ENDOUROLOGY & LAPAROSCOPY

Clinical utility of dual active deflection flexible ureteroscope during upper tract ureteropyeloscopy
Ankem MK, Lowry PS, Slovick RW, del Rio AM, Nakada SY
From the Division of Urology, Department of Surgery, University of Wisconsin-Madison Medical School, Madison, Wisconsin, USA; Division of Urology, Scott & White Memorial Hospital, Texas A&M University College of Medicine, Temple, Texas, USA
Urology. 2004; 64: 430-4

• Objectives: To evaluate the clinical utility of a dual active deflection ACMI DUR-8 Elite ureteroscope in a referral endourology practice.
• Methods: Retrospective chart review was performed on 54 consecutive patients who underwent flexible ureteroscopy by a single surgeon (S.Y.N.) from February to July 2003. Cases in which standard flexible ureteroscopes alone could complete the procedure, cases in which standard flexible ureteroscopy could not complete the procedure and the DUR-8 Elite ureteroscope did, and cases in which both ureteroscopes failed to complete the procedure were analyzed.
• Results: A total of 54 procedures were performed on 37 patients. Three cases were not analyzed because they were distal ureter procedures. Of the remaining 51 procedures, 6 were removed from analysis because they were second-look procedures. When classified by diagnosis, 27 patients had stones (79.4%), 5 had cancer (14.7%), and 1 had hematuria (2.9%). The global success rate was 91.1%. The average use rate of the DUR-8 was 28.9%, and the success rate using the DUR-8 Elite was 69.2% in those cases in which it was necessary. Of the 13 cases in which the DUR-8 was used, 61.5% were for lower pole pathologic findings. The DUR Elite use and success rate in the lower pole was 57.1% and 75%, respectively. A statistically significant association was found between the diagnosis and procedure location (P = 0.00128).
• Conclusions: Our preliminary data indicate that the dual deflecting DUR-8 Elite ureteroscope may be helpful in cases in which the single deflection flexible instruments fail to access and treat upper urinary tract pathologic findings.
  
  
• Editorial Comment
  The second actively flexible portion of the ureteroscope used by the authors provides an additional 170 degrees of flexion in one direction. The authors clearly demonstrate the utility of this device in their hands. In almost 1/3 of cases, the authors had sub-optimal access with the standard (single actively flexible joint) ureteroscope, and the dual active deflection ACMI DUR-8 Elite ureteroscope was used. About half of the uses of the DUR-8 were for inability to access a calyx (usually lower pole), and about half were because even the 200 micron laser fiber restricted flexion of the standard ureteroscope and the extra flexion of the DUR-8 was needed. Overall, the DUR-8 was successful 2/3 of the time it was used. We have trialed the DUR-8 and other dual active deflection ureteroscopes at our institution but have not yet made a purchase. We have found that failure to access a calyx is uncommon with a good-condition single active deflection ureteroscope and patience. When access is not possible, stones can generally be moved with a nitinol tipless basket (which can get to a stone even when it can barely be seen through the ureteroscope). Moreover, with use of this stone displacement technique, stones in a location that push the limits of flexibility with the 200-micron laser fiber can be moved and addressed more effectively elsewhere. As such, we have less of a use for a dual active deflection ureteroscope than these authors do. That being said, in cases of tumor or large stones, where the lesions cannot be moved, these scopes would undoubtedly be of use. They probably do merit a place in the armamentarium of a busy endourologist.

Dr. J. Stuart Wolf Jr.
Associate Professor of Urology
University of Michigan
Ann Arbor, Michigan, USA