Efficacy and safety of direct transnasal cholangioscopy with standard ultraslim endoscopes: results of a large cohort study.Meves V, Ell C, Pohl J. Gastrointest Endosc. 2013 Jul 9. [Epub ahead of print] BACKGROUND: Direct cholangioscopy (DC) with ultraslim endoscopes and free-hand cannulation of the common bile duct (CBD) is a promising technique for evaluating and treating cholangiopathy. However, its safety and success rates are as yet unclear. OBJECTIVE: To evaluate the overall success rates and adverse events with the procedure. DESIGN: Single-center, prospective cohort study; 12 patients retrospectively enrolled. SETTING: Academic tertiary referral center. PATIENTS: A total of 100 DC procedures in 84 patients with biliary disease were evaluated prospectively. INTERVENTIONS: DC performed with the patient under conscious sedation. MAIN OUTCOME MEASUREMENTS: Overall success rates and adverse events with the procedure. RESULTS: In 34 cases with small- or medium-sized sphincterotomies, sphincteroplasty was performed with a 10-mm dilating balloon before DC. The intraductal area of interest was successfully accessed in 87% of the procedures. The intended interventions were successfully carried out in 81 patients (93.1%), but failed in 6 (6.9%). In patients without significant strictures, intrahepatic exploration of the bile ducts beyond the level of the bifurcation was feasible in only 10.8%. The mean total procedure time was 38.6 ± 12.2 minutes. Adverse events occurred in 12 procedures (12%) and were managed conservatively. LIMITATIONS: All procedures were performed by 1 endoscopist. CONCLUSION: DC is safe and allows direct, high-resolution examination and a wide range of therapeutic options in the bile ducts in the majority of patients with biliary disease. However, the range of access is limited to the main bile duct. Suspected pathology restricted to the proximal intrahepatic ducts beyond the bifurcation is therefore not a good indication for DC.