Diagnostic Ultrasound - Abdomen and Pelvis

Chronic Cholecystitis
TERMINOLOGY
Definitions
• Chronic inflammation of gallbladder (GB) causing wall
thickening and fibrosis, following single or recurrent
episodes of cystic duct obstruction
IMAGING
General Features
• Best diagnostic clue
○ Gallbladder wall thickening with gallstones, ±contraction
○ Absence of acute inflammation
Ultrasonographic Findings
• Grayscale ultrasound
○ Diffuse GB wall thickening, echogenic wall
○ Presence of gallstones in nearly all cases
○ Pericholecystic inflammation usually absent
○ Typically contracted but may be distended
– When contracted, contraction persists in fasting state
• Power Doppler
○ No increased flow within thickened gallbladder wall
Nuclear Medicine Findings
• Hepatobiliary scintigraphy
○ Delayed GB visualization (up to 2-4 hours)
○ Visualization of bowel activity prior to GB activity
○ Dysmotility (ejection fraction < 35% after
cholecystokinin)
○ Distinguishes acute from chronic cholecystitis
Imaging Recommendations
• Best imaging tool
○ US is initial imaging tool but is nonspecific
○ Clinical history is critical
• Protocol advice
○ Ensure adequate fasting (> 6 hours) prior to US
examination to avoid false-positive contraction
○ Examine patient in multiple planes/positions to detect
gallstone in severely contracted GB
DIFFERENTIAL DIAGNOSIS
Sympathetic/Reactive GB Wall Thickening
• Known underlying causes (e.g., hypoalbuminemia, cirrhosis,
CHF) usually detected clinically
• Smooth hypoechoic wall thickening ± linear striations
Adenomyomatosis of Gallbladder
• "Comet tail" artifacts
• More commonly affects fundus or mid GB with focal
thickening rather than diffuse involvement
Gallbladder Carcinoma
• Ill-defined infiltrative wall thickening/mass
• Invasion of adjacent liver parenchyma and regional nodal
metastases
○ Most common pathology of gallbladder
○ 95% associated with gallstone disease
○ Intermittent obstruction of cystic duct causes chronic
low-grade inflammatory infiltration of wall, which can
lead to fibrosis and contraction
Microscopic Features
• Often associated with acute cholecystitis
CLINICAL ISSUES
Presentation
• Most common signs/symptoms
○ Mostly asymptomatic
○ Mild RUQ pain/discomfort after meal
○ Recurrent acute cholecystitis or biliary colic
Demographics
• Epidemiology
○ Same as gallstone disease (i.e., female < male, age > 40,
obesity, etc.)
Natural History & Prognosis
• Good prognosis with minimal symptoms
• Complications include acute cholecystitis, gallbladder
carcinoma, and rarely, biliary-enteric fistula
Treatment
• Cholecystectomy in symptomatic cases or complication of
acute cholecystitis
DIAGNOSTIC CHECKLIST
Image Interpretation Pearls
• Gallstones within thick-walled GB
• No pericholecystic fluid
• Lack of hyperemia in thickened gallbladder wall
SELECTED REFERENCES
1. Bennett GL. Cholelithiasis, cholecystitis, choledocholithiasis, and hyperplastic
cholecystoses. In: Gore RM et al. Textbook of Gastrointestinal Radiology. 4th
ed. Philadelphia: Saunders Elsevier, 2015
2. Knab LM et al: Cholecystitis. Surg Clin North Am. 94(2):455-70, 2014
3. Seretis C et al: Metaplastic changes in chronic cholecystitis: implications for
early diagnosis and surgical intervention to prevent the gallbladder
metaplasia-dysplasia-carcinoma sequence. J Clin Med Res. 6(1):26-9, 2014
4. O'Connor OJ et al: Imaging of cholecystitis. AJR Am J Roentgenol.
196(4):W367-74, 2011
5. Wang DQH et al. Gallstone disease. In: Feldman M et al. Sleisenger and
Fordtran's Gastrointestinal and Liver Disease. 9th ed. Philadelphia: Saunders
Elsevier, 2010
6. Smith EA et al: Cross-sectional imaging of acute and chronic gallbladder
inflammatory disease. AJR Am J Roentgenol. 192(1):188-96, 2009
7. Catalano OA et al: MR imaging of the gallbladder: a pictorial essay.
Radiographics. 28(1):135-55; quiz 324, 2008
8. van Breda Vriesman AC et al: Diffuse gallbladder wall thickening: differential
diagnosis. AJR Am J Roentgenol. 188(2):495-501, 2007
9. Schiller VL et al: Color doppler imaging of the gallbladder wall in acute
cholecystitis: sonographic-pathologic correlation. Abdom Imaging.
21(3):233-7, 1996
10. Lack EE. Cholecystitis, cholelithiasis, and unusual infections of the
gallbladder. In: Lack EE. Pathology of the Pancreas, Gallbladder, Extrahepatic
Biliary tract, and Ampullary Region. New York: Oxford University Press, 2003
Diagnoses: Biliary System
PATHOLOGY
General Features
• Etiology
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