MRI Intensity Tissues Normalisation for Longitudinal Surface Based Analysis of the WM/GM Contrast, Application to Alzheimers Disease

Vincent Dor¹, Jurgen Fripp¹, Pierrick Bourgeat¹, Oscar Acosta^1,2, Olivier Salvado¹

MR imaging has been widely used to highlight the brain changes occurring in neurodegenerative diseases by comparing affected patients to healthy individuals. However, only few studies focus on contrast changes between gray matter (GM) and white matter (WM). To our knowledge, no longitudinal study of tissue intensities has been reported. We hypothesize that tissue alteration as measured by WM/GM could provide insights into the etiology of Alzheimers disease (AD). We investigate the longitudinal evolution of the contrast using a new tissue normalisation method. The MRI intensity normalisation enable to measure significant change in contrast between AD patient and healthy elder.