Diagnostic imaging in blunt trauma of the abdomen.

Diagnostic imaging is a useful adjunct in evaluating the stable patient with blunt trauma to the abdomen who is not in need of emergent celiotomy. Plain and contrast roentgenography, sonography, scintigraphy, CT and angiography have unique applications in identifying injuries caused by blunt forces. Roentgenograms of the cervical spine, upright chest and pelvis with intravenous pyelography are indicated early to identify injuries that may jeopardize the patient's outcome. Upper gastrointestinal series, with water-soluble contrast medium, are useful in confirming suspected diaphragmatic and duodenal abnormalities. Urethral, bladder and ureteric injuries are readily diagnosed with the results of retrograde urethrography, cystography and pyelography, respectively. Ultrasound is particularly useful in diagnosing and following post-traumatic complications by identifying and localizing hematomas and other fluid collections. Radionuclide scintigraphy is a reliable screening method for injuries to the spleen, liver and kidneys but most importantly, scans are useful in observing patients treated without an operation. Because of the unsurpassed sensitivity and specificity of the recently introduced CT scanners, CT is the roentgenologic screening method of choice in the stable multi-trauma patient with blunt abdominal injury. However, angiography is still the most informative method of assessing vascular injury and, at times, may be both diagnostic and therapeutic. Although, it should be reserved for selected instances when noninvasive studies are inconclusive or performed incidental to necessary pelvic or thoracic aortography. The type and extent of suspected injury usually dictates the nature of the roentgenologic evaluation. Studies that duplicate previous findings or interfere with the ability to pursue needed additional investigative studies should be avoided. Finally, it is crucial that celiotomy should not be delayed by time-consuming studies in the unstable patient.