Ultrasonography
•	Sonographic Murphy sign (tenderness elicited by pressing the gallbladder with the ultrasound probe)
•	Thickened gallbladder wall (>4 mm, if the patient does not have chronic liver disease and/or ascites or right heart failure)
•	Enlarged gallbladder (long axis diameter >8 cm, short axis diameter >4 cm)
•	Incarcerated gallstone, debris echo, pericholecystic fluid collection
•	Sonolucent layer in the gallbladder wall, striated intramural lucencies, and Doppler signals
MRI
•	Pericholecystic high signal
•	Enlarged gallbladder
•	Thickened gallbladder wall
CT
•	Thickened gallbladder wall
•	Pericholecystic fluid collection
•	Enlarged gallbladder
•	Linear high-density areas in the pericholecystic fat tissue
Tc-HIDA scan (technetium hepatobiliary iminodiacetic acid scan)
•	Non-visualized gallbladder with normal uptake and excretion of radioactivity
•	Rim sign (augmentation of radioactivity around the gallbladder fossa)