Predicting Intracerebral Hemorrhage Expansion With Noncontrast Computed Tomography: The BAT Score

BACKGROUND AND PURPOSE—Although the computed tomographic angiography spot sign performs well as a biomarker for hematoma expansion (HE), computed tomographic angiography is not routinely performed in the emergency setting. We developed and validated a score to predict HE-based on noncontrast computed tomography (NCCT) findings in spontaneous acute intracerebral hemorrhage. METHODS—After developing the score in a single-center cohort of patients with intracerebral hemorrhage (n=344), we validated it in a large clinical trial population (n=954) and in a multicenter intracerebral hemorrhage cohort (n=241). The following NCCT markers of HE were analyzedhypodensities, blend sign, hematoma shape and density, and fluid level. HE was defined as hematoma growth >6 mL or >33%. The score was created using the estimates from multivariable logistic regression after final predictors were selected from bootstrap samples. RESULTS—Presence of blend sign (odds ratio, 3.09; 95% confidence interval [CI],1.49–6.40; P=0.002), any intrahematoma hypodensity (odds ratio, 4.54; 95% CI, 2.44–8.43; P