Gallstone disease continues to be a major health problem throughout the world, affecting approximately 10 to 20 percent of the Caucasian population. Ten percent of these patients have gallstones in their biliary ductal system which, in most cases, can be removed endoscopically [1,2]. (See "Epidemiology of and risk factors for gallstones".)
A variety of methods have been devised for extracting gallstones that are not easily removable using standard methods (ie, a retrieval basket or a balloon). As a general rule, these involve methods to crush or fragment the stone (known as lithotripsy). Examples include mechanical, electrohydraulic, and extracorporeal shock wave lithotripsy [3,4]. (See "Endoscopic management of bile duct stones: Standard techniques and mechanical lithotripsy".)
More recently, lithotripsy has been accomplished using laser light . This topic review will discuss the theoretical background, equipment, indications, technique, and clinical effectiveness of laser lithotripsy. Standard methods for removing gallstones within the biliary system are discussed separately. (See "Endoscopic management of bile duct stones: Standard techniques and mechanical lithotripsy".)
ALTERNATIVES TO MECHANICAL LITHOTRIPSY
Gallstone disease is frequent in most populations throughout the world. Despite advances in the treatment of gallstones, the incidence of clinically apparent common bile duct stones has not declined in recent years. The development of endoscopic sphincterotomy in 1974 revolutionized the ways in which common bile duct stones were treated by permitting stone extraction from the bile duct with the Dormia basket or balloon catheters via a therapeutic side-viewing endoscope [1,6].
Large stones lodged within the bile duct require fragmentation before they can be removed endoscopically. This has been traditionally accomplished using mechanical lithotripsy, which is successful in approximately 90 percent of patients . The advantage of this simple method lies in its ease of use and wide availability . In the remaining 10 percent, gallstones resist conventional fragmentation due to size (>2 cm), consistency (eg, bilirubin stones), anatomical position (eg, impaction), or accessibility (eg, intrahepatic stones) . Shock wave technology circumvents many of these limitations. Shock waves can be generated outside the bile duct (extracorporeal shock wave lithotripsy) and within the bile duct using electrohydraulic or laser technology [9,10]