Supplementary Material for: Exploring the relationship between lesion morphology and pathogenesis in acute small subcortical infarction

Introduction Acute small subcortical infarctions (SSIs) result from occlusions of small penetrating arteries, and the underlying pathological factors can have different clinical implications. The objective of this study was to assess the clinical relevance of acute SSIs based on their sizes and morphologies. Methods This retrospective case-control study analyzed clinical and imaging data of stroke patients with acute SSIs in penetrating artery territories who underwent MRI within 5 days of stroke onset, registered between 2016 and 2020. We categorized these patients into three groups based on size and morphology: diameter 50% (aOR, 3.8; 95% CI, 2.1–7.0) than a diameter of <20mm. Moreover, SSIs with a diameter of ≥20mm was found to be associated with an increased risk of END compared to that with a diameter of <20mm (aOR, 2.9; 95% CI, 1.7–5.2). Conclusion Our study suggests that the sizes and morphologies of acute SSIs may indicate different underlying pathologies and be linked to diverse clinical outcomes. Our findings also challenge the current imaging criteria for embolic stroke of undetermined source, as we did not find a link between large subcortical infarction and cardioembolic stroke.