Assessment of blunt splenic trauma: Which imaging scoring system is superior?

Background: Spleen is the most common viscera that may be hurt in blunt abdominal trauma. Operative or nonoperative management of splenic injury is a dilemma. The American Association for the Surgery of Trauma (AAST) is the most common grading system which has been used for the management of blunt splenic injuries. The new recommended grading system assesses other aspects of splenic injury such as contrast extravasation, pseudoaneurysm, arteriovenous fistula, and severity of hemoperitoneum, as well. The aim of this study is to compare and prioritize the cutoff of AAST grading system with the new recommended one.

Materials and Methods: This is a cross-sectional study on patients with splenic injury caused by abdominal blunt trauma referred to Isfahan University of Medical Sciences affiliated Hospitals, Iran, in 2013-2016. All patients underwent abdominopelvic computed tomography scanning with intravenous (IV) contrast. All images were reported by a single expert radiologist, and splenic injury grading was reported based on AAST and the new recommended system. Then, all patients were followed to see if they needed surgical or nonsurgical management.

Results: Based on the findings of this study conducted on 68 patients, cutoff point of Grade 2, in AAST system, had 90.3% (95% confidence interval [CI]: 0.73-0.97) specificity, 51.4% (95% CI: 0.34-0.67) sensitivity, 86.4% (95% CI: 0.64-0.95) positive predictive value (PPV), and 60.9% (95% CI: 0.45-0.74) negative predictive value (NPV) for prediction of surgical management requirement, while it was 90.3% (95% CI: 0.73-0.97) specificity, 45.9% (95% CI: 0.29-0.63) sensitivity, 85% (95% CI: 0.61-0.96) PPV, and 58.3% (95% CI: 0.43-0.72) NPV for the new system ( P = 0.816).

Conclusion: In contrast to the previous studies, the new splenic injury grading method was not superior to AAST. Further studies with larger populations are recommended.