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Ureteroscopic management with laser lithotripsy of renal pelvic stones.

BACKGROUND AND PURPOSE
The development of semirigid and flexible ureteroscopes has permitted easier access to calculi throughout the urinary tract. We compared the use of semirigid and flexible ureteroscopy for the management of shockwave lithotripsy-refractory, isolated renal pelvic calculi by evaluating stone-free rates, operating room times, and associated complications.


PATIENTS AND METHODS
Ureteroscopic stone treatment was attempted in 47 patients with isolated renal pelvic stones between November 2008 and December 2010. The procedures were performed under general anesthesia. Semirigid ureteroscopy was routinely performed in all patients. If the stones were accessible in the renal pelvis with the semirigid ureteroscope (S-URS), they were then treated with the holmium:yttrium-aluminum-garnet (Ho:YAG) laser through S-URS under direct vision. If the stones were not accessible, flexible ureteroscopy was then performed. Preoperative, operative, and postoperative data were retrospectively analyzed.


RESULTS
In 25 of 47 patients, renal pelvic stones were accessible with S-URS, and the stones were fragmented with the Ho:YAG laser using S-URS. In the remaining 22 patients, the stones were accessed with the flexible ureteroscope (F-URS), and the fragmentation of stones was performed with the Ho:YAG laser using the F-URS. There were no significant differences in age, body mass index, grade of hydronephrosis, mean stone size, and stone laterality among the two groups. The mean operative times were 71.90 ± 17.90 minutes in the S-URS group and 93.41 ± 18.56 minutes in the F-URS group (P=0.001). The stone-free rates at postoperative day 1 and at the 1 month follow-up were 72% and 76% in the S-URS group and 81.8% and 86.4% in the F-URS group, respectively (P=0.861 and P=0.368). We found no significant differences among groups with regard to stone-free rates, complication rates, and hospital lengths of stay.


CONCLUSIONS
Although it is well known that flexible ureteroscopy permits a detailed caliceal examination and therapeutic interventions, semirigid ureteroscopy is also often another sufficient means of reaching the renal pelvis in selected patients.