1. Gallbladder and Biliary Tract Disease

2. Cholelithiasis

3. Cholelithiasis
Cholelithiasis is the pathologic state of stones or calculi within the gallbladder lumen.
A common digestive disorder worldwide:
20 million Americans have gallstones
700,000 cholecystectomys performed annually in the U.S.
Most common gastrointestinal disorder requiring hospitalization

4. Cholelithiasis
Most gallstones are composed primarily of bile (80%); remainder are composed of a mixture of bile components
Each type of stone has a particular pathophysiology and specific set of risk factors that alter the equilibrium and solubility of the components of bile.
Pigment stones
Cholesterol stones

5. Cholelithiasis Manifestations of cholelithiasis:
Asymptomatic gallstone patients develop complications at an annual rate of 1-2%.
In symptomatic patients, the complication rate increases to 3%.
Manifestations of cholelithiasis:
Many persons are asymptomatic
Early symptoms are epigastic fullness after meals or mild distress
Biliary colic (if stone is blocking cystic or common bile duct): steady pain in epigastric or RUQ of abdomen lasting up to 5 hours with nausea and vomiting
Jaundice may occur if there is obstruction of common bile duct

6. Ultrasonic Criteria for Cholelithiasis
Sonography is the procedure of choice for identifying gallstones.
Current high-resolution, real-time ultrasound (US) can identify gallstones as small as 2 mm, with a sensitivity greater than 95%.
The technique is rapid, noninvasive, can be performed at the bedside, and does not involve ionizing radiation.
Ultrasonic Criteria for Cholelithiasis
Intraluminal brightly echogenic structure
Stones > 3mm will produce an acoustic shadow
Stones will usually seek gravitational dependency

7. Cholelithiasis Ultrasound
Ultrasound image obtained with a 3,5-MHz transducer demonstrates the multiple stones in the gallbladder with typical acoustic shadows.

8. Cholelithiasis Ultrasound
Ultrasound image obtained with a 3,5-MHz transducer demonstrates a stone in the gallbladder with typical acoustic shadow.
NORMAL GALLBLADER

9. Cholelithiasis Ultrasound
Ultrasound image demonstrates multiple shadowing stones.

10. Cholelithiasis Image Patterns: Stones with shadowing
Ultrasound
Image Patterns:
Stones with shadowing
Stones without shadowing
Gravel
GB filled with stones
Floating stones as fluid level in bile
Adherent Gallstones
Dilation of common bile duct

11. Cholelithiasis Ultrasound
Ultrasound image obtained with a 3-MHz transducer demonstrates pyramidal nonshadowing stones.

12. Cholelithiasis Ultrasound
Wall-echo shadow sign indicates a stone-filled gallbladder.

13. Cholelithiasis
Ultrasound
Layer of gravel with shadowing

14. Cholelithiasis Limitations of Techniques:
US: False negatives may occur with small stones in the presence of biliary sludge. The technique is operator-dependent. Inadequate visualization of the gallbladder may occur in obese or contracted patients, or in patients with abdominal wounds.
Radiographs: Only 15-20% of stones are visible on plain radiographs.
CT: Only 74-79% of gallstones are identified in patients with CT. CT is not a screening tool for uncomplicated cholelithiasis.
MRI: MRI is not a screening tool. Stones may be incidental findings on abdominal MRI.

15. Cholelithiasis
Only 15-20% of stones are visible on plain abdominal film.

16. Noncontrast CT demonstrates a typical, laminated, calcified gallstone.
Cholelithiasis
CT Findings
CT demonstrates a layer of calcific-dense material in the gallbladder that may be gravel or milk of calcium bile
Noncontrast CT demonstrates a typical, laminated, calcified gallstone.

17. ERCP findings in cholelithiasis
Gallbladder and CBD stones

18. Acute cholecystitis Manifestations of acute cholecystitis
Episode of biliary colic involving RUQ pain radiating to back, right scapula, or shoulder; the pain may be aggravated by movement, or deep breathing and may last 12 – 18 hours
Anorexia, nausea, and vomiting
Fever with chills

19. Sonographic features of AC include the following:
Acute cholecystitis
Sonographic features of AC include the following:
Calculi in the GB in more than 90% of patients.
Anterior GB-wall thickness of more than 3 mm
Positive Murphy sign (pain on compression of the GB with the ultrasound probe)
Pericholecystic fluid in severe cases (sign of actual or impending perforation)
Acalculous cholecystitis: Five percent of cases are not associated with gallstones.
Increased transverse GB diameter >4-5 cm
GB distension: About 93% of patients with a GB volume of greater than 70 mL have AC.
Loss of definition of GB margins

20. Acute cholecystitis Ultrasound Ultrasound image demonstrates:
thickening of the gallbladder wall.

21. Acute cholecystitis Ultrasound Ultrasound image demonstrates:
a calculus at the neck of the gallbladder with acoustic shadowing and thickening of the gallbladder wall.
Gallbladder is slightly enlarged

22. Acute cholecystitis Ultrasound Ultrasound image demonstrates:
thickening of the gallbladder wall and loss of definition of GB margins.

23. Acute cholecystitis CT Findings Acute nongangrenous cholecystitis.
CT scan shows pericholecystic fluid
From: CT Findings in Acute Gangrenous Cholecystitis G. L. Bennett et al. AJR 2002; 178:

24. Complications are more common in patients with small, multiple stones.
Acute cholecystitis
Complications of cholecystitis
Chronic cholecystitis occurs after repeated attacks of acute cholecystitis; often asymptomatic
Empyema: collection of infected fluid within gallbladder
Gangrenous cholecystitis with perforation leading to peritonitis or abscess formation
Pancreatitis, liver damage, intestinal obstruction
Complications are more common in patients with small, multiple stones.

25. Acute cholecystitis Ultrasound
Transverse and longitudinal scans demonstrate a complex echo pattern in the area of the gallbladder and pericholecystic fluid - acute gangrenous cholecystitis.

26. Acute cholecystitis CT Findings Acute gangrenous cholecystitis.
CT scan with IV contrast material shows intraluminal linear densities corresponding to intraluminal membranes.
Note lack of contrast enhancement of gallbladder wall and pericholecystic inflammation.
renal cyst
From: CT Findings in Acute Gangrenous Cholecystitis G. L. Bennett et al. AJR 2002; 178:

27. Acute cholecystitis Ultrasound Acute gangrenous cholecystitis.
Sonography demonstrates an anechoic fluid mass situated in the wall of the gallbladder.
Sonograms shows marked laminated sonolucent thickening of the gallbladder wall, with the lumen of the gallbladder full of sludge.
Gallbladder is enlarged

28. Acute cholecystitis CT Findings
Acute gangrenous cholecystitis. CT scan with IV contrast material shows air in gallbladder lumen.
From: CT Findings in Acute Gangrenous Cholecystitis G. L. Bennett et al. AJR 2002; 178:

29. Acute cholecystitis Abscess CT Findings
Acute gangrenous cholecystitis.
CT scan shows loculated fluid attenuation abnormality adjacent to gallbladder, consistent with abscess (a). Defect in gallbladder wall is shown (perforation). White arrow shows pericholecystic inflammation (leading to peritonitis).
From: CT Findings in Acute Gangrenous Cholecystitis G. L. Bennett et al. AJR 2002; 178:

30. Gallbladder Sludge
The term biliary sludge refers to a characteristic ultrasound picture of movable, low-amplitude echoes that layer in the most dependent part of the gallbladder and are not associated with acoustic shadowing.
Sludge is composed of cholesterol crystals, calcium bilirubinate granules, and mucin glycoprotein suspended in bile and forms in an environment that combines a high mucus concentration, dysmotility, and stasis.
The cholesterol and calcium bilirubinate crystals in biliary sludge can lead to gallstone formation.

31. Gallbladder Sludge Ultrasound
Longitudinal scan through the gallbladder shows layering of sludge in the gallbladder lumen.
Sludge can appear, disappear, and reappear, its formation is a dynamic, reversible process

32. Gallbladder Sludge Ultrasound Clinical association with:
hyperalimentation,
hemolysis,
fasting,
pregnancy,
post-op state,
cirrhosis
Differentiate from:
hematobilia,
biliary tract tumors,
purulent bile
This longitudinal view of the gallbladder, as imaged from the gastric antrum, reveals dependent echogenic sludge.

33. Gallbladder polyps
It is estimated that as many as 4% of gallbladders examined by ultrasound will have evidence of polyp formation.
The 95% of all gallbladder polyps do not give rise to cancer. They consist of cholesterol, muscle tissue or inflammatory tissue.
The minority are adenomatous polyps, which can progress to cancer.
It is believed that the risk of cancer in an adenomatous gallbladder polyp is related to its size, with those larger than 1 cm being at high risk.

34. Gallbladder polyps Chronic cholecystitis with gallbladder polyps
Findings: Ultrasound scans demonstrate a small gallbladder with diffusely thickened wall and adjacent fixed small soft tissue polyps. There was no biliary ductal dilatation or shadowing echogenic stones within the gallbladder.

35. Porcelain Gallbladder
Extensive calcium encrustation of the gallbladder wall variably has been termed calcified gallbladder, calcifying cholecystitis, or cholecystopathia chronica calcarea.
Most porcelain gallbladders (90%) are associated with gallstones.
The term porcelain gallbladder has been used to emphasize the blue discoloration and brittle consistency of the gallbladder wall at surgery.

36. Porcelain Gallbladder
Patients are usually asymptomatic, and porcelain gallbladder is found incidentally on plain abdominal radiographs, sonograms, or CT images.

37. Porcelain Gallbladder
Porcelain gallbladder is uncommon, and recognizing the clinical and imaging characteristics of the disease is important because of the high frequency (22%) of adenocarcinoma in porcelain gallbladder
Image from an upper gastrointestinal series demonstrates a porcelain gallbladder