Lithotripsy, the same technology being used at the University of Utah Medical Center to successfully treat kidney stones, is now being utilized to break up gallstones, eliminating the need for surgery.

Gallstones are formed in the gallbladder when cholesterol is not metabolized normally. Nearly 20 million Americans have gallstones. However, each year only a half million of those have symptoms of abdominal pain and require treatment. It is those patients who are candidates for gallstone lithotripsy.Lithotripsy is commonly used in Germany and other parts of Europe to pulverize gallstones. It is being studied closely in the United States pending approval of the federal Food and Drug Administration for general use.

"The University of Utah is part of a multicenter study that will treat 300 individuals before sending the results to the FDA," said Dr. Kenneth Buchi, assistant professor of internal medicine in the Division of Gastroenterology. He and his associate, Dr. Merril Dayton, assistant professor of surgery and a gastrointestinal and colorectal surgery specialist, are principal investigators of the U.'s gallstone lithotripsy studies.

The University of Texas Southwestern in Dallas, Duke University and the University of Iowa also are treating patients. Other centers may soon be added to the trials.

Buchi said only about 15-20 percent of the people with gallstones are candidates for lithotripsy. "We are treating only those people who are suffering symptoms of gallstones," he said. Patients wishing the treatment are tested through X-ray and ultrasound procedures to determine the number and size of the gallstones, and how well the gallbladder is functioning.

"Those patients who have three or fewer stones are accepted for treatment," Buchi said. "The stones must be smaller than 2 centimeters and the gallbladder must be functioning well."

After the stones are broken with the lithotriptor, patients are given Actigall, a medication that dissolves the remaining fragments, which are then passed from the gallbladder.

The cost of the new procedure is $5,000 - about half of the normal cost of surgery. Buchi and Dayton have no statistics on the number of Mountain West area residents with gallstones, but they estimate that about 500 patients per year require treatment. They expect to treat 50 patients in the next six months.

Individuals whose family physicians have confirmed or who suspect they may have gallstones or kidney stones can call the Utah Stone Center at the U. Hospital at 581-4772.