Higher levels of ET-1 at T1 significantly correlated with smaller hematoma volumes at T2 (Spearman’s rho = −0.717, p = 0.030) with only a trend toward the statistical significance for ET-1 levels at T0 (Spearman’s rho = −0.617, p = 0.077) (Figure 3). The gene discussed is EDN1; the disease is hematoma.