Vascular Structures of the Right Colon: Incidence and Variations with Their Clinical Implications

Background and Aims: There is a demand for a better understanding of the vascular structures around the right colonic area. Although right hemicolectomy with the recent concept of meticulous lymph node dissection is a standardized procedure for malignant diseases among most surgeons, variations in the actual anatomical vascular are not well understood. The aim of the present review was to present a detailed overview of the vascular variation pertinent to the surgery for right colon cancer. Materials and Methods: Medical literature was searched for the articles highlighting the vascular variation relevant to the right colon cancer surgery. Results: Recently, there have been many detailed studies on applied surgical vascular anatomy based on cadaveric dissections, as well as radiological and intraoperative examinations to overcome misconceptions concerning the arterial supply and venous drainage to the right colon. Ileocolic artery and middle colic artery are consistently present in all patients arising from the superior mesenteric artery. Even though the ileocolic artery passes posterior to the superior mesenteric vein in most of the cases, in some cases courses anterior to the superior mesenteric artery. The right colic artery is inconsistently present ranging from 63% to 10% across different studies. Ileocolic vein and middle colic vein is always present, while the right colic vein is absent in 50% of patients. The gastrocolic trunk of Henle is present in 46%-100% patients across many studies with variation in the tributaries ranging from bipodal to tetrapodal. Commonly, it is found that the right colonic veins, including the right colic vein, middle colic vein, and superior right colic vein, share the confluence forming the gastrocolic trunk of Henle in a highly variable frequency and different forms. Conclusion: Understanding the incidence and variations of the vascular anatomy of right side colon is of crucial importance. Failure to recognize the variation during surgery can result in troublesome bleeding especially during minimal invasive surgery.