Bile duct stone size may influence the efficacy of endoscopic sphincterotomy with or without large-balloon dilation - A meta-analysis

Background: Endoscopic sphincterotomy (EPT) and/or large balloon dilation (EPBD) are used to remove common bile duct (CBD) stones. This meta-analysis compared the efficacy of EPT + EPBD versus EPT alone in removal stones based on stone size. Methods Twenty-one studies (10 randomized control trials (RCTs) and 11 non-RCTs) were identified and reviewed from searches of Embase, PubMed, and Web of Science. CBD stone’s size was measured with reference to the diameter of the duodenoscope (13mm) and the size of the large dilatation balloon (17mm) from cholangiogram. The stone clearance rate was compared according to the mean stone size and further divided into group A (small)  17 mm. The study protocol was registered with Prospero (number CRD42020171689). Results In RCTs, EPT + EPBD had a significantly better stone clearance rate (OR = 1.95, 95% CI: 1.15 ~ 3.30) and required less mechanical lithotripsy (ML) (OR = 0.39, 95% CI: 0.23 ~ 0.65) than EPT for removing CBD stones. These results were also supported by analysis of non-RCTs. In subgroup analysis, EPT + EPBD had a significantly better initial stone clearance rate than EPT in groups B and C, but not A. EPT + EPBD also required significantly less ML than EPT in groups B and C. In meta-regression analysis, group B has a better correlation of log OR with the size of CBD stone in initial stone clearance and less ML usage rates but not for group C with larger stones. Conclusions EPT + EPBD had a significantly better initial stone clearance rate and required less ML than EPT for medium CBD stones but the efficacy was limited for the large CBD stones. Trial registration: The protocol for this review was registered in PROSPERO (registration number CRD42020171689).