Pancreaticoduodenal Arcade Aneurysm Secondary to Dissection of the Superior Mesenteric Artery: A Case Report.

Pancreaticoduodenal aneurysms are commonly associated with narrowing of the celiac artery, although involvement of the superior mesenteric artery (SMA) is rare. A 77-year-old man presented with a 5-day history of abdominal and back pain. Contrast-enhanced computed tomography revealed hemorrhagic ascites, a pancreatic arcade aneurysm, and dissection of the SMA. Endovascular embolization was performed using metallic coils. Follow-up imaging demonstrated isolation of the aneurysm and improvement in the shrunken true lumen of the dissected SMA. This case suggests that narrowing of the SMA may alter blood flow in the pancreatic arcade and contribute to aneurysm formation.