ABDOMINAL AORTA

* It begins at the aortic opening in the diaphragm at level of T12 vertebra

as continuation for descending throracic aorta.
* It ends 2 cm below & to left to the umbilicus at level of lower border
of L4 vertebra by dividing into right & left common iliac arteries.
* Branches:
a) Single : Coeliac trunk (upper border of L1), sup. mesenteric artery
(lower border of L1), inf mesenteric artery (level of L3), median
sacral artery ( from back of bifurcation at level of L4).
b) Paired: right & left inferior phrenic , right & left middle supra-
renal, right & left. renal (L2 ), right & left gonadal (L3) & 4 pairs
of lumbar arteries.

Coeliac trunk Oesophageal

I. V. C opening of the
diaphragm
Rt. phrenic A.
Lt. phrenic a.

Rt. Supra- Oesophagus

renal gland
Lt. crus of diaph.
Rt. middle
Lt. supra- renal gland
supra- renal
Lt. middle
A.
supra- renal
Sup. A.
mesenteric
A. Lt. renal A.
Rt. renal A.
Lt. ureter

Inf. mesenteric A.
Rt. ureter
Lt. gonadal A.
Rt. gonadal A.
Rt. common iliac Lt. common iliac A.
A.
Rt. common iliac Lt. common iliac V.
V.
Median sacral A.
Median sacral V.

* Branches of Aorta *
* Anterior Relations: from above downwards.

1) Coeliac trunk.
2)Body of pancreas with the splenic vein, above the superior
mesenteric artery and left renal vein, below the superior
mesenteric artery.
3)Uncinate process of pancreas .
4)The 3rd part of duodenum separated from aorta by inferior
mesenteric artery .
5)Root of mesentery of small intestine containing superior
mesenteric artery .
6) Peritoneum of the posterior abdominal wall.
7) Coils of small intestine.

* Posterior Relations:
1- Bodies of the upper four lumbar vertebrae and intervening
discs with the anterior longitudinal ligament .
2- The left 3rd and 4th lumbar veins which cross behind the
aorta to end in the inferior vena cava.
* On the sides:
1) Azygos vein and cysterna chyli : on the right side above
L2 ( i.e structures passing in aortic opening in the
diaphragm).
2) Crus of diaphragm: on each side of its upper part .
3) Sympathetic chain: on left side of its lower part.
4) Inferior vena cava on the right side, below L2 vertebra.
5) The.4th part of duodenum on the left side, opposite L2
vertebra.
* N.B. The aorta is surrounded by networks of autonomic
nerves ganglia, lymph vessels and lymph nodes.
 Portal V. I.V.C.
Median arcuate ligament
Opening to
lesser sac Coeliac A. & its branches
Hepatic A.
Gastro-duod A. Splenic V.
1st part of
duodenum Body of pancrea

Bile duct Lt. renal V.

4th part of the

Head of duodenum & the
pancreas duodeno-jejunal
flexure
3rd part of
duodenum Inf. mesenteric A.

Rt. gonadal
A. Coils of small
intestine

Sup. mesenteric
vessels in root of
mesentery of small
Aorta
intestine
I.V.C.

* Relations of Aorta & I.V.C.*

 ARTERIAL SUPPLY OF GUT

1. COELIAC TRUNK
* It arises from front of aorta at level of upper border of LI, passes
forwards for 1/2 inch then it ends by dividing into 3 terminal
branches.
* It is the artery of foregut.
*On each side it is related to caeliac ganglion & a crus of diaphram.
* Anterior relations: it is related to cavity of lesser sac.
* Inferiorly it is related to upper border of body of pancreas.

Lt. hepatic A. Oesophageal opening of

diaphragm Oesophageal branch of
Rt. hepatic A.
Cystic a. Lt. gastric A.
Short gastric
a.a.
Hepatic A.
 Supraduodenal a.

Gastroduodenal
A.

Lt. gastroepiploic A.

Superior pancreatico-
duodenal A. Rt. gastroeiploic A.

* Coeliac Trunk; Branches *

* Branches:
a) Left gastric a. which gives oesophageal & gastric branches.
b) Splenic a.: Tortuous, runs above body of pancreas, gives
pancreatic branches, short gastric, Lt. gastroepiploic & splenic
branches.
 c) Hepatic a.: Passes in the free border of lesser omentun in front of
portal V. and on the Lt. side of C.B.D. It gives right gastric a.,
gastroduodenal a. (gives sup. panceatico-duodenal a. & Rt gastro-
epiplioc a.) and Rt & Lt. terminal branches to liver.
2. SUP. MESENTERIC ARTERY.
* It arises from front of aorta at level of lower border of Ll & ends in
the Rt. iliac fossa by anastomosing with ileo-colic a.
* It is the artery of midgut.
*Branches: Inf. pancreatico-duodenal a., jejunal & ileal branches, Rt.
colic a., middle colic a. & ileo-colic a.
* Relation: It arises behind body of pancreas on the left side of its V.
then both pass in front of Lt renal V., uncinate process of pancreas,
3rd part of duodenum, then enters the root of mesentery of small
intestine.
I.V.C. Aorta

Head of pancreas
Uncinate process of head of
pancreas
3rd part of
Duodenum
Inferior mesenteric V.
Rt. psoas major

Rt. gonadal A.

Rt. Ureter
Inferior mesenteric A.

Rt. genitor- Superior mesenteric V.

femoral N.
Superior mesenteric A.
 3. INF. MESENTERIC ARTERY.
* It arises from front of aorta at levle of L3 behind 3rd part of
duodenum.
* It ends by entering the pelvis, by crossing middle of Lt. common iliac
a, as sup. rectal a.
* It is the artery of hindgut.
* Branches: Sup. Lt. colic a., inf. Lt. colic arteries (sigmoid arteries).
sup. rectal a. (main arterial supply to rectum).
* N.B.: Anastomosis along the med. aspect of ascending & desceding
colon and mesenteric border of transverse colon, forms the marginal
artery which gives the vasa recta. The latter are the terminal arterial
branches to the colon .
• This marginal artery has a great surgical importance as it can
maintain the viability of a long segment of the colon after division of
a major colic branch.
• According to blood supply, the colon is divided to 4 surgical
segments:
1. 1st segment: include terminal 10 inches of ileum, caecum,
ascending colon, Rt. colic flexure & Rt. 1/3 of transverse colon.
2. 2nd segment: Middle 1/3 of transverse colon.
3. 3rd segment: Lt. 1/3 of transverse colon and descending colon.
4. 4th segment: Sigmoid colon.
* Lymphatic drainage of colon follows arterial supply to the
following lymph nodes in sequence:
1. Epicolic nodes on the bowel wall.
2. Paracolic nodes between the marginal artery and the bowel.
3. Intermediate nodes on the main vessels along the colic arteries.
4. Central nodes along the superior and inferior mesenteric vessels.
 SUPERIOR MESENTERIC
ARTERY Lt. colic
flexure
Lt. 1/3

Rt. colic Rt. 2/3

flexure

INFERIOR
MESENTERIC
ARTERY
Ascending Lower Lt. colic
branch arteries (Sigmoid
arteries)
Posterior
caecal a. Ileal branch

Appendiculara

Meso-
appendix
Anterior
caecal a.

Appendix

Ampulla of rectum

Middle rectal a. (from

internal iliac A.)

Inferior rectal a. (from

internal pudenal A.)

* Branches of Sup. & Inf. Mesenteric artery *

 Common Iliac Artery

• It begins at the level of L4 & ends at the level of lumbo-sacral inter-

vertebral disc by dividing into internal & external iliac arteries.

Aorta

Rt. psoas major

Lt. C.I.A.
Rt. testicular A.

Rt. external iliac. A.

Genital branch of
genitor-femora N.

Femoral N.

Vas deferens

Rt. ext. iliac V.

External Iliac Artery

* It begins at the level of lumbo-sacral disc & ends at the mid-inguinal
point to continue as femoral artery.
* Branches:
1. Deep circumflex iliac.
2. Inferior epigastric a.: passes med. below deep inguinal ring then
ascends upwards behind the inguinal canal on the med. side of
the ring.
 • It pierces fascia transversalis & ascends between it & rectus m.,
then passes in front of arcuate line to enter the rectus sheath to
end at the level of umbilicus by anastomosing with superior
epigastric artery.
• It gives pubic branch (which may be large to replace the
normal obturator artery (abnormal obturator a.) & cremastric
artery (supply cremastric m.).

Internal Iliac Artery

• It begins at the level of lumbo-sacral intervertebral disc as one of

2 terminal branches of common iliac artery.
• It ends at the upper border of greater sciatic foramen by dividing into
anterior & posterior divisions.
• Branches:
1. Ant. division: umbilical (its distal part form lat. umbilical lig.),
sup. vesical, inf. vesical in male or replaced by vaginal & uterine
in female, obturator, middle rectal and 2 terminal branches
(internal pudendal & inf. gluteal).
2. Post. division: iliolumbar, lat. sacral & sup. gluteal.
 Posterior division &
superior rectal A.

Internal iliac A.

Anterior division
Inferior gluteal
A. Internal
pudendal A.

Sacro- tuber.
lig. Obturator internus
muscle & fascia

White line (Origin of

levator ani)

Corpus cavernosus

Dorsal A. of penis

Deep A. of penis
Sacro-
spinous lig. Corpus
spongiosum

Urethera
Inf.
Rectal A. Scrotal
arteries A. of bulb

Scrotum

A. of bulb Crus of
penis

Bulb of
penis

Pudendal N.
Internal pudendal A.

N. to. Obturator
internus
Internal pudendal A.

Sacro- spinous
ligament