Anat

• Important structures in the Ileocecal Region include: Terminal Ileum, Ileocecal Junction, Ileocecal Valve, Cecum, Taenia Coli, Intussusception, Volvulus, and Fossae of Cecum
• The Cecum is a blind pouch below the attachment of the ileum
• The Appendix emanates from the blind end of the cecum
• The Mesentery consists of 2 folds of peritoneum that convey blood vessels to and from the bowel
• The ileocecal region is a common pathologic area for malignancy
• The Terminal Ileum is around 5 cm from the ileocecal junction in anatomy
• In surgical practice, it is typically around 10 cm away
• The Terminal Ileum contains Peyer's patches
• Peyer's patches are specialized lymphoid tissues found largely in the terminal ileum in the submucosal layer
• Peyer's patches become inflamed during infection and stress
• Peyer's patches are absent in the upper 2/3 of the jejunum
• Peyer's patches are best marked in younger individuals and disappear as one becomes older
• The Terminal Ileum is responsible for the storage and analysis of chyme as it awaits passage into the colon
• Chyme is sieved/sterilized in the terminal ileum by the Peyer's patches for any potentially dangerous pathogens
• The Terminal Ileum is where absorption of Vitamin B12 occurs
• Vitamin B12 is mainly necessary for the maturation of RBCs, synthesis of DNA, and normal nerve function
• Vitamin B12 binds to intrinsic factor produced by the parietal cell in the stomach for absorption
• Ingestion of food containing Vitamin B12 leads to its absorption in the terminal ileum
• If the Terminal Ileum is removed/resected, there is a lack of Vitamin B12 absorption, requiring lifelong oral supplementation
• The Ileocecal Junction is the point of attachment of the terminal ileum to the cecum
• It is the meeting point of the small and large bowels
• The Ileocecal Valve, also known as Ileal papilla, Tulp's valve, or Bauhin's valve, is a sphincter muscle valve critical in limiting reflux of colonic contents back into the ileum
• It allows movement of chyme into the colon and prevents colonic contents from going back to the terminal ileum
• Around 2L of fluid enters the colon daily through the ileocecal valve
• Incompetent Ileocecal Valve can lead to chyme going back to the ileum, obstruction, and proliferation of bacteria
• Appendectomy is the most common emergency procedure for appendicitis
• Appendectomy involves the removal of the appendix
• Figure 7 shows different procedures for appendectomy, including suppurative appendix and the presence of whitish deposits
• Most common emergency procedure: Appendicitis
• Appendix is a small, right lower quadrant monolithic structure adherent to the cecum
• During appendectomy, residents find the taenia coli as it ends with the appendix, instead of tracing for the appendix
• Different from colonoscopy, small incisions in the tummy are made, trocars with a camera are inserted to view the intraabdominal region without doing an incision
• Cecum is a blind pouch found on the right iliac fossa, below the attachment of the ileocecal valve
• Cecum is not fixed posteriorly to the retroperitoneum, it dangles there, which can lead to atypical pain presentations
• Retroperitoneal structures mnemonic: PUKE DADA - Pancreas, Descending colon, Ureter, Adrenals, Kidneys, Duodenum, Esophagus, Ascending colon
• Intimate structures with the cecum should be carefully dissected to avoid damage, especially in cancer cases
• Intussusception is the telescoping of the bowel into another segment of the bowel, with different types depending on the segments involved
• Most common cause of intussusception in adults is tumors (malignancy), while in children it is infection or inflammation of Peyer’s patches
• Volvulus is the twisting of the bowel around its mesentery, which can lead to gangrene if not corrected
• Fossae of cecum are pouches formed in the ileocecal region by peritoneal folds, significant during appendectomy procedures as the appendix may occupy any one of them