Periportal tracking in pediatric blunt abdominal trauma. Correlation with liver enzymes and liver injury.

This is a retrospective study of the computed tomography (CT) examinations and medical records of 243 consecutive pediatric patients sent for CT studies after blunt abdominal trauma. The purpose of the study was to determine the frequency and significance of periportal tracking identified by CT, and correlate this finding with liver enzyme levels and liver injury. Periportal tracking (PPT) was divided into four grades (0-3) depending upon the distribution of decreased attenuation adjacent to the portal vessels. Circumferential PPT extending to the periphery of the liver (grade 3) was found in 20/243 children. They had a higher incidence of liver parenchymal injury seen on CT 20% versus 0.5% in combined PPT grades 0-2. Sixteen children with grade 3 PPT and no liver injury had significantly elevated liver enzymes as compared to children with combined 0-2 grade PPT. Eleven of the 20 children with grade 3 PPT had no other CT evidence of intraabdominal injury and none of these patients developed intraabdominal hemorrhage. Thus, grade 3 periportal tracking as an isolated abnormality did not indicate a clinically significant liver injury in any patient.