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Confirmation of a rubber band as the stone nuclei within common bile duct stones using cholangioscopy

THE PRESENCE OF a foreign body in the common bile duct (CBD) is rare. A 73-year-old Japanese woman presented with epigastric pain. Three years earlier, she had undergone endoscopic treatment, including endoscopic sphincterotomy, stone extraction, and a cholecystectomy operation for bile tract stones. At present, abdominal computed tomography revealed a dilated CBD with stones (CBDs) having a maximum diameter of 43.2 mm (Fig. 1). During the first session, since the CBDs were large, they could not be crushed and retrieved using endoscopic mechanical lithotripsy (EML) devices completely. We performed electrohydraulic lithotripsy using peroral cholangioscopy (SpyGlass System; Boston Scientific, Natick, MA, USA) during the second session. Cholangioscopy revealed a string-like artifact within the fragmented CBDs (Fig. 2a). During the procedures (Fig. 2b), the artifact was visible on the cholangioscopic image (Fig. 2c). After smaller CBDs fragments were formed, they were retrieved with an EML device using a duodenoscope. The EML device (Fig. 2d) revealed a rubber band within the fragmented CBDs (Fig. 2e,f). The procedure was performed without any complications, and the clinical course was uneventful. Thereafter, the patient revealed that she had previously swallowed a rubber band used to package octopus balls (Video S1). We believed that the CBDs had a nucleated rubber band, and this was confirmed and retrieved using peroral cholangioscopy. Hirata et al. summarized previously published cases of CBD foreign bodies and identified 63 cases with the following causes: iatrogenic (66.7%), oral ingestion (27.0%), extracorporeal penetration (1.6%), and parasites (4.8%). To our knowledge, this is the first report of CBDs formed with rubber bands as the nuclei that was identified and successfully treated using peroral cholangioscopy. Patient consent was obtained for publication. Authors declare no conflict of interest for this article. Figure 1 A 73-year-old Japanese woman presented with epigastric pain. Abdominal computed tomography showing a dilated common bile duct with stones having a maximum diameter of 43.2 mm.