Classification of sMRI for AD Diagnosis with Convolutional Neuronal Networks: A Pilot 2-D+ε Study on ADNI

In interactive health care systems, Convolutional Neural Networks (CNN) are starting to have their applications, e.g. the classification of structural Magnetic Resonance Imaging (sMRI) scans for Alzheimer's disease Computer-Aided Diagnosis (CAD). In this paper we focus on the hippocampus morphology which is known to be affected in relation with the progress of the illness. We use a subset of the ADNI (Alzheimer's Disease Neuroimaging Initiative) database to classify images belonging to Alzheimer's disease (AD), mild cognitive impairment (MCI) and normal control (NC) subjects. As the number of images in such studies is rather limited regarding the needs of CNN, we propose a data augmentation strategy adapted to the specificity of sMRI scans. We also propose a 2-D+epsilon approach, where only a very limited amount of consecutive slices are used for training and classification. The tests conducted on only one - saggital - projection show that this approach provides good classification accuracies: AD/NC 82.8% MCI/NC 66% AD/MCI 62.5% that are promising for integration of this 2-D+epsilon strategy in more complex multi-projection and multi-modal schemes.