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Ureteroscopic treatment of ureteral stones: only an auxiliary measure of extracorporeal shockwave lithotripsy or a primary therapeutic option?

Both extracorporeal shockwave lithotripsy (ESWL) and ureteroscopy are well-established methods in stone treatment; however, the therapeutic procedure in ureteral calculi, especially in the distal third of the ureter, is still controversially discussed. The aim of the present study was to examine the role of ureteroscopy as an auxiliary measure after ESWL and its importance as an alternative therapeutic option in the treatment of distal ureteral stones. Between 1991 and 1994, 115 ureteroscopic procedures in 104 patients with ureteral stones or stone fragments were carried out at our institution. During the same period of time, 1,595 patients with ureteral calculi (in the proximal two thirds of the ureter: n = 956; in the distal third of the ureter: n = 639) were treated with a Dornier HM-3 lithotriptor. In 77 of those 104 patients treated by ureteroscopy, this procedure was indicated as an auxiliary measure after failure of ESWL including 34 out of the 639 patients (5.3%) with stones in the distal part of the ureter. The overall direct success rate during the ureteroscopic stone treatment (including 11 cases with a second procedure) in the proximal, middle and distal third of the ureter was 74, 81 and 92%, respectively. The success rate of primary ureteroscopic removal of distal-third ureteral stones alone was 100% in 27 of these 104 patients. After 3 months the overall stone-free rate of all patients treated with ureteroscopy was 94%. Ureteroscopy appears to be a safe and effective treatment modality, if used as an auxiliary measure after failure of ESWL as well as a primary treatment modality in the case of stones in the distal third of the ureter. On the other hand, ESWL alone is a noninvasive and also successful procedure in treating stones situated in the distal part of the ureter.