Laser induced shock wave lithotripsy

Laser induced shock wave lithotripsy has the potential to become a standard procedure in the endourologic management of urinary stone disease. To date, there are two fairly well established laser systems for laser induced shock wave lithotripsy in clinical practice, the Q-switched Nd:YAG and the flashlamp pumped dye laser. The Q-switched Nd:YAG laser (20 ns pulses) is distinguished by the high stone selectivity of its coupler systems, but the necessity of a coupler and its fairly small rate of conversion of light into mechanical energy present a grievous draw back. Furthermore, the minimal outer diameter of the transmission system is 1.8 mm, limiting its range of application. By using longer pulses in the range of 1 - 2 μs that can be produced with both a flashlamp pumped dye or a low-gain solid state laser with the same pulse energies (≈50 mJ) these disadvantages can be overcome.