What is Lithotripsy?
Extracorporeal (performed outside of the body) Shock Wave Lithotripsy (ESWL) is commonly referred to just as lithotripsy.
Lithotripsy comes from the Greek words 'lithos' and 'tripsis' and literally means 'stone breaking'. The procedure uses shock waves to break your kidney stones into small sand-like particles that can then pass out of your body through your urine.
Why this procedure?
In those patients who are thought to be good candidates for this treatment, about 70 to 90 percent are found to be free of stones within three months of treatment.
Lithotripsy is most often used on small stones (less then 10mm diameter) in your kidney or upper ureter (the tube that takes urine from the kidney to the bladder). Extracorporeal means that the treatment is carried outside the body, so the real advantage of this treatment is that it is non-invasive, so no surgery is involved.
Alternatives to lithotripsy are surgery or waiting to see if the stones pass out of the body on their own.
What is the procedure
High-energy shock waves, also called sound waves, guided by x-ray or ultrasound, will pass through your body until they hit the kidney stones. If you are awake, you may feel a tapping feeling when this starts. The waves break the stones into tiny pieces that can easily be passed in the urine.
Alternatively, a tube may be placed through your bladder or back into your kidney. This tube will drain urine from your kidney until all the small pieces of stone pass out of your body. This may be done before or after your lithotripsy treatment.
The waves are safe and generally do not damage the tissues they pass through.
The first pressure wave may come as a bit of a shock, but you soon settle down once you get used to the strange feeling and the noise. The pressure waves are given in time to your heartbeat. The treatment is usually moderately uncomfortable, like being firmly tapped, but is usually well tolerated. As the treatment progresses the power is gradually increased, and you feel some discomfort.
Before, during and after the procedure:
Lithotripsy can be performed as an outpatient but usually you will be hospitalised for a day or two. After the treatment you will feel a bit sore and will need to take simple painkillers such as paracetamol for a few days. If you had an injection of painkiller you cannot drive for 24 hours. You may pass some blood and sand in the urine as the shattered stone passes through and comes out.
Lithotripsy does bruise the kidney slightly which causes some blood in the urine, but this is quickly cleared by drinking plenty. There is no evidence to suggest that any long-term damage will be caused to the kidney or any other organ by the pressure waves.
Sometimes bugs are released from the stone when it breaks up which may cause an infection in the urine or blood stream. If you do become feverish or shivery it is important that you get the infection treated by your GP.
Usually the fragments of the disintegrated stone are small enough to pass out in your urine without discomfort. Larger pieces may get stuck in the tube between the kidney and bladder (ureter). This may cause you to feel pain and become unwell, again you will need to get help from your GP.
How do I prevent further stones?
After your stone(s) have been treated, it may be possible to perform a diagnostic examination (M1110) to tell you the type of stones you from and then provide detailed and specific dietary advice to try and prevent recurrence. Unfortunately, once you have had stones you do have a high chance of recurrence (50% at 5 years). Your urologist will look at any specific factors in your blood and urine that may need correction to help prevent future stone formation. This may require modifying dietary factors and increasing the volume of fluid drunk per day. Most stone formers should aim to produce 2-2.5 litres of urine per day – this may require a significant increase to your fluid intake. Your urologist will help you with tips to achieve this.