Lithotripsy for kidney stones

General Information

Lithotripsy is a non-invasive alternative to surgery for the treatment of kidney stones. It uses carefully focused, high-energy shock waves to disintegrate the kidney stones. Once the stone is disintegrated the sand-like fragments pass out of the body in the urine. Large stones may require more than one lithotripsy treatment. The full medical term for the procedure is extracorporeal shock wave lithotripsy (ESWL), meaning that the shock wave is generated outside of the body. Lithotripsy treatment for kidney stones is arranged through a urologist after tests are carried out to determine suitability for the treatment.

Can All Kidney Stones Be Treated With Lithotripsy?

Lithotripsy may be recommended when a kidney stone is too large to pass on its own, or when a stone becomes stuck in the ureter (the tubes that connect the kidneys and bladder). Lithotripsy is usually not recommended when the kidney stone is greater than 2-3cm in diameter, is particularly dense or is a struvite type stone. These stones may need to be surgically removed.

Conditions that may contraindicate the use of lithotripsy include:

Pregnancy
Aortic aneurysm
Bleeding disorders
Significant obesity
Severe skeletal abnormalities

The Lithotripsy Bus

A mobile lithotripsy unit operates from several hospitals around New Zealand, from Whangarei to Invercargill, on a regular 28-day circuit. This is a specialised bus equipped with a high tech lithotripter unit and sophisticated medical, theatre and imaging equipment. The bus is staffed by radiographers and nursing staff, with the urologist and anaesthetist being supplied by the hospital the bus is visiting. Patient files are stored on a computer at the front of the bus. All x-rays are scanned pre and post procedure and patient information and results are collated for comparison and research.

The Lithotripsy Procedure

Lithotripsy is usually a day stay procedure. Admission to hospital will be required prior to the procedure to enable the patient to be fully prepared for the procedure. It is usual for an x-ray to be taken as part of this preparation to check the position of the kidney stone. Prior to the procedure the patient is not allowed anything to eat or drink for a period of time (usually at least six hours). To ensure the patient remains still during the lithotripsy procedure an anaesthetic is given. This is usually given in the form of intravenous sedation (given through a drip into the hand), though in some cases a general anaesthetic may be recommended.

To allow the shock waves to be transmitted through the skin a rubber pad covered with a special gel is placed against the skin. Using x-ray guidance, the read more