FLEXIBLE URETEROSCOPY - WASHINGTON-UNIVERSITY EXPERIENCE WITH THE 9.3F AND 7.5F FLEXIBLE URETEROSCOPES

Purpose: Recent advances in the design of flexible ureteroscopes have resulted in smaller caliber instruments. We review our experience with the smaller flexible ureteroscopes, and compare the efficacy and effi ciency of the newer 7.5F to the standard 9.3F flexible instruments. Ma terials and Methods: Between January 1991 and 1995, 69 male and 41 fem ale patients (mean age 57 years, range 16 to 91) underwent 116 retrogr ade flexible ureteroscopic procedures for a variety of diagnostic and therapeutic indications. A 9.3F ureteroscope (group 1) was used in 71 patients and a 7.5F instrument (group 2) was used in 39. Results: Pati ents in group 2 received sedation analgesia significantly more often t han those in group 1 (56 versus 35%, p = 0.04). Active dilation of the ureteral orifice was required less often in group 2 (22.5%) than in g roup 1 (58%, p less than or equal to 0.05). The total success rate for stone management, and diagnosis and/or treatment of an upper urinary tract lesion was 98.3 and 100%, respectively, in group 1, and 90 and 1 00%, respectively, in group 2 (p = 0.17). Of the 71 patients in group 1, 17 (24%) were treated on an outpatient basis, compared to 14 of 39 (49%) in group 2 (p = 0.16). No intraoperative or postoperative major complications were encountered in either group. Group 2 required less postoperative analgesia (p = 0.05). No ureteral stricture occurred in either group at an average followup of 9.5 months postoperatively (ran ge 2 to 35). Conclusions: For ureteral and renal pathological conditio ns the 7.5F ureteroscope is as effective as the 9.3F instrument diagno stically and therapeutically. The 7.5F ureteroscope usually can be use d with sedation analgesia. Also, the smaller 7.5F ureteroscope is asso ciated with less need for active ureteral dilation, minimal postoperat ive discomfort and a brief hospital stay.