The Corona Mortis, a Frequent Vascular Variant Susceptible to Blunt Pelvic Trauma: Identification at Routine Multidetector CT

Purpose: To determine if contrast-enhanced multidetector computed tomography (CT) can demonstrate the "corona mortis" (translated as "crown of death"), a common variant obturator artery originating from the external iliac artery system that is susceptible to pelvic trauma. Methods and Materials: A representative case study is described. The authors evaluated 50 consecutive patients undergoing routine clinically indicated, standard protocol, venous phase contrast-enhanced multidetector CT of the pelvis, 25 with a 16-slice scanner and 25 with a 64-slice scanner. Three data sets were created for each study, as follows: (a) 5 × 5-mm axial, (b) 1.25 × 1.0-mm axial, and (c) 1.25 × 1.0-mm coronal. Three radiologists independently reviewed the images for the presence or absence of corona morti. Results: One hundred hemipelves in 50 patients were evaluated. In total, 29 corona morti were identified, including 10 on the 5-mm axial images, 25 on the 1.25-mm coronal images, and 29 on the 1.25-mm axial images. By consensus agreement, interpretation of challenging cases was easiest with the 64-slice images. Conclusions: The corona mortis variant can be identified on routine contrast-enhanced multidetector CT scans in about one-third of patients. Thin (1.25-mm) CT reconstructions demonstrate this variation much more frequently than 5-mm-thick images. This suggests that the corona mortis may be prospectively identified at contrast-enhanced multidetector CT in pelvic trauma patients and help guide subsequent endovascular embolization. However, further study in the trauma population is necessary to confirm this.