Clinical predictive value of renalase in post-ERCP pancreatitis.

BACKGROUND AND AIMS: Plasma levels of renalase decrease in acute experimental pancreatitis. We aimed to determine if decreases in plasma renalase levels after ERCP predict the occurrence of post-ERCP pancreatitis (PEP). METHODS: In this prospective cohort study conducted at a tertiary hospital, plasma renalase was determined before ERCP (baseline) and at 30 and 60 minutes after ERCP. Native renalase levels, acidified renalase, and native-to-acidified renalase proportions were analyzed over time using a longitudinal regression model. RESULTS: Among 273 patients, 31 developed PEP. Only 1 PEP patient had a baseline native renalase >6.0 µg/mL, whereas 38 of 242 without PEP had a native renalase > 6.0 µg/mL, indicating a sensitivity of 97% (30/31) and specificity of 16% (38/242) in predicting PEP. Longitudinal models did not show differences over time between groups. CONCLUSIONS: Baseline native renalase levels are very sensitive for predicting PEP. Further studies are needed to determine the potential clinical role of renalase in predicting and preventing PEP.

EUS-guided Gastroenterostomy: A Multicenter International Study Comparing Benign and Malignant Diseases.

BACKGROUND: Endoscopic ultrasound (EUS)-guided gastroenterostomy (EUS-GE) is a minimally invasive therapy for patients with gastric outlet obstruction without the risks of surgical bypass and the limited long-term efficacy of enteral self-expanding metal stent placement. However, due to its novelty, there is a lack of significant data comparing long-term outcomes of patients with EUS-GE, based on the underlying disease. In this study, we compare outcomes of EUS-GE on benign versus malignant indications. METHODS: Consecutive patients from 12 international, tertiary care centers who underwent EUS-GE over 3 years were extracted in a retrospective registry. Demographic characteristics, procedure-related information and follow-up data was collected. Primary outcome was the rate of adverse events associated with EUS-GE and the comparison of the rate of adverse events in benign versus malignant diseases. Secondary outcomes included technical and clinical success as well as hospitalization admission. RESULTS: A total of 103 patients were included: 72 malignant and 31 benign. The characteristics of the patients undergoing EUS-GE is shown in Table 1. The mean age of the cohort was 68 years and 58 years for malignant and benign etiology. Gender distribution was 57% and 39% being females in malignant and benign etiology group, respectively. Clinical success, technical success, average procedure time, and hospital length of stay were similar in both groups. Patients with benign underlying etiology had significantly higher number of surgically altered midgut anatomy (P=0.0379). CONCLUSION: EUS-GE is equally efficient regardless of the underlying etiology (malignant vs. benign), and the adverse events both groups were comparable.

Comorbidities Drive the Majority of Overall Mortality in Low-Risk Mucinous Pancreatic Cysts Under Surveillance.

BACKGROUND & AIMS: The Charlson Comorbidity Index (CACI) has been suggested as a tool to determine comorbidity burden and guide management for patients with mucinous pancreatic cysts (Intrapapillary Mucinous Neoplasms and Mucinous Cystic Neoplasms), but has not been studied well among "low-risk" mucinous pancreatic cysts i.e. without worrisome features (WF) and high-risk stigmata (HRS). This study sought to determine the comorbidity burden among surveillance population of low-risk pancreatic cysts and provide their follow-up mortality outcomes. METHODS: A single center study retrospectively reviewed a prospective pancreatic cyst database and included individuals with low-risk cysts undergoing serial imaging during 2016. Electronic medical records were reviewed to determine their baseline age-adjusted CACI (age-CACI). After 4 years, their progression to WF, disease specific (pancreatic malignancy-related, DSM), extra-pancreatic (EPM), and overall mortalities (OM) were determined using Kaplan-Meir Survival Analysis. RESULTS: 502 individuals underwent prospective surveillance. The study included 440 individuals with low-risk suspected or presumed mucinous cysts and excluded 50 and 12 individuals with WF and HRS respectively. Over a median follow-up of 56 months, 12 WF progressions, 2 DSMs, 42 EPMs, and 44 OMs were observed. Baseline age-CACI had good predictive capacity for 4-year EPM (Area-Under Curve: 0.87; p< .0001). The median age-CACI of 4 enabled cohort stratification into Low (age-CACI <4) and High CACI (age-CACI ≥4) groups. A significantly higher OM (p< .001) was observed among the High CACI group as compared to the Low CACI group. CONCLUSION: Through real-time application of CACI to patient outcomes, our analysis supports incorporation of this comorbidity assessment tool in making shared surveillance decisions among low-risk pancreatic cyst population.

GIE Editorial Board Top 10: advances in GI endoscopy in 2021.

The 9-member Editorial Board of the American Society for Gastrointestinal Endoscopy performed a systematic literature search of original articles published during 2021 in Gastrointestinal Endoscopy and 10 other high-impact medical and gastroenterology journals on endoscopy-related topics. Votes from each editorial board member were tallied to identify a consensus list of the 10 most significant topic areas in GI endoscopy over the calendar year of study, with a focus on 3 criteria: significance, novelty, and global impact on clinical practice. The 10 areas identified collectively represent advances in the following endoscopic topics: colonoscopy optimization, bariatric endoscopy, endoscopic needle sampling and drainage, peroral endoscopic myotomy, endoscopic defect closure, meeting systemic challenges in endoscopic training and practice, endohepatology, FNA versus fine-needle biopsy sampling, endoscopic mucosal and submucosal procedures, and cold snare polypectomy. Each board member contributed a summary of important articles relevant to 1 to 2 of the consensus topic areas, leading to a collective summary that is presented in this document of the "top 10" endoscopic advances of 2021.

Digital single-operator cholangioscopy interobserver study using a new classification: the Mendoza Classification (with video).

BACKGROUND AND AIMS: Digital single-operator cholangioscopy (DSOC) allows direct visualization of the biliary tree for evaluation of biliary strictures. Our objective was to assess the interobserver agreement (IOA) of DSOC interpretation for indeterminate biliary strictures using newly refined criteria. METHODS: Fourteen endoscopists were asked to review an atlas of reference clips and images of 5 criteria derived from expert consensus. They then proceeded to score 50 deidentified DSOC video clips based on the visualization of tortuous and dilated vessels, irregular nodulations, raised intraductal lesions, irregular surface with or without ulcerations, and friability. The endoscopists then diagnosed the clips as neoplastic or non-neoplastic. Intraclass correlation (ICC) analysis was done to evaluate inter-rater agreement for both criteria sets and final diagnosis. RESULTS: Clips of 41 malignant lesions and 9 benign lesions were scored. Three of 5 revised criteria had almost perfect agreement. ICC was almost perfect for presence of tortuous and dilated vessels (.86), raised intraductal lesions (.90), and presence of friability (.83); substantial agreement for presence of irregular nodulations (.71); and moderate agreement for presence of irregular surface with or without ulcerations (.44). The diagnostic ICC was almost perfect for neoplastic (.90) and non-neoplastic (.90) diagnoses. The overall diagnostic accuracy using the revised criteria was 77%, ranging from 64% to 88%. CONCLUSIONS: The IOA and accuracy rate of DSOC using the new Mendoza criteria shows a significant increase of 16% and 20% compared with previous criteria. The reference atlas helps with formal training and may improve diagnostic accuracy. (Clinical trial registration number: NCT02166099.).

Juxta-papillary duodenal diverticula are associated with pyogenic liver abscesses: a case control study.

BACKGROUND: Juxta-papillary duodenal diverticulum (JPDD) has been associated with obstructive jaundice and ascending cholangitis. Potential mechanisms include periampullary colonization of pathogenic bacteria and mechanical obstruction. However, the relation of JPDD with pyogenic liver abscess (PLA) has not been reported. Moreover, approximately one third of patients with PLA have no identifiable risk factors and are labelled as "cryptogenic". We hypothesized that JPDD is an unidentified risk factor for cryptogenic PLA and the aim of this study was to examine this association. METHODS: We conducted a retrospective chart review to identify cases of PLA (n = 66) and compare those to matched controls (n = 66). 66 patients met the study inclusion criteria of a diagnosis of PLA using computerized tomography (CT) imaging and either positive culture or confirmed resolution after antibiotic therapy. Patients with diagnoses of amebic liver abscess, traumatic liver abscess, post cholecystectomy liver abscess, concurrent acute cholecystitis, and hepatobiliary malignancy were excluded. Controls were identified from a radiology database and matched one-to-one with the cases by age and sex. Demographic and clinical data was extracted from electronic medical records. CT scan images of all cases and controls were reviewed by a single expert radiologist to identify the presence of JPDD. Statistical tests including Chi-square and t-test with multiple logistic regression were used to examine the group differences in JPDD and other factors. RESULTS: Among 132 study samples, 13.6% (9/66) of the cases were found to have JPDD, compared to 3.0% (2/66) among controls (p = 0.03). This corresponded to an odds ratio (OR) of 5.05 [OR 5.05; CI 1.05-24.4] on multiple logistic regression analysis. In addition, 1/3rd of PLA cases with JPDD had no other traditional risk factors (cryptogenic PLA). However, a statistically significant association of JPDD with cryptogenic PLA could not be established possibly because of a small number of cases. We found significantly high rate of diabetes mellitus (DM) (42.4%; n = 28/66) among cases compared to controls (21.2%; n = 14/66; p = 0.01). CONCLUSION: We found a significant association between JPDD and PLA. We need studies with larger sample sizes to confirm this relationship and to explore if JPDD could be related to cryptogenic liver abscesses.

Evaluation of socioeconomic and healthcare disparities on same admission cholecystectomy after endoscopic retrograde cholangiopancreatography among patients with acute gallstone pancreatitis.

BACKGROUND: Despite literature and guidelines recommending same admission cholecystectomy (CCY) after endoscopic retrograde cholangiopancreatography (ERCP) for patients with acute gallstone pancreatitis, clinical practice remains variable. The aim of this study was to investigate the role of clinical and socio-demographic factors in the management of acute gallstone pancreatitis. METHODS: Patients with acute gallstone pancreatitis who underwent ERCP during hospitalization were reviewed from the U.S. Nationwide Inpatient Sample database between 2008 and 2014. Patients were classified by treatment strategy: ERCP + same admission CCY (ERCP + CCY) versus ERCP alone. Measured variables including age, race/ethnicity, Charlson Comorbidity Index (CCI), hospital type/region, insurance payer, household income, length of hospital stay (LOS), hospitalization cost, and in-hospital mortality were compared between cohorts using χ2 and ANOVA. Multivariable logistic regression was performed to identify specific predictors of same admission CCY. RESULTS: A total of 205,012 patients (ERCP + CCY: n = 118,318 versus ERCP alone: n = 86,694) were analyzed. A majority (53.4%) of patients that did not receive same admission CCY were at urban-teaching hospitals. LOS was longer with higher associated costs for patients with same admission CCY [(6.8 ± 5.6 versus 6.4 ± 6.5 days; P < 0.001) and ($69,135 ± 65,913 versus $52,739 ± 66,681; P < 0.001)]. Mortality was decreased significantly for patients who underwent ERCP + CCY versus ERCP alone (0.4% vs 1.1%; P < 0.001). Multivariable regression demonstrated female gender, Black race, higher CCI, Medicare payer status, urban-teaching hospital location, and household income decreased the odds of undergoing same admission CCY + ERCP (all P < 0.001). CONCLUSION: Based upon this analysis, multiple socioeconomic and healthcare-related disparities influenced the surgical management of acute gallstone pancreatitis. Further studies to investigate these disparities are indicated.

GIE Editorial Board top 10 topics: advances in GI endoscopy in 2020.

The American Society for Gastrointestinal Endoscopy's Gastrointestinal Endoscopy Editorial Board reviewed a systematic literature search of original endoscopy-related articles published during 2020 in Gastrointestinal Endoscopy and 10 other high-impact medical and gastroenterology journals. Votes from each individual board member were tallied to identify a consensus list of the 10 most significant topic areas in GI endoscopy over the calendar year of study using 4 criteria: significance, novelty, impact on national health, and impact on global health. The 10 areas identified were as follows: artificial intelligence in endoscopy, coronavirus disease 2019 and GI practice, third-space endoscopy, lumen-apposing metal stents, single-use duodenoscopes and other disposable equipment, endosonographic needle technology and techniques, endoscopic closure devices, advances in GI bleeding management, improvements in polypectomy techniques, and bariatric endoscopy. Each board member contributed a summary of important articles relevant to 1 to 2 topic areas, leading to a collective summary that is presented in this document of the "top 10" endoscopic advances of 2020.

Endoscopic Management of Pancreatic Fluid Collections.

Pancreatic fluid collections (PFCs) may develop due to inflammation secondary to acute and/or chronic pancreatitis, trauma, surgery, or obstruction from solid or cystic neoplasms. PFCs can be drained percutaneously, surgically, or endoscopically with endoscopic ultrasound-guided cyst gastrostomy and/or transpapillary drainage through endoscopic retrograde cholangiopancreatography. There has been a paradigm shift in the endoscopic management of PFCs in the past few years with newer techniques including utilization of self-expanding metal stents and multiport devices. This review is a comprehensive update on the classification of PFC, indications for drainage, optimal approach, and techniques.

Can a Computerized Simulator Assess Skill Level and Improvement in Performance of ERCP?

BACKGROUND: Endoscopic retrograde cholangiography (ERCP) is a challenging procedure with considerable risk. Computerized simulators are valuable in training for flexible endoscopy, but little data exist for their use in ERCP training. AIM: To determine a simulator's ability to assess the level of ERCP skill and its responsiveness over time to increasing trainee experience. MATERIALS AND METHODS: In this prospective parallel-arm cohort study, six novice gastroenterology fellows and four gastroenterology faculty with expertise in ERCP completed four simulated baseline cases and the same four cases at a later date. This study took place at a surgical skills center at an academic tertiary referral center. The primary outcome was the total time to complete the ERCP procedure. RESULTS: For the baseline session, experts had a shorter total procedure time than novices (444.0 vs. 616.9 s; least squares mean; p = 0.026). There was no significant difference between experts and novices in the difference of total procedure time between session 1 and session 2 (-200.3 vs. -164.4; least squares mean; p = 0.402). CONCLUSIONS: The simulator was able to differentiate experts from novices for the primary outcome of total procedure time. The simulator was not responsive to an increase in trainee experience over time.

A double-blind, randomized, sham-controlled trial of the effect of a radiation-attenuating drape on radiation exposure to endoscopy staff during ERCP.

OBJECTIVES: Endoscopic retrograde cholangiopancreatography (ERCP) is associated with radiation exposure to the endoscopist and staff that may be significant in high-volume centers. We investigated whether a radiation-attenuating drape over the fluoroscopy image intensifier reduces radiation exposure during ERCP. METHODS: We performed a prospective, randomized, double-blind trial of 100 therapeutic ERCPs at a tertiary-care university center. Procedures were randomly assigned to groups receiving lead-free radiation-attenuating drapes (n=50) or identical sham drapes (n=50). The drapes were suspended around the fluoroscopy image intensifier during ERCP. The primary end point was the effective dose of radiation measured at the endoscopist's eye and neck, and at the assisting nurse's neck. The cumulative annual radiation exposure was also estimated. RESULTS: Fluoroscopy time, absorbed radiation dose, and dose area product were similar in the study groups. Mean effective dose for sham vs. radiation-attenuating drape was 0.21±0.27 vs. 0.02±0.02 mSv at the endoscopist's eye, 0.35±0.44 vs. 0.03±0.03 mSv at the endoscopist's neck, and 0.27±0.34 vs. 0.02±0.02 mSv at the nurse's neck (P<0.0001 for all comparisons). The relative risk reduction in radiation was 90%, 91%, and 93% at the three sites. At a high-volume center in which an endoscopist performs 500 therapeutic ERCPs per year, the estimated cumulative annual effective dose at the endoscopist's eye level is 126 mSv with conventional protection and 12 mSv with a radiation-attenuating drape, with the recommended limit being 20 mSv. CONCLUSIONS: The addition of a radiation-attenuating drape around the image intensifier during ERCP significantly decreases radiation exposure to endoscopists and staff by ∼90%.

Incidence and predictors of post-ERCP pancreatitis in patients with suspected sphincter of Oddi dysfunction undergoing biliary or dual sphincterotomy: results from the EPISOD prospective multicenter randomized sham-controlled study.

BACKGROUND AND STUDY AIM: Pancreatitis following endoscopic retrograde cholangiopancreatography (ERCP) is a significant and potentially life-threatening adverse event and is common in patients with suspected sphincter of Oddi dysfunction (SOD). Here we aimed to identify predictors of the risk in this population. PATIENTS AND METHODS: The Evaluating Predictors and Interventions in SOD (EPISOD) study prospectively enrolled 214 post-cholecystectomy patients with SOD type III in seven US centers. Patients were randomized, using a 2:1 allocation, to sphincterotomy or sham procedure, irrespective of the results of sphincter of Oddi manometry. Patients in the sphincterotomy arm who had elevated pancreatic sphincter pressure were randomized to biliary only or to dual (biliary and pancreatic) sphincterotomy. All but one patient received prophylactic pancreatic stents, but none received pharmacological prophylaxis. Post ERCP pancreatitis (PEP) was defined as acute pancreatitis within the subsequent 7 days. Blinded research coordinators at each site called patients at 1 week post-procedure. RESULTS: PEP occurred in 26 patients, in 10.6 % (15/141) in the sphincterotomy arm and 15.1 % (11/73) in the sham arm; unadjusted relative risk 0.71 (95 % confidence interval [95 %CI] 0.34 - 1.46). PEP rate was not significantly different in patients who received sphincterotomy compared with those undergoing sham treatment. In addition, the proportion was not statistically different in those who received biliary sphincterotomy alone (12/94; 12.8 % [95 %CI 6.0 % - 19.5 %]) compared with dual sphincterotomy (3/47; 6.4 % [95 %CI 0.0 % - 13.4 %]). Multivariate analysis identified an interaction between duration of ERCP and sedation type (P < 0.02). CONCLUSION: The performance of biliary or dual sphincterotomy does not increase the risk of PEP in patients suspected of SOD. However, the high rate of PEP in patients with suspected SOD, despite pancreatic stenting in expert centers, is confirmed in this prospective study. The combined effect of duration of ERCP and sedation type on the development of PEP should be further explored.Clinicaltrials.gov registration: NCT00688662.

Endoscopic treatment of malignant biliary strictures.

Endoscopic stenting is a widely accepted strategy for providing effective drainage in both extrahepatic and intrahepatic malignant strictures. In patients with extrahepatic malignancies, uncovered self-expanding metal stents (SEMS) provide excellent palliation. Hilar malignancies are probably best palliated by placement of uncovered SEMS although some disagreement exists among experts regarding the type and number of stents for optimal palliation. Preoperative biliary drainage (PBD) is commonly performed although a higher risk of complications and the lack of clear benefit raise questions about this practice. Certain groups of patients such as those with markedly elevated bilirubin levels, and in those in whom neoadjuvant therapy is planned, are good candidates for PBD. Considerable controversy exists regarding the optimal method as well as type of stent for PBD in patients with hilar malignancies. Novel endoscopic therapies, including photodynamic therapy and radiofrequency ablation, have emerged as potential adjuvant therapies in the management of malignant bile duct strictures but need further long-term evaluation to establish survival benefit. This review focuses on the current status of endoscopic therapies for malignant biliary obstructions.

Endoscopic management of benign biliary strictures.

Benign biliary strictures are a common indication for endoscopic retrograde cholangiopancreatography (ERCP). Endoscopic management has evolved over the last 2 decades as the current standard of care. The most common etiologies of strictures encountered are following surgery and those related to chronic pancreatitis. High-quality cross-sectional imaging provides a road map for endoscopic management. Currently, sequential placement of multiple plastic biliary stents represents the preferred approach. There is an increasing role for the treatment of these strictures using covered metal stents, but due to conflicting reports of efficacies as well as cost and complications, this approach should only be entertained following careful consideration. Optimal management of strictures is best achieved using a team approach with the surgeon and interventional radiologist playing an important role.

Can patient and pain characteristics predict manometric sphincter of Oddi dysfunction in patients with clinically suspected sphincter of Oddi dysfunction?

BACKGROUND: Biliopancreatic-type postcholecystectomy pain, without significant abnormalities on imaging and laboratory test results, has been categorized as "suspected" sphincter of Oddi dysfunction (SOD) type III. Clinical predictors of "manometric" SOD are important to avoid unnecessary ERCP, but are unknown. OBJECTIVE: To assess which clinical factors are associated with abnormal sphincter of Oddi manometry (SOM). DESIGN: Prospective, cross-sectional. SETTING: Tertiary. PATIENTS: A total of 214 patients with suspected SOD type III underwent ERCP and pancreatic SOM (pSOM; 85% dual SOM), at 7 U.S. centers (from August 2008 to March 2012) as part of a randomized trial. INTERVENTIONS: Pain and gallbladder descriptors, psychosocial/functional disorder questionnaires. MAIN OUTCOME MEASUREMENTS: Abnormal SOM findings. Univariate and multivariate analyses assessed associations between clinical characteristics and outcome. RESULTS: The cohort was 92% female with a mean age of 38 years. Baseline pancreatic enzymes were increased in 5%; 9% had minor liver enzyme abnormalities. Pain was in the right upper quadrant (RUQ) in 90% (48% also epigastric); 51% reported daily abdominal discomfort. Fifty-six took narcotics an average of 33 days (of the past 90 days). Less than 10% experienced depression or anxiety. Functional disorders were common. At ERCP, 64% had abnormal pSOM findings (34% both sphincters, 21% biliary normal), 36% had normal pSOM findings, and 75% had at least abnormal 1 sphincter. Demographic factors, gallbladder pathology, increased pancreatobiliary enzymes, functional disorders, and pain patterns did not predict abnormal SOM findings. Anxiety, depression, and poorer coping were more common in patients with normal SOM findings (not significant on multivariate analysis). LIMITATIONS: Generalizability. CONCLUSIONS: Patient and pain factors and psychological comorbidity do not predict SOM results at ERCP in suspected type III SOD. ( CLINICAL TRIAL REGISTRATION NUMBER: NCT00688662.).

Intraductal radiofrequency ablation for management of malignant biliary obstruction.

Self-expandable metal stents (SEMS) are the current standard of care for the palliative management of malignant biliary strictures. Recently, endoscopic ablative techniques with direct affect to local tumor have been developed to improve SEMS patency. Several reports have demonstrated the technical feasibility and safety of intraductal radiofrequency ablation (RFA), by both endoscopic and percutaneous approaches, in palliation of malignant strictures of the bile duct. Intraductal RFA has also been used in the treatment of occlusion of both covered and uncovered SEMS occlusion from tumor ingrowth or overgrowth. This article provides a comprehensive review of intraductal RFA in the management of malignant biliary obstruction.

Nurse observation during colonoscopy increases polyp detection: a randomized prospective study.

OBJECTIVES: To determine whether a second observer during colonoscopy increases adenoma detection. METHODS: Consecutive patients undergoing screening colonoscopy were prospectively randomized to routine colonoscopy or physician and nurse observation during withdrawal. RESULTS: Of 502 patients, 249 were randomized to routine colonoscopy, and 253 to physician plus nurse observation during withdrawal. A total of 592 polyps were detected, 40 identified by the endoscopy nurse only. With nurse observation, 1.32 polyps and 0.82 adenomas were found per colonoscopy, vs. 1.03 polyps and 0.64 adenomas in the routine group, demonstrating a 1.29-fold and a 1.28-fold increase in the average number of polyps and of adenomas detected, respectively. The overall adenoma detection rate (ADR) was 44.1%, with trends toward increased ADR and all-polyp detection rate with nurse observation. CONCLUSIONS: Nurse observation during colonoscopy resulted in an increase in the number of polyps and adenomas found per colonoscopy, along with a trend toward improved overall ADR and all-polyp detection rate.

Interobserver agreement for confocal imaging of ampullary lesions: a multicenter single-blinded study.

BACKGROUND: Malignant ampullary lesions can be difficult to classify by endoscopy alone. Probe-based confocal laser endomicroscopy (pCLE) permits in vivo assessment of mucosal structures in the gastrointestinal tracts in the real time. AIM: The objective of this pilot multicenter study was to assess the interobserver agreement and variance in interpretation of pCLE of ampullary lesions. METHODS: Twelve pCLE video clips of ampullary lesions were distributed to 6 gastrointestinal specialists at 5 medical centers, blinded to final pathologic results. Six variables were assessed for interobserver agreement using κ statistics. Variables included an epithelial outer border with irregular thickness, dark epithelium without discernable individual cells, heterogenously distributed elongated crypts, reduced number of goblet cells, neovascularization, and final diagnosis. RESULTS: The overall interobserver agreement for all observers was poor to slight for all variables (κ=0.02, 0.05, -0.01, 0.04, 0.018) except for the first variable with fair degree of agreement (κ=0.27). On the basis of experience, 3 observers were classified as less experienced, whereas 3 were classified as most experienced. Upon stratification, the less experienced observers had poor interobserver agreement for all variables, except 1. The most experienced observers had poor agreement for 2 variables, slight agreement for 3 variables, and fair agreement for the final diagnosis variable. CONCLUSIONS: The overall interpersonal agreement on pCLE for ampullary lesions was poor. The interobserver agreement was not substantially improved for experienced raters. Further standardization of pCLE image criteria is needed for ampullary lesions. Standardized training may improve interrater reliability to an acceptable level.

High-definition confocal endomicroscopy of the common bile duct.

BACKGROUND: Probe-based confocal laser endomicroscopy (pCLE) of the common bile duct (CBD) is a new procedure that can be used for assessing indeterminate billiary strictures. The CBD has been examined using the CholangioFlex miniprobe (Mauna Kea Technologies, Paris, France), which has a lateral resolution of 3.5 µm and diameter of <1.0 mm. However, larger-diameter higher-resolution confocal probes are available. We aimed to determine if pCLE of the CBD with the high-definition GastroFlex(UHD) miniprobe (UHDp) was feasible. This probe has a lateral resolution of 1 µm and an outer diameter of 2.6 mm. METHODS: Eleven consecutive patients undergoing endoscopic retrograde cholangiopancreatography for various indications at a single, large, academic center were included in the study. Examination of the CBD was attempted with the UHDp after injection of 2.5 mL of 10% fluorescein. A 0.035 inch guidewire was first placed into the CBD and the confocal probe was subsequently inserted adjacent to the guidewire. Position of the miniprobe was identified fluoroscopically. RESULTS: The GastroFlex(UHD) miniprobe was successfully introduced into the CBD in 10 of 11 patients. Cellular structures and individual cell morphology seemed to be more clearly visualized with the UHDp compared with the CholangioFlex probe. No significant side effects except 1 case of mild pancreatitis. CONCLUSIONS: We demonstrate that high-definition pCLE of the CBD by the GastroFlex(UHD) miniprobe is feasible and may offer improved image quality over the standard CholangioFlex probe. Further studies are needed to see if this improves the diagnostic accuracy of bile duct lesions.

Interpretation of probe-based confocal laser endomicroscopy of indeterminate biliary strictures: is there any interobserver agreement?

BACKGROUND: Probe-based confocal laser endomicroscopy (pCLE) has enabled in vivo histopathology by obtaining high resolution images of the mucosal layers of the gastrointestinal tract. For indeterminate bile duct strictures, biopsy, cytologic brushing and needle aspiration have low levels of diagnostic accuracy. AIM: The objective of this multi-center pilot study was to assess the interobserver agreement in interpretation of pCLE imaging. METHODS: Twenty-five de-identified pCLE video clips of indeterminate biliary strictures were sent to 6 observers at 5 institutions. Miami Classification was used to standardize image interpretation. Seven variables were assessed for interobserver agreement using the Fleiss kappa statistic which included: presence of thick (>20 µm) or thin (<20 µm) dark or white bands, dark clumps, epithelium including glandular structures, interstitial fluorescein leakage, ease of interpretation, and final diagnosis. Based on operator experience, observers were categorized into 3 categories of experience (Category 1: 0-10; Category 2: 11-20; Category 3: >21 cases). RESULTS: Upon stratification, Category 1 interobserver agreement ranged from "Poor" to "Fair" (κ = 0.277, κ = -0.079, κ = -0.025, κ = -0.066, κ = 0.128, κ = 0.088), and for the final diagnosis variable, the agreement was slight (κ = 0.033). Category 2 and 3 interobserver agreement ranged from "Poor" to "Fair" (κ = 0.211, κ = 0.181, κ = 0.347, κ = 0.238, κ = -0.050, κ = 0.092), and for the final diagnosis variable, the agreement was slight (κ = 0.195). CONCLUSION: The overall interobserver agreement for pCLE image interpretation in indeterminate biliary strictures ranges from poor to fair. Interpretation criteria as well as training require further standardization toward improving inter-rater reliability.