Dr. Ahmed Fathalla Ibrahim

ABDOMINAL VISCERAABDOMINAL VISCERA

FOR EACH PART YOU MUST KNOW:FOR EACH PART YOU MUST KNOW:1.1. SURFACE ANATOMYSURFACE ANATOMY2.2. RELATIONSRELATIONS3.3. PERITONEAL COVERINGPERITONEAL COVERING4.4. BLOOD SUPPLYBLOOD SUPPLY5.5. NERVE SUPPLYNERVE SUPPLY6.6. LYMPHATIC DRAINAGELYMPHATIC DRAINAGE7.7. SUPPORT (IN SOME PARTS)SUPPORT (IN SOME PARTS)

SMALL INTESTINESMALL INTESTINE

• DUODENUM: fixed part

• JEJUNUM & ILEUM: movable part (with mesentery)

JEJUNUM & ILEUMJEJUNUM & 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:Arterial supply: jejunal & ileal branches of superior superior

mesentericmesenteric• Lymphatic drainage:Lymphatic drainage: superior mesentericsuperior mesenteric lymph

nodes• Nerve supply:Nerve supply: superior mesentericsuperior mesenteric plexus:

sympathetic & parasympathetic (vagus)

MESENTERY OF SMALL INTESTINEMESENTERY 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:1.1. Third part of duodenumThird part of duodenum2.2. Abdominal aortaAbdominal aorta3.3. Inferior vena cavaInferior vena cava4.4. Right psoas majorRight psoas major5.5. Right ureterRight ureter

MESENTERY OF SMALL INTESTINEMESENTERY 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):

1.1. Jejunal vessels:Jejunal vessels: form few arcades

2.2. Ileal vessels:Ileal vessels: form many arcades

3.3. Mesenteric lymph nodesMesenteric lymph nodes

4.4. Autonomic nerve fibersAutonomic nerve fibers

5.5. Mesenteric fatMesenteric fat

MESENTERY OF SMALL INTESTINEMESENTERY OF SMALL INTESTINE

JEJUNUMJEJUNUM

1.1. Length:Length: shorter (proximal 2/5)2.2. Diameter:Diameter: wider3.3. Wall:Wall: thicker (more numerous plicae

circulares: circular folds of mucosa)4.4. Appearance:Appearance: more red in color (more

vascular)5.5. Vessels:Vessels: less arcades, long terminal

branches6.6. Mesenteric fat:Mesenteric fat: small amount near

intestinal border7.7. Aggregations of lymphoid tissue:Aggregations of lymphoid tissue: few

ILEUMILEUM1.1. Length:Length: longer (distal 3/5)2.2. Diameter:Diameter: narrower3.3. Wall:Wall: thinner (less numerous plicae

circulares: circular folds of mucosa)4.4. Appearance:Appearance: light red in color (less vascular)5.5. Vessels:Vessels: more arcades, short terminal

branches6.6. Mesenteric fat:Mesenteric fat: large amount near intestinal

border7.7. Aggregations of lymphoid tissue:Aggregations of lymphoid tissue: numerous

(Peyer’s patches)

LARGE INTESTINELARGE INTESTINEPARTS:1. Cecum2. Appendix3. Ascending colon4. Transverse colon5. Descending colon6. Sigmoid (pelvic) colon7. Rectum8. Anal canal9. N.B.: Parts of large intestine in abdomen:Parts of large intestine in abdomen:

from 1 to 5

LARGE INTESTINELARGE INTESTINE

CHARACTERISTICS:CHARACTERISTICS:

1.1. Teniae coli:Teniae coli: 3 longitudinal muscle bands

2.2. Sacculations (haustrations):Sacculations (haustrations): teniae coli are shorter than large intestine

3.3. Appendices epiploicae:Appendices epiploicae: short peritoneal fold filled with fat

• N.B.: characteristics are present in all large intestine EXCEPT: in rectum & anal in rectum & anal canalcanal

LARGE INTESTINELARGE INTESTINE• Embryological origin:Embryological origin:1.1. From midgut: From midgut: cecum, appendix, ascending colon,

right 2/3 of transverse colon2.2. From hindgut: From hindgut: left 1/3 of transverse colon,

descending & sigmoid colon, rectum, upper half of anal canal

• Peritoneal fold: Peritoneal fold: 1.1. Appendix, transverse & sigmoid colon:Appendix, transverse & sigmoid colon: have

mesentery2.2. Cecum:Cecum: completely covered by peritoneum, but has

no mesentery3.3. Ascending & descending colon:Ascending & descending colon: covered anteriorly

& on the sides4.4. Rectum & anal canal:Rectum & anal canal: discussed later

LARGE INTESTINELARGE INTESTINE• Arterial supply:Arterial supply: 1.1. Midgut:Midgut: colic branches of superior mesenteric superior mesenteric 2.2. Hindgut: inferior mesentericHindgut: inferior mesenteric• Lymphatic drainage:Lymphatic drainage: 1.1. Midgut: superior mesentericMidgut: superior mesenteric lymph nodes2.2. Hindgut: inferior mesenteric Hindgut: inferior mesenteric lymph nodes• Nerve supply:Nerve supply: 1.1. Superior mesentericSuperior mesenteric plexus: sympathetic &

parasympathetic (vagus)2.2. Inferior mesentericInferior mesenteric plexus: sympathetic &

parasympathetic (pelvic splanchnic nerves)

LARGE INTESTINELARGE INTESTINESURFACE ANATOMYSURFACE ANATOMY

APPENDIXAPPENDIX

• Surface anatomy:Surface anatomy: the base of appendix is marked by Mc’Burney’s Mc’Burney’s pointpoint: 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

APPENDIXAPPENDIX

• Positions: (from Positions: (from most to least most to least common)common)

1.1. RetrocecalRetrocecal: most common position

2.Pelvic

3.Subcecal

4.Preilieal

5.Postileal

CECUM, ASCENDING & CECUM, ASCENDING & DESCENDING COLONDESCENDING 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 thigh4: Femoral nerve; 5: Genitofemoral nerve; 6: Obturator nerveP.M.= psoas major; Q.L.=quadratus lumborum; I.=iliacus; T.A.= transversus abdominis

1

2

3 4

5

6

Iliac crest

1: Iliohypogastric nerve; 2: Ilioinguinal nerve; 3: lateral cutaneous nerve of thigh4: Femoral nerve; 5: Genitofemoral nerve; 6: Obturator nerveP.M.= psoas major; Q.L.=quadratus lumborum; I.=iliacus; T.A.= transversus abdominis

1

2

34

5

6

CECUM, ASCENDING & CECUM, ASCENDING & DESCENDING COLONDESCENDING 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 + Descending colon: relations of cecum + relations of ascending colon + left kidneyrelations of ascending colon + left kidney

RELATIONS OF RELATIONS OF TRANSVERSE COLONTRANSVERSE COLON

RELATIONS OF RELATIONS OF TRANSVERSE COLONTRANSVERSE COLON

• ANTERIOR:ANTERIOR: greater omentum, anterior abdominal wall

• POSTERIOR:POSTERIOR: 2nd part of duodenum, head of pancreas, coils of small intestine

• SUPERIOR:SUPERIOR: liver, gall bladder, stomach

• INFERIOR:INFERIOR: coils of small intestine