|
The mesentery is a fold of membranous tissue that arises from the posterior wall of the peritoneal cavity and attaches to the intestinal tract. Within it are the arteries and veins that supply the intestine. The term can be used narrowly to denote just the material that supplies the jejunum and ileum of the small intestine, or broadly to include the right, left and transverse mesocolon, mesoappendix, mesosigmoid and mesorectum. The human mesentery, also called the mesenteric organ, mainly comprises the small intestinal mesentery, the right, left and transverse mesocolon, mesosigmoid and mesorectum. Conventional teaching has described the mesocolon as a fragmented structure; the small intestinal mesentery, transverse and sigmoid mesocolon all terminate at their insertion into the posterior abdominal wall.〔 Recent advances in gastrointestinal anatomy have demonstrated that the mesenteric organ is actually a single, continuous structure that reaches from the duodenojejunal flexure to the level of the distal mesorectum. This simpler concept has been shown to have significant implications.〔 ==Structure== Contemporary characterizations of mesenteric anatomy revealed several novel anatomical findings not previously documented. In 2012, the first prospective observational study of the mesocolon was undertaken.〔 109 patients undergoing open, elective, total abdominal colectomy were studied. Anatomical observations were recorded during the surgery and on the post-operative specimens. These observations included: *the mesocolon is continuous from ileocaecal to rectosigmoid level; *a mesenteric confluence occurs at the ileocaecal and rectosigmoid junction as well as at the hepatic and splenic flexures; *each flexure (and ileocaecal junction) is a complex of peritoneal and omental attachments to the colon centred on a mesenteric confluence; *the proximal rectum originates at the confluence of the mesorectum and mesosigmoid; *a plane occupied by perinephric fascia separates the entire apposed small intestinal mesentery and mesocolon from the retroperitoneum. Deep in the pelvis, this fascia coalesces to give rise to presacral fascia.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「mesentery」の詳細全文を読む スポンサード リンク
|