Prospective Evaluation of the Ability of Spyglass Cholangioscopy to Facilitate Radiation Free ERCP for non-complex bile duct stone disease.

Inclusion Criteria:

1. Age 18 and above
2. Non-complex biliary stone disease involving stones in the common bile or common hepatic duct.
3. Patient has undergone non-invasive imaging (abdo US, MRCP etc) which clearly delineates bile duct diameter and suggests non complex biliary stone disease.
4. Willing and able to comply with the study procedures and provide written informed consent to participate in the study.

Exclusion Criteria:

1. Age <18
2. Potentially vulnerable subjects including, homeless people, pregnant females, employees and students.
3. Participation in another related investigational study that could affect the results of this study within the previous 30 days
4. Complex biliary stone disease cases with unusual location of the stones (intra hepatic, cystic duct, stone proximal to bile duct stricture)
5. Known bile duct infection (cholangitis defined as ongoing fevers on the day of the ERCP procedure or purulence evident at the ampulla or bile duct on cannulation/sphincterotomy. If clear bile is aspirated during the study procedure, we will proceed according to study procedures. If purulence is detected upon aspiration of bile during the procedure, patient will be excluded from the study and undergo standard radiation-based ERCP rather than cholangioscopy.)

5) Complex post-surgical anatomy e.g. Billroth type II anatomy, Roux-en-Y-gastrojejunostomy