Diffusion-weighted imaging as predictor of acute ischemic stroke etiology

Abstract

Background: Topographic patterns may correlate with causes of ischemic stroke. Objective: To investigate the association between diffusion-weighted imaging (DWI) and Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification. Methods: We included 1019 ischemic stroke patients. DWI were classified as: i) negative; ii) DWI single lesion (cortico-subcortical, cortical, subcortical ≥20 mm, or subcortical <20 mm); iii) scattered lesions in one territory (small scattered lesions or confluent with additional lesions); and iv) multiple lesions (multiple unilateral anterior circulation [MAC], multiple posterior circulation [MPC], multiple bilateral anterior circulation [MBAC], and multiple anterior and posterior circulations [MAP]). Results: There was a relationship between DWI patterns and TOAST classification (p<0.001). Large artery atherosclerosis was associated with small, scattered lesions in one vascular territory (Odds Ratio [OR] 4.22, 95% confidence interval [95%CI] 2.61–6.8), MPC (OR 3.52; 95%CI 1.54–8.03), and subcortical lesions <20 mm (OR 3.47; 95%CI 1.76–6.85). Cardioembolic strokes correlated with MAP (OR 4.3; 95%CI 1.64–11.2), cortico-subcortical lesions (OR 3.24; 95%CI 1.9–5.5) and negative DWI (OR 2.46; 95%CI 1.1–5.49). Cryptogenic strokes correlated with negative DWI (OR 4.1; 95%CI 1,84–8.69), cortical strokes (OR 3.3; 95%CI 1.25–8.8), MAP (OR 3.33; 95%CI 1.25–8.81) and subcortical lesion ≥20 mm (OR 2.44; 95%CI 1,04–5.73). Lacunar strokes correlated with subcortical lesions diameter <20 mm (OR 42.9; 95%CI 22.7–81.1) and negative DWI (OR 8.87; 95%CI 4.03–19.5). Finally, MBAC (OR 9.25; 95%CI 1.12–76.2), MAP (OR 5.54; 95%CI 1.94–15.1), and MPC (OR 3.61; 95%CI 1.5–8.7) correlated with stroke of other etiologies. Conclusions: A relationship exists between DWI and stroke subtype.

Magnetic Resonance Imaging Assists With Determining Etiology After Transient Ischemic Attack or Minor Stroke

“…By assisting with a diagnosis of SVD, MRI DWI could improve secondary stroke prevention by focusing management on addressing vascular risk factors and potentially avoid additional tests that will not likely change management. Prior studies have demonstrated that infarct topography is useful to identify an ischemic etiology, 7 , 8 , 9 , 10 , 11 , 12 while the present study demonstrates the potential magnitude of using this tool to reduce the rate of cryptogenic etiology in the TIA or minor stroke population.…”

“…This result is consistent with a prospective study of patients with acute ischemic stroke, where a single subcortical lesion was strongly associated with increased odds of lacunar stroke diagnosis. 12 Although SVD can be diagnosed clinically on the basis of presence of symptoms suggestive of a classic lacunar syndrome, SVD diagnosis also depends on brain imaging. Visualizing a single, small, subcortical lesion on DWI likely increases the clinician's confidence of attributing the etiology to SVD, and, conversely, identifying multiple infarcts would decrease the attribution to small‐vessel etiology.…”

“…The rate of cryptogenic stroke in the current era is 30% to 35% 5 , 6 ; therefore, it remains imperative to find additional methods of identifying stroke etiology to tailor therapies appropriately. Several studies have demonstrated that infarct topography on MRI can assist with determining stroke etiology, 7 , 8 , 9 , 10 , 11 , 12 but how and to what extent DWI positivity influences etiology determination in a clinical context has not yet been well characterized. This is especially true in patients with suspected TIA or minor stroke.…”

Acute ischemic stroke in elderly population with and without left atrial appendage thrombus: what are the differences in brain magnetic resonance imaging findings?

“…Nghiên cứu của chúng tôi cũng ghi nhận tỷ lệ nhồi máu não vùng vỏ-dưới vỏ cao hơn ở nhóm có huyết khối tiểu nhĩ trái so với nhóm không có. Kết quả này cũng đã được ghi nhận trong nghiên cứu của Alejandro và cộng sự với cơ chế chính xác chưa được hiểu rõ mặc dù có thể liên quan đến vị trí tắc động mạch và mức độ lan rộng của tổn thương não do huyết khối từ tim [16].…”

Applications of Magnetic Resonance Imaging in Stroke for Multidimensional Assessment

“…In addition, DWI can differentiate between ischemic and hemorrhagic subtypes of stroke since hemorrhagic stroke often does not exhibit diffusion-restricted areas on DWI images (Brunser et al, 2022) (Yoo et al, 2011). The grayscale values and diffusion indices of DWI images can be used to assess functional prognosis of stroke patients (Bang et al, 2005).…”