Lithotripsy of Gallstones

To the Editor: The carefully conducted study by Schoenfield et al. (Nov. 1 issue) 1 demonstrates that adjuvant bile acid therapy after shock-wave lithotripsy of gallbladder stones enhances the disappearance of fragments significantly. However, even in patients who received ursodiol together with shock-wave lithotripsy, the rate of complete gallbladder clearance was considerably lower than in other studies. 2 3 4 Only 40 percent of their patients with radiolucent stones up to 20 mm in diameter were free of fragments within six months, as compared with 78 percent of comparable patients in our initial series 2 and up to 72 percent in other reports. 3 , 4 These differences . . .