Shockwave lithotripsy (SWL) is a noninvasive procedure for breaking up kidney stones with high-energy shock waves. SWL is the least invasive and least risky approach to stone treatment.
The term “lithotripsy” combines the Greek words “litho” (stone) and “tripsis” (friction or rubbing). The goal of SWL is to break the stones into tiny fragments that can easily pass through the urinary tract along with urine. Shock wave lithotripsy is the most common type of treatment for removing kidney stones.
Usually, stones that form in the kidneys are small enough to pass through the urinary tract and are excreted (passed) along with urine. The main reasons for undergoing the SWL procedure to treat kidney stones are:
Whether kidney stones can be successfully treated with SWL depends on the size of the stones and their number, position, and type. The hardness and depth of the stone is measured on a CT scan before surgery to predict the likelihood of success.
The procedure produces the best results when the kidney stones are no larger than 1.5 centimeters in diameter. The stones must be visible with an X-ray monitor during the treatment. SWL might not be suitable for patients who are obese or on blood thinners.
SWL generally is performed as an outpatient procedure. The patient usually spends a few hours in the recovery room before going home.
Three months after an SWL treatment, 70-80% of well-selected patients will be stone-free (as seen on follow-up X-rays). The success rate seems to be highest for patients whose kidney stones are found in the upper part of the urinary tract (kidneys and upper ureter, the tubes that carries urine from the kidneys to the bladder). The 20-30% of patients for whom SWL is unsuccessful may require an endoscopic procedure.
Patients who have discomfort or bruising after the procedure may be given pain-relieving medication. Drinking lots of water can help.
Sometimes kidney stones come back after the procedure, and the doctor may recommend other forms of treatment. Pain may last for 4 to 8 weeks after the procedure while the stone fragments continue to pass out of the urinary tract.
SWL should not be performed on patients who:
Your doctor will decide whether it will be safe and effective for you to undergo SWL.
Most people will be able to resume their ordinary daily activities after 1 or 2 days. Patients should drink plenty of water.
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or healthcare provider. Please consult your healthcare provider for advice about a specific medical condition. This document was last reviewed on: 07/12/2017