Does Endoscopic Ultrasonography Influence the Management of Clinically Suspected Cholecystitis?

Abstract

Purpose: Endoscopic ultrasonography (EUS) is useful in detecting common bile duct stones (CBDS), especially in cases with stones smaller than 10 mm and without dilatation of the common bile duct. This study is designed to evaluate the usefulness of EUS in determining the management of clinically suspected cholecystitis. Methods: In this study, we retrospectively analyzed 198 available cases, which were diagnosed as cholecystitis from symptoms and/or laboratory data at our hospital between April 2000 and September 2004. All cases underwent operations, and were histopathologically confirmed. As CBDS and occult biliary tract carcinoma (BTC) are thought as determinant factors for the management of cholecystitis, we evaluate the diagnostic accuracy of detecting these diseases in the following diagnostic process. First, we diagnosed these factors only using computed tomography (CT) and/or conventional ultrasonography (US) in all cases. If CBDS were detected, we performed endoscopic treatment before the operation without performing EUS. Second, we performed EUS additionally for further examination, and reconsidered the management according to EUS findings. All cases were classified into 3 groups: cholecystitis without CBDS, with CBDS, with BTC. Results: The number of each group was as follows: cholecystitis without CBDS, 109; with CBDS, 83; with BTC, 7 (gallbladder carcinoma 4 and extrahepatic bile duct carcinoma 3). Only using CT and/or US, 27 of 83 cases with CBDS were misdiagnosed as cholecystitis without CBDS and 6 cases with BTC were missed. So 33 cases were incorrectly diagnosed in total, and the over all accuracy was 83.3% (165/198). EUS was performed in 142 cases, and 26 cases with CBDS and 5 cases with BTC were correctly diagnosed in addition. So, additional EUS influenced 31 of 33 misdiagnosed cases correctly. But even after performing EUS, 1 case with CBDS and 1 case with BTC were still missed. Besides, 1 case without CBDS was incorrectly diagnosed as a case with BTC. The over all accuracy was 97.9% (139/142), and was statistically higher than that using only CT and/or US (p<0.0005). Conclusions: EUS is very useful in detecting not only CBDS but also other diseases including occult biliary tract carcinoma. We recommend preoperative EUS for all cases, which are diagnosed as cholecystitis without CBDS by CT and/or US.