Endoscopy 2012; 44(04): 383-388
DOI: 10.1055/s-0031-1291822
Endoscopy Essentials
© Georg Thieme Verlag KG Stuttgart · New York

Biliary endoscopic retrograde cholangiopancreatography

S. Irani
1  Digestive Disease Institute, Virginia Mason Medical Center, Seattle, Washington, USA
,
T. H. Baron
2  Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota, USA
› Author Affiliations
Further Information

Publication History

Publication Date:
21 March 2012 (online)

Single-operator cholangioscopy in patients requiring evaluation of bile duct disease or therapy of biliary stones (with videos) (Chen et al., Gastrointest Endosc 2011 [1])

Direct visualization of the biliary tree by transpapillary cholangioscopy can be helpful for establishing the diagnosis of indeterminate biliary strictures by visual inspection, for obtaining biopsies, and for guiding bile duct stone therapy [2] [3] [4]. Although the first use of peroral cholangioscopy was described in the 1970 s, its widespread adoption has been limited by the cost and fragility of cholangioscopes, their technology (difficulty with irrigation, limited tip deflection, and suboptimal optics), and the need for two operators [1]. The single-operator cholangioscopy (SOC) system (SpyGlass Direct Visualization System; Boston Scientific Corp., Natick, Massachusetts, USA) was designed to overcome such limitations [5] [6]. The system features two separate irrigation channels, 4-way tip deflection for better steerability, and with the system secured to the duodenoscope handle cholangioscopy can be performed by a single operator. Thus far there are limited data demonstrating improved patient outcomes, and the advanced endoscopic skill required in these complex cases has limited both the potential for prospective data collection and replication of the initial prospective results from the initial single institution [7]. The later study by Chen et al., [1] was a large scale, multicenter, prospective, observational study of SOC procedures and was conducted to provide confirmatory evidence that direct visualization is valuable in the diagnosis of biliary disease and the treatment of choledocholithiasis.

A total of 297 patients underwent SOC (diagnostic indications in 226, stone therapy in 66, primary site of interest unable to be accessed in 5); 93 % completed the study (of those who did not, 11 died, 7 were lost to follow-up, and 2 withdrew). Success rates, adverse events, and the sensitivity and specificity of visual impression and SOC-directed biopsies were reported. Success was defined for non-stone cases as the ability to visualize target lesions and, if indicated, to perform biopsies; for stone cases, success was defined as the ability to identify and initiate stone fragmentation and removal. The overall success rate was 89 % (95 % confidence interval [CI] 84 % – 92 %). Adequate tissue for histological evaluation was obtained in 88 % of 140 patients who underwent biopsy. The sensitivity for the diagnoses of malignancy was 78 % by visual impression and 49 % for SOC-directed biopsy, with respective specificities of 82 % and 98 %. Sensitivity was higher for intrinsic bile duct malignancies (SOC visual impression 84 %, SOC-directed biopsy 66 %) than for extrinsic cancers (62 % and 8 %, respectively). Diagnostic SOC procedures altered clinical management in 64 % of patients. Procedural success was achieved in 61 /66 patients (92 %) with bile duct stones, with complete stone clearance achieved in one session in 71 %. The incidence of serious procedure-related adverse events was 7.5 % for diagnostic SOC and 6.1 % for SOC-directed stone therapy.

This large, multicenter study, which included 10 centers from the USA and five from Europe, demonstrated an 89 % overall success rate, the value of direct cholangioscopy, and reproducibility when used by expert endoscopists in tertiary centers. SOC altered management in nearly two-thirds of patients, similar to the results from a previously published retrospective study from three US centers [8]. However, the exact visual features that allow differentiation of benign from malignant lesions using this device are yet to be determined. In our experience, the optical images obtained with the cholangioscope system that was used in this study, are often suboptimal and can make determination of benign and malignant disease by visual inspection alone very difficult, and narrow band imaging (NBI) is not available with this system. One advantage of the system, however, is that the optical probe can be passed through a standard biliary catheter to allow inspection alone ([Fig. 1]) [9]. Though this reduces cost, tissue acquisition is of paramount importance and SOC-directed biopsies yielded good or excellent specimens in 75 % of cases in the present study, which was the first to demonstrate (not surprisingly) that the sensitivity of forceps biopsy was far higher for intrinsic (66 %) than extrinsic (8 %) cancers. The utility of SOC in the management of difficult stones was also demonstrated in 92 %, with complete stone clearance in 71 %, which was similar to a prior feasibility study in 22 patients with bile duct stones that could not be extracted using mechanical lithotripsy. SOC was also able to detect 11 % of stones that were missed at endoscopic retrograde cholangiopancreatography (ERCP).

Zoom Image
Fig. 1 Cholangioscopy with SpyGlass probe passed through a double-lumen endoscopic retrograde cholangiopancreatography catheter, which showed a polypoid cholangiocarcinoma (thick arrow). Taken from [9].

A significant limitation of this study was the lack of a control group to compare SOC in detection of malignancy vs. other modalities, such as brush cytology using fluorescent in situ hybridization (FISH) [10], endoscopic ultrasound (standard and/or intraductal) and, more recently, confocal laser endomicroscopy [11] [12]. In addition, patients with large stones could have had similar outcomes using large diameter balloon dilation alone or combined with mechanical lithotripsy and/or extracorporeal shock wave lithotripsy. The applicability and results using this device in non-tertiary referral community centers has also yet to be proven. Nevertheless, SOC was associated with high procedural success and low complication rates. With future technical refinements and increasing experience interpreting images, the appeal and applications of cholangioscopy are likely to increase.