US diagnosis of choledocholithiasis: a reappraisal.

Sonographic detectability of choledocholithiasis using real-time sector scanners appears to be improved in comparison with series previously reported. To establish this premise, 78 consecutive patients with choledocholithiasis were evaluated prospectively by ultrasound (US) prior to surgery or endoscopic retrograde cholangiopancreatography. Preoperative US analysis yielded a 55% sensitivity for detection of choledocholithiasis (43 patients), representing more than a threefold increase over previous series. Dilated extrahepatic ducts were seen in 52 patients (67%), 40 of whom (77%) were seen to have an intraluminal stone. Extrahepatic ducts were normal in size in 26 patients (33%), only three of whom were seen to have a stone. This marked improvement in detection rate probably is related to improvements in imaging technology as well as to increased diagnostic efforts based on cognizance of the difficulty in making the diagnosis of choledocholithiasis sonographically.