Gallstone disease continues to be a major health problem throughout the world, affecting approximately 10 to 20 percent of the Caucasian population . (See "Epidemiology of and risk factors for gallstones".) Ten percent of patients also have gallstones in their biliary ductal system which, in most cases, can be removed endoscopically .
A variety of methods have been devised for extracting stones 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 . (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".)
Only a few months after the discovery of a new form of stimulated emission in 1960, laser (light amplification of stimulated emission of radiation) devices that were based upon laser light were introduced into the medical arena. Laser light is monochromatic, coherent, and collimated, creating a narrow beam of energy suitable for therapeutic applications in many medical specialities . Laser-tissue interactions produced by medical lasers primarily involve photocoagulation, photothermal ablation (vaporization), and photochemical ablation.
In the field of gastroenterology, these phenomena have been used for a number of applications including palliation of advanced gastrointestinal cancer, curative ablation of early carcinoma or high-grade dysplasia in patients with Barrett's esophagus, and treatment of bleeding peptic lesions or angiodysplasias . (See appropriate topic reviews.) Photodisruption induced by ultrashort pulses of laser light is also gaining wider attention as an effective treatment for intraductal gallstones (picture 1).