Fellows' Journal Club: Contrast Extravasation on CT Angiography Predicts Hematoma Expansion and Mortality in Acute Traumatic Subdural Hemorrhage

BACKGROUND AND PURPOSE:The presence of active contrast extravasation at CTA predicts hematoma expansion and in-hospital mortality in patients with nontraumatic intracerebral hemorrhage. This study aims to determine the frequency and predictive value of the contrast extravasation in patients with aSDH.MATERIALS AND METHODS:We retrospectively reviewed 157 consecutive patients who presented to our emergency department over a 9-year period with aSDH and underwent CTA at admission and a follow-up NCCT within 48 hours. Two experienced readers, blinded to clinical data, reviewed the CTAs to assess for the presence of contrast extravasation. Medical records were reviewed for baseline clinical characteristics and in-hospital mortality. aSDH maximum width in the axial plane was measured on both baseline and follow-up NCCTs, with hematoma expansion defined as >20% increase from baseline.RESULTS:Active contrast extravasation was identified in 30 of 199 discrete aSDHs (15.1%), with excellent interobserver agreement (κ = 0.80; 95% CI, 0.7–0.9). The presence of contrast extravasation indicated a significantly increased risk of hematoma expansion (odds ratio, 4.5; 95% CI, 2.0–10.1; P = .0001) and in-hospital mortality (odds ratio, 7.6; 95% CI, 2.6–22.3; P = 0.0004). In a multivariate analysis controlled for standard risk factors, the presence of contrast extravasation was an independent predictor of aSDH expansion (P = .001) and in-hospital mortality (P = .0003).CONCLUSIONS:Contrast extravasation stratifies patients with aSDH into those at high risk and those at low risk of hematoma expansion and in-hospital mortality. This distinction could affect patient treatment, clinical trial selection, and possible surgical intervention.

Acute traumatic subdural hemorrhage carries a mortality rate of 68% in patients who are in a coma at the time of presentation.^1–4 The incidence of aSDH is approximately 21% in patients with severe TBI⁴ and decreases to 11% in patients with mild and moderate TBI.⁵ Mortality secondary to aSDH has been related to initial hematoma size, the presence of additional brain injury, midline shift, comatose state, and delay in hematoma evacuation >2 hours after arrival to the emergency department.^6,7 The decision to undertake surgical intervention versus expectant management of aSDH is based on hematoma size, the presence of midline shift, admission GCS score, and hematoma growth.⁸ Early hematoma evacuation (<4 hours) has been shown to improve intracranial pressure and therefore brain perfusion, with a decrease in mortality compared with delayed surgical intervention in comatose patients with severe TBI.⁴ Although a significant proportion of patients are treated nonoperatively (noncomatose patients and comatose patients with aSDH <10 mm in width and/or <5 mm of midline shift), a subset of these aSDHs will expand, necessitating delayed operative intervention. The strong relationship between mass effect and mortality suggests that hematoma expansion is probably deleterious for brain perfusion and clinical outcome.⁹ However, to date, no reliable predictors of aSDHs expansion in the initial 48 hours have been identified. Identifying such a predictor may be helpful in the clinical decision to triage patients to early surgical intervention versus expectant management.Prior studies have found that the presence of active contrast extravasation at CTA, defined as the spot sign, is a powerful predictor of hematoma expansion and in-hospital mortality in patients with primary intracerebral hemorrhage.^9–15 However, to date, no studies have assessed the frequency and predictive value of this important finding in patients with aSDH.In our emergency department, CTA of the head and neck is frequently performed in patients who present with craniocervical trauma to detect vascular injury.^15,16 Subsets of these patients also have an associated aSDH. This study aims to determine the frequency and predictive value for hematoma expansion and in-hospital mortality of the CTA contrast extravasation in patients with aSDH.