Transcript The Abdomen - University of Western Australia

The Abdomen
Stuart M Bunt
Functional Anatomy 212
Overview
Embryology Revision
 Foregut,
Midgut and Hindgut suspended by
the dorsal mesentary, initially straight

Ventral mesentary connects stomach and ant.
abd. wall, rest of gut free anteriorly

Mesentary supplies blood and nerves to gut
between layers of peritoneum

Complex adult layout due to 270o rotation
Blood Supply to Abdominal Organs
 Foregut
 Celiac
trunk
 Midgut
 Superior
artery
mesenteric
 Hindgut
 Inferior
artery
mesenteric
 Rectum
 Internal
iliac artery
(pudendal and rectal
arteries)
Stomach
 Variable
size and
shape, distensible
 J shaped related to
body form
 Lesser and greater
curvature
 gastroesophageal
junction
 fundus,cardiac part,
body, pyloric part
 pyloric antrum and
sphincter
 rugae and gastric
pits
Blood Supply of Stomach
Superior
Mesenteric
Artery
Territory
Inferior
mesenteric
artery
territory
Venous system
 Portal
Vein
 Splenic
vein
 inferior
mesenteric vein
 Superior
mesenteric vein
 Gastric veins
 Hepatic
Veins
Inf. Vena Cava
Anastomoses
Stomach rotates and distends
Front
Dorsal
Mesentary
Ventral
Mesentary
Back
Splenic
tissue
Epiploic
Foramen
Omentum
Omentum
Under the OMENTUM
The Peritoneal cavity is divided in two
Rotation of stomach forms the greater
omentum
(allows stomach distension and infection
control)

Omental bursa or Lesser sac is inside
omentum
(a potential space)

 Lesser
omentum runs from stomach to liver
(note free lower border above epiploic foramen
contains portal vein, hepatic artery and bile
duct
Mesenteries are important:-


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Paracolic gutters channel fuid
Stop herniation due to bipedal posture
Supply blood/nerves
Sensitive to stretch
Contain infection
Useful in surgery
On return some gut fuses with
posterior wall
Diaphragm
1
2
Duo.
Asc. Colon
1.lienorenal lig.
2.trans. mesocolon
3.mesentary proper
4.mes. of sig. colon
3
4
Rectum
Desc. Colon
Retro-peritoneal
Oesophagus
10 inches from pharynx to stomach
 narrow
 at cricoid cartilage
 where left bronchus crosses
 oesophageal hiatus in diaphragm
 mucous membrane folded (normally
collapsed)
 stratified squamous epithelium
 striated above smooth below
 trachea on right,
 lower aorta on left
 medial to L. lung, behind left atrium

Duodenum


first 12 inches of gut
four parts form C shape
 duodenal cap
 radiologically identified, ulcers form here
 mobile
 descending part
 pancreatic and bile ducts
 horizontal part
 crosses psoas, IVC and aorta
 crossed by mesentery, sup mesen. art.
 ascending part
Jejunum




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2/5ths of small intestine
gradual transition to
ileum
many small villi
increasing numbers of
lymph nodules
no submucosal glands
lacteals in each villus
columnar epithelium
Ileum
distal
3/5ths of intestine
narrower, thinner, less vascular,
slower,
 more fat and arterial arcades in
mesentery than jejunum.
Peyer’s patches of lymphoid tissue
Colon

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ascending colon
retroperitoneal
right colic or hepatic
flexure
transverse colon
(mesocolon)
droops towards pelvis?
left colic or splenic
flexure
descending colon
retroperitoneal
pelvic or sigmoid colon
S shaped
Colonoscopy
Barium
enema
outlines
structures
on X-rays
Appendix
The Liver





Largest Gland (one of
largest organs)
Right upper abdomen
under diaphragm
Grows as outgrowth
of gut plus mesoderm
Diaphragmatic
surface
Visceral surface
down and left
 related to stomach,
duodenum, r.
kidney, r. colonic
flexure
 bears gall bladder
Biliary System

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
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R and L Hepatic ducts
Common hepatic duct
Joined by cystic duct (to
gall bladder)
Forms bile duct
(common bile duct)
Gall Bladder
 body and fundus,
salts and water
absorbed
 store for bile,
released in response
to cholecystokinin
Pancreas
Pancreas
Head
in concavity of duodenum
body across vertebrae
tail reaches the spleen
pancreatic duct (+ accessory?)
ampulla
duodenal papilla
Spleen
The Spleen
 Lies
in left hypochondriac region
between gastric fundus and diaphragm
at level of 9th-10th rib (not normally
palpable)
 Soft, friable, highly vascular, dark
purple
 Diaphragmatic surface
convex and smooth facing diaphragm
 Visceral surface
gastric, renal, pancreatic and colic
impressions
The Spleen (2)
 Hilum
of spleen long fissure through
which vessels and nerves pass
 Suspended from stomach by
gastrolienal ligament (contains short
gastric and left gastro-epiploic branches
of spenic artery)
 Suspended from posterior abdominal
wall by lienorenal ligament
 Covered by adherent peritoneum
Relationship to the Spleen
Kidneys
In fat capsule
Suprarenal
glands
superiorly
Direct Arterial
and venous
supply
Kidney Internal Structure
Renal
pyramids
between renal
columns
 Renal Cortex
 Renal
papillae drain
into minor
calix
 Major calix
join to form
renal pelvis
 Ureter as
outlet

Kidneys External View
 Artery
- Vein - Ureter
Relationships of the Kidneys