Lesion Patterns on Early Diffusion-weighted Magnetic Resonance Imaging and Ischemic Stroke Subtypes

Abstract

Objective: The correct and rapid classification of the ischemic stroke subtype enables the determination of the proper treatment and a better prognosis. In this study, we investigated the association of ischemic stroke subtypes with early diffusion-weighted magnetic resonance imaging (MRI) lesion patterns. Materials and Methods: Three hundred forty-three consecutive patients with acute ischemic stroke were retrospectively evaluated. The ischemic stroke subtype for each patient was determined according to “Trial of Org 10172 in Acute Stroke Treatment Classification”. The lesion patterns in diffusion-weighted MRI in the first 24 hours of stroke were classified as single lesions, diffuse scattered lesions limited to one vascular area, and multiple territory lesions. The relationship between the diffusion-weighted MRI lesion patterns and ischemic stroke subtypes was investigated using the chi-square test. Results: The diffusion-weighted MRI lesion patterns showed significant differences among the ischemic stroke subtypes. Multiple territory lesions were more frequent in the cardioembolic and other determined causes groups compared with the large artery atherosclerosis group. Diffuse scattered lesions limited to one vascular area were more frequent in the large artery atherosclerosis, the unknown cause and the other determined causes groups than the others (p<0.01). Single lesions with a diameter smaller than 1.5 cm favored small vessel disease. None of the diffusion-weighted MRI lesion patterns was highly specific for any stroke subtype. Conclusion: Early diffusion-weighted MRI lesion distributions vary significantly among the ischemic stroke subtypes. When evaluated with other clinical findings, these data can help in the early determination of the ischemic stroke etiology.

Keywords

• ischemic stroke
• diffusion-weighted magnetic resonance imaging
• atherosclerosis
• cardioembolism
• lacunar infarction