Gallbladder and Biliary

Question 1

Facts

Answer 1

• Intraperitoneal
• GB stores and concentrates bile
• Ducts transport it
• Cholecystokinin (from duodenum) makes the GB contract releasing the bile into system

Question 2

Anatomy

Answer 2

• Flow of bile in the biliary tree
• Intrahepatic biliary radicles (part of portal triads) drain into right and left hepatic ducts.
• RHD and LHD into CHD. CHD connects to cystic duct as it becomes extrahepatic.
• Cystic duct contains spiral valves of Heister which allow bile to flow into GB but not leak out until GB is contracted (with cholecystokinin).
• From cystic duct, then connects to CBD. CBD joins the main pancreatic duct at the ampulla of Vater. Sphincter of Oddi controls the flow of enzymes into the duodenum.

Question 3

Gallbladder

Answer 3

• Neck, body, and fundus: Fundus is the most dependent. Cystic duct connects neck of GB to rest of biliary tree. Vascular supply: Cystic artery (branch of right hepatic artery)
• Wall layers inner to outer: Mucosa > Fibromuscular > Serosa

Question 4

Variants

Answer 4

• Phrygian cap: Most common. Fold of fundus over body
• Hartmann pouch: Outpouching of neck
• Junctional fold: Fold at neck

Question 5

Sonography

Answer 5

• NPO min 6 hours, otherwise GB wall will be contracted and appear thickened
• Normal GB wall thickness up to 3mm (Sagittal with calipers perpendicular to wall)
• GB width in transverse plane up to 4cm
• CBD up to 6mm at porta hepatis (Up to 10mm if hx cholecystectomy). In older patients, add 1 mm per decade of life (80yo = up to 8mm)
• Cystic duct may also be seen posterior to the CBD.

Question 6

Intro to Pathology

Answer 6

• Irritating = stones Clinical: pain, nothing else unless progressed to obstruction or infection
• Blocking = obstructive disease”blocking flow”. When dilated ducts or GB observed, evaluate distal to locate obstruction. Stones or tumors Clinical: Abnormal labs / jaundice / pain LABS: ALP and conjugated bilirubin
• Infection = acute -itis. Most commonly caused by obstruction. Clinical will be obstruction + infection symptoms Clinical: pain, labs, and infection symptoms like fever

Question 7

Polyps

Answer 7

Projection of tissue from GB wall. Cholesterol polyps are most common and usually <10mm. Related to umbrella condition called cholesterolosis or hyperplastic cholecystosis. Strawberry GB, diffuse wall polyps. Sono: Echogenic non-mobile mass projecting from inner lumen

Question 8

Adenomyomatosis

Answer 8

Muscular layer forms little pockets called Rokitansky-Aschoff sinuses. Cholesterol crystals get stuck inside Sono: Focal or diffuse wall thickening with comet tail artifact

Question 9

Porcelain GB

Answer 9

Calcification of the GB wall. May have increased risk of developing stones Sono: Hyperechoic GB with shadowing. Shadowing is mild and the posterior wall is still seen.

Question 10

Gallbladder sludge Aka viscid bile

Answer 10

• Caused by biliary stasis or in other words, bile is not flowing. May be seen with obstructive disease or in patient conditions where patient is not eating normally such as ICU patient (total parental nutrition, IV hyperalimentation)
• Sono: Low-level dependent echoes. Fluid level line.
• Tumefactive sludge: thicker sludge forming sludge balls, will be mobile (need to move pt)
• Hepatization of GB: full of tumefactive sludge. Isoechoic to liver texture

Question 11

Cholelithiasis

Answer 11

• Biliary stones or gallstones in gallbladder.
• 6 F’s: fat, female, fertile, flatulent, fair, forty.
• Most common location is the GB fundus due to dependency
• Clinical: May be asymptomatic if small or non-obstructing. Common symptoms include RUQ pain, biliary colic, nausea and vomiting, radiating pain to shoulders
• Sono: Hyperechoic with posterior shadowing.
• WES = wall echo shadow. A GB packed with stones. Only the anterior wall, echo, solid shadow posterior. GB is not seen and posterior wall is not visualized.
• When documenting stones, must prove mobility by placing patient in at least one additional position Minimum of 2 positions (example: supine and the LLD)

Question 12

Choledocholithiasis

Answer 12

• Gallstones in bile ducts. Most likely to be obstructive and symptomatic (Obstructive labs: ALP and bilirubin).
• Most common cause of biliary obstruction, obstructive jaundice, and most likely in distal CBD, near ampulla. Extrahepatic ducts most likely to dilate first.
• Mirizzi syndrome: jaundice, pain, fever with stone lodged in cystic duct and compression of CBD (NOT COMMON)

Question 13

Gallbladder enlargement

Answer 13

• Hydropic GB >4cm indicates obstruction of distal biliary tree = cystic duct, CBD. Although intrahepatic ducts may be dilated, they would be a side effect and not the cause. The cause of biliary dilatation will always be see DISTAL to the dilatation. Further evaluation of CBD and pancreatic head is important to identify cause.
• Courvoisier GB: Enlarged GB caused by pancreatic head mass. Painless jaundice

Question 14

Acute Cholecystitis

Answer 14

Most common cause: obstructive gallstone in cystic duct or neck.
- Clinical: + Murphy’s sign (pain with probe pressure), fever, leuko, elevated ALP, bilirubin, nausea, vomiting
- Sono: Thickened GB wall, pericholecystic fluid, stones, sludge

Question 15

Gangrenous cholecystitis/Perforation

Answer 15

Wall starts eroding. Bulging of wall, craters, and sloughed membranes. High risk for perforation. ** Dangerous = perforation may lead to peritonitis = death

Question 16

Empyema (suppurative cholecystitis)

Answer 16

Pus filling and distending GB.

Question 17

Emphysematous cholecystitis

Answer 17

Emphysema = air. Air or gas bubbles produced by bacteria in the wall. Increased risk: Diabetics and immunocompromised Sono: Reverberation (comet-tail or ring down) “champagne sign”

Question 18

Acalculus Cholecystitis

Answer 18

• “No stone”.
• Most likely seen in children, hospitalized or immunocompromised pt.
• Clinical: RUQ pain, fever, leuko. Similar to acute cholecystitis with exception of NO obstructive labs.
• Sono: Thickened wall, pericholecystic fluid. No sludge or stone

Question 19

Acute cholangitis

Answer 19

• Most commonly caused by obstructed stone.
• Clinical: Charcot triad (pain, fever, jaundice), elevated ALP, bilirubin, nausea, vomiting
• Sono: Thickened bile duct walls >5mm, stones, sludge
• The acute disease of the bile ducts caused by an ascending bacterial infection from the small intestines and characterized by neutrophilic inflammation

Question 20

Sclerosing cholangitis

Answer 20

• Sclerosis = hardening and thickening.
• Chronic type of fibrotic thickening of bile ducts. Increases risk for cholangiocarcinoma

Question 21

Pneumobilia

Answer 21

• “Pneuma” = air.
• Air or gas formation within biliary tree. Caused by recent surgery or infection.
• Sono: Comet-tail or ring down (reverb) artifacts scattered through liver

Question 22

Ascariasis

Answer 22

Parasites in bile ducts. Movement of worm in realtime confirms presence of ascaris

Question 23

Gallbladder carcinoma

Answer 23

• Most common cancer of the biliary tract.
• Suspected when polyp >1cm. Clinical: Weight loss, RUQ pain, jaundice if obstructive
• Sono: Non-mobile mass along wall >1cm

Question 24

Cholangiocarcinoma

Answer 24

• Cancer within the bile ducts.
• Most common type is Klatskin tumor, located at the junction of the right and left hepatic ducts (hepatic duct bifurcation).
• Ductal dilatation above the cancer.
• Clinical: Weight loss, RUQ pain, jaundice, pruritus (excessive itchiness), Hx of sclerosing cholangitis
• Sono: Dilated intrahepatic ducts that abruptly terminate

Question 25

Pancreatic carcinoma

Answer 25

Although not a biliary disease, most common location of the mass is in the pancreatic head, therefore causing biliary obstruction. Clinical and sono will be similar to biliary obstruction: jaundice (direct bilirubin), elevated ALP and dilated ducts: CBD and proximal.