Evolution Patterns of Spot Sign to Stratify Intracerebral Hemorrhage Expansion Risk

Spot sign is the strongest imaging marker of hematoma expansion (HE). We describe spot sign evolution patterns on multiphase computed tomographic angiography in acute intracerebral hemorrhage and assess their association and predictive performance for HE.

Acute patients with intracerebral hemorrhage undergoing noncontrast computed tomography and multiphase computed tomographic angiography were included from Foothills Medical Center, Calgary, Alberta, Canada (development cohort) and Vall d'Hebron Hospital, Barcelona, Spain (validation cohort). Expert readers assessed the spot sign on axial maximum intensity projection across 3 multiphase computed tomographic angiography phases. Patterns were no spot sign (pattern 0), spot sign with no expansion (pattern I), circular expansion (pattern II), and linear/chaotic expansion (pattern III). Logistic regression, adjusted for baseline covariates, assessed associations with HE (≥6 mL or a 33% volume increase). Predictive performance (c-statistic) was compared between spot sign patterns and simple spot sign presence.

In the development cohort (n=217), 67 (30.9%) patients were spot sign positive, and 51 (23.5%) experienced HE: pattern 0, 8.7%; pattern I, 38.8%; pattern II, 50%; and pattern III, 71.1% (adjusted odds ratio, 3.40 [95% CI, 2.35-4.93] per each pattern increase). The predictive performance of spot sign pattern was not superior to simple spot sign presence (c-statistic, 0.810 versus 0.772; P=0.059). In the validation cohort (n=274), 76 (27.7%) patients were spot sign positive, and 67 (24.5%) experienced HE: pattern 0, 14.5%, pattern I, 50%; pattern II, 23.5%; and pattern III, 63.4% (adjusted odds ratio, 1.92 [95% CI, 1.48-2.49] per each pattern increase). The predictive performance of spot sign pattern was not superior to simple spot sign presence (c-statistic, 0.707 versus 0.712; P=0.727).

Spot sign evolution patterns were significantly associated with HE, yet they did not outperform spot sign presence alone in predicting HE.