Case 10- imaging and microanatomy

Question 1

Biliary colic

Answer 1

Pain- RUQ pain or epigastric pain. Pain is usually after eating and at night. It radiates to the back
Symptoms- Nausea and vomiting
Cause- Gallstones causing obstruction or passing through the cystic duct

Question 2

Acute cholecystitis

Answer 2

Pain- RUQ pain or epigastric pain
Symptoms- nausea and vomiting. Increased white cell count. Local peritonism (inflammation of the peritoneum)
Cause- Impacted stone in the neck of the gallbladder or cystic duct causing inflammation and ischaemia. Inflammation of the gallbladder

Question 3

Acute cholangitis

Answer 3

Pain- RUQ pain or epigastric pain
Symptoms- nausea and vomiting. Fever/rigors. Raised white blood cells, jaundice. Decreased blood pressure. Delirium
Cause- bacterial infection of the obstructed biliary tree

Question 4

Pancreatitis

Answer 4

Pain- RUQ pain or epigastric pain, can radiate to the back
Symptoms- nausea and vomiting, fever, increased heart rate, increased serum amylase or lipase
Cause- Gallstones can obstruct the outflow of the pancreatic duct. Enzymes are released which digest the tissue

Question 5

Diagnosing biliary colic

Answer 5

Ultrasound- look for calculi and assess size of the common bile duct

Question 6

Diagnosing acute cholecystitis

Answer 6

Ultrasound- look for calculi, thickened gallbladder, surrounding fluid

Question 7

Diagnosing acute cholangitis

Answer 7

Ultrasound- look for calculi in the CBD, biliary dilation and thickening. Used to assess secondary effects on the biliary tree
MRCP/ERCP- visualise the stone and remover it

Question 8

Diagnosing pancreatitis

Answer 8

Blood tests- raised amylase and lipase
CT- can confirm diagnosis and show complications like pseudocysts or necrosis
Ultrasound- Calculi present

Question 9

What test do you always perform when you are worried about the foregut

Answer 9

A liver function test

Question 10

Pseudocyst

Answer 10

Occur after 4 weeks and are capsulated pancreatic fluid, they are not lined with epithelium so they are not a true cysts. The necrosis is due to inflammation, it forms walled of collections after a few weeks.

Question 11

Magnetic resonance cholangiopancreatography (MRCP) Pro’s and cons

Answer 11

Pro’s- no ionising radiation, no contrast required, good soft tissue images
Con’s- contraindicated with metallic implants, claustrophobic

Question 12

Endoscope retrograde cholangiopancreatography (ERCP)

Answer 12

You pass an endoscope into the duodenum, enter the ampulla of Vater. Inject contrast media into the CBD (common bile duct). You then take real time images of the biliary tree. You can also remove stones, stent the duct and take biopsies.
• Pro’s- diagnosis and intervention in one.
• Con’s- risk of pancreatitis, cholangitis, bleeding and perforation. Radiation risk. Contrast is needed.

Question 13

Diagnosing Cirrhosis and risk factors

Answer 13

Risk factors- alcohol excess, viral hepatitis, autoimmune hepatitis, NASH (non-alcoholic fatty liver disease).
Imaging- ultrasound, elastography

Question 14

Diagnosing Hepato cellular carcinoma (primary liver cancer)

Answer 14

Risk factors- chronic liver disease
Imaging- Ultrasound, blood tests to assess for AFP (Alpha fetoprotein). CT to assess for local and distant metastasis and spread of cancer

Question 15

Diagnosing secondary liver cancer and cause

Answer 15

Risk factors- Cholorectal, gastric, pancreatic, breast, lung and eye cancer.
Imaging- Ultrasound, CT or MRI. Dependent on specific patient circumstances

Question 16

Most common causes of secondary liver cancer

Answer 16

Colorectal, breast, lung and eye cancer

Question 17

Elastography

Answer 17

A type of ultrasound that is used to assess for liver stiffness.
• <2.5-7 mild fibrosis
• 7-9.5 moderate fibrosis
• 9.5-12.5 severe fibrosis
• >12.5 cirrhosis

Question 18

How to divide the liver up

Answer 18

The Liver has 4 lobes, the lobes can be divided up into lobular structures. Within the lobules you have 4 different cell types

Question 19

Where is bile produced

Answer 19

Within the hepatocytes

Question 20

The capillaries within the liver

Answer 20

The Sinusoids

Question 21

How the portal triad travels through the liver

Answer 21

The portal triad divides into branches, but the three vessels stay together throughout the liver in bundles. These bundles will still be called portal triads.

Question 22

Roles of the hepatocytes

Answer 22

• Protein synthesis
• Protein storage
• Transformation of carbohydrates
• Synthesis of cholesterol, bile salts and phospholipids
• Detoxification, modification, and excretion of exogenous and endogenous substances
• Initiation of formation and secretion of bile

Question 23

What enters the hepatocytes

Answer 23

• Hepatic artery- oxygen, nutrients and circulating drugs.

* Hepatic portal vein- food, drugs, toxins and recycled bile salt.

Question 24

What leaves the Hepatpcytes?

Answer 24

• Hepatic vein- metabolites, glucose

* Bile- metabolites, bile salts

Question 25

Structure of the lobules

Answer 25

The lobules are separated with a border of connective tissue. At the different corners of the lobule you have the portal triad’s.

Question 26

How blood travels through the lobule

Answer 26

The blood from the portal vein and hepatic arteries travel in the sinusoids to enter the central vein. The sinusoids are between the hepatocytes. The central vein is in the centre of the lobule. They return the blood to circulation via the hepatic veins.

Question 27

Structures within the hepatic lobule

Answer 27

Portal triads, Sinusoids, Central vein, Hepatocytes (arranged as cords) and the Bile canaliculi.

Question 28

What is exchanged at the hepatocytes

Answer 28

They take the toxins and nutrients up and release metabolites and glucose

Question 29

How bile moves through the liver

Answer 29

Bile is produces from the hepatocytes drains into the bile canniculi and then into the bile ducts

Question 30

The 4 cell types in the lobule

Answer 30

• Hepatocytes
• Kupffer cells (Macrophages)
• Stellate cells (Perisinusoidal/Ito)
• Sinusoid endothelial cells.

Question 31

Hepatocyte structure

Answer 31

Linked by cell junctions in cell plates. They contain a cytoplasmic glycogen store which they can then break down and release as glucose. They have lots of endoplasmic reticulum for biosynthesis. The cell surface is in contact with bile canaliculi, so that the bile can drain directly into them.

Question 32

The space of Disse

Answer 32

The space between the Hepatocyte’s and endothelial cells

Question 33

Hepatic acinus

Answer 33

A different way to describe the structure of the liver. A more functional description

Question 34

Hepatic acinus structure

Answer 34

A combination of two hepatic lobules, there are two central veins which are surrounded by multiple portal triads. A line is drawn between the central veins. The acinus is the triangle between the 2 central veins and the closest portal triad

Question 35

Zones of the hepatic acinus

Answer 35

You draw rings around the central vein. The inner zone is closest to the central vein, then the middle zone and outer zone

Question 36

Hepatic acinus- the outer zone

Answer 36

High in oxygen from the hepatic artery. Contains the hepatocytes which perform Glycogen and protein synthesis. So, there will be high nutrients in the cell.

Question 37

Hepatic acinus- the middle zone

Answer 37

Transition between the function of the hepatocytes in the outer zone (metabolism) and inner zone (detoxification).

Question 38

Hepatic acinus- The inner zone

Answer 38

High levels of metabolic waste. Contains the hepatocytes which undergo oxygen detoxification. It is the most vulnerable to damage. Low levels of oxygen.

Question 39

Function of the space of disse

Answer 39

The gap between the sinusoid epithelium and hepatocytes. Allows movement of blood across it, it contains fibroblasts. There are gaps between the sinusoid epithelium (fenestrated epithelium) which allows the blood through into the space. Molecules can now be exchanged between the hepatocytes and the blood.

Question 40

Space of disse pathology

Answer 40

Fibroblast proliferation in disease can lead to portal hypertension as the sinusoid is narrowed.

Question 41

Liver fibrosis

Answer 41

When the hepatocytes are damaged the stellate cells are activated, there is also fibroblast proliferation. The stellate cells produce a scar matrix which further narrows the sinusoid.

Question 42

Cirrhosis- damage to the liver

Answer 42

You get liver fibrosis and the accumulation of lipids in the Liver. It is characterised by death and steatosis (lipid retention) of hepatocytes. Can be caused by alcohol, hepatitis and obstruction of the portal triad. Hepatocytes can regenerate but there is also destruction in the architecture of the connects of the hepatocytes. The is due to fibroblast proliferation and scar matrix formation. This will effect the sinusoids, blood vessels and bile ducts.