Introduction
In endoscopic retrograde cholangiopancreatography (ERCP)-related procedures, selective biliary cannulation is the most basic procedure and the most difficult to master. The device to improve the success rate of selective biliary cannulation is one of the most awaited innovations in the field of biliopancreatic diseases.
Texture and Color Enhanced Imaging (TXI) is a novel imaging technique that can create enhanced endoscopy images. TXI mode optimizes image structure, brightness, and tonality, the factors that construct and delineate mucosal surface images.
In this study, we aimed to reveal the factors using TXI influencing the difficulty of selective biliary cannulation.
Aims & Methods
This was a multicenter, retrospective study conducted at Kindai University Faculty of Medicine and Saitama International Medical Center.
Patients with naïve papilla for whom selective biliary cannulation was attempted between June and October 2022 were included in this study. A duodenoscope (TJF290V, Olympus Medical Systems, Tokyo, Japan) and EVIS X1 system (Olympus Corporation) were used for ERCP.
Papillary morphology evaluation was performed first with white light imaging (WLI) and then with TXI in all cases, and each evaluation was documented. TXI and WLI were used alternately in each case as the imaging mode during biliary cannulation.
The primary endpoint was the success rate of selective biliary cannulation.
Secondary endpoints included the ability to assess the morphological classification of the papilla, the time required for selective biliary cannulation, and the rate of first-touch cannulation (FTC).
For the morphological classification of the papilla, the agreement rate between the gold standard, as judged by three experienced endoscopists after ERCP, and the evaluation with WLI alone and with TXI were analyzed, respectively.
For the time required for selective biliary cannulation, it was defined as the time from the time the catheter was removed from the scope to the time of successful biliary cannulation. FTC was defined as the first attempt that led to successful biliary cannulation.
Results
Between the two groups of 57 patients in the TXI group and 56 patients in the WLI group, the concordance rate for the morphological classification of the papilla was 0.87 for TXI, better than 0.71 for WLI.
There was no difference between the two groups (TXI vs. WLI) in either the success rate of biliary cannulation (98.3 vs. 98.2%) or time required for biliary cannulation (median) (7.5 vs. 7.0 min), but the rate of FTC tended to be higher in TXI (42.1 vs. 25.0%).
Multivariate analysis (OR (95%CI), p-value) revealed the following characteristics: non-separate type papilla (0.25 (012-0.49), 0.0002), smaller papilla (0.43 (0.18-1.02), 0.083), longer oral protrusion (0.51 (0.35-0.80), 0.0024), and the presence of diverticula (0.52 (0.31-0.86), 0.0071) were factors contributing to a longer time required for biliary cannulation.
In trainee-specific analysis, the overall success rate of biliary cannulation was 69.7% (62/89), whereas the factors contributing to biliary cannulation failure were a long oral protrusion (0.21 (0.07-0.58), 0.0024) and the presence of a diverticulum (0.31 (0.09-1.02), 0.054) in multivariate analysis.
Conclusion
The factors affecting the difficulty of selective biliary cannulation were the non-separate type of papilla, the longer oral protrusion, and the presence of a diverticulum. TXI is expected to contribute to selective biliary cannulation by allowing the endoscopist to more accurately determine whether the papilla is a separate type or not than WLI.
Disclosure
There is no conflict of interest regarding this study.
