Anatomy of the Abdomen 2

Question 1

Which quadrants of the body does the liver lie in?

Answer 1

It lies within the right hypochondrium and extended into the epigastrium. Parts of the liver may lie within left hypochondrium

Question 2

What ribs protect the liver?

Answer 2

7-11

Question 3

Describe the perineum that surrounds the liver

Answer 3

Intraperitoneal

Question 4

Where does blood from the digestive system first pass?

Answer 4

Blood from the digestive system if first directed to the liver to be processed before it gets circulated round the body.

Question 5

What proportion of the body weight makes up the liver and how much oxygen does it use?

Answer 5

2.5%

20%

Question 6

What are the 6 functions of the liver?

Answer 6

1. Storage, metabolism and release of nutrients and some vitamins.
2. Detoxification and elimination of toxins, drugs and metabolites. Important for pharmacology.
3. Synthesis of proteins: albumin, clotting factors.
4. Synthesis and secretion of bile, important for lipid digestion and absorption. Extra bile is stored in the gall bladder.
5. Role in immune function and clearance of intestinally absorbed bacteria.
6. Removal of red blood cells. Kupfer cells – specialised macrophages in liver.

Question 7

What are the 2 surfaces and 4 lobes of the liver?

Answer 7

Surfaces
• Diaphragmatic surface
• Visceral surface

Gross anatomical lobes
• Right lobe – caudate and quadrate arise from right lobe
• Left lobe
• Caudate lobe
• Quadrate lobe
(Caudate and quadrate are described as arising from right lobe)

Functionally:
• Caudate lobe is an independent lobe.
• Quadrate lobe to be considered part of left lobe.

Question 8

What are the segments of the liver?

Answer 8

• 8 functional segments
• Based on distribution of portal venous branches
• Important for surgical resection surgery

Question 9

Label the segments of the liver

Answer 9

On image

Question 10

Where is the diaphragm and falciform ligament in relation to the liver

Answer 10

Diaphragm - Liver is located directly under diaphragm.

Falciform ligament - Double fold of peritoneum connecting liver to anterior abdominal wall. Divides left lobe into right lobe.

Question 11

Label the posterior surface of the liver

Answer 11

On image

Question 12

Describe the production and path of bile

Answer 12

The synthesised and secreted bile will be stored in the gall bladder or pass down into the duodenum where it will act to emulsify fats

The bile is transported to the duodenum via the common bile duct – receives bile from the cystic duct (from the gall bladder) or directly from the liver through the common hepatic duct. The common hepatic duct will divide into left and right hepatic duct

Right and left hepatic duct -> common hepatic duct -> joins cystic duct to form the common bile duct

The proper hepatic artery from the common hepatic artery divides into left and right hepatic arteries

Hepatic portal vein enters into the liver

Question 13

Label and name the function of the falciform ligament

Answer 13

Double fold of peritoneum connecting liver to anterior abdominal wall.

The falciform ligament divides as it ascends, one layer will split to the right and one to the left. The splitting is called the coronary ligaments of the liver. The coronary ligaments fuse as the triangular ligaments (right and left). This forms the bare area of the liver, which is in direct contact with the diaphragm.

Question 14

Label and name the function of the Round ligament / ligamentum teres

Answer 14

Remnant of umbilical vein
Carries oxygenated blood from placenta
Small paraumbilical veins may remain in substance of ligament

The round ligament is continuous with the ligamentum venosum

Question 15

Label and name the function of the Fissure for ligamentum venosum

Answer 15

Remnant of ductus venosus

Shuts umbilical blood directly into IVC

Question 16

Describe the prenatal circulation of the liver

Answer 16

• The umbilical vein brings oxygenated blood from the placenta and ascends into the liver, it bifurcates, one to supply the liver with oxygen, the rest goes to the heart so it can be pumped round the body via the ductus venosus.
• The ductus venosus will enter the inferior vena cava which enters the right atrium where blood is pumped through the fossa ovale into the left atrium, through the left ventricle and up through the aorta
• The ductus venosus will form the ligamentum venosum in adult life

Question 17

Label the ligaments on the liver and describe what the bare area is

Answer 17

Bare Area
No peritoneum on top surface of liver.

Fenced by ant. and post. coronary which meet as the left and right triangular ligament.

Results from massive embryonic growth of liver within ventral mesogastrium.

Question 18

What are the recesses of the liver?

Answer 18

• Areas where fluid can fill, during infection – something to look out for on CT scans and MRIs
• The gap between the diaphragm and the liver is called the subphrenic space
• The other cap is between the kidney and the liver called the hepatorenal pouch of Morrison (likely area where fluid will accumulate)
• Under the liver there is another cap called the subhepatic space
• These spaces are all continuous with each other.

Question 19

Describe the lesser omentum and its attachments

What arteries run in the lesser omentum?

Answer 19

Double ford of peritoneum that connects the inferior surface of the liver to the lesser curvature of the stomach and first part of duodenum
1. Hepatogastric ligament
2. Hepatoduodenal ligament
• The lesser omentum is attached from the lesser curvature of the stomach and the duodenum to the inferior surface of the liver
• The left and right gastric arteries will run between the lesser omentum to supply the stomach

Question 20

What is the portal triad?

What forms the opening into the lesser sac?

Answer 20

Common bile duct
Proper hepatic artery
Hepatic portal vein 
Vagus nerve
Lymphatics

Superior: Caudate process of liver
Inferior: 1st part of duodenum
Posterior: Inferior vena cava and right crus of diaphragm
Anterior: Portal triad (in free edge of lesser omentum)

Question 21

What is Pringle’s Manoeuvre?

Answer 21

• Haemostat used to clamp hepatoduodenal ligament.

* Stops blood flow through hepatic duodenal artery and portal vein. This is useful in surgical procedures.

Question 22

Describe the dual blood supply of the liver

Answer 22

The liver is supplied by two blood vessels: proper hepatic artery and hepatic portal vein

On image

Question 23

What organs supply blood to the liver for processing?

Answer 23

Alimentary canal
Spleen
Pancreas
Gallbladder

Question 24

What forms the hepatic portal vein and label the vessels

Answer 24

• The superior mesenteric vein will be bringing deoxygenated blood from the midgut.
• The splenic vein and superior mesenteric vein will unit to form the hepatic portal vein
• The inferior mesenteric vein (brings blood from the hindgut), usually enters the splenic vein. However in 1/3 of people the inferior mesenteric vein will also enter the hepatic portal vein

On image

Question 25

What is portal hypertension?

Answer 25

* Nodules impede blood flow, blood flow cant leave the spleen so the spleen will enlarge, as blood flow is impeded * Obstruction in liver increases pressure in hepatic portal vein (eg. Cirrhosis). * May cause enlargement of spleen * Collateral (alternative) pathways open up between portal and systemic venous systems. Portosystemic anastomoses. * Caput medusa of para-umbilical veins

Question 26

Describe and label the Portosystemic Anastomoses system

Answer 26

* Blood can either go into the portal system or can travel into the systemic Venus circulation to be pumped to the heart, so it doesn’t get processed by the liver * There are locations in the body where this occurs called portosystemic anastomoses * One area is the oesophageal veins, normally the oesophageal veins will enter the left gastric vein to be brought into the hepatic portal vein to liver. But blood can also trave through the oesophageal veins into the azygous vein and then enter into the systemic circulation * At the peri-umbilical region, blood normally enters the portal system via the para-umbilical veins (small vessels that remain open around the round ligament of the liver). The umbilical vein closes over but small veins do remain which brings blood to the portal system. So blood can either pass via these small veins or the epigastric veins into systemic circulation. If the portal system is blocked blood cant flow through the para-umbilical veins to the portal system, so blood flows through epigastric veins and they become dilated. * Anal canal – blood from the hindgut travels through the portal system via the inferior mesenteric vein and enters the splenic vein to form the portal vein OR blood can travel through the inferior rectal veins into the iliac veins and then up through the IVC. If there is portal hypotension so blood passes through the inferior rectal and middle rectal vein.

Question 27

Where is bile produced, stored and pathed?

Answer 27

* The liver produces more bile than we need to use, therefore it has to be stored * It will be stored in the gall bladder * In order to get to the gall bladder, the bile will trave through the right or left hepatic duct to enter into the common hepatic duct, it will then travel up the cystic duct through the neck of the gall bladder into the body. The fundus is an air filled sac. * The bile will then travel down the cystic duct and will travel inferiorly behind the duodenum to enter into the major duodenal papilla. * The main pancreatic duct fuses with the common bile duct to create a widening called the hepatopancreatic ampulla (of vater). This allows the enzymes to enter to duodenum.

Question 28

Describe gall stones What do they cause obstruction to? Where are they commonly found?

Answer 28

* Gall stones can cause obstruction to the biliary tree * Often at the hepatopancreatic ampulla, the cystic duct or the hartmanns pouch (infundibulum) * If the gall stones block the biliary tree it means bile can enter the blood system which causes jaundice * Pain from gall stones can be referred to the back of the shoulder. The diaphragm is innervated by phrenic nerves at C3, C4 and C5 (also correspond to the dermatomes of the shoulder region). So pain in the gall bladder can be felt in the shoulder.

Question 29

Where the pancreas in relation to the stomach, what plane does it lie in? Is the pancreas retroperitoneal? What are the exocrine and endocrine functions of the pancreas?

Answer 29

Location • Posterior to stomach. • Transpyloric plane passes through neck (L1). • Secondary retroperitoneal apart from tail (splenorenal ligament). Function Exocrine • Pancreatic juice: acinar cells. • Enters duodenum through main and accessory ducts. Endocrine • Glucagon and insulin: Pancreatic islets of Langerhans. • Enters blood.

Question 30

Describe the structure of the pancreas

Answer 30

On image

Question 31

What is the function of the duodenum

Answer 31

* Chyme from pyloric part of stomach. * Bile from liver and gallbladder via common bile duct. * Enzymes from pancreas via main and accessory pancreatic duct.

Question 32

Describe the divisions of the duodenum and its peritoneum

Answer 32

* First part of small intestine. * ‘C’-shaped structure. * Widest lumen of small intestine. * First 2-3 cm: intraperitoneal (hepatoduodenal ligament). * Remaining portion is retroperitoneal. * First part of small intestine. * ‘C’-shaped structure (related to pancreas). * Anatomical divided into four parts * first part / Superior * Second part / Descending * Third part / Inferior/ Horizontal * Fourth part / Ascending * First part (duodenal cap): intraperitoneal. * Distal portion is retroperitoneal.

Question 33

What is the 1st duodenal part referred to? Why is it easy to see on X-ray? What vessel an an ulcer in the 1st duodenal part cause? What clinical condition is common in the 2nd part of the duodenum? What openings are in the 2nd duodenal region?

Answer 33

First / Superior Part • Referred to as ampulla or duodenal cap • Shows very easily on x-ray because the inner lining of duodenal cap is smooth • Smooth wall • Common site of duodenal ulcers. If duodenal ulcer is at the posterior wall of the duodenum there is an artery that runes directly behind it called the gastroduodenal artery. If the ulcer ruptures through the posterior wall this vessel can haemorrhage o Clinical consequence, as gastroduodenal artery runs posteriorly. Second / Descending Part • Most common site for diverticula. • Opening of: o Hepatopancreatic ampulla major duodenal papilla (of vater).  Marks division of foregut and midgut  Consequence for neurovasculature. o Accessory pancreatic duct ->minor duodenal papilla

Question 34

Describe the anatomical relations of the 3rd and 4rd parts of the duodenum

Answer 34

Third / Horizontal / Inferior Part • Crossed by superior mesenteric artery and vein. Fourth / Ascending Part • Joins jejunum at duodenojejunal flexure • Held in place by ligament of Treitz

Question 35

Describe the Arterial Supply to Pancreas and Duodenum

Answer 35

* Supplied by the foregut and midgut * The pancreas is part of the foregut, so it mainly supplied by branches of the coeliac trunk. If there is a rupture in the splenic artery, it is a medical emergency. Coming of the left gastric artery we have the left gastroduodenal artery, this runs behind the duodenum. * The gastroduodenal artery will also give off the superior pancreaticoduodenal artery. * The major duodenal papilla is the location between the foregut and midgut, and therefore the distal region of these structures are supplied by the superior mesenteric artery. This gives of the inferior pancreaticoduodenal artery On image

Question 36

Describe the lymphatics of the duodenum

Answer 36

* Follows arteries superiorly from superior pancreaticoduodenal to gastroduodenal to coeliac nodes. * Follows arteries inferiorly from inferior pancreaticoduodenal to superior mesenteric nodes.

Question 37

Describe Whipple’s Procedure

Answer 37

• If there is cancer within the head of the pancreas, all of the related organs have to be removed. • Remove: o Head of pancreas o Duodenum o Gallbladder o Bile duct • Then the pylorus part of the stomach can be directly attached to the jejunum

Question 38

What is an Annular Pancreas?

Answer 38

* This is a cogential condition where the pancreas develops incorrectly and two ventricle buds of the pancreas wrap round the posterior and anterior aspect of the duodenum constricting it, so food cannot pass through. * This causes vomiting and reflux * Ventral pancreatic bud consists two components. * During development two parts migrate in different directions around the duodenum. * Constrict the duodenum and may result sin complete obstruction.

Question 39

What type of organ is the spleen? What ribs is it protected by? What quadrant is it located in? Describe its peritoneum What is its blood supply? Function (4)?

Answer 39

``` Structure • Lymphatic organ. • Protected by 9th – 11th ribs. • Left upper quadrant / left hypochondrium. • 1 inch thick • 3 inches wide • 5 inches long • 7 ounces • Intraperitoneal organ Blood supply: splenic vessels (artery and vein) which runs through the hilum and in splenorenal ligament Function • White cell proliferation. • Immune surveillance. • Filters and stores red blood cells and platelets. • Recycles iron and globin. ```

Question 40

What is Splenomegaly?

Answer 40

The size of the spleen varies depending on the blood flow to the organ, when it comes big it is called splenomegaly Move diagonally and superiorly to locate the spleen Can be 10x its normal size May be palpable in right iliac fossa Can treat with splenectomy.