mesenteri

The mesentery is a continuous fold of peritoneum that attaches much of the small intestine to the posterior abdominal wall. It provides a conduit for blood vessels, nerves, and lymphatics and helps stabilize the intestines within the abdominal cavity while allowing some mobility.

Anatomy: The mesentery proper refers to a fan-shaped fold that suspends the ileum and jejunum from the left to the right side of the abdomen. It contains arteries, veins, lymphatic vessels, and nerves, along with adipose tissue. The mesocolon suspends portions of the colon. Collectively these structures form a continuous peritoneal sheet that connects the gut to the posterior body wall.

Development and concept: The mesentery arises from the dorsal and, in some regions, ventral parts of the embryonic gut’s peritoneal lining. Historically considered a collection of separate structures, recent anatomical research has described the mesentery as a single, continuous organ with a uniform tissue plane.

Function: The mesentery anchors the intestines, conduits vascular, nerve, and lymphatic supply, and houses fat that stores energy and participates in immune functions. It also plays a role in peritoneal fluid dynamics and in the spread or containment of intraperitoneal infections.

Clinical relevance: Mesenteric disease includes thromboembolic mesenteric ischemia, mesenteric panniculitis, and mesenteric inflammatory changes seen in Crohn’s disease. Surgical procedures such as bowel resection and mesenteric lymphadenectomy require careful handling of mesenteric vessels and tissue planes; understanding the mesentery as an organized organ informs techniques for dissections and anastomoses.

Name and scope: The term derives from Greek mesos ‘middle’ and enteron ‘intestine.’ While the small intestinal mesentery is best known, mesenteric attachments exist for various parts of the gastrointestinal tract and in many vertebrates, reflecting a shared developmental pattern.