Vasculature of the Abdomen Flashcards
Where does the aorta terminate?
L4 - bifurcates into right and left common iliac arteries
What structure can the aorta be classified as?
Large elastic artery
In descending order, what are the branches of the thoracic aorta?
- Mediastinal arteries
- Oesophageal arteries
- Pericardial arteries
- Superior phrenic arteries
- Intercostal and subcostal arteries
What are the first and second intercostal spaces supplied by?
A branch from the subclavian artery
Where does the abdominal aorta begin?
At the level of T12
In descending order, what are the branches of the abdominal aorta?
- Inferior phrenic arteries
- Coeliac trunk
- SMA
- Middle suprarenal arteries
- Renal arteries
- IMA
- Median sacral artery
- Lumbar arteries
Where does the coeliac trunk arise?
From the anterior aspect of the aorta at aortic hiatus of diaphragm –> level of T12
Where does the SMA arise?
Lower level of T1
Where does the IMA arise?
Arises anteriorly at L3
What does the coeliac trunk divide into?
3 major branches:
- Left gastric artery
- Splenic artery
- Common hepatic artery
What direction do the branches of the coeliac trunk go?
Left –> left gastric and splenic artery
Right –> common hepatic artery
What does the left gastric artery give rise to?
Ascends across the diaphragm, giving rise to oesophageal branches before continuing anteriorly along the lesser curvature of the stomach
What happens when the left gastric artery gets to the lesser curvature of the stomach?
It anastomoses with the right gastric artery
Where does the splenic artery run?
After arising, it travels left towards the spleen, running posterior to the stomach and along the superior margin of the pancreas.
During its course, where is the splenic artery contained?
Within the splenorenal ligament
Where doest the splenic artery terminate?
It terminates into five branches which supply the segments of the spleen.
As well as supplying the spleen, what else does the splenic artery give rise to?
- Left gastroepiploic
- Short gastrics
- Pancreatic branches
What does the left gastroepiploic supply? What does it anastomose with?
Greater curvature of the stomach
Anastomoses with the right gastroepiploic artery
What do the short gastrics supply?
The fundus of the stomach
What does the common hepatic artery branch into?
The proper hepatic and gastroduodenal arteries
Where does the proper hepatic artery run?
Ascends through the lesser omentum towards the liver
What does the proper hepatic artery give rise to?
- Right gastric
- Right and left hepatic
- Cystic
What does the right gastric artery supply?
Supplies the pylorus and lesser curvature of the stomach.
What does the right and left hepatic supply?
Divide inferior to the porta hepatis and supply their respective lobes of the liver.
What does the cystic artery supply?
Branch of the right hepatic artery – supplies the gall bladder.
What is the cystic artery a branch of?
Right hepatic artery
What is the gastroduodenal artery a branch of?
The common hepatic artery
Where does the gastroduodenal artery run?
Descends posterior to the superior portion of the duodenum
What are the branches of the gastroduodenal artery?
Right gastroepiploic and superior pancreaticoduodenal
What does the right gastroepiploic supply?
Supplies the greater curvature of the stomach. Found between the layers of the greater omentum, which it also supplies.
What does the superior pancreaticoduodenal supply?
Divides into an anterior and posterior branch, which supplies the head of the pancreas
What is the only organ to receive arterial supply from all three branches of the coeliac trunk? How is this achieved?
The stomach
Through a system of anastomoses along the greater (gastroepiploic arteries) and lesser (gastric arteries) curvatures.
What is the pancreaticoduodenal arcade?
A network of arteries that surround and supply the head of the pancreas.
What are the 2 main arteries of the pancreaticoduodenal arcade?
Each has an anterior and posterior branch, that anastomose (e.g. anterior to anterior) forming a ring structure:
- Superior pancreaticoduodenal
- Inferior pancreaticoduodenal
What is the superior pancreaticoduodenal a branch of?
The gastroduodenal artery
What is the inferior pancreaticoduodenal a branch of?
Branch of superior mesenteric artery (SMA).
What does the SMA supply?
The organs of the midgut (from the major duodenal papilla of the duodenum to the proximal 2/3 of the transverse colon)
Where does the SMA arise?
It arises anteriorly from the abdominal aorta at the level of the L1 vertebrae, immediately inferior to the origin of the coeliac trunk.
Where does the SMA run?
After arising from the abdominal aorta, the superior mesenteric artery descends down the posterior aspect of the abdomen
As the SMA descends, what is anterior to it?
Pyloric part of the stomach, splenic vein and neck of the pancreas.
As the SMA descends, what is posterior to it?
Left renal vein, uncinate process of the pancreas and inferior part of the duodenum
What is the only part of the pancreas that hook around the back of the SMA?
The uncinate process
What is the first branch of the SMA?
The inferior pancreaticoduodenal artery
What does the inferior pancreaticoduodenal artery form?
Anterior and posterior vessels
What do the vessels of the The inferior pancreaticoduodenal artery anastomose with? What does this network supply?
With branches of the superior pancreaticoduodenal artery (derived from the coeliac trunk).
This network supplies the inferior region of the head of the pancreas, the uncinate process, and the duodenum
What are the 4 major branches of the SMA?
- Inferior Pancreaticoduodenal Artery
- Jejunal and Ileal Arteries
- Middle and Right Colic Arteries
- Ileocolic Artery
Where do the jejunal and ileal arteries pass?
Between the layers of the mesentery and form anastomotic arcades – from which smaller, straight arteries (known as the “vasa recta”) arise to supply the organs
How does the jejunal and ileal blood supplies differ?
The jejunal blood supply is characterised by a smaller number of arterial arcades, but longer vasa recta. In contrast, the ileal blood supply is marked by more arterial arcades with shorter vasa recta.
Where does the middle and right colic arteries arise?
From right side of SMA to supply colon
What do the middle colic and right colic arteries supply?
Middle - supplies the transverse colon
Right - supplies the ascending colon
What does the IMA supply?
The organs of the hindgut (the distal 1/3 of the transverse colon, splenic flexure, descending colon, sigmoid colon and rectum)
Where does the IMA arise?
It arises at L3, near the inferior border of the duodenum
Describe the route of the IMA
Descends anteriorly to its parent vessel, before moving to the left side
What are the 3 major branches that arise from the IMA?
- Left colic artery
- Sigmoid artery
- Superior rectal artery
What does the left colic artery supply?
The distal 1/3 of the transverse colon and the descending colon.
What does the left colic artery divide into?
Ascending and descending branches
What does the ascending branch of the left colic supply?
It supplies the distal 1/3 of the transverse colon, and the upper aspect of the descending colon.
What does the descending branch of the left colic supply?
Moves inferiorly to supply the lower part of the descending colon.
What does the descending branch of the left colic anastomose with?
The superior sigmoid artery
What do the sigmoid branches of the IMA supply?
The descending colon and sigmoid colon
What does the superior rectal artery supply? What is it a continuation of?
The superior rectal artery is a continuation of the inferior mesenteric artery, supplying the rectum
Where does the superior rectal artery divide?
At S3
What does the superior rectal artery divide into?
Into two terminal branches – one supplying each side of the rectum
What are the 2 major anastomoses of the IMA?
Both involve a union with branches of SMA:
- Marginal artery (of Drummond)
- Arc of Riolan
What does the marginal artery form?
Forms a continuous arterial circle along the inner border of the colon
Straight vessels (vasa recta) arise from the artery to supply the colon
What is the marginal artery formed by?
It is formed by the union of several branches; the ileocolic, right colic and middle colic of the SMA and left colic and sigmoid branches of the IMA.
Where is the Arc of Riolan?
Anastomosis between the middle colic branch of SMA and the left colic branch of IMA
What are the branches of the abdominal aorta?
- 3 single anterior visceral branches (coeliac, SMA, IMA)
- 3 paired lateral visceral branches (suprarenal, renal, gonadal)
- 5 paired lateral abdominal wall branches (inferior phrenic, 4 lumbar)
What does the abdominal aorta supply?
It supplies all of the abdominal organs, and its terminal branches go on to supply the pelvis and lower limbs. It also supplies the undersurface of the diaphragm and parts of the abdominal wall.
What is the abdominal aorta accompanied by through the aortic opening of the diaphragm?
By the azygos vein and thoracic duct
Describe the position of the IVC compared to the abdominal aorta?
Abdominal aorta descends on the left of the IVC
Why are right-sided arteries of the abdominal aorta slightly longer than their left-sided equivalents?
Because it lies slightly to the left of the midline, and due to the presence of the IVC next to it, they have further to travel
What is upper duodenum supplied by?
Ant. and post . superior pancreaticoduodenal arteries
What is lower duodenum supplied by?
Ant. and post. inferior pancreaticoduodenal arteries
What separates the trachea from oesophagus in development?
The region of the foregut just caudal to the pharynx develops two longitudinal ridges called the tracheoesophageal folds that divide the tube ventrally into the trachea (and subsequent lung buds), and dorsally into the oesophagus.
