A CASE OF A MIDDLE COLIC PSEUDOANEURYSM PRESUMED TO HAVE RUPTURED 5 YEARS AFTER AN ABDOMINAL BLUNT TRAUMA

Abstract

A 63-year-old man was seen at our hospital because of abdominal pain. In addition to anemia, temporal low blood pressure was observed. Although no anal bleeding was seen, abdominal CT scan showed intraabdominal fluid collection, and it was confirmed to be blood by aspiration. Abdominal CT scan showed an aneurysm-like structure in the right upper abdominal cavity, but angiogram could not show any aneurysm nor bleeding point. Because the patient had no past medical history other than a blunt abdominal injury 5 years earlier, and his general condition was stable, we follwed up his clinical course. Two weeks later, angiography showed an aneurysm in the peripheral area of middle colic artery. As the catheter embolization had a risk of generating necrosis of the colon, a 3-cm sized hematoma containing the aneurysm and the right colon were resected under laparotomy. Microscopically, peripheral small artery in the hematoma had partial deficit of tunica media and internal elastic layer, replaced by fibro-cellular tissue. As no other vascular lesion was identified, the blunt trauma 5 years earlier was considered to be the cause of psudoaneurysm. There have been only four Japanese cases of traumatic pseudoaneurysm of the branches of superior mesenteric artery (including our case), but such a long interval between abdominal blunt trauma and rupture of pseudoaneurysm has not been reported except our case.