 Trauma is the leading cause of mortality for people in the United States who are <45 years of age, and it is the fourth leading cause of death overall [3]. Polytrauma can be defined as an injury to at least two body parts, including the head, neck, chest, abdomen, pelvis, and at least one extremity, with any one or a combination of these injuries being potentially fatal. MR urography (MRU) is also tailored to improve imaging of the urinary tract system. Unenhanced MRU relies upon heavily T2-weighted imaging of the intrinsic signal from urine for evaluation of the urinary tract. IV contrast is administered to provide additional information regarding obstruction, urothelial thickening, focal lesions, and stones. A contrast-enhanced T1-weighted series should include corticomedullary, nephrographic, and excretory Reprint requests to: publications@acr.org Major Blunt Trauma phase. Similar to CTU, hydration or low-dose furosemide can improve urinary tract distension and study quality. Thin slice acquisition and multiplanar imaging should be obtained. MRU is most commonly performed at 1.5T, but imaging at 3T has become more widely used; however, comparison of 3T MRU and CTU has not been published in the literature. Discussion of Procedures by Variant Variant 1: Major blunt trauma. Hemodynamically unstable. Initial imaging. CT Whole Body There is limited literature to support the use of WBCT in patients who are hemodynamically unstable [6,7]. Patients who remain hemodynamically unstable despite initial attempts at resuscitation and who have positive signs for abdominal trauma (eg, a positive FAST) should proceed directly to exploratory laparotomy, with CT imaging deferred until after operative intervention. Patients who have an abnormal chest radiograph in the setting of trauma have clinically significant rates of major injury on CT chest [8].
Major Blunt Trauma.  Trauma is the leading cause of mortality for people in the United States who are <45 years of age, and it is the fourth leading cause of death overall [3]. Polytrauma can be defined as an injury to at least two body parts, including the head, neck, chest, abdomen, pelvis, and at least one extremity, with any one or a combination of these injuries being potentially fatal. MR urography (MRU) is also tailored to improve imaging of the urinary tract system. Unenhanced MRU relies upon heavily T2-weighted imaging of the intrinsic signal from urine for evaluation of the urinary tract. IV contrast is administered to provide additional information regarding obstruction, urothelial thickening, focal lesions, and stones. A contrast-enhanced T1-weighted series should include corticomedullary, nephrographic, and excretory Reprint requests to: publications@acr.org Major Blunt Trauma phase. Similar to CTU, hydration or low-dose furosemide can improve urinary tract distension and study quality. Thin slice acquisition and multiplanar imaging should be obtained. MRU is most commonly performed at 1.5T, but imaging at 3T has become more widely used; however, comparison of 3T MRU and CTU has not been published in the literature. Discussion of Procedures by Variant Variant 1: Major blunt trauma. Hemodynamically unstable. Initial imaging. CT Whole Body There is limited literature to support the use of WBCT in patients who are hemodynamically unstable [6,7]. Patients who remain hemodynamically unstable despite initial attempts at resuscitation and who have positive signs for abdominal trauma (eg, a positive FAST) should proceed directly to exploratory laparotomy, with CT imaging deferred until after operative intervention. Patients who have an abnormal chest radiograph in the setting of trauma have clinically significant rates of major injury on CT chest [8].