Minimal Hypodensity Sign Predicts Early Hematoma Expansion and Poor Outcome in Patients with Intracerebral Hemorrhage

Abstract

Background: Early hematoma expansion in intracerebral hemorrhage (ICH) patients is associated with poor outcome. We aimed to investigate whether a noncontrast computed tomography (NCCT) sign named minimal hypodensity sign (MHS) predicted hematoma expansion and poor outcome. Methods: This study involved spontaneous ICH patients of two cohorts who underwent baseline NCCT scan within 6 h after ICH onset and follow-up NCCT scan within 24 h after initial CT scan. We first defined MHS by retrospectively analyzing the data from derivation cohort. Then a prospective study on the validation cohort of three clinical centers was performed for determining the association between MHS and hematoma expansion as well as poor outcome (modified Rankin Scale scores>3) at 90 days by using univariate and multivariate logistic regression analyses. Results: 148 ICH patients were included in the derivation cohort. MHS was defined as a hypoattenuating area with or without a distinct margin within the hematoma, the minimal CT value of which was ≤31 Hounsfield units. A total of 311 ICH patients were enrolled in the validation cohort and 73 patients (23.5%) was observed MHS. The multivariate logistic regression analysis demonstrated MHS was an independent predictor for hematoma expansion (P<0.001) and poor outcome (P<0.001). The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of MHS for hematoma expansion and poor outcome prediction were 64.0%, 92.0%, 75.3%, 87.0%, 84.2% and 45.1%, 92.7%, 82.2%, 69.3%, 72.3%, respectively. Conclusions: MHS is a reliable predictor for early hematoma expansion and poor outcome in patients with ICH. Funding Statement: This research was supported by grants from the National Natural Science Foundation of China (No. 81500998) and Science and Technology Commission of Shanghai Municipality (No. 16140903200). Declaration of Interests: The authors declare that they have no competing interests. Ethics Approval Statement: This study was approved by and studied in accordance with the ethical standards of Fudan University Ethics Committee.