Dilation of Virchow-Robin spaces in CADASIL

To precise the severity of dilated Virchow-Robin spaces (VRS) in CADASIL patients and to determine their correlation with clinical presentation and other abnormalities on cerebral Magnetic Resonance Imaging (MRI). Dilated VRS were previously associated with aging, hypertension, dementia, epilepsy or migraine. We already reported increased frequency of enlarged VRS in CADASIL patients when compared with family members without the affected haplotype. We analysed clinical and MRI data from 50 CADASIL patients collected prospectively in our center. The presence of dilated VRS was assessed in the subcortical white matter of temporal lobes, the centrum semi-ovale and the basal ganglia. Their severity in each region was evaluated according to the scale proposed by Heier. We compared the clinical data, the severity of white matter abnormalities and the presence of microbleeds in patients with and without dilated VRS. Seventy-eight percent of patients in our series had dilated VRS, mostly located in the lentiform nuclei (94%) and subcortical white matter of the temporal lobes (66%). The severity of these lesions was variable but not correlated neither to the extent of white matter abnormalities nor to the clinical presentation in our patients. Only the age was found to be related to the extent of dilated VRS. Dilated VRS are frequent in CADASIL and mostly located in the temporal white matter and basal ganglia. The dilation of perivascular spaces does not seem to be directly related to the occurrence of ischemic or hemorrhagic lesions in CADASIL. In contrast, the relation with age suggests that either aging, progression of vascular wall alterations during the course of the disease, or both of these processes can favour the extension of VRS in CADASIL.