Abstract WP341: Imaging Predictors of Intracerebral Hematoma Expansion in Hyperacutely-Presenting Patients

Abstract

Background: Several noncontrast CT findings may increase risk of intracerebral hemorrhage (ICH) expansion, including ICH volume, location, margin irregularity, heterogeneity, the blend sign, and leukoaraioisis. Hyperacute EMS-transported patients have more frequent hematoma progression and may have distinctive predisposing imaging features. Methods: We analyzed consecutive patients enrolled in the NIH Phase 3 Field Administration of Stroke Therapy - Magnesium (FAST-MAG) prehospital trial and who had both ED-arrival and 6 to 48h follow-up brain CT or GRE-MRI. Hematoma expansion (HE) was defined as hematoma volume growth by ≥ 6ml. Results: Among 262 ICH patients meeting entry criteria, age was 64.8 (±12.9), 32.4% were female, arrival GCS was median 15 (IQR 11-15), and arrival NIHSS median 15 (IQR 9-24). Initial imaging was with CT in 95.8% and GRE-MRI in 4.2%. Median time from last known well to first imaging was 80 min (IQR 66-98) and from first to follow-up imaging 16.7 hr (IQR 11.3-22.3). Overall, 30.5% of patients experienced hematoma expansion. Univariate imaging predictors of HE were: hematoma volume, 25.1 vs 18.6 ml, p<0.001; perihematomal edema volume, 16.0 vs 11.7 ml, p<0.001; basal ganglia location, 63.7% vs 46.2%, p=0.009; moderate-severe midline shift, 31.3% vs 12.6%, p<0.001; greater hematoma shape irregularity, 2.8 vs 2.3, p=0.01; and high hematoma density heterogeneity, 62.5% vs 40.4%, p=0.001. Intraventricular hemorrhage, leukoaraiosis, and blend sign were not associated with HE. In multivariable analysis, independent imaging predictors of HE were: moderate-severe midline shift (aOR 3.7, 95%CI 1.4-9.5) and hematoma density heterogeneity (aOR 2.2, 95%CI 1.1-4.4). HE was associated with substantially reduced 90d functional independence (mRS 0-2, 15.0% vs 36.5%, p=0.001) and increased 90d mortality (46.3% vs 11.0%, p<0.001). Conclusions: Among hyperacute, EMS-transported intracerebral hemorrhage patients, several conventional and novel imaging findings on noncontrast CT are associated with hematoma expansion. Key independent predictors of hematoma growth are early evidence of moderate-severe midline shift and hematoma density heterogeneity.