Post-traumatic liver and splenic pseudoaneurysms in children: Diagnosis, management, and follow-up screening using contrast enhanced ultrasound (CEUS).

BACKGROUND: Pseudoaneurysm (PA) formation following blunt and penetrating abdominal trauma is a recognized complication in solid organ injury, usually diagnosed by contrast-enhanced CT (CECT) imaging. Delayed rupture is a potentially life-threatening event, although its frequency is not known in pediatric trauma. Contrast enhanced ultrasound (CEUS) is a novel radiation-free alternative to CECT with the potential to identify PA.

METHODS: A retrospective review of consecutive cases of significant liver and splenic injuries admitted to single institution (tertiary and quaternary referrals) over more than a 12year period was performed. From 2011, CEUS was performed routinely postinjury (5-10days) using SonoVue™ as contrast. Initially, CECT and CEUS were performed in tandem to ensure accurate correlation.

RESULTS: From January 2002-December 2014, 101 (73M) children [median age was 14.2 (1.3-18)years] with liver and splenic injuries were admitted. Injuries included: liver [n=57, grade 3 (1-5)], splenic [n=35, grade 3 (1-5)], and combined liver/spleen [n=8, (1-4)]. Median Injury Severity Score (ISS) was 13 (2-72). The predominant mechanisms of injury were blunt trauma n=73 (72%) and penetrating trauma n=28 (28%). Seventeen children (17%) developed PA. Six children became symptomatic (35%), and five went on to have embolization [at 7 (3-11)days]. These were detected by CECT (n=4) and CEUS (n=2). Eleven children remained asymptomatic [detected by CECT (n=8) and CEUS (n=3) at median 5 (4-8)days]. One underwent embolization owing to evidence of interval bleeding. Sensitivity of CEUS at detection of PA was 83%, with specificity of 92% (PPV=71%, NPV=96%). There was no association between grade of injury and presence of PA in either liver or splenic trauma (P=0.4), nor was there an association between size of PA and symptoms (P=0.68). Children sustaining splenic PA were significantly younger than those with hepatic PA (P=0.03). Follow-up imaging confirmed resolution of PA in 16 cases. One child was lost to follow-up.

CONCLUSIONS: The incidence of PA is higher than previously reported in the pediatric literature (<5%). Postinjury imaging appears mandatory, and CEUS appears to be highly sensitive and specific for diagnosis and follow-up.