SIGNIFICANCE OF PERIPORTAL LOW-ATTENUATION ZONES FOLLOWING BLUNT TRAUMA IN CHILDREN

The CT scans of 400 consecutive children evaluated with CT following b lunt abdominal trauma were evaluated to determine the frequency of per iportal low-attenuation zones, assess patterns of associated intraabdo minal injury, and examine clinical outcome. Periportal low-attenuation zones were noted in 60 children (I 5 %). The presence of these zones was associated with a significantly higher incidence of intraabdominal injury (60 % versus 11 %, p = 0.0001). Injuries most frequently assoc iated with zones of periportal low-attenuation included hepatic (n = 2 3, 38 %), and adrenal ( = 14, 23 %). Children who had periportal low-a ttenuation zones tended to be more physiologically unstable as evidenc ed by a lower Trauma Score (diffuse, 11.9; focal, 13.4) than children without the zones (15. 1, p = 0.0001). The presence of these zones was also associated with a significantly higher mortality rate (I 3 % ver sus 1 %, p = 0.000 1). Ten children who had periportal low-attenuation zones and no hepatic injury on CT had a normal appearing liver on gro ss inspection at surgery or autopsy. In conclusion, periportal low-att enuation zones are common in children who have hepatic injury. These z ones may be seen in conjunction with non-hepatic visceral injury or in the absence of intraabdominal injury. The presence of zones of peripo rtal low-attenuation is associated with a higher index of physiologic instability, and higher mortality.