Diagnosis of choledocholithiasis by endoscopic ultrasonography

Endoscopic ultrasonography is a promising procedure for the diagnosis of extrahepatic cholestasis. Accuracy for the diagnosis of choledocholithiasis by ultrasonography and computed tomography were prospectively compared with endoscopic ultrasonography in 62 consecutive patients.

Final diagnosis was determined by endoscopic retrograde cholangiography with or without sphincterotomy or intraoperative cholangiography with or without choledochoscopy. All of the patients had abdominal ultrasonography, computed tomography, endoscopic ultrasonography, and either an endoscopic retrograde (n = 40) or intraoperative cholangiography (n = 32) performed.

Choledocholithiasis was confirmed in 22 patients. Thirteen patients had a stone with a diameter < 1 cm, and 14 had a nonenlarged common bile duct. Endoscopic ultrasonography was more sensitive (97%) than ultrasonography (25%; P < 0.0001) and computed tomography (75%; P < 0.02). Specificity and positive predictive value were not significantly different. Negative predictive value of endoscopic ultrasonography (97%) was better than that of ultrasonography (56%; P < 0.0001) and computed tomography (78%; P < 0.02). Results were unchanged after six patients in whom the absence of choledocholithiasis was considered probable after follow-up were excluded. Endoscopic ultrasonography results did not depend on stone diameter or common bile duct dilatation.

Endoscopic ultrasonography appears to be the best diagnostic tool for the diagnosis of choledocholithiasis compared with other noninvasive procedures.