The authors concluded that cholescintigraphy demonstrated the best sensitivity of 97% (95% confidence interval [CI], 96%-98%) and specificity of 90% (95% CI, 86%-95%) in detecting AC, whereas US had a sensitivity of 88% (95% CI, 74%-100%) and a specificity of 80% (95% CI, 62%-98%). Other studies performed since then have shown similar findings. Although cholescintigraphy is recognized to have a higher sensitivity and specificity, US remains the initial imaging test of choice for imaging patients with suspected AC for a variety of reasons, including shorter study time, morphologic evaluation, confirmation of the presence or absence of gallstones, evaluation of intrahepatic and extrahepatic bile ducts, gallbladder wall edema, pericholecystic fluid, and identification or exclusion of alternative diagnoses [15-17,40]. However, the usefulness of US is limited in critically ill patients where gallbladder abnormalities are common in the absence of AC [22,43]. If complicated cholecystitis (emphysematous, hemorrhagic, gangrenous, or perforated, among others) is suspected, US remains the first choice of investigation for biliary symptoms or right upper quadrant abdominal pain. It is important to note, however, that some patients with complicated cholecystitis may present just like those with noncomplicated disease [7]. Depending on the complication, one may detect intraluminal hyperechoic blood products, intraluminal gas or gas in the gallbladder wall, intraluminal debris or membranes, or discontinuity of the gallbladder wall [7,30,44]. The gallbladder may appear contracted or distended, and pericholecystic fluid is variably present. Although its sensitivity to some complications of cholecystitis is often limited, a normal appearance of the gallbladder, especially the wall, makes acute gallbladder pathology very unlikely. Thus, US remains the first imaging choice if complications of cholecystitis are suspected. Variant 3: Right upper quadrant pain.
Right Upper Quadrant Pain. The authors concluded that cholescintigraphy demonstrated the best sensitivity of 97% (95% confidence interval [CI], 96%-98%) and specificity of 90% (95% CI, 86%-95%) in detecting AC, whereas US had a sensitivity of 88% (95% CI, 74%-100%) and a specificity of 80% (95% CI, 62%-98%). Other studies performed since then have shown similar findings. Although cholescintigraphy is recognized to have a higher sensitivity and specificity, US remains the initial imaging test of choice for imaging patients with suspected AC for a variety of reasons, including shorter study time, morphologic evaluation, confirmation of the presence or absence of gallstones, evaluation of intrahepatic and extrahepatic bile ducts, gallbladder wall edema, pericholecystic fluid, and identification or exclusion of alternative diagnoses [15-17,40]. However, the usefulness of US is limited in critically ill patients where gallbladder abnormalities are common in the absence of AC [22,43]. If complicated cholecystitis (emphysematous, hemorrhagic, gangrenous, or perforated, among others) is suspected, US remains the first choice of investigation for biliary symptoms or right upper quadrant abdominal pain. It is important to note, however, that some patients with complicated cholecystitis may present just like those with noncomplicated disease [7]. Depending on the complication, one may detect intraluminal hyperechoic blood products, intraluminal gas or gas in the gallbladder wall, intraluminal debris or membranes, or discontinuity of the gallbladder wall [7,30,44]. The gallbladder may appear contracted or distended, and pericholecystic fluid is variably present. Although its sensitivity to some complications of cholecystitis is often limited, a normal appearance of the gallbladder, especially the wall, makes acute gallbladder pathology very unlikely. Thus, US remains the first imaging choice if complications of cholecystitis are suspected. Variant 3: Right upper quadrant pain.