Determinants of arterial spin labeling parameters and its association with cerebral small vessel disease and diagnostic groups

Abstract

AbstractBackgroundCerebral small vessel disease (SVD) may alter cerebral blood flow (CBF) leading to brain changes and hence cognitive impairment and dementia in elderly. CBF and spatial coefficient of variation (sCoV) can be measured quantitatively by Arterial Spin Labelling (ASL). CBF and sCoV have been related to age and systemic vascular risk factors. The relation of CBF and sCoV with location and severity of SVD and etiologic subtypes of cognitive impairment and dementia have not been explored in detail. We aim to investigate the association of demographic, vascular risk factors, location and severity of SVD with ASL parameters. We further investigate the association of ASL parameters with etiologic subtypes of cognitive impairment and dementia in a memory clinic population.MethodWe included 390 subjects (median: 73 11years, women = 52.3%) from an ongoing memory‐clinic based case‐control study. Patients were classified as no cognitive impairment, cognitive impairment no dementia (CIND), vascular CIND (VCIND) and dementia [Alzheimer’s disease (AD) and Vascular Dementia (VaD)]. Cerebral microbleeds (CMBs) and lacunes were categorized into strictly lobar, strictly deep and mixed‐location; ePVS into centrum semiovale and basal ganglia. Total and region‐specific white matter hyperintensities (WMH) volumes were automatically segmented using a validated pipeline. sCoV and CBF were analyzed with ExploreASL from 2D‐EPI pseudo‐continuous ASL images.ResultIncreasing age, male sex, hypertension, hyperlipidemia, history of heart disease and smoking were associated with CBF and sCoV. Increasing numbers of lacunes and CMBs were associated with reduced CBF and increased sCoV. Location‐specific analysis showed mixed‐location lacunes and CMBs were associated with hypoperfusion. Total WMH volume was associated with associated with increased sCoV. Region specific analysis with anterior and posterior WMH volumes showed similar results. No association was observed between ePVS and ASL parameters. Increased sCoV was associated with the diagnosis of VCIND, AD and VaD.ConclusionIncreased sCoV in ASL is associated with SVD, cognitive impairment and dementia, suggesting that SVD may induce brain changes via vascular insufficiency. Thus future research aimed to elucidate the pathophysiology of SVD and vascular insufficiency in elderly may help in developing prevention and treatment strategies.