Prince ……….

ABDOMINAL VISCERA FOR EACH PART YOU MUST KNOW: 1.SURFACE ANATOMY 2.RELATIONS 3.PERITONEAL COVERING 4.BLOOD SUPPLY 5.NERVE SUPPLY 6.LYMPHATIC DRAINAGE 7.SUPPORT (IN SOME PARTS)

SMALL INTESTINE DUODENUM: fixed part JEJUNUM & ILEUM: movable part (with mesentery)

JEJUNUM & ILEUM Length:Length: 6 meters (20 feet) Beginning:Beginning: duodenojejunal flexure Termination:Termination: ileocecal junction Embryological origin:Embryological origin: midgut Peritoneal fold:Peritoneal fold: mesentery of small intestine Arterial supply: superior mesentericArterial supply: jejunal & ileal branches of superior mesenteric Lymphatic drainage:superior mesentericLymphatic drainage: superior mesenteric lymph nodes Nerve supply:superior mesentericNerve supply: superior mesenteric plexus: sympathetic & parasympathetic (vagus)

MESENTERY OF SMALL INTESTINE Extent:Extent: from duodenojejunal flexure to ileocecal junction Formation:Formation: formed of 2 layers Free border (6 meters long):Free border (6 meters long): encloses jejunum & ileum Root (6 inches long, J-shaped):Root (6 inches long, J-shaped): crosses superficial to the following structures: 1.Third part of duodenum 2.Abdominal aorta 3.Inferior vena cava 4.Right psoas major 5.Right ureter

MESENTERY OF SMALL INTESTINE Shape:Shape: Fan-shaped with undulations Content of root:Content of root: superior mesenteric vessels Contents (structures between its 2 layers):Contents (structures between its 2 layers): 1.Jejunal vessels: 1.Jejunal vessels: form few arcades 2.Ileal vessels: 2.Ileal vessels: form many arcades 3.Mesenteric lymph nodes 4.Autonomic nerve fibers 5.Mesenteric fat

MESENTERY OF SMALL INTESTINE

JEJUNUM 1.Length: 1.Length: shorter (proximal 2/5) 2.Diameter: 2.Diameter: wider 3.Wall: 3.Wall: thicker (more numerous plicae circulares: circular folds of mucosa) 4.Appearance: 4.Appearance: more red in color (more vascular) 5.Vessels: 5.Vessels: less arcades, long terminal branches 6.Mesenteric fat: 6.Mesenteric fat: small amount near intestinal border 7.Aggregations of lymphoid tissue: 7.Aggregations of lymphoid tissue: few

ILEUM 1.Length: 1.Length: longer (distal 3/5) 2.Diameter: 2.Diameter: narrower 3.Wall: 3.Wall: thinner (less numerous plicae circulares: circular folds of mucosa) 4.Appearance: 4.Appearance: light red in color (less vascular) 5.Vessels: 5.Vessels: more arcades, short terminal branches 6.Mesenteric fat: 6.Mesenteric fat: large amount near intestinal border 7.Aggregations of lymphoid tissue: 7.Aggregations of lymphoid tissue: numerous (Peyer’s patches)

LARGE INTESTINE PARTS: 1.Cecum 2.Appendix 3.Ascending colon 4.Transverse colon 5.Descending colon 6.Sigmoid (pelvic) colon 7.Rectum 8.Anal canal Parts of large intestine in abdomen: 9.N.B.: Parts of large intestine in abdomen: from 1 to 5

LARGE INTESTINE CHARACTERISTICS: 1.Teniae coli: 1.Teniae coli: 3 longitudinal muscle bands 2.Sacculations (haustrations): 2.Sacculations (haustrations): teniae coli are shorter than large intestine 3.Appendices epiploicae: 3.Appendices epiploicae: short peritoneal fold filled with fat in rectum & anal canalN.B.: characteristics are present in all large intestine EXCEPT: in rectum & anal canal

LARGE INTESTINE Embryological origin:Embryological origin: 1.From midgut: 1.From midgut: cecum, appendix, ascending colon, right 2/3 of transverse colon 2.From hindgut: 2.From hindgut: left 1/3 of transverse colon, descending & sigmoid colon, rectum, upper half of anal canal Peritoneal fold:Peritoneal fold: 1.Appendix, transverse & sigmoid colon: 1.Appendix, transverse & sigmoid colon: have mesentery 2.Cecum: 2.Cecum: completely covered by peritoneum, but has no mesentery 3.Ascending & descending colon: 3.Ascending & descending colon: covered anteriorly & on the sides 4.Rectum & anal canal: 4.Rectum & anal canal: discussed later

LARGE INTESTINE Arterial supply:Arterial supply: 1.Midgut:superior mesenteric 1.Midgut: colic branches of superior mesenteric 2.Hindgut: inferior mesenteric Lymphatic drainage:Lymphatic drainage: 1.Midgut: superior mesenteric 1.Midgut: superior mesenteric lymph nodes 2.Hindgut: inferior mesenteric 2.Hindgut: inferior mesenteric lymph nodes Nerve supply:Nerve supply: 1.Superior mesenteric 1.Superior mesenteric plexus: sympathetic & parasympathetic (vagus) 2.Inferior mesenteric 2.Inferior mesenteric plexus: sympathetic & parasympathetic (pelvic splanchnic nerves)

LARGE INTESTINE SURFACE ANATOMY

APPENDIX Surface anatomy: Mc’Burney’s pointSurface anatomy: the base of appendix is marked by Mc’Burney’s point: A point at the junction of lateral 1/3 & medial 2/3 of a line traced from right anterior superior iliac spine to umbilicus Opening:Opening: at posteromedial aspect of cecum, 1 inch below ileo-cecal junction

APPENDIX Positions: (from most to least common)Positions: (from most to least common) 1.Retrocecal 1.Retrocecal: most common position 2.Pelvic 3.Subcecal 4.Preilieal 5.Postileal

CECUM, ASCENDING & DESCENDING COLON ANTERIOR RELATIONS:ANTERIOR RELATIONS: 1.Coils of small intestine 2.Greater omentum 3.Anterior abdominal wall

1: Iliohypogastric nerve; 2: Ilioinguinal nerve; 3: lateral cutaneous nerve of thigh 4: Femoral nerve; 5: Genitofemoral nerve; 6: Obturator nerve P.M.= psoas major; Q.L.=quadratus lumborum; I.=iliacus; T.A.= transversus abdominis Iliac crest

1: Iliohypogastric nerve; 2: Ilioinguinal nerve; 3: lateral cutaneous nerve of thigh 4: Femoral nerve; 5: Genitofemoral nerve; 6: Obturator nerve P.M.= psoas major; Q.L.=quadratus lumborum; I.=iliacus; T.A.= transversus abdominis

CECUM, ASCENDING & DESCENDING COLON POSTERIOR RELATIONS:POSTERIOR RELATIONS: Cecum:Cecum: psoas major, genitofemoral nerve, iliacus, lateral cutaneous nerve of thigh, femoral nerve Ascending colon:Ascending colon: iliacus, lateral cutaneous nerve of thigh, quadratus lumborum, ilioinguial nerve, iliohypogastric nerve, iliac crest, origin of transversus abdominis from lumbar fascia Descending colon: relations of cecum + relations of ascending colon + left kidneyDescending colon: relations of cecum + relations of ascending colon + left kidney

RELATIONS OF TRANSVERSE COLON

ANTERIOR:ANTERIOR: greater omentum, anterior abdominal wall POSTERIOR:POSTERIOR: 2 nd part of duodenum, head of pancreas, coils of small intestine SUPERIOR:SUPERIOR: liver, gall bladder, stomach INFERIOR:INFERIOR: coils of small intestine