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 x 5-mm axial, (b) 1.25 x 1.0-mm axial, and (c) 1.25 x 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.