Irregular surface of carotid atherosclerotic plaque is associated with ischemic stroke: a magnetic resonance imaging study

OBJECTIVE: To determine the association between the irregularity of carotid plaque surface using multidimensional magnetic resonance imaging (MRI) of ipsilateral acute cerebral infarction (ACI) cases. METHODS: Patients with recent cerebrovascular symptoms (stroke or transient ischemic attack < 2 weeks) and atherosclerotic plaque in at least one carotid artery were diagnosed by B-mode ultrasound imaging (intima-media thickness ≥ 1.5 mm) and recruited for the present study. Irregular surface was defined when plaque surface was uneven with high and low fluctuation or plaque with surface ulceration. The irregularity of carotid plaque surface was determined on axial or oblique images alone (single-dimension) and on both axial images and oblique images (multidimensions), separately. Univariate and multivariate logistic regression analyses were performed to calculate the odds ratio (OR) and the corresponding 95% CI of the irregular plaque surface in discriminating the presence of ipsilateral ACI. RESULTS: A total of 217 included subjects (mean age: 60.7 ± 10.2 years, 149 men) were recruited and 89 (41.0%), 88 (40.6%) and 118 (54.4%) of them exhibited irregular plaque surface on axial, oblique and multidimensional MR images, respectively. The OR of irregularity of the plaque surface was determined by multidimensional MRI to be 5.88 (95% CI: 3.16–10.96, P < 0.001) in discriminating the presence of ipsilateral ACI. Following adjustment for clinical confounding factors, this association remained statistically significant (OR = 5.65, 95% CI: 2.53–12.60, P < 0.001). The analysis included further adjustment for the presence of lipid-rich necrotic core, intraplaque hemorrhage and stenosis and the results included that this association also remained statistically significant (OR = 6.08, 95% CI: 2.52–14.68, P < 0.001). CONCLUSIONS: The irregular plaque surface was determined by multidimensional MRI as an independent indicator for ipsilateral acute cerebral infarction.