5 - Structural neuroimaging

Summary

This chapter describes brain abnormalities that can be observed on magnetic resonance imaging (MRI) in patients with vascular dementia (VaD). It presents an overview of MRI abnormalities indicative of cerebrovascular disease. Computed tomography (CT) is sufficient to rule out causes of cognitive decline other than VaD or neurodegenerative types of dementia. In addition, infarcts can be observed on CT, and small-vessel disease and atrophy are appreciable to some extent. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoaraiosis (CADASIL) is a hereditary form of VaD, presenting in young patients in the absence of vascular risk factors. On imaging, diffuse white matter hyperintensities involving the U-fibers are characteristically observed, mainly in the temporal, temporopolar, and frontal regions. Quantitative methods such as diffusion tensor imaging (DTI) and magnetization transfer imaging (MTI) provide valuable new ways to assess the integrity of white matter in more detail.