Pediatric Abdominal Trauma Imaging

Carlos J. Sivit, MD


Appl Radiol. 2013;42(5):8-13. 

In This Article

Hollow Viscus Injury

Bowel injury is uncommon after blunt trauma in children. However, partial thickness injury resulting in intramural hematoma, or full-thickness injury resulting in bowel rupture, can occur. Most bowel injuries in children occur following motor vehicle crashes and are due to compression of bowel and mesentery by the seat belt.[26] These children typically display linear lap belt ecchymosis across the lower abdomen and/or flank.[26]

Intramural hematoma results from hemorrhage into the bowel wall following a partial-thickness tear. The most common location is the duodenum. The injury can usually be managed nonoperatively. Large hematomas can result in a proximal small-bowel obstruction. The CT appearance is that of focal bowel-wall thickening that is often eccentric. No extraluminal air or extravasated contrast material should be present.

Bowel rupture in children most commonly occurs in the mid-to-distal small intestine, usually the jejunum. Signs of bowel rupture may be subtle on a CT scan. Extraluminal air is noted on CT in only approximately one-third to one-half of cases.[27–29] Review of the examination at a wide window setting (> 500) helps to detect small amounts of extraluminal air (Figure 8). Oral contrast extravasation is rarely seen.[30] The most frequent CT findings associated with bowel rupture are "unexplained" peritoneal fluid (moderate to large amounts of fluid in the absence of solid viscus injury or bony pelvic fracture (Figure 9).[27] Approximately 50% of children with moderate to large amounts of peritoneal fluid as the only finding on CT following blunt trauma have a bowel injury.[2] Additional CT findings associated with bowel rupture include abnormally intense bowel-wall enhancement, focal bowel-wall discontinuity, bowel dilatation, bowel-wall thickening, and streaky infiltration of mesenteric fat.[27–29]

Figure 8.

Bowel rupture with extraluminal air. Contrast-enhanced CT scan through the upper abdomen demonstrates several small air collections anterior to the liver.

Bladder injury is also uncommon in children. Bladder rupture can be intraperitoneal or extraperitoneal; combined injuries may occur. Extraperitoneal bladder rupture occurs more frequently than intraperitoneal rupture. Intraperitoneal rupture typically results from shearing of the distended bladder by a lap belt, whereas extraperitoneal rupture often results from laceration by a bony spicule from a pelvic fracture.[30]

Bladder distention is essential in detecting bladder injury at CT in order to demonstrate extravasation of IV contrast material (Figure 10). CT cystography is the method of choice for the evaluation of suspected bladder rupture.[31–33] CT cystography is performed by administering dilute iodinated contrast into the bladder in a retrograde fashion until the flow stops followed by clamping of the Foley catheter.[31–32] Sagittal and coronal reformations help to localize the site of bladder rupture.[32]