Large Intestine Dr Anna L Kiss Department of

Large Intestine Dr. Anna L. Kiss Department of Anatomy, Histology and Embryology Semmelweis University Budapest 2018

Large intestine Left colic flexure Right colic flexure ascending colon descending colon Transverse colon sigmoid colon Coecum Rectum Appendix vermiformis Canalis

Vastagbél Tenia omentalis Haustra Plica semilunaris left colic flexure right colic flexure Tenia mesocolica ascending colon descending colon transverse colon Tenia libera Appendices epiploicae Sigmoid colon Coecum Mesoappendix Rectum Appendix vermiformis Canalis

Teniae Tenia mesocolica (hidden) mesocolon transversum plica semilunaris Tela muscularis haustrum Tenia libera (visible) Tenia omentalis (hidden) Appendix epiploica graeter omentum

Large Intestine from the outside and from the Inside

Chracterisitcs of the large intestine Plicae semilunares: tela muscularis, stratum circulare (inside) Teniae coli: tela muscularis, stratum longitudinale (outside) Haustra: outpouches between teniae and plicae semicirculares Appendices epiploicae (omentales): fatty pouches in the subserose layer

right colic flexure left colic flexure descending ascending colon tansvese colon caecum ileum sigmoid colon appendix rectum symphysis

A. mesenterica superior A. mesenterica sup. Middle colic a. Riolani arch right colic a. Arteriae jejunales Ileocolica a. coecal a. Arteriae ilei

A. mesenterica inferior Abdominal aorta Riolani arch left colic a. middle colic a. Inf. mesenteric a. A Sudeck’s point B Aa. sigmoidales sup. rectal a. A: not dangerous B: risk

ascendening colon Recesses of the coecum sup. Ileocoecal recess Ileocolic a. Plica semilunaris Ileum terminale Inf. ileocoecal recess A. coecalis ant. A. coecalis post. Mesoappendix appendicular a. Tenia libera Tenia mesocolica Appendix epiploica Coecum Tenia omentalis Appendix vermiformis

Recesses of the coecum Sup. ileocoecal recess Recessus intersigmoideus Inf. Ileocoecal recess

Ileocoecal transition Tunica muscularis et serosa Root of the mesentery Mesentery Plica semilunaris Ileocoecal valve (Bauhin-valve) Ileum terminale Frenulum Mesoappendix Ostium appendicularis Appendix vermiformis

Tipical pressure points in case of appendicitis

Position of the appendix Spina-umbilicus line (1) Retrocoecal position (e) anteroparietal position (b) Mc. Burney’s point (2) Lumbal position (d) Interspinal line (5) ant. sup. iliac spine (4) Lanz’s point (3) Ilioinguinal position (c) Pelvic position (a) Lig. inguinale (6)

Positions of the appendix Positio lumbalis (d) Positio retrocoecealis (d) Positio ilioinguinalis (c) Positio pelvina (a) Positio anteroparietalis (b)

Large Intestinal Mucosa Histologic Characteristics of Large Intestines as Compared to Small Intestines • lack of villi • deeper crypts • rich in goblet cells • absence of Paneth-cells • adipose tissue in • submucosa and subserosa • only single lymph nodes (solitary lymphatic follicles)

Wall of Large Intestines Epithelium of mucosa Tunica muscularis of mucosa Lamina propria (+ Lieberkühn’s crypts) Tela submucosa Tunica muscularis + serosa Tenia coli

Histology of the wall of the large intestine Lamina propria mucosae (+ Lieberkühn’s crypts Tela submucosa Epithelium mucosae Tunica muscularis mucosae

Wall of Large Intestines Mitotic cells (M) Lamina propria mucosae Muscularis mucosae Goblet cells

Appendix Vermiformis human vermiform process

Folliculi lymphatici Appendix vermiformis Tunica mucosa Tela submucosa Tunica muscularis + Serosa Lieberkühn’s crypts

Rectum L 3 Discus intervertebralis L 5 Colon sigmoideum S 3 Sacral flexure Ampulla recti Perineal flexure

Anatomical border Rectum (Ampulla recti) Ampulla recti Anorectal line (3 -4, 5 cm) Canalis + Anus Canalis Anus

Canalis, anal canal Colorecatal zone: above the anorectal junction: similar to rectum (simple columnar epithelium) Transitional zone: upper part: anal columns, columns of Morgani lower part or squamous part: no columns of Morgani

Canalis Lower part of the rectum: anal canal 1. ) zona columnaris: : columna anales: anal columns (longitudinal folds) mucosal folds, columns of Morgani: stratified non-keratinized squamous epithelium sinus anales, Morgagni-sinuses: epithelium: simple columnar 2. ) zona intermedia (haemorrhoidea), squamous part: no Morgagni-sinuses epithelium: stratified non-keratinized squamous connective tissue: sebaceous glands no hair follicles+ internal haemorrhoidal plexus sphincter ani internus: smooth muscle 3. ) zona cutanea: skin circumanal glands: apokrine modified sweet glands

Canalis linea dentata (pec

Histological and embryological border Ampulla recti Linea dentata, pectinea, mucocutanea (2 cm) Linea anocutanea (1 cm) Endoderm (Mucosa recti) Canalis Endoderma (Zona columnaris) Pecten analis Canalis Ectoderma (Zona haemorrhoidalis) Anus Ectoderma (Zona cutanea)

laevator ani

Canalis

Peritoneal relationship of the rectum Vesicorectal pouch Rectouterine pouch

Blood supply and venous drainaige of the rectum • sup. rectal art. (unpaired): inf. mesentric art. • middle rectal a. (paired): directly from the int. iliac art. • inf. rectalis art. (paired): int. pudendal art. (int. Iliac art. ) • sup. rectal vein (v. portae) • middle rectal vv (v. cava inf. ) • inf. Rectal v. (int. Pudendal v. ; v. cava inf. )

Blood supply of the rectum A. rectalis sup. (A. mesenterica inf. ) Plica transversalis recti sup. A. rectalis media (A. iliaca int. ) V. rectalis sup. M. obturator int. M. levator ani V. rectalis media V. pudenda int. A. rectalis inf. (A. pudenda int. ) M. sphincter ani ext. V. rectalis inf. Plexus venosus rectalis int. Canalis Plexus venosus rectalis ext.

Venae hepaticae Máj Venous dranaige o the rectum Inf. vena cava inf. mesenteric vein sup. rectal vein (unpaired; NO valves!) int. Iliac vein Middle rectal vein (paired; valves!) M. levator ani int. pudendal vein inf. rectal vein (paired; valves !)

Colon: simple cylindrical epithelium Anorectal Junction Transition: stratified columnar (cuboidal) epithelium Skin: stratified squamous keratinized epithelium Sphincter ani internus Lymphatic follicles

References Bruce M. Carlson (2004). Human Embryology and Developmental Biology, 3 rd edition, Saint Louis: Mosby. Richard Coico, Geoffrey Sunshine, Eli Benjamini (2003). Immunology: a short course. New York: Wiley-Liss. Abraham L. Kierszenbaum (2002). Histology and cell biology: an introduction to pathology. St. Louis: Mosby.