Comparison of Satellite Sign and Island Sign in Predicting Hematoma Growth and Poor Outcome in Patients with Primary Intracerebral Hemorrhage.

Objective: Satellite sign (SS) and island sign (IS) are novel noncontrast computed tomography (CT) predictors of hematoma growth. The aim of this study was to compare diagnostic performance of IS and SS in predicting hematoma growth and functional outcome in patients with intracerebral hemorrhage (ICH).

Methods: The study included patients with ICH who underwent baseline CT scan within 6 hours of symptom onset and follow-up CT scan within 36 hours after initial CT between July 2012 and April 2017. Sensitivity, specificity, positive predictive value, and negative predictive value of IS and SS in predicting hematoma growth and functional outcome were assessed. Accuracy of the 2 signs in predicting hematoma growth and functional outcome was analyzed using receiver operating characteristic analysis. Association between the presence of IS and SS and ICH growth was assessed using multivariate logistic regression.

Results: Of 307 patients with ICH, IS was observed in 46 patients (15.0%), and SS was observed in 151 patients (49.2%). Rates of hematoma growth were 40.4% in SS+ patients, 91.3% in IS+ patients, 18.4% in SS-IS- patients, 21.1% in SS+IS- patients, 100% in SS-IS+ patients, and 90.5% in SS+IS+ patients. After adjusting for potential confounders, IS remained an independent predictor for hematoma growth and poor functional outcome. The area under the curve of IS was significantly larger than the area under the curve of SS in predicting hematoma growth (P = 0.001).

Conclusions: IS seems to be an optimal shape irregularity imaging marker for predicting hematoma growth and functional outcome in patients with ICH.