Faculty Bibliography

BACKGROUND AND AIMS: The need for transpapillary drainage (TP) in patients undergoing transmural drainage (TM) of pancreatic fluid collections (PFC) remains unclear. The aims of this study were to compare treatment outcomes between patients with pancreatic pseudocysts undergoing TM versus combined (TM and TP) drainage (CD) and to identify predictors of symptomatic and radiologic resolution. METHODS: Retrospective review of 375 consecutive patients with PFC who underwent endoscopic ultrasound (EUS)-guided TM from 2008 to 2014 at 15 academic centers in the United States. Main outcome measures included TM and CD technical success, treatment outcomes (symptomatic and radiologic resolution) at follow-up, and predictors of treatment outcomes on logistic regression. RESULTS: A total of 375 patients underwent EUS-guided TM drainage of a PFC, of which 174 were pseudocysts. TM alone was performed in 95 (55%) and CD in 79 (45%) pseudocysts. Technical success: TM 92(97%) versus CD 35(44%) (P=0.0001). There was no difference in adverse events between the TM (15%) and CD (14%) cohorts (P=0.23). Median long-term (LT) follow-up after transmural stent removal was 324 days (interquartile range, 72-493 days) for TM and 201 days (interquartile range: 150-493 days) (P=0.37). There was no difference in LT symptomatic resolution (TM: 69% vs CD: 62%, P=0.61) or LT radiologic resolution (TM: 71% vs CD: 67%, P=0.79). TP attempt was negatively associated with LT radiologic resolution of pseudocyst (OR, 0.11; 95% CI, 0.02-0.8; P=0.03). CONCLUSIONS: TP has no benefit on treatment outcomes in patients undergoing EUS-guided TM of pancreatic pseudocysts and negatively impacts long-term resolution of PFC.

BACKGROUND AND AIMS: There are limited data on learning curves and competence in ERCP. By using a standardized data collection tool, we aimed to prospectively define learning curves and measure competence among advanced endoscopy trainees (AETs) by using cumulative sum (CUSUM) analysis. METHODS: AETs were evaluated by attending endoscopists starting with the 26th hands-on ERCP examination and then every ERCP examination during the 12-month training period. A standardized ERCP competency assessment tool (using a 4-point scoring system) was used to grade the examination. CUSUM analysis was applied to produce learning curves for individual technical and cognitive components of ERCP performance (success defined as a score of 1, acceptable and unacceptable failures [p1] of 10% and 20%, respectively). Sensitivity analyses varying p1 and by using a less-stringent definition of success were performed. RESULTS: Five AETs were included with a total of 1049 graded ERCPs (mean +/- SD, 209.8 +/- 91.6/AET). The majority of cases were performed for a biliary indication (80%). The overall and native papilla allowed cannulation times were 3.1 +/- 3.6 and 5.7 +/- 4, respectively. Overall learning curves demonstrated substantial variability for individual technical and cognitive endpoints. Although nearly all AETs achieved competence in overall cannulation, none achieved competence for cannulation in cases with a native papilla. Sensitivity analyses increased the proportion of AETs who achieved competence. CONCLUSION: This study demonstrates that there is substantial variability in ERCP learning curves among AETs. A specific case volume does not ensure competence, especially for native papilla cannulation.

BACKGROUND AND STUDY AIMS: It can be difficult to distinguish adenomas from benign polyps during routine colonoscopy. High resolution microendoscopy (HRME) is a novel method for imaging colorectal mucosa with subcellular detail. HRME criteria for the classification of colorectal neoplasia have not been previously described. Study goals were to develop criteria to characterize HRME images of colorectal mucosa (normal, hyperplastic polyps, adenomas, cancer) and to determine the accuracy and interobserver variability for the discrimination of neoplastic from non-neoplastic polyps when these criteria were applied by novice and expert microendoscopists. METHODS: Two expert pathologists created consensus HRME image criteria using images from 68 patients with polyps who had undergone colonoscopy plus HRME. Using these criteria, HRME expert and novice microendoscopists were shown a set of training images and then tested to determine accuracy and interobserver variability. RESULTS: Expert microendoscopists identified neoplasia with sensitivity, specificity, and accuracy of 67 % (95 % confidence interval [CI] 58 % - 75 %), 97 % (94 % - 100 %), and 87 %, respectively. Nonexperts achieved sensitivity, specificity, and accuracy of 73 % (66 % - 80 %), 91 % (80 % - 100 %), and 85 %, respectively. Overall, neoplasia were identified with sensitivity 70 % (65 % - 76 %), specificity 94 % (87 % - 100 %), and accuracy 85 %. Kappa values were: experts 0.86; nonexperts 0.72; and overall 0.78. CONCLUSIONS: Using the new criteria, observers achieved high specificity and substantial interobserver agreement for distinguishing benign polyps from neoplasia. Increased expertise in HRME imaging improves accuracy. This low-cost microendoscopic platform may be an alternative to confocal microendoscopy in lower-resource or community-based settings.

Given its morbidity and mortality, the early detection and diagnosis of gastric cancer is an area of intense research focus. This article reviews the emerging use of enhanced endoscopic imaging technologies in the detection and management of gastric cancer. The combined use of white-light endoscopy with enhanced imaging technologies, such as magnification narrow-band imaging, chromoendoscopy, and autofluorescence endoscopy, demonstrates promise in the improved ability to detect and delineate gastric neoplasia. However, widespread clinical use is still limited, mainly because of the restricted availability of the technologies.

Confocal laser endomicroscopy allows for in vivo microscopic scanning of the Barrett's segment and might improve the detection of neoplastic lesions. Here the basic principles of this innovative technique are shown and how to differentiate between normal gastric mucosa, nonneoplastic Barrett's mucosa, and Barrett's neoplasia is demonstrated. This article is part of an expert video encyclopedia