DMSC1105 Outcome 2 Exam Prep - Gallbladder and Biliary Tree

What shape is the gallbladder?

Pear shaped

Is the gallbladder hollow? And what happens when it is empty of bile?

It is hollow! When empty of bile, the gallbladder walls will collapse and may touch.

Where is the gallbladder located?

In a small depression on the inferior aspect of the liver.

Where is the neck of the gallbladder found?

It is found in the intrahepatic sulci along with the main lobar fissure and middle hepatic vein.

What is the order of the path of bile in the gallbladder?

It goes from the lumen --> neck --> cystic duct --> CBD (where it meets up with the common hepatic duct)

When can we tell if the hepatic ducts have exited the liver helium?

When the left and right hepatic ducts join into the common hepatic duct.

What are the three main parts/sections of the gallbladder?

The fundus (most anterior and inferior part), body (most hollow and largest part) and the neck (where the body narrows and is fixed in place)

What section(s) of the gallbladder is mobile?

The body and the fundus

Can we see the gallbladder neck on ultrasound?

Not usually unless it is distended.

Why do we move the patient into multiple positions when imaging their gallbladder?

Because the gallbladder is mobile and so pathology could be hidden. We need to use gravity.

What part of the gallbladder is most anterior?

The fundus.

What is the gallbladder lumen lined with?

It is lined with a mucous membrane

What supplies the gallbladder lumen?

The cystic artery (a branch off of the right hepatic artery)

What are the three layers of the gallbladder wall?

The serosa, muscularis, and mucosa.

What is the purpose of the mucosa layer of the gallbladder and where is it located?

It is the most inner layer. It absorbs water from bile to make it more concentrated.

What is the purpose of the muscularis layer of the gallbladder and where is it located?

It is the middle layer and the muscle layer. It contracts (squeezes) to push bile out of the gallbladder.

What is the purpose of the serosa layer of the gallbladder and where is it located?

It is the most outer layer. It is the outer covering of the gallbladder that protects and supports the it.

What glands are present in the neck of the gallbladder?

Tubuloalveolar mucus glands.

What do the Tubuloalveolar mucus glands in the neck of the gallbladder do?

They produce mucus to protect the gallbladder lining from bile and to help bile move smoothly through the neck and cystic duct.

What is the hartmans pouch in the gallbladder?

Where there is a larger concentration of Tubuloalveolar mucus glands.

What happens when Tubuloalveolar mucus glands are inflamed?

They may produce tiny crystals that we can see on ultrasound.

Where is the hartmanns pouch of the gallbladder located? Does the whole population have them?

They are located mainly in the neck of the gallbladder. Not everyone has them. They are common locations for stones to be stuck.

What are heister valves in the gallbladder and where are they located?

They are one way valves in the cystic duct that allow bile to go into the CBD but not come backwards.

What are the Rokintansky Aschoff Sinuses in the gallbladder?

They are deep pouches in the mucosa. They form when the inner lining (mucosa) of the gallbladder pushes into the muscle layer of the gallbladder wall. Stones and things may hide in them.

What are the ducts of luschka in the gallbladder?

They often regress because we don't need them after birth but they can sometimes turn into a duct instead. They are small bile ducts that originate in the gallbladder fossa and connect to the gallbladder by the inferior right lobe of the liver.

What is the gallbladder fossa?

The gallbladder fossa is the indentation on the inferior surface of the liver that houses and anchors the gallbladder.

What is the gallbladder anatomical variant called Phrygian cap?

A fold at the fundus of the gallbladder but still a connection.

What is the gallbladder anatomical variant called Juntional fold?

A fold in the neck of the gallbladder but still a connection. We may not always see this since we cant always see the gallbladder neck.

What is the gallbladder anatomical variant called septate gallbladder? Can the septations still communicate?

There are two or more communicating gallbladder compartments that are separated by thin septations. Bile may still be able to get in and out, but it would be through small channels.

When can a junctional fold, phrygian gap, or septate gallbladder be an issue?

If there is a stone that cannot pass through.

What is a extremely mobile/ectopic/floating gallbladder? What conditions make this occur?

This could occur with too long ligaments or a loose peritoneum (serous membrane). This is because the peritoneum helps anchor the gallbladder in place. The hypermobility of the gallbladder could cause it to cut off its own blood supply via torsion.

What is gallbladder torsion?

gallbladder torsion occurs when the gallbladder rotates around the cystic duct and cystic artery.

Two different types of duplicated gallbladder anatomical variant?

They usually lay side by side and can either share a cystic duct or have two cystic ducts. This can be seen later on in utero and there are many variations.

What is the main function of the gallbladder?

To store bile that it received from the liver and concentrate it by removing electrolytes.

Why does the gallbladder concentrate the bile?

So that it is more efficient for use.

How and why is the gallbladder triggered?

It is triggered when food enters the duodenum. The duodenum secretes cholecystokinin, causing the gallbladder to contract and force bile through its ducts.

Where does the bile enter the duodeum at?

It carries its bile via the common bile duct to the pancreas where it meets the main pancreatic duct at the ampulla of vater and exits out of the sphincter of oddi.

What is gallbladder sludge and how does it appear?

It is concentrated bile that has been there too long and may turn into a stone. It is more hyperechoic.

How should the gallbladder walls and lumen appear?

The lumen should be anechoic and the walls should be hyperechoic.

What is the gallbladder Murphy sign?

When we press down on the area with the probe to see if there is tenderness. Pain = positive murphy sign.

How do we image the gallbladder? What position is our patient in?

Image the gallbladder with the patient in supine and decubitus. Erect or prone positions may be useful if trying to decipher if there is a mass.

Can the patient eat before a gallbladder or biliary tree exam?

They should be fasting for 6-8 hours so that the gallbladder is full of bile and not collapsed. And so that bowel glass is mainly eliminated to make it easier to see the ducts

How thin should the gallbladder walls be?

They should be less than 3mm wide.

What does the dependent portion of the gallbladder mean?

The dependent portion of the gallbladder is the lowest part at any given moment, where bile, sludge, and gallstones settle under the influence of gravity.

Can gallbladder folds appear and disappear?

If a gallbladder fold disappears/appears based on patient positioning, it is not a true anatomical variant.

How may the walls of the gallbladder appear if the patient is not fasting?

They may appear thinner since not under the pressure of a full lumen.

What if we cannot acquire a transverse image of the gallbladder completely round?

This is due to a not fully distended gallbladder. Try to find the roundest part.

How does the gallbladder lie when the patient is in a decubitus position? How would we change our imaging in transverse and sagittal?

The fundus will flop to the patients side due to gravity. We always need to image in transverse/sagittal to the ORGAN not to the body, so we may be trans on the organ but sagittal on the body (and vice versa)

Do we measure gallbladder wall thickness in a non-distended or contracted gallbladder?

No, because there is no pressure in the lumen so it will be inaccurate.

What is the biliary tree?

The system of bile ducts that transports bile between the liver, gallbladder, and small intestine.

If the portal vein is very very small, does a duct still travel with it?

Yes! There is always a duct with a portal vein.

When does the common bile duct become the common bile duct?

When the cystic duct and hepatic duct join together.

What is an MRCP (Magnetic Resonance Cholangiopancreatography) test?

Contrast is injected into the duodenum to see the sphincter of oddi. This allows us to see the biliary tree and will sometimes fill the gallbladder with contrast as well (the pressure from the contrast may push the valves backwards to allow it in).

Where do the hepatic ducts lie?

They are normally anterior to the portal bifurcation.

What does the common hepatic duct form from?

It forms from the joining of the right and left hepatic ducts.

Where is the dilation present when there is an obstruction?

The dilation will only be proximal to the obstruction.

How large can dilated ducts appear in comparison to the portals?

They can appear the same size as the portal veins.

Do we usually see the CBD? What does it likely mean if we see it?

Not usually unless it is dilated or we have an amazing vis patient.

Where is the intrahepatic duct located in relation to the hepatic artery and common bile duct?

The common hepatic duct is proximal to the hepatic artery. Then, the common bile duct is distal to the hepatic artery. We use the hepatic artery as our separator to know if we are looking at the common hepatic or the common bile duct.

Do we normally see the cystic duct?

Not usually unless it is dilated or we have an amazing vis patient.

What should the common bile duct measure at if the patient has not undergone a cholecystectomy? And what do we include in the measurement?

It should be 6mm or less. And we only measure the lumen, not the walls.

What should the common bile duct measure at if the patient has undergone a cholecystectomy?

less than 10mm. This is because the common bile duct takes on some of the gallbladders storage qualities since the gallbladder has been removed.

What happens to ducts and veins when they are near an artery?

Ducts and veins are very placid and so when they are up against an artery (which is very pressurized), they may collapse a bit and not show the full diameter.

Where are most duct variants found?

In the hepatic ducts. There are millions of different variants.

What position is best to see the common bile duct?

With the patient in decubitus.

What is the easiest way to locate the common bile duct?

Locate the main portal vein and you should be able to locate the CBD!

What is a trick for differentiating arteries from veins and ducts?

Turn on color doppler

Where can we find the intrhepatic ducts?

Inside the liver by the portal bifurcation.

What happens when a patient goes past 8hrs of fasting?

There may be excessive gas due to stomach rumbling

What do we do if a patient has not properly prepped for an exam?

Document it.

Where do we see the CBD in relation to the pancreas?

By the pancreas head.