RADIOLOGY: HEPATOBILIARY: Case# 33652: ACUTE CHOLECYSTITIS. 47 year old female with right upper quadrant pain and fever. Axial and sagittal transabdominal images of the RUQ reveal marked thickening of the gallbladder wall with multiple shadowing stones seen within the gallbladder. Acute cholecystitis occurs in approximately one-third of patients with gallstones. In western countries, cholesterol stones predominate and is almost three times as high in women as it is in men. The incidence of acute cholecystitis increases with age and multiparity. Ultrasound reveals stones in approximately 95% of patients with acute cholecystitis. A sonographic Murphys sign is demonstrated in 90% pa patients. Secondary sonographic criteria are less specific but include wall thickening of greater than 3 mm and ductal dilatation. Complications of acute cholecystitis include emphysematous and gangrenous cholecystitis as well as perforation.