The cecum (plural: ceca or cecums) is the first part of the large bowel and lies in the right lower quadrant of the abdomen.
Blind-ending sac of bowel that lies below the ileocecal valve, above which the large intestine continues as the ascending colon. The cecum measures 6 cm in length and can have a maximum diameter of 9 cm before it is considered abnormally enlarged. The vermiform appendix typically arises from the posteromedial surface, 2 cm inferior to the ileocecal valve .
The superior margin of the cecum is defined by the ileocecal ostium. Upper and lower flaps consisting of smooth muscle protrude into the lumen around the ostium forming the ileocecal valve . Its competence is often shown by the lack of contrast reflux into the terminal ileum on contrast enema studies.
- anterior: parietal peritoneum, anterior abdominal wall, and loops of small bowel
- posterior: iliacus muscle, psoas muscle, femoral nerve, lateral femoral cutaneous nerve, genitofemoral nerve and variably, the appendix
- medial: ileocecal valve and terminal ileum
- superior: ascending colon
- inferior: the lateral third of the inguinal ligament
- anterior and posterior cecal arteries from the colic artery, a branch of the ileocolic artery from the superior mesenteric artery
- run with corresponding arteries to the superior mesenteric vein, a tributary of the portal venous system
- lymphatic network runs parallel to the arterial supply, to paracolic lymph nodes, which drain to the superior mesenteric group
- sympathetic supply via the superior mesenteric plexus
- parasympathetic supply via fibers from the anterior and posterior vagal trunks
- subhepatic cecum: failure of the cecum to migrate to its typical position during midgut rotation in embryogenesis
- mobile cecum
- right colonic mesentery fails to fuse to the lateral peritoneum
- occurs in ~15% of the population
History and etymology
Cecum is short for the Latin term "intestinum cecum", which means blind gut.
- Appendix vermiformis
- Volvulus des Coecums
- peritoneal cavity
- portal venous system
- superior mesenteric artery (SMA)
- Colon ascendens
- coned caecum