Dual-Energy CT for Abdominal and Pelvic Trauma

Computed tomography (CT) is key to the assessment of hemodynamically stable patients with blunt or penetrating trauma to the abdomen and pelvis. Dual-energy (DE) CT is a technology that allows acquisition of data at both high and low kilovolt peaks, allowing materials that have different x-ray absorption behaviors as a function of kilovolt peak (such as iodine) to be differentiated and quantified. DE CT has a variety of postprocessing applications that may be helpful in abdominal and pelvic trauma, including iodine-selective imaging, virtual monenergetic imaging, and virtual noncalcium imaging. Both iodine-selective imaging and virtual monoenergetic imaging can increase the conspicuity of traumatic solid-organ and hollow visceral injuries, making injuries easier to detect and categorize. Iodine-selective imaging, through the use of iodine maps and virtual noncontrast images, can assist in the evaluation of active contrast extravasation. Virtual noncalcium images can unmask bone marrow edema, improving detection of subtle fractures. The purpose of this review article is to familiarize radiologists with the basic physics and technical principles of DE CT, common postprocessing techniques, and the potential added value of DE CT in patients with abdominal and pelvic trauma. The technical limitations of DE CT are also reviewed, as are diagnostic pitfalls and common challenges in interpretation. (C) RSNA, 2018