To determine the factors influencing on stone fragmentation and the appropriate session for changing treatment modality of ureteral calculi refractory to in situ ESWL, we analyzed 369 patients with ureteral calculi primarily treated by second-generation lithotripter, Siemens Lithostar from March,1989 to December, 1993. The results obtained were as follows: 1.Three hundred and forty two(92.7%) of the total 369 patients were ultimately free of stones by repetitive performance of in situ ESWL ranging from the first session to the tenth session. 2. The cumulative stone-free rates of the first, second and third session were 64%, 81% and 88%, respectively, and the increment of cumulative stone-free rate thereafter with further repeated in situ ESWL was minimal(p<0.01). 3. According to the location of stone, the cumulative stone-free rate at third session was 89%, 87% and 86% in proximal, middle and lower ureter stones, respectively(p>0.05). 4. According to the size of stone, the cumulative stone-free rate at third session was 100%, 90%, 87%, 70%, 67%, 50% in stones less than 5 mm, 6-10 mm, 11-15 mm, 16-20 mm, 21-25 mm and above 25 mm, respectively(p<0.001). 5. According to the radio-opacity of stone, the cumulative stone-free rate at third session was 96% in stones with minimal opacity, 94% with moderate opacity and 70% in highly opaque stones(p<0.001). 6. According to the degree of ureteral obstruction due to stone, the cumulative stone-free rate at third session was l00% without ureteral obstruction, 80% with mild, 57% with moderate, 67% with severe ureteral obstruction, and it was 50% in patients with non-visualization of the kidney(p<0.05). From these observations, it could be concluded that the factors influencing on stone fragmentation were the size of calculi, radio-opacity and the degree of ureteral obstruction, whereas the location of the ureteral calculi did not influence on the cumulative success rate of repetitive in situ ESWL. Also, it is preferable to restrict the repetitive sessions of in situ ESWL within third session in patients with the ureteral calculi refractory to in situ ESWL, and early change of surgery would be retreatment modality either to ureteroscopic manipulation or to open commended if there are risk factors listed above.
Calculi ; Humans ; Lithotripsy* ; Retreatment ; Risk Factors ; Shock* ; Ureter* ; Ureteral Calculi* ; Ureteral Obstruction

Ureteroscopy has been used widely to remove ureteral calculi, especially distal ureter stones. Also extracorporeal shock wave lithotripsy (ESWL) has widened its applicability to ureter stones including distal ureter stones. In this study we tried to evaluate the exact role of ureteroscopic manipulation to get rid of ureter stones in the era of ESWL. Success rates and complications of 111 ureteroscopic stone removal procedures performed from December 1986 to May 1995 and those of another 369 patients managed with ESWL from May 1989 to May 1995 were analyzed. Success was defined as complete removal of the stones or residual stones less than 2 mm, immediate postoperatively in ureteroscopic manipulation and 2 weeks after ESWL. The success rate of the ureteroscopic manipulation was 38.9% (7/18), 46.2% (6/13) and 67.5% (54/80) in upper, middle and lower ureter stones, respectively. According to the size of the stone, success rate was 72.4% (21/29), 63.5% (40/63) and 14.3% (9/63) when it was less than 5 mm, 6 to 10 mm and larger than 10 mm. So the overall immediate postoperative success rate of ureteroscopic stone removal was 60.4%, and in another 8.9% of the patients the residual fragmented stones were expelled spontaneously in one month after the procedure. Complications were found in 9.9% of the procedures, including 5 mucosal avulsions and 2 ureteral strictures Success rate of the single session of ESWL was 64% without any differences regardless of the location of the stones in ureter, and it increased up to 88% when another 2 more sessions were tried. Success rate of the single session of ESWL according to the size of the stone was 91.7% (22/24), 67.9% (144/215) and 53.89S (70/130) in stones less than 5 mm, 6 to 10 mm and more than 10 mm, respectively. Complications were found in 3.4% of the patients, including 1.7% of steinstrasse and 1.4% of severe nausea and vomiting. From these observations we can conclude that it seems to be mandatory to renovate the indications of the ureteroscopic stone removal procedures in the era of ESWL.
Constriction, Pathologic ; Humans ; Lithotripsy ; Nausea ; Shock ; Ureter* ; Ureteral Calculi* ; Ureteroscopy ; Vomiting