Iodine-based dual-energy CT of traumatic hemorrhagic contusions: Relationship to in-hospital mortality and short-term outcome

Background: Traumatic hemorrhagic contusions are associated with iodine leak; however, quantification of leakage and its importance to outcome is unclear. Purpose: To identify iodine-based dual-energy CT variables that correlate with in-hospital mortality and short-term outcomes for contusions at hospital discharge. Materials and Methods: In this retrospective study, consecutive patients with contusions from May 2016 through January 2017 were analyzed. Two radiologists evaluated CT variables from unenhanced admission head CT and follow-up head dual-energy CT scans obtained after contrast material-enhanced whole-body CT. The outcomes evaluated were in-hospital mortality, Rancho Los Amigos scale (RLAS) score, and disability rating scale (DRS) score. Logistic regression and linear regression were used to develop prediction models for categorical and continuous outcomes, respectively. Results: The study included 65 patients (median age, 48 years; interquartile range, 25-65.5 years); 50 were men. Dual-energy CT variables that correlated with mortality, RLAS score, and DRS score were iodine concentration, pseudohematoma volume, iodine quantity in pseudohematoma, and iodine quantity in contusion. The single-energy CT variable that correlated with mortality, RLAS score, and DRS score was hematoma volume at follow-up CT. Multiple logistic regression analysis after inclusion of clinical variables identified two predictors that enabled determination of mortality: Postresuscitation Glasgow coma scale (P-GCS) (adjusted odds ratio, 0.42; 95% confidence interval [CI]: 0.2, 0.86; P = 0.01) and iodine quantity in pseudohematoma (adjusted odds ratio, 1.4 per milligram; 95% CI: 1.02 per milligram, 1.9 per milligram; P = 0.03), with a mean area under the receiver operating characteristic curve of 0.96 6 0.05 (standard error). For RLAS, the predictors were P-GCS (mean coefficient, 0.32 6 0.06; P , .001) and iodine quantity in contusion (mean coefficient, 20.04 per milligram 6 0.02; P = 0.01). Predictors for DRS were P-GCS (mean coefficient, 21.15 6 0.27; P , .001), age (mean coefficient, 0.13 per year 6 0.04; P = .002), and iodine quantity in contusion (mean coefficient, 0.19 per milligram 6 0.07; P = .02). Conclusion: Iodine-based dual-energy CT variables correlate with in-hospital mortality and short-term outcomes for contusions at hospital discharge.