Sonographic detection of blunt hepatic trauma: Hemoperitoneum and parenchymal patterns of injury

Objectives: To determine the sensitivity and utility of emergency sonograph y for the detection of blunt hepatic injury (BHI) in patients with abdomina l trauma and to describe parenchymal sonographic patterns of BHI. Methods: This report was a prospective clinical study in which the findings of all patients who had emergency sonograms were recorded on a data sheet by the initial sonographer and interpreting physicians. All patients with h epatic injuries during this period were identified and physical examination , laboratory, computed tomographic and intraoperative findings were compare d with the prospective data sheets, Results: From January of 1995 to December of 1998, 2,622 emergency sonogram s were performed, and in this group, a total of 146 patients had BHI. Emerg ency sonograms allowed detection of free fluid in 98 patients (67%), and pa renchymal injury with no free fluid in seven patients (5%), There were 41 f alse negatives (28%), The most common pattern identified on a sonogram was a discrete area of increased echogenicity followed by a diffuse hyperechoic pattern, Seventy-six patients (52%) had concomitant intra-abdominal injuri es, including spleen (n = 46), bowel (n = 30), and kidney (n = 19), There w ere 102 exploratory laparotomies performed. Abdominal tenderness or distent ion was present in 127 patients (87%), and 108 patients had right rib fract ures (74%). Based on detection of free fluid, parenchymal injury, or both, the overall sensitivity of sonography for the detection of BHI was 72% but was 98% for grade III or higher injuries, Conclusion: Emergency sonography is sensitive for the detection of grade In or higher liver injuries resulting from blunt abdominal trauma. Sonography may also reveal BHI on the basis of parenchymal abnormality, with a discre te hyperechoic area the most commonly encountered pattern.