New Shock-Wave Device : Kidney ‘Stonecracker’ to Make UCLA Debut

A new device that destroys kidney stones without resorting to surgery or drugs will be in use at UCLA’s Clark Urological Center beginning March 1, medical center urologists said Friday.

Called a lithotripter--Greek for “stonecracker”--the $2-million instrument shatters kidney stones by means of a shock wave that pulverizes them without damaging the kidney or other tissues, said Dr. Christian Chaussy, a visiting professor of urology at the UCLA Medical Center.

The device is one of seven in use in this country and the only one in the West, Chaussy said. The urologist was a member of the West German team that developed the stonecracker at the University of Munich.

An estimated 3% or 4% of the U.S population develops kidney stones each year. At least 75% of these people pass the stones spontaneously and need no special treatment. The remainder, or about 200,000 people, become candidates for some type of surgery.

New Stones Develop

Chaussy said that 40% to 50% of the people who require surgery develop new stones and must undergo surgery again. Because repeated operations often result in the loss of the entire kidney, this group of patients forms a significant percentage of people on kidney dialysis, he said.

Although the lithotripter will not prevent new stones from forming, it is expected to prevent loss of kidneys, the urologist said.

In addition, according to Dr. Joseph J. Kaufman, director of the Clark Urological Center, use of the lithotripter will enable patients to return to work and other normal activities much quicker than would be possible after surgery.

To use the lithotripter, the patient is placed in a tub of water. Two electrodes in the bottom of the tub release a spark that generates a shock wave that focuses directly on the stone. The stone is shattered by pressures similar to those that cause windows to break when a fast-flying aircraft sends a sonic boom to the ground.

Idea From Physicists

Between 1974 and 1980, in addition to general urological surgery, Chaussy worked with a team of doctors from the University of Munich and physicists from Dornier System, a German aerospace company, developing the lithotripter. The idea that shock waves might have a medical use came initially from the physicists who had noted that shock waves can destroy materials that are distant from the source of the waves.

Since 1980, when the first human with kidney stones underwent treatment with the device, 2,000 patients have been treated at Munich, Chaussy said. “There is no evidence that any tissues have been damaged,” he said.

Use of the lithotripter in the Unites States was approved last month by the Food and Drug Administration.