What is Extracorporeal Shockwave Lithotripsy?

About ESWL

Extracorporeal shockwave lithotripsy was developed in the 1980s. Prior to this point, open surgery was the only treatment for kidney stones that were too large to pass through the urinary tract. The development of ESWL was therefore a significant milestone in the treatment of the condition.

In fact, ESWL is now the preferred method of treatment for kidney and gallbladder stones. The procedure is almost entirely non-invasive and requires only low-level anesthesia, making it a much safer prospect for a wider range of people. The procedure is safe to use in children, and is safe for people who have only one kidney.

How does it Work?

The ESWL unit uses externally-applied high-intensity acoustic pulses to break up large calcified kidney stones. During the procedure, a patient lies down on a bed, with their back supported by a water-filled device that is situated beneath the kidneys.

Fluoroscopic x-ray or ultrasound is used to detect the location of kidney stones, and help the physician aim shockwave pulses. Shockwaves are generated by using electrical current to generate high pressure energy waves. The energy waves are focused as they are directed at the location of the stones.

ESWL is an out-patient procedure which takes around an hour. Some patients may have sedatives or a local anesthetic during the procedure. Patients can go home after the procedure is over, but may require some help getting home if they receive any kind of sedation.

Around 90% of people with kidney stones of 10 mm or less in diameter end up with stones which can easily pass through the urinary tract after ESWL. The stones pass through the body within days, or a few weeks. They may cause some mild pain as they pass out of the urinary tract and bladder.

Risks and Complications

Women who are pregnant should not undergo ESWL, as the x-rays and sound waves used in the procedure may be damaging to the fetus. People with kidney infections or urinary infections must wait until the infection has subsided before being treated. Abnormal kidney structure or the presence of kidney cancer also precludes ESWL treatment.

Possible complications of ESWL include pain, bleeding, urinary tract infection, and blocked urine flow. Anyone who experiences persistent or severe pain, or prolonged symptoms, following ESWL should seek prompt medical attention.

References

Michael Grasso, MD. Extracorporeal Shockwave Lithotripsy

Monica Rhodes. Reviewed by Adam Husney, MD. Extracorporeal shockwave lithotripsy (ESWL) for kidney stones.