Leakage sign for acute subdural hematoma in clinical treatment

BACKGROUND: Acute subdural hematoma (ASDH) is a serious traumatic disease, and predictive methods for hematoma growth are necessary to decide whether emergent operation is necessary. This study aimed to evaluate the incidence of “leakage” using computed tomography angiography (CTA) in patients with ASDH and to identify its prognostic value. METHODS: Sixty-seven patients with ASDH were examined using CTA (mean age 64.1 ± 20.6 years; 24 men) by analyzing two serial scans (CTA phase and delayed phase). We defined a positive leakage sign as a > 10% increase in Hounsfield units (HU) in the region of interest. Hematoma expansion was determined using plain CT after 24 h in patients who did not undergo emergent surgery. RESULTS: Of the 67 patients, conservative therapy was administered to 35 patients; of these patients, 9 showed hematoma expansion, and 8 of these 9 patients (88.9%) showed positive leakage signs. The sensitivity and specificity of leakage signs to hematoma expansion in the no-surgery group were 88.8% and 76.1%, respectively. All positive leakage signs were found within 4.5 h of injury; patients showing negative leakage signs showed a decreased tendency towards hematoma 24 h after injury. Patients presenting with positive leakage signs had poor outcomes. CONCLUSIONS: The results indicated that the leakage sign is a sensitive predictor of hematoma expansion and poor outcomes in ASDH. If the hematoma is small but leakage sign-positive, strict observation is necessary and aggressive surgery may improve outcomes.