Accessory Middle Colic Artery Arising from the Splenic Artery—A Case Report—

Abstract

Background : The arterial supply to the splenic flexure of the colon derived from the left aspect of the superior mesenteric artery (SMA) is called accessory middle colic artery (accMCA). This variation has been reported in 34% of the population. However, few reports have described the anatomical variation of an accMCA originating from the splenic artery (SA).

Case presentation : A 71-year-old man with a complaint of appetite loss was referred to our hospital. Contrast-enhanced computed tomography (CT) scan revealed a hypovascular mass in the body of the pancreas. Additionally, an accMCA originating from the root of the SA was detected using 3D-CT reconstruction images, which also revealed that the tumor had invaded the accMCA and spleno-mesenteric confluence. The tumor abutment of the SMA and SA involved <180° of the circumference of the artery. Neoadjuvant therapy was initiated, followed by distal pancreatectomy with concomitant accMCA resection and wedge resection of the superior mesenteric vein. Postoperatively, the adequacy of blood flow to the colon was confirmed by indocyanine green fluorescence imaging. The patient's postoperative course was uneventful, and he was discharged on postoperative day 15.

Conclusion : An accMCA arising from the SA without the left branch of the MCA is very rare. We preoperatively diagnosed this variation using 3D-CT, and concomitant resection was safely performed with distal pancreatectomy for pancreatic cancer.