endoscopic gallstone removal
Last reviewed 01/2018
Endoscopic stone extraction from the biliary tree may be carried out after adequate sphincterotomy has created an opening wide-enough for stone passage. Stones larger than 1.5cm require means of fragmentation before removal is attempted. This may entail chemical dissolution through a catheter, i.e. methyltertbutylether (MTBE) for cholesterol stones, or lithotripsy, e.g. endoscopic electrohydraulic, endoscopic pulsed laser, or extracorporeal shock wave means.
For smaller stones within the common bile duct, a balloon- tipped catheter is passed beyond their site, distended, and then pulled proximally. The effect is to push the stones out into the duodenum. Alternatively, a 'Dormia' type wire basket can be used. It is pushed past the stones and then opened. It is then pulled proximally to trap the stones.
If a stone is left in situ, both nasobiliary catheters and biliary stents have been used successfully to permit drainage for different durations.