The purpose of this study is to describe SpyGlass choledochoscopy in patients with post orthotopic liver transplant (OLT) biliary strictures prior to endoscopic therapy and ductal changes after treatment stents.

A prospective observational clinical study to be conducted in Hospital Israelita Albert Einstein, a large open-access, private tertiary referral center.

Consecutive eligible patients with suspected post OLT biliary complications referred to endoscopic retrograde cholangiopancreatography (ERCP) will be considered to SpyGlass as follows.

In those patients with confirmed biliary stricture, SpyGlass direct choledochoscopy will be performed prior to endoscopic treatment with stents.

After final stent removal, choledochoscopy will be repeated to evaluate biliary ductal mucosa.

Inclusion Criteria:

• Patients referred to endoscopic management for biliary post liver transplant complication without previous treatment

Exclusion Criteria:

• Patients referred to endoscopic management for biliary post liver transplant complication with any previous treatment.
• Below 18 years of age
• Pregnancy