Background: Persistent small common bile duct (CBD) stones after endoscopic sphincterotomy (EST) and stone extraction may be a nidus for stone growth and could be detected by intraductal US (IDUS). CBD saline solution irrigation may flush out residual stones.
Objectives: Our purpose was to determine the frequency of residual CBD stones after EST and basket/balloon extraction by using IDUS and to assess the effectiveness of saline solution irrigation in clearing remnant CBD stones.
Design: Prospective study.
Setting: General Hospital Singapore.
Patients: Seventy patients (mean age 62 years, 51% male) were recruited.
Interventions: In the presence of CBD stones, EST and stone extraction were performed, followed by IDUS. If residual stones were detected, a catheter was inserted into the proximal CBD, saline solution irrigation performed, and IDUS repeated.
Main outcome measurements: (1) The frequency of residual stones detected by IDUS after EST and basket/balloon extraction and (2) the effect of saline solution irrigation in clearing residual CBD stones.
Results: Cholangiogram showed CBD stones in 38 of 70 patients (median 1 [range 1-5], mean size 7.6 mm [range 3.0-12.0 mm]). IDUS showed CBD stones in 32 of 32 with normal cholangiogram (median 2 [range 1-8], mean size 2.6 mm [range 0.9-7.2 mm]). After EST and stone extraction, IDUS showed persistent stones in 28 of 70 (median: 2 [range 1-5], mean size 2.2 mm [range 1.1-4.6 mm]). The CBD was irrigated with a mean of 48 mL of saline solution. Repeat IDUS showed persistent CBD stones in 2 of 70, and these were flushed out by further saline solution irrigation.
Limitations: Single-center study.
Conclusion: IDUS detected small residual CBD stones that persisted after EST and basket/balloon extraction. Saline solution irrigation appeared useful in clearing residual small stones.