The purpose of this study is to assess the interobserver agreement (IOV) for pancreatico-biliary Volumetric Laser Endomicroscopy (VLE) de-identified clips using the new VLE criteria.

This is an Interobserver study to validate VLE criteria for indeterminate biliary and pancreatic duct strictures and evaluate impact on clinical management.

Objective: Validate diagnostic impact of VLE diagnostic accuracy on clinical management

Primary Objectives:

1. Interobserver study for criteria validation and accuracy, Positive predictive value (PPV) and Negative predictive value (NPV), sensitivity and specificity.
2. Evaluation of VLE diagnostics on clinical management (increased accuracy/faster detection)
3. Determination of learning curve to standardize credentialing for endoscopists to use and interpret VLE imaging for biliary/pancreatic treatment management.

B. Hypotheses / Research Question(s) The new VLE criteria for biliary and pancreatic duct strictures increase accuracy, thus leading to substantial impact on clinical management (Screening and Treatment)

Study Design (2 phase):

• Phase 1: Primary Objective 1 and 2 part of the study will be completed.
• Phase 2: Primary Objective 3 of the study will be conducted within 1 month.

Study Timeline: 3 months post WIRB approval. Sample size: 40 VLE Clips of at least 20 seconds featuring one or more the VLE criteria. All clips will have confirmed diagnosis for accuracy analysis. All clips will be de-identified. All clips will be removed from RedCAP and other secure cloud storage upon completion of study.

Clips will be supplied by NinePoint Medical, the company behind VLE OCT. All VLE clips will be from a dataset of clips collected from adults > 18 and who underwent Endoscopic retrograde cholangiopancreatography (ERCP) with indeterminate biliary stricture indications. The clips are chosen based on the quality of the clips, duration, final diagnosis and presence of either benign or malignant criteria.

Investigators: Up to 30 Expert and non-expert endoscopists currently using VLE

Inclusion Criteria:

VLE clips featuring indeterminate biliary or pancreatic duct stricture with confirmed diagnosis on pathology -

Exclusion Criteria:

-

VLE clips featuring indeterminate biliary or pancreatic duct stricture with confirmed diagnosis on pathology.

Endoscopists who use VLE to diagnose indeterminate biliary or pancreatic duct strictures.