A lithotripter is a piece of medical equipment that uses sound waves on a patient to break up kidney stones. There are different kinds of kidney stones that form when mineral salts crystallize in the kidney or the ureter. The ureter is the tube that leaves the kidney and carries urine to the bladder. Kidney stones can be very painful and they may restrict urine flow through the ureter. The lithotripter provides a non-surgical means of breaking up the kidney stones into smaller pieces that will pass out of the body naturally.
There are several components that make up the lithotripter. A horizontal table supports the patient and there is an imaging device overhead. The imaging device can be either an x-ray machine or an ultrasound. Underneath the table is a barrel-shaped electromagnetic shock wave emitter (EMSE) that generates shock waves. The shock waves, or sound waves, must travel through water, so during the procedure, the patient is wrapped in a water-filled cushion.
The table on the lithotripter can be tilted at an angle to allow the technician to get the best image of the kidney stone. Once the kidney stone is in focus on the x-ray machine, the EMSE will be focused on the kidney stone as well. The shock waves are directed at the precise location of the kidney stone while the technician watches the stone break into pieces.
Shock waves emitted from the lithotripter range in energy levels from high energy to low energy. High energy waves create strong vibrations and break up the kidney stone, but these waves may be uncomfortable for the patient. Low energy waves are more comfortable, but it may take several sessions to break up the kidney stone.
The procedure to break up the kidney stones is known as lithotripsy and is done as an outpatient procedure. It usually takes about an hour and is most successful on kidney stones that are smaller than 1.2 inches (3 cm). During the procedure, the patient may be given a mild sedative and pain medication. The lithotripter makes noise as the shock waves are emitted and this may be disturbing for the patient.
Since this is a non-invasive procedure, the patient should be recovered in a few days. As the broken pieces of the kidney stone pass through the ureter and into the bladder, the patient may see blood in the urine. This should clear up in a few days. The patient may also be put on antibiotics to prevent infection.