Imaging of Pediatric Blunt Abdominal Trauma

The diagnostic imaging test of choice for blunt trauma to the abdomen and pelvis is contrast enhanced CT. Conventional sonography should be reserved for subjects too hemodynamically unstable to tolerate CT. CT represents a significant radiation burden to young patients. All practitioners should adhere to ALARA (as low as reasonably achievable) principles in minimizing radiation dose to patients. However, when appropriately indicated, CT should be performed because short-term benefits in the acute trauma setting far outweigh long-term risk of radiation. Despite intra- and inter-observer variability in grading abdominal solid visceral injuries, higher grade injuries generally predict higher chances of failed nonoperative management. In the case of pancreatic injury, radiologists should pay special attention for signs of pancreatic ductal injury. Isolated free fluid without obvious source in a trauma patient should be considered suspicious for hollow viscus injury if the fluid is in an interloop location, larger in quantity, or less than 20 Hounsfield units in attenuation. These should prompt careful re-evaluation of CT or serial physical/ultrasound examination. Radiologists may be the first to suggest nonaccidental trauma as a cause of abdominal visceral injury in children, by noticing that the mechanism does not explain the injuries seen or by recognizing high-specificity fractures on imaging obtained for evaluation of abdominal injuries.