Fig. 2From: Clinical value of DPOC for detecting and removing residual common bile duct stones (video)Overtube assistance method. a ultraslim endoscope reached the descending portion of the duodenum but unable to enter the common bile duct because it coiled in the greater curvature of the stomach (yellow arrow); b overtube was installed in vitro, black arrow show the oral balloon; c ultraslim endoscope and overture were inserted again, the balloon was inflated after the ultraslim endoscope entered the duodenum, then the ultraslim endoscope was straightenedBack to article page