Angiography, Contrast extravasation, Pelvic fracture, Transcatheter embolization

20 years old/male

The patient was admitted to the emergency department because of accidental fall from a height of 10m. On admission, he was alert, with a systolic blood pressure of 120mmHg, and laboratory finding of acute blood loss with Hb 7.1g/dL with abdominal distension.

Extraperitoneal suprapubic hematoma from the aberrant obturator artery

Emergency abdominal CT was performed to evaluate bleeding focus. Cystogram and abdominal CT revealed an extraperitoneal hematoma of the suprapubic area and marked widening of symphysis pubis(Fig 1). The CT findings were highly suggestive of inferior epigastric and obturator arterial injury. Enhanced study showed an extravasation within the mass indicative of arterial bleeding.

A. Cystogram shows an external compression of the bladder, suggestive of perivesical hematoma, associated with diastatic fracture of the symphysis pubis. B. Pelvic CT shows a hematoma with extravasation of contrast in pubic area (arrow), indicating active hemorrhage.

To identify the location of the bleeding site, digital subtraction angiography was performed. Selective angiogram of right common iliac artery showed two contrast extravasations or bleeding points at suprapubic area(Fig. 2A). Selective internal iliac arteriogram showed only one bleeding point from the obturator artery(Fig. 2B). After superselective cannulating into the feeding branch from the obturator artery by using a coaxial microcatheter, embolization was performed with gelfoam particles(Fig. 2C). Follow-up right common iliac angiogram showed persistent contrast extravasation and identified feeding branch of aberrant obturator artery from the inferior epigastric artery(Fig. 2D). Additional selective embolization was performed with gelfoam particles.

A. Pelvic angiogram shows two contrast extravasations in pubic area (thin arrows). The inferior epigastric artery (thick arrow) and aberrant obturator artery (arrowheads) are noted. B. Internal iliac arteriogram shows active bleeding from the obturator artery (arrow). C. Selective embolization of obturator artery from the internal iliac artery was done. D. Persistent contrast extravasation being fed by aberrant obturator artery (arrows), a branch of inferior epigastric artery, is identified on common iliac angiogram. So additional selective bleeding artery embolization was done.

The most patients with an unstable pelvic fracture have pelvic arterial hemorrhage and high mortality. Therefore, because angiography is not only diagnostic but also therapeutic, it plays a very important role in the management of severely injured patients(1, 2). There are many anatomic variations in the pelvic arteries and the knowledge of accurate vascular anatomy is crucial to avoid inadequate embolization of bleeding arteries(3, 4). The "corona mortis" is presence of an abnormal anastomosis vessel between the external iliac or inferior epigastric arteries or veins and the obturator system. The aberrant obturator artery which is a part of the corona mortis usually originates from the inferior epigastric artery(5-8). The reported incidence of an aberrant obturator artery or anomalous origins of obturator artery range from 10% to 40% (6). The laceration of corona mortis can results in uncontrolled, profuse, in spite of transarterial embolization of internal iliac branches, and persistent pelvic bleeding(7). So if the successful hemostasis was not achieved by means of selective embolization of the internal iliac artery, the interventionist should be aware of the variant pelvic vessels, such as the aberrant obturator artery or corona mortis from the external iliac artery.

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