A Case of Segmental Arterial Mediolysis Causing Rupture of the Middle Colic Artery Treated by Laparoscopic Surgery

Abstract

A 43-year-old woman presented with the abrupt onset of severe abdominal pain and diarrhea. When she arrived at our hospital by ambulance, she was in a state of shock and the Hb level was 10.7 g/dl, showing anemia. An abdominal enhanced CT scan revealed a moniliform deformity at the left branch of the middle colic artery, and giant hematoma formation and ascites from the transverse mesocolon to the omental bursa. We suspected that intraabdominal hemorrhage associated with rupture of the left branch of the middle colic artery might occur and employed emergency operation. After laparoscopic surgical removal of the hematoma, the ruptured vessel branching from the left branch of the middle colic artery was treated by clipping hemostasis. The postoperative course was uneventful, and the patient was discharged from our hospital on 15^th postoperative day. An abdominal angiography after the surgery revealed moniliform deformities and multiple aneurysms not only in the left branch of the middle colic artery but also in the splenic, left colic, and sigmoid arteries. According to the clinical diagnostic criteria advocated by Uchiyama and his coworkers, we diagnosed the case as segmental arterial mediolysis (SAM). SAM is a comparatively rare entity causing intraabdominal hemorrhage due to rupture of the abdominal artery. So far only few cases of SAM performed laparoscopic surgery have been reported. From our experience with laparoscopic surgery for SAM which resulted in favorable postoperative course, we consider that laparoscopic surgery might be beneficial for SAM.