Prospective randomized comparison of short-access mother-baby cholangioscopy versus direct cholangioscopy with ultraslim gastroscopes

Background: Mother-baby technologies, the criterion standard for cholangioscopy, have several limitations. A novel, short-access, mother-baby (SAMBA) system may improve this technique. Direct cholangioscopy (DC) was recently developed as an alternative to mother-baby cholangioscopy.

Objective: Comparison of success rates with SAMBA and DC.

Design: Single-center, randomized, controlled trial.

Setting: Academic tertiary-care referral center.

Patients: Sixty patients with suspected cholangiopathies randomized to either SAMBA (n = 30) or DC (n = 30).

Intervention: Cholangioscopy under deep sedation.

Main outcome measurements: Technical success rate of diagnostic or therapeutic procedure.

Results: A total of 24 and 21 diagnostic procedures were performed in the SAMBA and DC groups, respectively. There were no significant differences in the overall technical success rates between SAMBA (90.0%) and DC (86.7%) (P = 1.0). There was better correlation between the endoscopic prediction and histologic findings in DC (P = .013). Procedure times were shorter in DC (P < .03). In patients without significant stenoses, SAMBA allowed intrahepatic bile duct exploration in all cases, compared with 10.5% of cases in DC (P < .01). No differences regarding adverse event rates between the groups occurred (10.0% both groups).

Limitations: Small sample size. Heterogeneous indications for cholangioscopy. DC requires advanced skills of the endoscopist. The study is not replicable.

Conclusion: SAMBA and DC offer high technical success rates for diagnostic and therapeutic interventions. The advantages of DC consist of superior imaging, shorter total procedure time, and a wider working channel for adequate tissue sampling. SAMBA is better than DC with regard to intraductal stability and accessibility of the intrahepatic bile ducts.