High-risk characteristics of recurrent ischemic stroke after intensive medical management for 6-month follow-up: a histogram study on vessel wall MRI

Objective: Intensive medical management has been recommended for ischemic stroke of intracranial atherosclerosis (ICAS), but 9.4-15% probability of recurrent stroke remains an inevitable reality. The characteristics of high-risk intracranial plaque that contribute to stroke recurrence after intensive therapy are unclear.

Methods: The patients of acute ischemic stroke due to ICAS from two centers were prospectively analyzed, who underwent the 3D high-resolution head and neck vessel wall magnetic resonance imaging (hr-VW-MRI) at baseline and received intensive medical management within 90 days. The morphological features, such as minimal lumen area (MLA), and histogram parameters including entropy were assessed based on hr-VW-MR images. The recurrence of ischemic events after 6 months was defined as hyperintensity on diffusion-weighted images in the ipsilateral vascular territory. Cox regression analysis was used to calculate the hazard ratio (HR) and 95% confidence interval (CI) for recurrent events.

Results: A total of 222 patients (age 59.5 ± 12.1; males 153) were finally included, and 38 had recurrent stroke after 6 months. After adjusting the age and gender, Cox regression demonstrated that smoking (HR = 4.321; 95% CI, 1.838-10.161; p = 0.001), taking exercise (HR = 0.409; 95% CI, 0.198-0.843; p = 0.015), blood pressure management (HR = 0.180; 95% CI, 0.073-0.443; p = 0.001), MLA (HR = 0.771; 95% CI, 0.625-0.951; p = 0.015) and entropy (HR = 0.274; 95% CI, 0.130-0.576; p = 0.001) were significant predictors of recurrent ischemic stroke. However, the area under curve value of MRI parameters was significantly higher than that of traditional clinical factors (0.86 vs 0.79; p = 0.01).

Conclusions: The plaque characteristics based on hr-VW-MRI may provide complementary values over traditional clinical features in predicting ischemic recurrence for ICAS.

Key points: Question The study addresses recurrent ischemic stroke in intracranial atherosclerosis patients, identifying high-risk plaque features that contribute to recurrence despite intensive medical management. Findings Plaque features on high-resolution vessel wall magnetic resonance imaging (hr-VW-MRI), such as minimal lumen area and entropy, improve prediction of stroke recurrence over clinical factors. Clinical relevance This two-center prospective study improves patient care by using hr-VW-MRI and histogram factors like entropy to better predict stroke recurrence, allowing for more personalized treatment strategies and potentially reducing ischemic events in patients with intracranial atherosclerosis.