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Treating Kidney Stones: Shock Wave Lithotripsy

Shock Wave Lithotripsy

Shock Wave Lithotripsy (SWL) is a treatment for kidney stones that uses sound waves to break stones into smaller pieces. It is by far the least invasive surgical approach and can be the ideal approach, depending on stone size and location. It has traditionally carried lower stone free rates for larger stone, though. The procedure is typically an outpatient one.

The ideal SWL stone is less than 1.5 cm and located in either the kidney or upper ureter. The stone must be visible on a plain film xray (some stones can only be seen by CT imaging).

What to Expect From SWL

Shock Wave Lithotripsy Machine

Certain medications that must be discontinued, since they increase the risk of internal bleeding. The procedure requires general anesthesia and takes approximately 1 hour with subsequent post-operative recovery. You will go home the same day and return to the clinic six weeks later. Post operative pain is variable and oral medications will be given prior to discharge. Some people don't experience any discomfort. Passage of sand-like particles is common as the minuscule stone fragments will pass over the 6 weeks of post-operative recovery. Typically, people can return to work in two days.


Stone free rates are quite variable and range from 67-86 percent. Although SWL is the least invasive procedure for treating kidney stones, it also has an accepted lower success rate. It is nevertheless a reasonably successful procedure with little side effects. The non-invasive nature of SWL makes it an attractive option for patients.


SWL is a very safe procedure. Nevertheless complications include but are not limited to infection, bleeding, need for transfusion (<1 percent) and the risk of additional procedures to completely remove kidney stones. There is some new medical literature that suggests that SWL may be a risk factor for either high blood pressure and/or diabetes mellitus, though there is also medical literature that does not support this theory. No definitive conclusions have been made regarding this particular risk.

​Appointments & Referrals


Kidney Stone Specialists