Prognostic value of CT contrast staining after endovascular therapy in basilar artery occlusion stroke

Background Contrast staining signifies prolonged tissue absorption of iodinated contrast media following endovascular therapy (EVT) for large-vessel occlusion stroke, indicating blood–brain barrier disruption. With EVT becoming the standard treatment for treating basilar artery occlusion (BAO) stroke and considering the substantial variability in patient outcomes, our study aimed to determine the prognostic significance of post-interventional contrast staining in BAO stroke cases. Methods We included BAO patients who received postinterventional non-contrast CT within 24 h after EVT. Expert radiologists confirmed the presence of contrast staining on CT, and its volume was quantified. Functional outcomes were assessed on the modified Rankin scale (mRS) at 90 days, and an unfavorable outcome was defined as an mRS score of ≥4. A multivariable LASSO-penalized logistic regression analysis was performed to determine the association between contrast staining and other clinical and imaging parameters with functional outcomes. Results A total of 42 patients met the inclusion criteria (15 women, 35.7%). Contrast staining on postinterventional CT was present in 18 patients (42.9%) with a median [interquartile range / IQR] volume of 7.9 mL [3.7–14.6]. Patients with contrast staining had worse outcomes, with higher mRS scores at 90 days (median [IQR]: 6 [4–6] vs. 2 [1–4], p < 0.001). A multivariable LASSO analysis revealed a significant association of contrast staining with clinical outcome. Conclusion Contrast staining on postinterventional CT after EVT for BAO is a strong predictor of unfavorable functional outcomes, outperforming other pre- and post-interventional imaging parameters.