A dual blood supply serves the splenic flexure. At this critical point, the superior and inferior mesenteric arteries communicate through the marginal artery. This communication allows the left colon to receive blood from the superior mesenteric circulation after surgical ligation of the inferior mesenteric artery. Griffith’s cadaver studies showed that a critical point is located at the splenic flexure where the marginal artery is often small. Subsequent arterioradiographic studies by Meyers showed that the marginal artery might be absent or tenuous near the splenic flexure, making this area vulnerable to ischemia.