Association of MRI-Visible Perivascular Spaces with Early White Matter Injury
Arturo Toro1, Frances Rodriguez Lara2, Adlin Pinheiro2,3
1From the Boston University Chobanian & Avedisian School of Medicine (A.T., F.R.L., A.P., S.D.), Boston, Massachusetts artoro@bu.edu.
Background And Purpose:
MRI-visible perivascular spaces (PVS) are considered markers of cerebral small vessel disease (CSVD) and may reflect dysfunction of brain perivascular drainage. WM integrity assessed with DTI provides a sensitive assessment of early brain injury, related vascular risk factors, and risk of stroke and dementia. We investigated the relationship between PVS and WM integrity in community-dwelling participants.
Materials And Methods:
Framingham Heart Study (FHS) participants with brain MRI, PVS ratings, and DTI measures were included. PVS were rated in the basal ganglia (BG) and centrum semiovale (CS) and categorized into grades I-IV based on counts. We related PVS burden to global DTI measures (free water fraction [FW], fractional anisotropy [FA], peak skeletonized mean diffusivity [PSMD]), diffusion along perivascular spaces (DTI-ALPS), and voxel-based measures using multivariable linear regression analyses.
Results:
Among 3077 participants (57.2 mean age; 53% women), 7% had high-burden PVS in the BG, and 13% had high burden in the CS. High PVS burden in either or both regions was associated with higher global FW, PSMD, lower global FA, and lower DTI-ALPS index in fully adjusted models (P < .001). Voxel analyses revealed significant associations between high PVS burden in both regions and FW involving ascending, descending, interhemispheric, and intrahemispheric tracts (P < .0001) but not with FA.
Conclusions:
PVS burden was associated with early signs of global WM injury after adjustment for vascular risk factors, suggesting that high PVS burden may represent early brain injury related to CSVD or impaired perivascular function.
Insights
High perivascular spaces (PVS) burden is linked to white matter (WM) injury in community-dwelling adults. This finding suggests PVS may indicate early brain damage from cerebral small vessel disease (CSVD) or impaired drainage.
Area of Science:
- Neurology
- Radiology
- Neuroimaging
Background:
- Perivascular spaces (PVS) visible on MRI are markers of cerebral small vessel disease (CSVD).
- PVS dysfunction may indicate impaired brain perivascular drainage.
- White matter (WM) integrity, assessed by diffusion tensor imaging (DTI), reflects early brain injury and vascular risk.
Purpose of the Study:
- To investigate the relationship between PVS burden and WM integrity.
- To assess PVS as a potential marker for early brain injury in community-dwelling individuals.
Main Methods:
- Utilized data from 3077 Framingham Heart Study participants with brain MRI and DTI measures.
- Rated PVS burden in basal ganglia (BG) and centrum semiovale (CS) into grades I-IV.
- Employed multivariable linear regression to relate PVS burden to global DTI metrics (FW, FA, PSMD) and DTI-ALPS.
Main Results:
- High PVS burden in BG or CS was associated with increased global free water (FW) and PSMD.
- High PVS burden correlated with decreased global fractional anisotropy (FA) and DTI-ALPS index (P < .001).
- Voxel analyses showed high PVS burden associated with FW in major white matter tracts (P < .0001).
Conclusions:
- PVS burden is associated with early global WM injury, independent of vascular risk factors.
- Elevated PVS burden may signify early brain injury related to CSVD or impaired perivascular function.
