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Updated: Jun 3, 2026

Laparoscopic Cholecystectomy with Indocyanine Green Fluorescence: Choledochoscopic Stone Extraction and Primary Duct Suture
Published on: November 25, 2025
Contrast does not affect cholangioscope image quality
Jeffrey Laczek1, Mark Flasar, Eric Goldberg
1Gastroenterology Service, Department of Medicine, Walter Reed Army Medical Center, Washington, DC, USA.
Background/Aims:
Peroral cholangioscopy is a rapidly evolving technique that allows direct examination of the bile duct. We sought to determine if there was a difference in image quality with the cholangioscope immersed in normal saline compared with radiologic contrast or a mixture of contrast and normal saline.
Methods:
Images were captured using the SpyGlass® cholangioscope system (Boston Scientific Corp.) immersed in solutions ranging from 0 to 100% contrast. The images were then reviewed in a blinded fashion by a panel of 9 endoscopists with experience using the SpyGlass® system. The reviewers scored the quality of each image based on a scale of 0 (extremely poor) to 10 (excellent).
Results:
With the cholangioscope immersed in saline and 100% contrast, the mean image quality scores were 7.6 (95% confi dence interval [CI], 6.7-8.5) and 6.9 (95% CI, 5.8-8.0), respectively. The highest mean image quality score was 7.8 (95% CI, 6.7-8.9), obtained in 70% contrast. No signifi cant difference was noted in mean image quality scores using a one way analysis of variance technique (p=0.414).
Conclusions:
Although there are limitations to ex vivo studies, we encourage endoscopists to use intraductal contrast prior to peroral cholangioscopy, if needed for lesion localization.
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