Mistaken Identity: Superior Mesenteric Vein Syndrome Presenting as Superior Mesenteric Artery Syndrome.

Superior mesenteric artery syndrome is a rare condition where the third portion of the duodenum becomes compressed between the superior mesenteric artery and the aorta. A 60-year-old woman presented with abdominal pain, nausea, and vomiting. Initial imaging was concerning for obstruction of the duodenum between the level of the aorta and the superior mesenteric vein. The patient was taken for esophagogastroduodenoscopy, which showed extrinsic compression of the duodenum with a visible pulsatile mass causing proximal dilation. She subsequently underwent robotic-assisted laparoscopic diagnostic laparoscopy, lysis of small bowel adhesions, and duodenojejunostomy proximal to the location of the obstruction.