Probe-based confocal laser endomicroscopy for indeterminate biliary strictures: refinement of the image...

Area of Science:

• Gastroenterology
• Medical Imaging
• Endoscopy

Background:

• Accurate diagnosis of indeterminate biliary strictures remains challenging.
• Current tissue confirmation methods during ERCP have low sensitivity and accuracy.
• Probe-based confocal laser endomicroscopy (pCLE) shows high sensitivity but low specificity for malignant strictures.

Purpose of the Study:

• To validate the Paris Classification for diagnosing inflammatory biliary strictures using pCLE.
• To assess the impact of the Paris Classification on pCLE diagnostic accuracy and specificity.

Main Methods:

• Six pCLE experts applied the Paris Classification criteria to 40 pCLE sequences.
• Criteria included white bands, granular patterns, scale spacing, and reticular structures.
• Interobserver agreement was assessed on a separate set of 18 pCLE sequences.

Main Results:

• Overall accuracy was 82.5% for retrospective diagnosis and 81% for prospective collection.
• Specificity increased to 83.3% compared to 67% in the prospective study.
• Sensitivity was 81.2%, with fair interobserver agreement (k=0.37).

Conclusions:

• The Paris Classification enhances the specificity of pCLE for characterizing indeterminate bile duct strictures.
• This approach improves diagnostic accuracy without negatively impacting overall performance.
• pCLE with the Paris Classification offers a more reliable tool for biliary stricture diagnosis.