Trial of ORG 10172 in Acute Stroke Treatment (TOAST) Classification and Vascular Territory of Ischemic Stroke Lesions Diagnosed by Diffusion‐Weighted Imaging

Abstract

BackgroundThe association between the location and the mechanism of a stroke lesion remains unclear. A diffusion‐weighted imaging study may help resolve this lack of clarity.Methods and ResultsWe studied a consecutive series of 2702 acute ischemic stroke patients whose stroke lesions were confirmed by diffusion‐weighted imaging and who underwent a thorough etiological investigation. The vascular territory in which an ischemic lesion was situated was identified using standard anatomic maps of the dominant arterial territories. Stroke subtype was based on the Trial of ORG 10172 in Acute Stroke Treatment, or TOAST, classification. Large‐artery atherosclerosis (37.3%) was the most common stroke subtype, and middle cerebral artery (49.6%) was the most frequently involved territory. Large‐artery atherosclerosis was the most common subtype for anterior cerebral, middle cerebral, vertebral, and anterior and posterior inferior cerebellar artery territory infarctions. Small vessel occlusion was the leading subtype in basilar and posterior cerebral artery territories. Cardioembolism was the leading cause in superior cerebellar artery territory. Compared with carotid territory stroke, vertebrobasilar territory stroke was more likely to be caused by small vessel occlusion (21.4% versus 30.1%, P<0.001) and less likely to be caused by cardioembolism (23.2% versus 13.8%, P<0.001). Multiple‐vascular‐territory infarction was frequently caused by cardioembolism (44.2%) in carotid territory and by large‐artery atherosclerosis (52.1%) in vertebrobasilar territory.ConclusionsInformation on vascular territory of a stroke lesion may be helpful in timely investigation and accurate diagnosis of stroke etiology.

Stroke Lesions in a Large Upper Limb Rehabilitation Trial Cohort Rarely Match Lesions in Common Preclinical Models

“…Most of the strokes in ICARE were subcortical, and there was approximately half the incidence of MCA stroke reported in population-based studies (31% vs. 45–65%) 20–22 . ICARE participants had a much higher incidence of ischemic stroke in the anterior choroidal artery territory (30% vs. 2–8%) 64–66 and the pons (23% vs. 5–11%) 20,21,65,67 , which corroborates reports that strokes causing motor impairment commonly overlap the CST 26,27 . Note that there is a large literature of prior studies not cited above assessing lesion volumes in general stroke populations 32,68–72 , but methodological concerns hindered proper comparison to our patient cohort.…”

Acute Ischemic Stroke Management Review for the Hospitalist

“…A recent analysis of an acute ischemic stroke confirmed by diffusion-weighted imaging (DWI) in a large Asian cohort utilizing TOAST classification found large-artery atherosclerosis to be the most common stroke subtype with the middle cerebral artery (MCA) territory most frequently affected (15). However, a non-Asian population determined cardioembolic stroke to be the most common subtype (16).…”

Perioperative Stroke

“…Although the Acute Stroke Treatment classification system is useful to differentiate the etiology of ischemic stroke in the nonoperative setting [21], the lack of robust studies and infrequent occurrence prevent the same level of granularity in defining the etiologies of perioperative stroke. The majority of perioperative strokes are cortical infarcts located in the MCA territory [22].…”