There are now many methods of treating stones in the kidney or ureter. Lithotripsy is one method.
Stones can be broken up by focusing pressure waves onto them from a lithotriptor – this is known as "Shock Wave Lithotripsy" – SWL for short.
A lithotriptor is a machine which has the ability to visualise stones either by x-ray or ultrasound.
The energy waves produced by the machine are accurately focused on the stone and travel through the body tissues without damaging them, the energy is dispersed to break up the stone usually reducing it to ‘sand’ or ‘gravel’ – which is then passed in the urine with little or no pain.
The majority of patients are treated as day cases, spending 2-4 hours in the unit.