Sigmoid Veins, Posterior View

Description

Arising from the venous plexus along the sigmoid colon, the sigmoid veins (venae sigmoideae) course superiorly and medially within the sigmoid mesocolon toward the inferior mesenteric vein. Posteriorly, their tributaries can be followed as they track alongside the sigmoid arteries, lying anterior to the posterior abdominal wall musculature and overlying retroperitoneal landmarks such as the ureters and common iliac vessels. More cranially, the inferior mesenteric vein ascends on the left, typically posterior to the pancreas, en route to the splenic vein and portal venous system. Posterior visualization of this territory matters when you are teaching or planning mobilization of the left colon, because the vascular pedicle is handled from a retroperitoneal perspective during medial-to-lateral dissection. Misidentification of the inferior mesenteric vein during laparoscopic sigmoid colectomy can lead to troublesome bleeding in a confined field, and traction near the root of the sigmoid mesocolon puts the left ureter and hypogastric nerves at risk. Small vessels, big consequences. For anatomy curricula, this plate supports instruction on hindgut venous drainage, portal-systemic relationships, and the layered arrangement of mesentery, retroperitoneum, and pelvic viscera in posterior approaches. It also suits colorectal surgery texts and operative atlases illustrating safe planes around the inferior mesenteric vessels during oncologic resection and lymphadenectomy. Anatomical accuracy verified by SciePro's Medical Advisory Board.