Extracorprial Shock Wave Lithotripsy uses sound waves that are focused on the stone. These waves pass easily through the body but are strong enough to break up a kidney stone. Sound waves from a machine called a lithotriptor are focused onto stones in the kidney or ureter.  The waves pass through the body and "shock" the stone, causing it to fragment into small pieces. Because of possible discomfort, patients will receive anesthesia during lithotripsy.  A stent may have to be placed in the ureter through the urethra prior to SWL to help stone fragments pass down the ureter after treatment.

Success rates: 50-80 percent depending on stone size and location.

Possible complications: Bleeding in kidney, obstruction during passage of stone fragments, hypertension, adjacent organ injury and bruising of skin.

Hospital stay and recovery: This is the least invasive intervention and is performed as an outpatient procedure (no overnight hospital stay). Recovery time is short and most people are back to normal activity in a few days.