RESULTS WITH 7.5F VERSUS 10F RIGID URETEROSCOPES IN TREATMENT OF URETERAL CALCULI OZGUR YAYCIOGLU, SEZGIN GUVEL, FERHAT KILINC, TULGA EGILMEZ, AND HAKAN OZKARDES ABSTRACT Objectives. To compare the success and complication rates in the treatment of ureteral stones with a 7.5F versus a 10F ureteroscope. Methods. A total of 100 patients who were scheduled for ureteroscopy to treat ureteral calculi between December 2000 and December 2002 were randomly assigned to procedures with a 7.5F (group 1; n = 50) or 10F (group 2; n = 50) ureteroscope. The group results were compared. Results. Group 1 had 36 distal, 9 middle, and 5 proximal ureteral stones. Group 2 had 37 distal, 6 middle, and 7 proximal ureteral stones. No statistically significant differences were noted between the two groups with respect to the mean stone size or operation time (P = 0.175 and P = 0.636, respectively). Pneumatic lithotripsy was used in 62% and 50% of the procedures in group 1 and 2, respectively, and stones or fragments were retrieved with basket catheters in 92% and 76% of the group procedures, respectively. The difference between the group rates for successful basket catheter extraction was statistically significant (P = 0.029). Of the patients in group 1 and 2, 84% and 80%, respectively, were stone free after a single procedure (P = 0.603). The corresponding failure rates in the two groups were 6% and 12% (P = 0.295), and the corresponding early and late complication rates in the two groups were 6% and 4% (P = 0.646). None of the patients in group 1 developed late complications. One individual (2%) in group 2 developed ureteral stenosis during long-term follow-up (P = 0.315). Conclusions. The success and failure rates revealed better outcomes for treatment of ureteral calculi with a 7.5F ureteroscope, but the differences were not statistically significant. The complication rates were similar between the two groups. Basket catheters were used more frequently with the 7.5F scope, and the rates of in situ lithotripsy and postoperative ureteral stent placement were also greater in patients treated with this instrument. UROLOGY 64: 643–647, 2004. © 2004 Elsevier Inc. T echnological advances and more sophisticated equipment have led to greater success and low morbidity in ureteroscopic treatment of ureteral stones. The development of small-caliber rigid ure- teroscopes has been important in this regard. The diameters of modern rigid ureteroscopes range from 6.9F to 10.5F. These instruments have in- creased the success and safety of ureteroscopic stone treatment and have even made it possible to treat complicated cases, such as impacted stones and stones in pediatric patients, safely. 1–3 How- ever, to our knowledge, no study has yet investi- gated which scope calibers within the range of modern rigid instruments available yield better re- sults when treating ureteral stones. We performed a randomized trial to compare the success and complication rates in the treatment of ureteral stones with a 7.5F versus 10F rigid ureteroscope. MATERIAL AND METHODS A total of 100 patients who were scheduled for uretero- scopic treatment of ureteral calculi between December 2000 and December 2002 were included in the study. All partici- pants gave informed consent. The exclusion criteria were pregnancy, coagulation disorders, active urinary tract infec- tion, ipsilateral ureteral stricture, previous ureteral reimplan- tation surgery, and previous ureteral stent placement. All the procedures were performed by one of a team of four urologists. Patients were randomly assigned to be treated with one of two semirigid ureteroscopes, either 7.5F (group 1; n = 50) or 10F (group 2; n = 50). Balloon dilation of the ureteral orifice was not performed in any of the cases, and placement of a ureteral From the Department of Urology, Baskent University Faculty of Medicine, Ankara; and Department of Urology, Baskent Univer- sity Adana Teaching and Medical Research Center, Ankara, Tur- key Reprint requests: Ozgur Yaycioglu, M.D., Department of Urol- ogy, Baskent University Adana Clinic and Research Center, Dadaloglu Mah. 39 Sok. No: 6, Yuregir, Adana 01250, Turkey Submitted: March 15, 2004, accepted (with revisions): May 11, 2004 ADULT UROLOGY © 2004 ELSEVIER INC. 0090-4295/04/$30.00 ALL RIGHTS RESERVED doi:10.1016/j.urology.2004.05.050 643