17 - Gallbladder and Extrahepatic Biliary Tree 2026

Muscularis mucosa, submucosa

Which histologic layers are notably absent in the gallbladder? (2)

Cystic artery

The hepatocystic triangle is used to locate the cystic artery during laparoscopic cholecystectomy

What structure is found within the hepatocystic triangle (modern preferred term for what was traditionally called Calot's triangle)?

Cystic artery

Calot node

What structure is found within the triangle of Calot?

Cystic duct

Common hepatic duct

Inferior margin of right lobe of liver

The hepatocystic triangle of Budde contains the cystic artery. What are its borders?

500 to 1000 mL/day

Approximately how much bile is formed per day?

Sphincter of Oddi

This structure regulates the flow of bile and pancreatic juice into the duodenum

Ultrasound

What is the initial investigation of choice in the evaluation of gallstones?

Hyperechogenicities with posterior sonic shadowing; moves with changes in position

What is the characteristic ultrasound finding of cholelithiasis?

Black pigment stones

These pigment stones are associated with hemolytic disorder and cirrhosis

Brown pigment stones

These pigment stones are associated with bacterial infection due to bile stasis

Chronic cholecystitis

Symptoms are caused by partial obstruction of the cystic duct

What is the most common presentation of gallstone disease, characterized by recurrent biliary colic?

Hemoglobinopathies such as sickle cell disease

Hereditary spherocytosis and thalassemia at time of splenectomy;

Transplant recipients (cardiac and lung)

In what clinical scenarios is prophylactic cholecystectomy indicated? (3)

No

Based on current recommendations, is prophylactic cholecystectomy indicated in diabetic patients?

Gallstones

The rest is caused by acalculous cholecystitis, which arises in the setting of critically ill patients

The vast majority of acute cholecystitis is caused by :

Boas sign

This sign of acute cholecystitis manifests as hyperesthesia in the RUQ or right infrascapular region

Murphy’s sign of acute cholecystitis

48/F presents to the ER with severe RUQ pain radiating to the right shoulder, occurring several hours after samgyupsal buffet, associated with nausea, vomiting, and fever. On PE you note sudden inspiratory arrest with deep palpation below the right costal margin during deep inspiration. What is this sign called, and what is the likely diagnosis?

Local signs of inflammation (Murphy’s sign, RUQ pain)

Systemic signs of inflammation (fever, high CRP, elev WBC)

Imaging findings

According to TG18, what are the diagnostic criteria for acute cholecystitis? (3)

Ultrasound

Diagnostic test of choice for acute cholecystitis?

Early laparoscopic cholecystectomy (within 72 hours)

Patient presents with mild acute cholecystitis (Grade I) based on TG18. Next step in management?

Emergency gallbladder drainage and management of organ dysfunction

Patient presents with severe acute cholecystitis (Grade III) based on TG18. Next step in management?

Primary choledocholithiasis

This type of choledocholithiasis is formed in the CBD and is associated with biliary stasis and infection

Secondary choledocholithiasis

This type of choledocholithiasis results from migration of gallbladder stones into the CBD

Retained choledocholithiasis

Missed during the operation

___ stones are stones identified by cholangiography shortly after cholecystectomy

Residual choledocholithiasis

Has same composition (black pigment or cholesterol) as the gallbladder stones

___ stones are stones found later, but within 2 years after cholecystectomy.

Recurrent choledocholithiasis

Assumed to be primary common duct stones, usually of the brown pigment type

___ stones are stones found > 2 years after the cholecystectomy

Endoscopic retrograde cholangiopancreatography (ERCP)

This endoscopic procedure is the gold standard for the management of choledocholithiasis. Serves both diagnostic and therapeutic purpose

Magnetic resonance cholangiopancreatography (MRCP)

This imaging procedure is used to evaluate the anatomy of the entire biliary tree and is a non-invasive procedure, requires no IV contrast

Mirizzi syndrome

65/F with known cholelithiasis presents with jaundice, RUQ pain, tea-colored urine, and intermittent fever. UTZ reveals an impacted stone in the gallbladder neck, dilation of the common hepatic duct, and a normal-caliber common bile duct. Diagnosis?

Bouveret syndrome

Uncommon form of gallstone ileus characterized by gastric outlet obstruction caused by gallstone impaction in the pylorus or proximal duodenum after its passage through a cholecystoduodenal fistula

Intraoperative cholangiography (IOC)

History of pancreatitis or jaundice are indications for intra-operative ___ during laparoscopic cholecystectomy

Common hepatic duct

Mirizzi syndrome results in extrinsic compression of the ___ from an impacted stone in the cystic duct or Hartmann's pouch of the gallbladder

Ileocecal valve

Gallstones can cause small bowel obstruction through a cholecystoenteric fistula. They typically impact at the __

Gallstones

What is the most common cause of cholangitis?

Gram-negative aerobes and anaerobes (E. coli, Klebsiella)

What are the most common causative pathogens of cholangitis?

Fever

RUQ pain

Jaundice

What are the components of Charcot's triad of acute cholangitis?

Fever

RUQ pain

Jaundice

Septic shock

Altered mental status

What are the components of Reynold's pentad of acute cholangitis?

Systemic inflammation (fever, chills, labs)

Cholestasis (jaundice, labs)

Imaging (biliary dilatation or evidence of etiology)

According to TG18, what are the diagnostic criteria for acute cholangitis? (3)

Choledochal cysts

What condition refers to congenital cystic dilatations of the biliary tree?

Type 1 (fusiform diverticulum)

Which type of choledochal cyst is the most common type?

Type 2 (saccular diverticulum)

Which type of choledochal cyst involves a saccular diverticulum?

Type 3

Which type of choledochal cyst involves choledochoceles and/or multiple cysts?

Type 4a

Which type of choledochal cyst involves both extrahepatic and intrahepatic ducts?

Type 4b

Which type of choledochal cyst involves the extrahepatic duct only?

Type 5

Which type of choledochal cyst involves the intrahepatic ducts only?

Type 5

Which type of choledochal cyst is also known as Caroli disease?

Choledochal cysts

In anomalous pancreatobiliary duct junction, activated pancreatic enzymes can reflux into the bile duct and cause inflammation, ultimately leading to cystic dilatation. This refers to what condition?

Sclerosing cholangitis

This condition of the biliary tree involves inflammatory strictures that affect both the extra- and intrahepatic biliary tree. On ERCP, presents with multiple dilation and strictures or a "beading pattern"

Primary sclerosing cholangitis (PSC)

This pathology of the biliary tree is also associated with ulcerative colitis, Riedel thyroiditis, and retroperitoneal fibrosis

Size >1 cm

Other factors associated with malignancy include age >50 years, rapid growth, sessile morphology, adenomatous histology, presence of single polyp

Most gallbladder polyps have no malignancy potential. However, polyps that are greater than ___ cm in size have increased risk of malignancy

Gallstones >3 cm

What is the most important risk factor for gallbladder carcinoma?

No

This is a change from older teachings; current evidence shows a much weaker or no association with cancer

Is porcelain gallbladder considered a premalignant lesion?

Lamina propria (stage T1a)

Beginning stage T1b or invasion of muscle layer, extended cholecystectomy with lymphadenectomy is now performed

In the management of gallbladder carcinoma, tumor that invades only the ____ can be managed with simple cholecystectomy

Hepatic duct bifurcation

What part of the biliary tree is most commonly involved in cholangiocarcinoma?

Courvoisier sign

An enlarged gallbladder associated with painless jaundice is commonly seen in periampullary malignancy. This is also known as what sign?