An IV contrast CT scan is the preferred method when evaluating a patient with possible hollow viscus injury. In the past, oral and IV contrast was frequently given, but the use of oral contrast has been found to be unnecessary in the majority of cases and adds the potential for aspiration. Intestinal injuries may be either intraperitoneal, retroperitoneal, or both. Radiographic findings may include free air in the abdomen or extravasation of intestinal contents if there is a perforation of the viscus. If there is a transmural injury or a vascular injury with disruption of arterial or venous blood flow to the intestine, bowel wall thickening may be seen. Vascular injuries may also present as mesenteric infiltration or stranding. Hemoperitoneum is a common finding in abdominal trauma from either solid organ or intestinal origin. Therefore, if no solid organ injury is identified, a bowel or mesenteric source of the bleeding should be considered. Unlike intraperitoneal bleeding, the sources of retroperitoneal hematomas are easier to identify since the hematoma typically resides near the area of injury. For example, a retroperitoneal hematoma identified near the duodenum is usually indicative of a duodenal injury.