A multimodal imaging study on spatial pattern of cerebral perfusion change caused by symptomatic unilateral carotid artery stenosis

Abstract

Objective To investigate the spatial pattern of cerebral perfusion decrease resulting from symptomatic unilateral carotid artery stenosis and to assess the relationship between degrees of stenosis and cerebral blood flow (CBF). Methods CT angiography (CTA) and arterial spin labeling (ASL) MRI cerebral perfusion were performed in 22 patients with symptomatic unilateral carotid artery stenosis. Diagnosis of carotid artery stenosis and measurement of stenosis degrees was performed by using CTA; cerebral perfusion was determined by ASL. Voxel-based analysis (VBA) were applied to observe perfusion changes in patients with mild stenosis and moderate to severe stenosis, and spatial pattern of cerebral perfusion changes caused by carotid artery stenosis. Analysis based on region of interest (ROI) was used to explore the relationship between degrees of stenosis and CBF. Results Twenty-two patients with symptomatic unilateral carotid artery stenosis (13 in the left side and 9 in the right) included 13 cases with mild stenosis and 9 cases with moderate to severe stenosis. Compared to those with mild stenosis, patients with moderate to severe stenosis showed reduced CBF in bilateral (especially in the affected side) parietal lobes ( t = - 2.382, P = 0.014), frontal lobes ( t = - 2.354, P = 0.015) and centrum semiovale ( t = - 2.283, P = 0.017), and was basically located in bilateral cerebral watershed area. Furthermore, perfusion in these areas was negatively correlated with the degree of stenosis ( r = - 0.479, P = 0.024). Conclusions Symptomatic unilateral carotid artery stenosis may result in cerebral perfusion decreases in bilateral (particularly in the affected side) watershed area and cerebral blood flow is negatively correlated with the degree of stenosis. DOI: 10.3969/j.issn.1672-6731.2015.02.006