Topography of dilated perivascular spaces in subjects from a memory clinic cohort

and Escola de Postgrau (S.M.-R.), Universitat Autònoma de Barcelona, Edicifi U, Campus UAB, Bellaterra (Cerdanyola del Vallès), Spain.
Neurology (Impact Factor: 8.29). 04/2013; 80(17). DOI: 10.1212/WNL.0b013e31828f1876
Source: PubMed


To investigate whether the topography of dilated perivascular spaces (DPVS) corresponds with markers of particular small-vessel diseases such as cerebral amyloid angiopathy and hypertensive vasculopathy.

Patients were recruited from an ongoing single-center prospective longitudinal cohort study of patients evaluated in a memory clinic. All patients underwent structural, high-resolution MRI, and had a clinical assessment performed within 1 year of scan. DPVS were rated in basal ganglia (BG-DPVS) and white matter (WM-DPVS) on T1 sequences, using an established 4-point semiquantitative score. DPVS degree was classified as high (score > 2) or low (score ≤ 2). Independent risk factors for high degree of BG-DPVS and WM-DPVS were investigated.

Eighty-nine patients were included (mean age 72.7 ± 9.9 years, 57% female). High degree of WM-DPVS was more frequent than low degree in patients with presence of strictly lobar microbleeds (45.5% vs 28.4% of subjects). High BG-DPVS degree was associated with older age, hypertension, and higher white matter hyperintensity volumes. In multivariate analysis, increased lobar microbleed count was an independent predictor of high degree of WM-DPVS (odds ratio [OR] 1.53 [95% confidence interval (CI) 1.06-2.21], p = 0.02). By contrast, hypertension was an independent predictor of high degree of BG-DPVS (OR 9.4 [95% CI 1-85.2], p = 0.04).

The associations of WM-DPVS with lobar microbleeds and BG-DPVS with hypertension raise the possibility that the distribution of DPVS may indicate the presence of underlying small-vessel diseases such as cerebral amyloid angiopathy and hypertensive vasculopathy in patients with cognitive impairment.

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Available from: Sergi Martinez-Ramirez
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    • "Neuroimaging markers of amyloid load and CAA-related brain injury Microbleeds were identified on axial susceptibility-weighted imaging sequences by an experienced rater (S.M.R.) as described previously (Martinez-Ramirez et al., 2013). White matter hyperintensity segmentation on FLAIR MRI scans was performed using a semi-automated method (Gurol et al., 2006). "
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    • "As VRS appear along the striothalamic arteries in the BG and the penetrating arteries in the WM, it is commonly believed that VRS pathology can be differentiated spatially within the brain. Previous work suggests that severe WM-VRS may indicate cerebral amyloid angiopathy [28] [29], while BG-VRS may be more related to hypertensive arteriopathy [8]. Furthermore , it has been suggested that visible VRS on MRI of AD patients may indicate neurovascular accumulation of amyloid-and deficiencies in clearance of amyloid along the arterial perivascular space [7] [30]. "
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