A Case of Omental Bleeding as a Result of Segmental Arterial Mediolysis Treated Successfully by Laparoscopic Partial Omentectomy

INTRODUCTION: Segmental arterial mediolysis (SAM) is a rare, non-atherosclerotic, non-inflammatory arteriopathy characterized by lysis of the arterial media, leading to aneurysm formation and possible rupture. Although visceral arteries are typically involved, SAM-induced omental bleeding is extremely uncommon. While transcatheter arterial embolization (TAE) has been reported, surgical resection offers both definitive hemostasis and histopathological confirmation.
CASE PRESENTATION: A 56-year-old man presented with upper abdominal pain without a history of trauma. Contrast-enhanced CT revealed a hematoma and fusiform dilation of an omental artery, suggesting omental hemorrhage. As he was hemodynamically stable, initial conservative management was chosen. However, a follow-up CT on day 7 demonstrated aneurysm enlargement, prompting laparoscopic partial omentectomy. Intraoperative findings included a 5-cm hematoma in the central omentum. Histopathological examination showed vacuolization of the tunica media and loss of the internal elastic lamina, confirming the diagnosis of SAM. The patient had an uneventful postoperative course and was discharged on the 3rd postoperative day.
CONCLUSIONS: This rare case of SAM-related omental bleeding was successfully treated with laparoscopic partial omentectomy. Tailored treatment strategies including laparoscopic surgery are essential for optimal outcomes in SAM.