Traumatic injuries: role of imaging in the management of the polytrauma victim (conservative expectation).

Abdominal US and CT play an important role in the initial management of blunt trauma in adults. Ultrasound is an excellent method for detection of free intra-abdominal fluid. It is the modality of choice for initial screening and enables selection of hemodynamically unstable trauma victims with severe hemoperitoneum for immediate surgery. However, even in experienced hands, US is not sufficient to rule out organ injuries reliably. Computed tomography, and particularly multislice CT (MSCT), has several major advantages over US and is currently unsurpassed for the detection of blunt visceral injuries in the abdomen. Computed tomography has a high sensitivity for the detection of parenchymal splenic and hepatic injuries. Injuries of the gastrointestinal tract may be detected with good sensitivity provided that adequate examination technique and careful diagnostic interpretation are combined. The value of CT-based injury-grading systems for predicting the outcome of conservative treatment remains unproven; however, demonstration of direct vascular injuries with CT, e.g., the intrasplenic "contrast blush" sign, may indicate a high likelihood that conservative treatment will fail, thus warranting angiographic embolization or surgery. Monitoring of conservatively treated trauma victims by means of repeat CT studies enables early detection of a variety of delayed, clinically silent complications of trauma, e.g., posttraumatic biloma or bowel devascularization. Catheter angiography may be reserved to selected cases with vascular injuries proven on CT.