Related Experiment Video
Updated: Aug 14, 2025
A Fibrin-Enriched and tPA-Sensitive Photothrombotic Stroke Model
Published on: June 4, 2021
Brush sign and collateral supply as potential markers of large infarct growth after successful thrombectomy
Alexandre Bani-Sadr1,2, Dylan Pavie3, Laura Mechtouff4,5
1Department of Neuroradiology, East Group Hospital, Hospices Civils de Lyon. 59 Bd Pinel, 69500, Bron, France. apbanisadr@gmail.com.
Objectives:
To investigate the relationships between brush sign and cerebral collateral status on infarct growth after successful thrombectomy.
Methods:
HIBISCUS-STROKE cohort includes acute ischemic stroke patients treated with thrombectomy after MRI triage and undergoing a day-6 MRI including FLAIR images to quantify final infarct volume (FIV). Successful reperfusion was defined as a modified thrombolysis in cerebral infarction score ≥ 2B. Infarct growth was calculated by subtracting FIV from baseline ischemic core after co-registration and considered large (LIG) when > 11.6 mL. Brush sign was assessed on T2*-weighted-imaging and collaterals were assessed using the hypoperfusion intensity ratio, which is the volume of Time-To-Tmax (Tmax) ≥ 10 s divided by the volume of Tmax ≥ 6 s. Good collaterals were defined by a hypoperfusion intensity ratio < 0.4.
Results:
One hundred and twenty-nine patients were included, of whom 45 (34.9%) had a brush sign and 63 (48.8%) good collaterals. Brush sign was associated with greater infarct growth (p = 0.01) and larger FIV (p = 0.02). Good collaterals were associated with a smaller baseline ischemic core (p < 0.001), larger penumbra (p = 0.04), and smaller FIV (p < 0.001). Collateral status was not significantly associated with brush sign (p = 0.20) or with infarct growth (p = 0.67). Twenty-eight (22.5%) patients experienced LIG. Univariate regressions indicated that brush sign (odds ratio (OR) = 4.8; 95% confidence interval (CI): [1.9;13.3]; p = 0.004) and hemorrhagic transformation (OR = 1.7; 95%CI: [1.2;2.6]; p = 0.04) were predictive of LIG. In multivariate regression, only the brush sign remained predictive of LIG (OR = 5.2; 95%CI: [1.8-16.6], p = 0.006).
Conclusions:
Brush sign is a predictor of LIG after successful thrombectomy and cerebral collateral status is not.
Key Points:
• Few predictors of ischemic growth are known in ischemic stroke patients achieving successful mechanical thrombectomy. • Our results suggest that the brush sign-a surrogate marker of severe hypoperfusion-is independently associated with large ischemic growth (> 11.6 mL) after successful thrombectomy whereas cerebral collateral status does not.
