The SpyGlass system (Boston Scientific) is a recently developed system for performing cholangioscopy, the visual examination of the bile ducts. This procedure has been performed since 1976, but prior to the development of the SpyGlass system, the endoscopes used for cholangioscopy were very fragile and difficult to use. The SpyGlass system, which is more practical and an improvement over standard endoscopes, was approved by the US Food and Drug Administration in November 2006.