Kidney Stone crusher

What is shock wave lithotripsy?

Shock Wave Lithotripsy (SWL) is the most common treatment for kidney stones in the U.S. Shock waves from outside the body are targeted at a kidney stone causing the stone to fragment. The stones are broken into tiny pieces. lt is sometimes called ESWL: Extracorporeal Shock Wave Lithotripsy®.

These are what the words mean:

• extracorporeal: from outside the body
• shock waves: pressure waves
• lithotripsy (the Greek roots of this word are “litho” meaning stone, “tripsy” meaning crushed)

So, SWL describes a nonsurgical technique for treating stones in the kidney or ureter (the tube going from the kidney to the bladder) using high-energy shock waves. Stones are broken into “stone dust” or fragments that are small enough to pass in urine. lf large pieces remain, another treatment can be performed

When can SWL be used?

SWL works better with some stones than others. Very large stones cannot be treated this way. The size and shape of stone, where it is lodged in your urinary tract, your health, and your kidneys’ health will be part of the decision to use it. Stones that are smaller than 2 cm in diameter are the best size for SWL. The treatment might not be effective in very large ones.

SWL is more appropriate for some people than others. Because x-rays and shock waves are needed in SWL, pregnant women with stones are not treated this way. People with bleeding disorders, infections, severe skeletal abnormalities, or who are morbidly obese also not usually good candidates for SWL. lf your kidneys have other abnormalities, your doctor may decide you should have a different treatment. lf you have a cardiac pacemaker, a cardiologist will decide if you can have SWL.

Is it urgent that the patient be treated with a procedure like this?

lf the stone does not pass on its own, it will require treatment. lf you have an infection, severe pain, or if your kidney function is threatened, your doctors will act quickly. lf you only have one kidney or have had a kidney transplant, your stone will be treated more quickly. lf you have large stones or stones in both kidneys, your doctors will not wait to treat you.

What does the treatment involve?

You will be positioned on an operating table. A soft, water-filled cushion may be placed on your abdomen or behind your kidney. The body is positioned so that the stone can be targeted precisely with the shock wave. In an older method, the patient is placed in a tub of lukewarm water. About 1-2 thousand shock waves are needed to crush the stones. The complete treatment takes about 45 to 60 minutes.

Sometimes, doctors insert a tube via the bladder and thread it up to the kidney just prior to SWL. These tubes (called stents) are used when the ureter is blocked, when there is a risk of infection and in patients with intolerable pain or reduced kidney function.

After the procedure, you will usually stay for about an hour then be allowed to return home if all goes well. You will be asked to drink plenty of liquid, strain your urine through a filter to capture the stone pieces for testing, and you may need to take antibiotics and painkillers. Some studies have reported stones may come out better if certain drugs (calcium antagonists or alpha-blockers) are used after SWL.