Hippocampus Study: Comparative Effect of Donepezil 10mg/d and Placebo on Clinical and Radiological Markers

The development of a new automated method of measurement of the volume of the hippocampus allows confirming these results in patients presenting with pre-dementia Alzheimer's Disease (AD), treated with donepezil in order to verify if this product is capable of stopping the speed of the atrophy of the hippocampus in patients and more specifically in those who will evolve to AD, compared to a placebo. This method is a semi automatic segmentation of the hippocampus from MRI, made by competitive region growing. It was developed at the cognitive neurosciences and MRI laboratory in Pitié-Salpêtrière hospital. This method was validated on healthy subjects and Alzheimer's disease patients by comparison with manual segmentation. Neuropsychological tests will be realized in order to supervise the clinical evolution of the patients and to correlate these results to the progression of the atrophy of the hippocampus.