Yu I, Bang OY, Chung JW, et al. - In patients with large vessel occlusion and small core, researchers explored the connection between serial changes in collateral status and infarct volume defined on diffusion-weighted imaging (DWI). Participants in the study were consecutive patients who were candidates for endovascular treatment (Alberta Stroke Program Early CT Score [ASPECTS] of ≥ 6 points) and who had both pretreatment multiphasic computed tomography angiography (mCTA) and multimodal MRI. The mCTA collateral grade was the only factor independently associated with the DWI lesion volume after adjusting for the initial stroke severity, ASPECTS, time to DWI, and mismatch volume. An excellent correlation was observed between the mCTA- and MRI-based collateral grades, suggesting a persistence of the collateral status during the hyperacute stroke phase. The collateral adequacy assessed by mCTA is the only predictor of eventual DWI lesion volume prior to endovascular treatment. Further evaluation is required for the added value of collateral evaluation in early ischemic modifications and large vessel occlusion for decision making concerning more aggressive revascularizations.