Extracorporeal Shock Wave Lithotripsy (ESWL) for Kidney Stones

Kidney stones are a fairly common occurrence and affect hundreds of thousands of people every year. They are made of salts and other minerals found in the urine that bind together and form small pebble-like debris. They have been found as small as grains of sand or big as golf balls. They can either stay in your kidneys or travel out of your body through the urinary tract. When a stone travels through the small tube that delivers urine out of the body, known as the ureter; it may cause no pain or it can be among the most painful experience.

While there are many types of treatments, an especially effective course of action is extracorporeal shock wave lithotripsy. Also known as ESWL uses shock waves to disintegrate a kidney stone into smaller pieces that can more easily travel through the urinary tract. The procedure itself lasts approximately an hour and includes the following steps:

While the patient lies on a water-filled pad, the doctor will utilize an x-ray to target the stone. Once the location is determined, high-energy sound waves bombard the stone break it into small pieces. These smaller particles then move through the urinary tract and out of the body.

The patient will most likely be administered sedatives and a local anesthesia.
If a very large stone presents during the examination, the physician may use a stent to hold open the ureter and facilitate the passing of the stone.

Usually, ESWL is performed on an outpatient basis an outpatient procedure and the patients return home the same day. After an ESWL session, stone fragments will pass for a few days and may cause mild pain. Larger stones may even require an additional shock wave treatment. This procedure may work best for stones in the kidney or in the ureter that is located close to the kidney. In these instances, the surgeon may try to relocate the stone back into the kidney with a small instrument known as an ureteroscope and then break it apart.

While this is an incredibly effective treatment for most instances of kidney stones, ESWL is usually not employed in the following situations:

  • Pregnant women: because the sound waves and X-rays may be harmful to the fetus.
  • Present with a bleeding disorder.
  • Have a kidney infection, urinary tract infection or kidney cancer.
  • Have kidneys with abnormal structure or function.

Many research studies have demonstrated the efficacy of shock wave therapies to mitigate kidney stones. Ninety percent of patients studied reported having no pain or other symptoms when ESWL was used when the stones were smaller than 10 mm.
Whenever a medical procedure must be performed, even if it minimally or non-invasive such as a shock wave therapy, there risks that need to be considered.

Complications of ESWL include:

  • Onset of pain caused by the passage of stone fragments.
  • Stone fragments can block the urinary tract and restrict urine flow. In these cases, the fragments will be removed with an ureteroscope.
  • Developing a urinary tract infection.
  • Hemorrhage around the kidney.