The Role of Magnetic Resonance in Evaluating Abdominopelvic Trauma - Part 2: Trauma in Pregnancy, Vascular, and Genitourinary Injuries.

Trauma is an important cause of mortality, particularly in the young. While computed tomography (CT) is the mainstay of body imaging in the setting of trauma, magnetic resonance (MR) imaging can be useful in stable patients. Although more commonly used in spinal and musculoskeletal trauma, MR also has a role in abdominopelvic trauma. Broadly, its uses include clarification of equivocal cases, monitoring complications of trauma, particularly with solid organ injury, or as a primary imaging modality for patients with low suspicion for injury for whom avoiding ionizing radiation is a priority-namely, in pediatric and pregnant patients. In this two-part review article, we will review clinical scenarios where this may be encountered, utilizing case examples. Our second installment will focus on the use of MR in pregnant patients and in the characterization of vascular and genitourinary trauma. Body MR can be useful in pregnant patients in characterizing injuries both specific for and not specific for pregnancy. Placental injuries and hematomas in particular may be better seen on MR relative to CT, owing to its superior contrast resolution. MR angiography can be performed either without or with contrast and can be useful to monitor low-grade traumatic aortic injuries. Renal and ureteral injuries can be followed with MR to help identify urine leaks, either in a delayed presentation or in patients who have an iodinated contrast allergy. Lastly, penile injuries are often imaged with ultrasound, but may benefit from additional imaging with MR when the tunica albuginea cannot be completely seen due to overlying hematoma.