquisition et le compte rendu des données obtenues par IRM soient normalisés, afin d'assurer les plus hauts niveaux possible de fiabilité et de reproductibilité. Notre objectif était de valider une acquisition systématique d’IRM radiologique et d'analyser ce processus dans le contexte de la maladie d’Alzheimer. Cent individus chez lesquels une démence est soupçonnée en raison de la maladie d’Alzheimer ont été inclus dans l’étude. Les données d’IRM ont été acquises grâce au protocole proposé d'acquisitions cliniquement réalisables, et une grille de lecture commune a été utilisée pour rassembler les donn