Extracorporeal shock wave lithotripsy (ESWL) essentially involves the use of X-rays or ultrasound to locate the position of the kidney stone. The machine generates shock wave energy which are focused on to the stone. Shock waves breaks the stone into smaller pieces so that it can be passed in the urine. Shock waves are target driven and the energy will focused on to the stone without affecting surrounding structures.
It is done as day care procedure
Very useful for small stones in the kidney
It can also be used to treat residual stones after endoscopy or PCNL procedures