Introduction

Biliary cannulation is a key parameter in any training program and is pivotal in post-ERCP pancreatitis (PEP). The development of a simple and reliable model to predict a difficult cannulation ex-ante would allow us to develop better training programs and potentially decrease PEP, by matching difficult cases with more experienced endoscopists. However, there is no model published that allows to predict a difficult biliary cannulation (DBC).

Aims & Methods

We aimed to develop of a model to predict a DBC - defined as (i) taking longer than 5 minutes, (ii) with at least 5 attempts for BC or (iii) with at least one pancreatic duct cannulation -, but before biliary cannulation.
A prospective cohort study was carried out in a large volume center for ERCP between January 2021 and March 2022. All patients with naïve papilla for biliary ERCP were enrolled (n=278). Two explained variables were evaluated (i) time to achieve biliary cannulation and (ii) DBC. Several predictors were evaluated including Viana’s classification of the papilla and a new 5 dimensions framework for assessing the maneuverability of the scope by the endoscopist in the duodenum. A linear regression model and a qualitative response probit model were developed.

Results

Among the 278 patients, 196 (43.4%) were male, with a mean age of 73 years (range 19-107). The most frequent indication was biochemical/imaging suggested biliary disease without jaundice (45.2%; n=122). Three expert endoscopists supervised and performed all ERCPs; in 30.9% of the cases (n=85) a trainee began the procedure. The rate of successful cannulation was 100%. Standard methods alone were used in 66.4% (n=178) and needle-knife fistulotomy was performed in 29.9% (n=80) as a rescue technique. The median overall duration of ERCP was 18 minutes and 47 seconds; biliary cannulation was achieved with a median of 3 minutes and 38 seconds. Eighty patients (28.8%) had the a prominent tubular nonpleated papilla, followed by flat type (20.1%, n=56) and prominent tubular (19.8%, n=55).
Regarding cannulation time, when a trainee started ERCP, the cannulation time lasts on average 4 more minutes compared with no presence of trainee (p<0.000) and when the endoscopist could not move duodenoscope to the desired position in D2, cannulation time was 3 minutes and 36 seconds longer than when the scope could be moved to the desired position in D2 (p=0.004).
When the endoscopist cannot get the papilla in the desired position for cannulation, the probability of having a DBC is 21.63 percentage points higher (p=0.015). Additionally, if the endoscopist cannot move the duodenoscope in the desired position, the probability of having a DBC is 24.05 percentage points higher (p=0.002). If a short position is not possible to achieve, the probability of having a DBC is 53.81 percentage points higher (p=0.018). Furthermore, for each millimeter longer increase of the longitudinal axis of the papilla, the probability of having a DBC increases by 1.63 percentage points (p=0.020). When a trainee starts an ERCP, the probability of the cannulation to be difficult is 22.87 percentage points higher compared with an ERCP without the participation of a trainee (p<0.000).

Conclusion

We have demonstrated that it is possible for an endoscopist to predict a DBC prior to attempting it. This may possibly be useful for the future design of new training programs in ERCP and the development of measures to decrease the rate of PEP.

References

Canena, J., Lopes, L., Fernandes, J. et al. Influence of a novel classification of the papilla of Vater on the outcome of needle-knife fistulotomy for biliary cannulation. BMC Gastroenterol 21, 147 (2021). https://doi.org/10.1186/s12876-021-01735-3

Introduction

Endoscopic retrograde cholangiopancreatography (ERCP) is the gold standard for diagnosing and treating pancreaticobiliary diseases. However, difficult biliary cannulation (DBC) remains a significant challenge in 5–20% of cases. Advanced techniques such as the double guide wire technique (DGT), trans-pancreatic sphincterotomy (TPS), and precut fistulotomy have been developed to address this issue, but their comparative efficacy and safety remain unclear.

Aims & Methods

This study was to compare the success, safety, and time-dependent outcomes of advanced and salvage biliary cannulation techniques (DGT, TPS, and precut fistulotomy) using multivariate and survival analysis. Given that these techniques serve as both initial and salvage approaches after failed primary cannulation attempts, this study provides critical insights into their role in overcoming difficult biliary cannulation.
In this prospective randomized controlled trial, 150 patients with DBC were allocated to DGT (n=50), TPS (n=50), or precut fistulotomy (n=50). Primary outcomes included initial and final cannulation success rates. Secondary outcomes encompass procedural parameters, complications, and hospital stay. Kaplan-Meier survival analysis assessed cumulative success over time, and multivariate logistic regression identified independent predictors of cannulation success and complications.

Results

Initial success rates were 72% (DGT), 68% (TPS), and 68% (precut) (p=0.882). Final success rates reached 100% across all groups after a second attempt. Median first cannulation time was shortest for TPS (17.5 min) and longest for DGT (21 min) (p=0.145). The precut fistulotomy group required significantly less contrast dye (p<0.005). Post-ERCP pancreatitis occurred in 10% (DGT), 22% (TPS), and 24% (precut) (p=0.151), with no significant differences in bleeding, cholangitis, or overall complication rates. Kaplan-Meier analysis demonstrated comparable cumulative success rates (log-rank p=0.882), and CIF analysis confirmed no significant differences in success probability over time. Interaction analysis revealed that operator experience did not significantly modify the effectiveness of any technique (p>0.05).

Conclusion

DGT, TPS, and precut fistulotomy exhibit comparable efficacy and safety in DBC. The choice of technique should be guided by patient-specific factors and endoscopist expertise rather than perceived differences in success or complication rates.

Introduction

Precut sphincterotomy is a technique usually employed for difficult biliary cannulation during endoscopic retrograde cholangiopancreatography (ERCP), it increases the success of deep biliary cannulation, but the method fails at the initial ERCP in 5-12% of cases. Although other invasive strategies are often used to access the bile duct, a second ERCP may be effective and safe.

Aims & Methods

We evaluated the efficacy, safety, and factors related to a second ERCP after failed cannulation using a precut sphincterotomy.

Results

Conclusion

Introduction

Endoscopic retrograde cholangiopancreatography (ERCP) is the gold standard for the treatment of choledocholithiasis. The key step for successful ERCP is selective biliary cannulation, however this fails in about 5-35% of cases. Pre-cut techniques emerged as a rescue for access to the biliary tract. As the length of biliary sphincterotomy after a fistulotomy (NKF) is shorter compared to standard cannulation, there is a theoretical possibility that treatment success will be lower when access is performed by NKF.
In this study, we intend to compare the efficacy and safety of biliary calculi removal between accesses by fistulotomy and standard cannulation.

Aims & Methods

Retrospective cohort study of 379 consecutive patients who underwent ERCP for choledocholithiasis between 2005 and 2022. Patients were selected from a prospective database and allocated into two groups (sample size assuming an effect size of 10%).
179 consecutive patients with choledocholithiasis who underwent NKF after failed cannulation (Group A), compared with 180 patients who underwent standard cannulation (Group B), adjusted for year of ERCP, stone size and number of stones.
Demographic data related to the procedure, adverse effects and the need for a new ERCP were evaluated.

Results

379 patients, 59.1% women, mean age 75.10 (26-97) years. Overall success rate of 87.07% on the CPRE index. 56 patients repeated ERCP with a success rate of 97.89%.
The success rate in group A was significantly lower compared to group B (p<0.003). Adverse events occurred in 6.60% of patients and did not differ significantly between the two techniques (p=0.307). Pancreatitis occurred in 3.7% of patients in group A and 5.1% in group B (p=0.340).
In the regression analysis (table 6) NKF cannulation was associated with a lower stone removal success rate compared with standard cannulation in the initial ERCP (odds ratio [OR] 0.34; 95% CI: 0.14-0.81; p=0.015). Stone size (10-15mm and >15mm) and having 4 or more stones were also predictors for a lower rate of stone removal in the initial ERCP (stone size 10-15 mm: OR 0.20, p=0.000; stone size >15 mm: OR 0.05, p=0.000; 4 or more stones: OR 0.4, p=0.040, respectively).

Conclusion

NKF is a rescue and expertise demanding technique, emerging has a savage approach when standard cannulation fail. However, was less effective than standard cannulation in the treatment of choledocholithiasis. Complications were similar in both groups.

References

Introduction

During endoscopic retrograde cholangiopancreatography (ERCP) for biliary indication, difficult biliary cannulation with an unintended access to the main pancreatic duct (PD) increases the risk of post-ERCP pancreatitis (PEP). Both double guidewire technique (DGW) and transpancreatic biliary sphincterotomy (TPBS) can be performed.

Aims & Methods

The purpose of this prospective, randomized, controlled trial is to compare the technical success and adverse events (AEs) rate of these techniques.

Results

Conclusion

In difficult biliary cannulation, TPBS demonstrated a higher success rate and similar safety profile compared with DGW. there was no difference in PEP rate between TPBS and DGW techniques. TPBS is a good alternative in cases of unintended PD cannulation of difficult cannulation.

Introduction

Improving the biliary cannulation technique in endoscopic retrograde cholangiopancreatography (ERCP), especially for native papilla, is challenging for trainees. Several previous studies have shown that improving it required a large caseload, usually 350–400 cases, or a special education program. Therefore, we created an e-learning educational video series system to allow trainees to learn biliary cannulation anywhere with ease and conducted a multicenter prospective study to evaluate it.

Aims & Methods

We created 27 educational videos containing biliary cannulation for native papilla with explanations. Twelve endoscopists with less than 6 years of ERCP experience at two general hospitals in Shizuoka, Japan, participated in this educational program using an e-learning system. First, each participant performed 10 biliary cannulations of native papillae with a preceptor, followed by e-learning and additional 10 biliary cannulations of native papillae. Data from 120 biliary cannulations each for pre-e-learning (PR) and pro-e-learning (PO) were compared according to comprehension score (CS), difficult cannulation (DC), failed biliary cannulation (FB), and adverse events (AE). CS was given by the preceptor-to-trainee oral test before biliary cannulation (maximum of six points). DC was defined as biliary cannulation time >300 sec, >5 biliary cannulation attempts, and ≥2 unintended pancreatic duct cannulation. The correlation between CS and DC was analyzed using the Cochran-Armitage test for trends, and receiver-operating characteristic (ROC) curves were used to determine CS's cut-off value.

Results

There were no significant differences in age, gender, and benign/malignant status of patients undergoing biliary cannulation between PR and PO groups. The outcomes are shown in the table. CS was higher in the PR group than in the PR group; however, no significant differences in DC, FB, and AE rates were observed between the two groups. There was a negative correlation between CS and DC (P<0.01), and the cut-off value and area under the ROC curve for CS for DC were scored 4 and 0.72 (95% confidence interval: 0.66–0.78), respectively. On per-participant comparison, CS≥4 became higher after e-learning (P=0.04); however, there were no significant differences in DC, FB, and AE rates.

Conclusion

Our e-learning system could help deepen comprehension of papilla but did not significantly reduce DC, UBC, and AEs. E-learning and technical acquisition may be needed to improve biliary cannulation.

References

1. Sachin Wani, Matthew Hall, Andrew Y Wang et al. Variation in Learning Curves and Competence for ERCP Among Advanced Endoscopy Trainees by Using Cumulative Sum Analysis. Gastrointest Endosc. 2016 Apr;83(4):711-9.e11.
2. Brian S Lim, Joseph W Leung, John Lee et al. Effect of ERCP Mechanical Simulator (EMS) Practice on Trainees' ERCP Performance in the Early Learning Period: US Multicenter Randomized Controlled Trial. Am J Gastroenterol. 2011 Feb;106(2):300-6.
3. James G Bittner 4th 1, John D Mellinger, Toufic Imam et al. Face and Construct Validity of a Computer-Based Virtual Reality Simulator for ERCP. Gastrointest Endosc. 2010 Feb;71(2):357-64. doi: 10.1016/j.gie.2009.08.033.