Impact of Onset-to-imaging Time on the Predictive Value of the Leakage Sign in Supratentorial Hemorrhage

Intracerebral hemorrhage is frequently complicated by hematoma expansion, which is a major determinant of poor outcomes. Leakage sign, defined as progressive contrast extravasation on delayed computed tomography after angiography, has been proposed as a predictor of hematoma expansion. However, the relationship between onset-to-imaging time, hemorrhage location, and leakage sign positivity remains unclear. Data from 144 patients with primary supratentorial intracerebral hemorrhage were retrospectively collected and divided into 2 groups: leakage sign-positive (n = 58) and leakage sign-negative (n = 86) groups. Clinical characteristics, radiological findings, and outcomes were compared, and correlations between hematoma size, onset-to-imaging time, and blood pressure at admission were assessed. Leakage sign-positive patients were significantly older, more frequently underwent antithrombotic therapy, and exhibited larger hematomas, a higher incidence of spot sign(s), a greater need for surgical intervention, and worse outcomes than their leakage sign-negative counterparts. Leakage sign was detectable within 5 hours of onset. In putaminal hemorrhage, hematoma size demonstrated a significant time-dependent increase, particularly in patients who were leakage sign-positive. Moreover, in leakage sign-positive putaminal hemorrhage, admission systolic blood pressure was strongly correlated with hematoma size, suggesting a synergistic effect between hypertension and ongoing bleeding. In contrast, there was no significant correlation between time and hematoma size in thalamic or subcortical hemorrhages, although trends were noted in subcortical cases. These findings indicate that leakage sign positivity reflects ongoing hyperacute bleeding, with diagnostic validity limited to within 5 hours of onset. Early detection of leakage sign, especially in cases of putaminal hemorrhage, may help identify high-risk patients who could benefit from aggressive interventions to mitigate hematoma expansion and improve outcomes.