Diffuse Tract Damage in CADASIL Is Correlated with Global Cognitive Impairment

Abstract

Introduction: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy ­(CADASIL) is the most common familial cerebral small vessel disease caused by notch homolog protein 3 gene mutations and is strongly associated with ischemic stroke and dementia. Patients are characterized by cognitive impairment and widespread white matter (WM) lesions. However, the relationship between WM lesions and cognitive impairment is not very clear. The aim of this study was to investigate WM microstructural abnormalities by diffusion tensor imaging (DTI) and the relationship between WM alterations and cognitive impairment in patients with CADASIL. Methods: In the present study, we evaluated WM degeneration in 18 patients with CADASIL and 18 controls by fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD), and mean diffusivity (MD) based on DTI. Results: Compared with healthy controls, patients with CADASIL showed extensive and significant reductions in FA and increased RD, AD, and MD. These alterations were distributed throughout the entire brain (mainly the inferior and superior longitudinal fasciculus, inferior fronto-occipital fasciculus, corpus callosum, internal capsule, external capsule, corona radiata, thalamic radiation, and cingulum). Furthermore, these WM microstructural alterations were significantly correlated with cognitive scores and stroke scale scores. Conclusion: Patients with ­CADASIL showed widespread WM abnormalities, and WM microstructural integrity and cognitive impairment were significantly correlated. Our results indicated that damage to WM tracts plays an important role in cognitive impairment in CADASIL.