Clinical Applications of the Computed Tomography Angiography Spot Sign in Acute Intracerebral Hemorrhage

Abstract

Spontaneous intracerebral hemorrhage (ICH) is the most fatal form of stroke, with 1-month morality rates often exceeding 40% and rates of death or severe disability exceeding 75%.1,2 Nearly 20 years ago, the first observational studies demonstrated that hematoma volume on presentation was among the most potent predictors of survival and functional outcome.3 Subsequent studies identified the frequent occurrence of hematoma expansion after the initial computed tomography (CT) scan.4 Occurring in ≤40% of patients, this expansion further contributes to poor outcome.5,6 These observations have made the arrest of expansion the most common target for acute clinical trials in ICH.7–9 Thus far, the specific targeting of hematoma expansion in clinical trials has yet to yield improvement in clinical outcome. This may be attributed to difficulty in identifying those individuals most likely to benefit from the intervention, those who will experience hematoma expansion. Risk factors for expansion include early presentation, baseline hematoma volume, and warfarin use.4,10,11 Even among patients presenting within 3 hours, however, expansion severe enough to cause clinical deterioration occurs in no more than 40%.4,6–8 The CT angiography (CTA) spot sign has emerged in recent years as a potent predictor of hematoma expansion, and a potential tool in guiding therapies in both research and clinical care. ### Definition First described in 1999,12 the CTA spot sign has evolved in its definition from the broader concept of contrast extravasation, comprising high-density material or contrast leakage within the hematoma,12–14 to encompass foci of enhancement within the hematoma on CTA source images.15 Although definitions of the spot sign used in individual studies continue to vary, all are variations on this standard (Table 1). In 2009, a spot sign score was …