SpyGlass Cholangioscopy: Biliary Tract Endoscopy
Cholangioscopy and Biliary Tract Endoscopy: SpyGlass, ERCP, and Advanced Biliary Diagnosis
Cholangioscopy allows direct visualization of the inside of the common bile duct with a miniscope introduced through the duodenoscope channel — the SpyGlass DS II system completely changes the diagnosis of indeterminate biliary strictures and difficult stones
The biliary tract (common bile duct and intrahepatic bile ducts) was for decades a territory that endoscopy could only reach indirectly — through contrast radioscopy in ERCP. Cholangioscopy changed that: it allows direct visualization of the inside of the common bile duct with a 1 mm miniscope introduced inside the duodenoscope channel, obtaining targeted biopsies of suspicious lesions and fragmenting difficult stones with a laser.
1. SpyGlass DS II — the most used cholangioscopy system
2. Indications for cholangioscopy
| Indication | Why cholangioscopy | Diagnostic yield |
|---|---|---|
| Indeterminate biliary stricture | Blind brushing cytology in ERCP has only 30–45% sensitivity for cholangiocarcinoma. SpyGlass-guided biopsy increases sensitivity to 60–75%. | 60–75% sensitivity (vs 30–45% blind ERCP) |
| Difficult common bile duct stones | Stones >2 cm, hard consistency, in patients where the balloon or Dormia basket have failed in previous ERCP. The laser fragments them from the inside under direct vision. | >90% success with SpyGlass laser lithotripsy |
| Cholangiocarcinoma staging | Determines the proximal extent of the biliary tumor — critical for deciding if surgery (hepatectomy with biliary reconstruction) is feasible. | Staging that changes the surgical decision in 30–40% of cases |
Related articles
Sources
- ASGE. Technology Review on Cholangioscopy. asge.org. 2024. ASGE 2024
- ESGE. Guideline on Cholangioscopy. esge.com. 2023. ESGE 2023
- Chen YK et al. SpyGlass DS II — meta-analysis of diagnostic accuracy. Endoscopy. 2024. Chen 2024

