Biliary System Flashcards by Amber Newbigging

At what level does the biliary tree begin?

Level of the lobules at the bile canailculi

How well did you know this?

Not at all

Perfectly

Where are the bile canailculi located?

B/w hepatocytes within the interconnecting network

How well did you know this?

Not at all

Perfectly

How does the microscopic canailculi form the lobular bile ducts?

Anastomose

How well did you know this?

Not at all

Perfectly

How are the right and left bile ducts formed?

By the union of multiple lobular bile ducts

How well did you know this?

Not at all

Perfectly

At what level do the right and left hepatic ducts join to form the CHDs?

Porta hepatis

How well did you know this?

Not at all

Perfectly

Describe the position of the CHD

Anterior to the portal vein

Anterior and lateral to the RHA

How well did you know this?

Not at all

Perfectly

Where does the CBD travel?

Along the free edge of the lesser omentum

How well did you know this?

Not at all

Perfectly

What is the size of the CHD?

4mm in diameter

How well did you know this?

Not at all

Perfectly

What is the length of the CHD determined by?

The insertion point

How well did you know this?

Not at all

Perfectly

The CHD joins the cystic duct forming what?

CBD

How well did you know this?

Not at all

Perfectly

Describe the position of the CBD

Anterior and lateral to the MPV

How well did you know this?

Not at all

Perfectly

What are the normal diameter ranges for the CBD?

Up to 4mm - but varies with age and surgery

Add 1mm for every decade of life after 50years of age

Up to 10mm in post cholecystectomy pt

How well did you know this?

Not at all

Perfectly

What ligament does the CBD travel through?

Hepatoduodenal ligament

How well did you know this?

Not at all

Perfectly

What is the Mickey Mouse appearance?

Cross sections through the CBD, HA and MPV

Refer to page 3

How well did you know this?

Not at all

Perfectly

How many segments is the CBD divides into?

How well did you know this?

Not at all

Perfectly

What structure are the segments of the CBD relating its position to?

Duodenum

How well did you know this?

Not at all

Perfectly

What are the 4 segments of the CBD?

1st part (supraduodenal)
2nd part (retroduodenal)
3rd part (infraduodenal)
4th part (intraduodenal)

How well did you know this?

Not at all

Perfectly

What does the CBD insert into?

Ampulla of vater

How well did you know this?

Not at all

Perfectly

What regulates the flow of bile?

Sphincter of Oddi

How well did you know this?

Not at all

Perfectly

What segment is the narrowest part of the extra-hepatic biliary system?

4th part

How well did you know this?

Not at all

Perfectly

About how many cm does the cystic duct join the hepatic duct above the duodenum?

1-2cm

How well did you know this?

Not at all

Perfectly

What part of the GB does the cystic duct arise from?

Neck

How well did you know this?

Not at all

Perfectly

What is the shape and size of the GB?

3mm diameter

4cm length

How well did you know this?

Not at all

Perfectly

What are the spiral valves of heister? What are there purpose?

Mucosal folds- not true valves
Tortuous areas in the cystic duct
Prevents ducts from over distending or collapsing

How well did you know this?

Not at all

Perfectly

Where is the GB located?

Posterior inferior surface of the right lobe of the liver in the GB fossa

How does the GB lay in relation to the main lobar fissure?

Posterior and caudal to the distal end

What parts of the GB are mobile?

Fundus and body

How are the fundus and body positioned with the abdomen?

Varies with pt position

Is the GB a retroperitoneal or intraperitoneal organ?

Intraperitoneal organ

What is the most reliable landmark in identifying the GB?

Main lobar fissure

What are some landmarks for identifying the GB?

RPV Duodenum Right kidney

What is the size and shape of the GB?

Varies widely with pt position Pear or teardrop shape 8-9cm in length 3-5cm in diameter

What are the 3 divisions of the GB? Describe them

Fundus- widest portion, projects below inferior liver margin Body- lies in contact with the visceral surface of the liver Neck- tapered to spiral valves, fixed

What is the most dependent portion of the GB in the LLD position?

Fundus

What is another name for the body of the GB?

Corpus

What is the most dependent portion of the GB in supine?

Neck

What should the GB measure less then in a fasting state?

3mm

What are the 4 layers that make up the GB?

1. Mucosa- inner epithelium 2. Muscular 3. Subserous- connective tissue 4. Serous- outer layer in contact with the peritoneum

What layer of the GB concentrates bile?

Mucosa

What are Rokitansky-Aschoff sinuses? (RA sinuses)

Multiple folds along the inner border of the GB coated with epithelial cells (not normally seen without pathology)

What is the function of the bile ducts?

Drain the liver of bile and carry it into the GI system

What is the function of the GB?

A resivour for bile - stored until required to aid in digestion

How much bile can the GB hold?

40-70ml

How does the GB concentrate the bile?

Secrets mucous and absorbs water

Where would a stone most likely get stuck within the biliary tree?

4th part of the CBD

What sort of pattern should the intrahepatic ducts demonstrate?

Demonstrate a branching pattern

What should the hepatic ducts measure?

No more then 2cm in diameter

Do we normally see the intrahepatic ducts?

Normally no because they are so small but a landmark used is the portal veins

How does knowing the position of the GB aid in the diagnosis of gall stones or sludge?

Moving the patient into different positions should move the stones with them- if not other pathologies present

What controls bile secretion?

Hormones

With the ingestion of fats and amino acids what does the duodenum release into the blood stream?

Cholecystokinin (CCK)

What does the release of CCK stimulate?

GB contraction and the sphincter of Oddi to relax

What does the sphincter of Oddi control?

Passage of bile into the duodenum | Prevents reflux of gastrointestinal fluids into the biliary system

When does the GB contract following a meal?

30min later

What happens to the sphincter of Oddi when the GB is removed?

Looses it tone and the pressure in the CBD lowers to equal intra-abdominal pressure

What happens to the flow of bile if the GB is removed?

Bile flows into duodenum during fasting and non-fasting states Some bile also remains in the ducts

How long after the GB has been removed does the sphincter regain tone?

6 months

What produces bile?

Hepatocytes

What is the function of bile?

Break down fats, helps absorb fatty acids, cholesterol and other lipids from the intestinal tract

How much bile salts are produced per day?

1 gram

What is a precursor to the formation of bile salts?

Cholesterol

What is jaundice?

Yellowish tint due to large quantities of bilirubin

What causes jaundice?

Hemolytic anemia, acute and chronic hepatic disease, obstructive jaundice, inability of bilirubin in conjugate

Where is the arterial blood supply for the GB from?

Cystic artery

How does the venous drainage of the GB work?

Via cystic vein and drains into the portal vein

What is a junctional fold?

A fold that occurs at the junction of the body and infundibulum (neck) May look similar to a separation

What is a Hartman's pouch?

Outpouching in the area of the GB neck

What is a Phrygian cap?

When the GB is partially folded on itself in the region of the fundus

What are some other variants related to the GB?

Septations- thin walls, partial or complete, dividing the GB lumen Excessively mobile Ectopic Low lying the the RLQ Totally or partially embedded in the liver

What is the sonographic appearance of the GB?

Anechoic or nearly anechoic | Well defined walls

What is the pt prep for the GB?

NPO 6-8hours because we want the GB extended to be able to measure the full size and not miss any pathology

What is the scanning technique for the GB?

2.5-5 MHz probe | Supine, decubitus

Why may erect and prone positions be used to examine the GB?

Used to rule out stones lodged in the neck and cystic duct

What do we examine when imaging the GB?

size, shape, content, wall thickeners and area around GB for fluid

Why are windows important in examining the GB?

To minimize reverberation artifact

What are the 3 lab tests used to see if function of GB is distrubted?

1. Bilirubin 2. Alkaline Phosphatase 3. Leukocytes

What does increased levels of bilirubin INDIRECTLY suggest in the GB?

Hemolysis RBC degradation Abnormal hepatocellular uptake

What does increased levels of bilirubin DIRECTLY suggest in the GB?

Extrahepatic obstruction Bile duct disease Intrahepatic disruption

What does increased levels of alkaline phosphatase in the GB suggest?

Extrahepatic biliary obstruction

What do leukocytes measure?

The reaction of body to infection

What do increased levels of leukocytes suggest?

Acute and chronic cholecystitis | Injury to bile ducts

What are other tests to image and evaluate the GB?

1. HIDA scan | 2. ERCP

What is a HIDA scan?

Nuclear medicine test Evaluates function of the GB Radio pharmaceutical injected into patient Passes through the blood into the liver and then the biliary system