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GI Tract Anatomy

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GI Tract Anatomy SHRI Video Training Series 2018 dx and forward Recorded 1/2020 Colorectal Introduction & Anatomy Presented by Lori Somers, RN 1 Iowa Cancer Registry 2020 Mouth GI Tract Pharynx Anatomy Esophagus Diaphragm Liver Stomach Gallbladder Pancreas Large Small Intestine Intestine (COLON) 2 Anal Canal 1 Colorectal Anatomy Primary Site ICD-O Codes for Colon and Rectum Transverse Hep. Flex C18.4 Splen. Flex C18.3 C18.5 Ascending Large Descending C18.2 Intestine, C18.6 NOS C18.9 Cecum C18.0 Sigmoid C18.7 Appendix C18.1 Rectum C20.9 Rectosigmoid C19.9 3 ILEOCECAL JUNCTION ILEUM Ileocecal sphincter Opening of appendix APPENDIX 4 2 Rectum, Rectosigmoid and Anus Rectosigmoid junction Sigmoid colon Peritoneal Rectum reflection Dentate line Anus 5 Anal verge Peritoneum: serous membrane lining the interior of the abdominal cavity and covers the abdominal organs. Rectum is “extraperitoneal” Rectum lies below the peritoneal reflection and outside of peritoneal cavity 6 3 Greater Omentum Liver Stomach Vessels Ligament Greater Omentum: (reflected upward) Gallbladder Greater Greater Omentum Omentum Transverse colon coils of jejunum Ascending Descending colon colon Appendix Cecum coils of ileum slide 9 slide 10 7 Mesentery (Mesenteries): folds of peritoneum- these attach the colon to the posterior abdominal wall. Visceral peritoneum: = Serosa covering of colon (organs) Parietal peritoneum: = Serosa covering of ABD cavity (body cavities) 8 4 Colon & Rectum Wall Anatomy Lumen Mucosa Submucosa Muscularis propria Subserosa Serosa Peritoneum 9 Layers of Colon Wall (Lumen of Colon) epithelium lamina MUCOSA propria muscularis mucosa SUBMUCOSA MUSCULARIS circular PROPRIA longitudinal SUBSEROSAL FAT SEROSA 10 (Visceral Peritoneum) slide 12 5 EOD Tumor Code 300 Code 400 • Invasion thru muscularis propria • Mesentery • Pericolic/perirectal fat • Subserosal tissue/subserosal fat invaded • Peritonealized pericolic/perirectal tissues invaded: • Non‐peritonealized • ANTERIOR/Lateral surfaces of: pericolic/perirectal tissues invaded: • Ascending colon • Descending colon • POSTERIOR SURFACE of: • Hepatic flexure • Ascending colon • Splenic flexure • Descending colon • Cecum • Hepatic flexure • Sigmoid Colon • Splenic flexure • Transverse Colon • MIDDLE 1/3 of Rectum • Rectosigmoid • Anterior surface • Rectum middle 1/3 11 • LOWER 1/3 of Rectum • Anterior surface Types of Polyps I Pedunculated Sessile (on a stalk) (flat) 12 Source: Abeloff et al: Clinical Oncology, third edition, Elsevier Churchill Livingstone, 2004 6 Types of Polyps II Tubular Tubulovillous Villous Head Stalk Muscularis mucosa Submucosa Muscularis propria 13 Source: A.T. Skarin, Atlas of Diagnostic Oncology, 2nd ed., Mosby Wolfe, 1996 14 7 Lymph Nodes Lymph Nodes named after artery and veins 15 Match Terms below to Letters, Colorectal Anatomy (a letter maybe used more than once) Appendix ____ G Anus ____ E Ascending Colon ____ Cecum ____ Descending Colon ____ F Hepatic Flexure ____ Ileum ____ D H Left colon ___ Rectum ____ Rectosigmoid ____ A Right colon ____ Sigmoid ____ Splenic Flexure ____ C I Transverse colon ____ B J Place an X on the spot to represent the Ileocecal K valve/junction. L 8 Match Terms below to Letters, Colorectal Anatomy (a letter maybe used more than once) Appendix __B__ G Anus _L___ E Ascending Colon __D__ Cecum __C__ Descending Colon __H__ F Hepatic Flexure __E__ RIGHT LEFT Ileum __A__ D H Left colon __H_ Rectum _K___ Rectosigmoid ___J_ X A Right colon _D___ Sigmoid __I__ Splenic Flexure __G__ C I Transverse colon __F__ B J Place an X on the spot to represent the Ileocecal K valve/junction. L Match Terms below to Letters, Colorectal Anatomy Which is the Distal end of (a letter maybe used more than once) the large bowel? Appendix __B__ G Which is the Proximal Anus _L___ E end? Ascending Colon __D__ Cecum __C__ If surgery removed a Descending Colon __H__ F segment of colon, from Hepatic Flexure __E__ the ascending colon to mid-transverse colon; Ileum __A__ D H Left colon __H_ which end of the surgical Rectum _K___ specimen is the distal Rectosigmoid ___J_ X A end? D or F ? Right colon _D___ This relates to surgical Sigmoid __I__ margins: Splenic Flexure __G__ C I D is the ______margin Transverse colon __F__ B F is the ______ margin J Place an X on the spot to Colon surgery: segment represent the Ileocecal K H to J is removed. What valve/junction. L is the Distal and Proximal margins? 9 Colon & Rectum Wall Anatomy Mucosa ___ Lumen Muscularis propria ____ Serosa ____ Submucosa ____ Subserosa ____ A B C D E Peritoneum WHAT is “outside” the Serosa layer? Colon & Rectum Wall Anatomy Mucosa _A__ Muscularis propria _C___ Lumen Serosa _E___ Submucosa __B__ Subserosa __D__ A B C D E Peritoneum Staging of colon cancer is based on spread of cancer from lumen through the bowel wall 10 Questions? Contact Info Lori Somers, RN Training & Quality Improvement State Health Registry of Iowa [email protected] 21 11.
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