Anat

• Important structures in the Ileocecal Region include: Terminal Ileum, Ileocecal Junction, Ileocecal Valve
• Cecum is a blind pouch below the attachment of the ileum
• Appendix emanates from the blind end of the cecum
• Mesentery consists of 2 folds of peritoneum conveying blood vessels to and from the bowel
• The ileocecal region is a common pathologic area for malignancy
• Terminal Ileum is around 5 cm from the ileocecal junction in anatomy
• Contains Peyer’s patches and is removed in Right Hemicolectomy for tumors of the Right Colon
• Peyer’s patches are specialized lymphoid tissues found in the terminal ileum
• Function of Terminal Ileum includes storage and analysis of chyme, absorption of Vitamin B12
• Vitamin B12 is only absorbed in the terminal ileum and is necessary for the maturation of RBCs, synthesis of DNA, and normal nerve function
• Absorption flow of Vitamin B12 involves binding to intrinsic factor produced by the parietal cell in the stomach
• Ileocecal Junction is the point of attachment of the terminal ileum to the cecum
• Ileocecal Valve is a sphincter muscle valve critical in limiting reflux of colonic contents back into the ileum
• Approximately 2L of fluid enters the colon daily through the ileocecal valve
• Incompetent Ileocecal Valve can cause chyme to go back to the ileum and may lead to obstruction
• Appendectomy is the most common structure approached in emergency abdominal surgeries
• Most common emergency procedure for appendicitis
• Most common emergency procedure in emergency abdominal surgeries is for appendicitis
• During appendectomy, residents do not trace for the appendix but find the taenia coli as it ends with the appendix
• Different incision lines for appendectomy:

  • RLQ for males
  • Midline for females
• Cecum is a small, right lower quadrant monolithic structure adherent to the cecum
• Taenia coli converge at the base of the appendix and provide a complete longitudinal muscle coat for the large bowel
• Intussusception is the telescoping of the bowel into another segment of the bowel
• Most common cause of intussusception in adults is tumors (malignancy)
• Volvulus is the twisting of the bowel around its longitudinal axis
• Fossae of cecum are pouches formed in the ileocecal region by peritoneal folds
• Appendix lies in the right lower quadrant, emanates from the blind end of the cecum, and may be found retrocecally/subcecally in 63% of cases
• The appendix can be found on the left side if it is very long
• In acute appendicitis, lower left quadrant pain is atypical but possible
• The appendix can be found on the left side in cases of Situs Inversus, although this is very rare
• The vermiform appendix is wormlike and usually ranges from 1-30 cm in length
• The usual length of the vermiform appendix is 6-9 cm
• The function of the appendix is as an immunologic organ that actively participates in the secretion of immunoglobulins (IgA)
• The appendix is no longer considered a vestigial organ
• The appendicial artery can originate from the ileocolic artery (most common), posterior cecal artery (2nd most common), and anterior cecal artery
• Amyand's Hernia is a rare form of inguinal hernia where the appendix is included in the hernia sac
• The main etiologic factor of acute appendicitis is obstruction
• In adults, the most dominant cause of obstruction is fecal materials
• In the pediatric age group, the most dominant cause of obstruction is lymphoid hyperplasia
• Teens are more common to have appendicitis