34 patients with difficult upper and middle ureteric stones were treated by antegrade ureteroscopy with ultrasonic lithotripsy over a 2-year period. 14 patients (41 percent) had failed extracorporeal wave lithotripsy and another 20 patients (59 percent) were considered unsuitable for extracorporeal shock wave lithotripsy due either to obstruction associated with urosepsis or renal failure. Thirty patients (88 percent) had large stones with a transverse diameter from 10 to 20mm in size. Thirty-three of the 34 patients (97 percent) were successfully treated by this method with minimal morbidity. Of the 7 patients with residual stones, only one needed transurethral ureteroscopic removal and another by piezoelectric extracorporeal shock wave lithotripsy. This technique is a safe and effective method in removing impacted upper and middle ureteric stones for patients who have failed or are unsuitable for extra-corporeal shock wave lithotripsy treatment.