Lithotripsy is a treatment for renal calculi (kidney stones). It involves using focused pulses of ultrasound, or in some cases lasers, to shatter kidney stones that are too large for the body to easily pass on its own. It is the second-least intrusive treatment for kidney stones. Most kidney stones are small enough for the body to “pass” the stone on its own without any treatment beyond monitoring and pain management. For larger stones that present greater problems, lithotripsy is usually the first resort of medical treatment.

The Process

There are two types of lithotripsy, called extracorporeal shock wave lithotripsy (ESWL) and laser lithotripsy. Both types of lithotripsy seek to break kidney stones into smaller fragments that can then pass through the urinary tract and be removed from the body. ESWL is considered a non-invasive surgical procedure, while lather lithotripsy is considered minimally-invasive.

Extracorporeal Shock Wave Lithotripsy

In ESWL, the patient may be sedated or under local anesthesia and lies down in the bed that is a part of the ESWL apparatus, with the back supported by a water-filled device placed at the lower back, where the kidneys are located. The kidney stone to be treated is located using ultrasound or a fluoroscopic X-ray. A device delivers an acoustic pulse (repeated sound waves) to the kidney stone. If the treatment is successful, the stone will be broken into smaller fragments and, over the next few days, will be passed from the body in the urine. ESWL is the least invasive of the active treatments used for kidney stones, but it has a lower success rate than more invasive procedures such as laser lithotripsy.

Laser Lithotripsy

Laser lithotripsy employs a scope inserted into the urinary tract. The scope may be a ureteroscope, cystoscope, nephroscope or renoscope. Medical imaging may help in the location of the kidney stone as with ESWL. When the stone is located, a fiber optic channel for laser light is inserted through the scope itself, and laser pulses are delivered to the stone to shatter it into smaller pieces that can be passed through the urinary tract. This is a minimally-invasive procedure that, although it is considered surgery, does not involve making incisions in the body.

Risk Factors

In both types of lithotripsy, the passage of the stones through the urinary tract may involve varying levels of pain. ESWL can result in capillary damage from the sonic bursts and lead to subcapsular hemorrhage and possibly to renal failure. Complications of laser lithotripsy come from the use of the urinary tract scope and are similar to risks involved with any procedure employing such a scope, i.e. it is possible to damage the urinary tract physically.

Cost

The cost of lithotripsy procedures can vary widely. In some areas in the United States, the procedure costs under a thousand dollars, but it can cost as much as three thousand dollars or more. Lithotripsy procedures are covered under many health-care insurance plans, so the cost to the patient may vary even more widely.

Alternatives

As stated above, in most cases kidney stones require no aggressive treatment at all but are passed naturally, and a physician will monitor the progress of the disease and prescribe medications as necessary for pain management. Lithotripsy is the least invasive form of active treatment beyond monitoring and pain management and will be used for kidney stones that are too large to pass unaided but small enough for the treatment to be likely to succeed (usually two to four centimeters in diameter). Other procedures besides lithotripsy may be used when the kidney stone is too large to make lithotripsy likely to succeed.

Laporascopic Surgery (percutaneous nephrolithotomy)

Percutaneous nephrolithotomy is a more invasive surgical procedure that physically removes kidney stones from the body. It makes use of a laporascope to minimize the incision made in the body; this form of surgery is sometimes called “keyhole” surgery. Percutaneous nephrolithotomy is appropriate when the stone is too large for treatment with lithotripsy to be likely to succeed, and when it is located near the pelvic region. The procedure may be done under local or general anesthesia. The advantage of keyhole surgery is that it reduces post-surgical pain and recovery time.

Open Surgery (nephrolithotomy)

Open surgery, or standard nephrolithotomy, is recommended in cases of large kidney stones where the positioning of the stone does not lend itself to treatment by percutaneous nephrolithotomy. A larger incision is made and the kidney stone is surgically removed from the body. This is the most invasive procedure for treatment of kidney stones and is recommended only when other treatments are unlikely to be of success. As with other surgical procedures, possible complications include infection, damage to the kidneys and the urinary tract resulting from the surgery itself, and severe bleeding.