Background and aim: The aim of the present study was to determine whether additional intraductal ultrasound (IDUS) to confirm complete stone clearance decreases the recurrence rate of common bile duct stones for a 3-year period after endoscopic papillotomy (EPT).
Methods: IDUS was carried out with a thin-caliber ultrasonic probe (diameter 2.0 mm, frequency 20 MHz) via transpapillary route after stone extraction. If IDUS showed evidence of residual stones and/or sludge, endoscopic management was performed until IDUS examination was negative. A prospective study was conducted on 59 consecutive patients undergoing additional IDUS after stone extraction between January 1996 and May 2003 (IDUS group). The recurrence rate of common bile duct stones was compared with a historical control group (August 1988 to December 1995) consisting of cases that did not undergo IDUS (non-IDUS group). Potential risk factors for recurrence of common bile duct stones were assessed by univariate and multivariate analysis on logistic regression.
Results: In 14 of 59 patients (23.7%), IDUS detected small residual stones not seen on cholangiography. The recurrence rate was 13.2% (17 of 129 patients) in the non-IDUS group and 3.4% (two of 59 patients) in the IDUS group (P < 0.05). Multivariate analysis subsequently identified non-IDUS status as an independent risk factor for recurrence (odds ratio 5.12, 95% CI 1.11-23.52, P = 0.036).
Conclusions: Additional IDUS to confirm complete stone clearance after EPT decreases the early recurrence rate of common bile duct stones.