Purpose: There is still insufficient evidence for predicting stroke risk in patients with mild carotid atherosclerotic stenosis. This study aimed to explore the association between carotid intraplaque neovascularization (IPN) in mild stenosis and ischemic stroke, using contrast-enhanced ultrasound (CEUS) imaging.
Methods: This retrospective observational study included 369 patients from July 2021 to March 2022. These patients were categorized as symptomatic or asymptomatic based on their recent history of ipsilateral ischemic stroke. Initial parameters of carotid plaques, such as IPN grading and contrast enhancement index, were assessed using B-mode ultrasonography and CEUS. The follow-up period lasted 12 months or until a newly-developed ischemic stroke occurred. Logistic regression models and Cox proportional-hazards regression models were employed to explore the associations between ultrasonic parameters and the incidence of recent and future ischemic strokes.
Results: In patients with mild stenosis, both increasing age and grade 2 carotid IPN were significant predictors of recent primary ischemic stroke. Furthermore, grade 2 carotid IPN independently predicted future ischemic strokes in both symptomatic and asymptomatic patients.
Conclusion: This study demonstrated that carotid IPN as detected by CEUS imaging holds potential as a useful non-invasive biomarker for predicting recent and future ischemic strokes in patients with mild carotid stenosis.
Keywords: Carotid artery diseases; Contrast-enhanced ultrasound; Intraplaque neovascularization; Ischemic stroke; Vulnerable plaque.