TAIPEI, TAIWAN (UroToday.com) - Introduction and Objectives: Holmium laser fiber passage can damage the working channel of a ureteroscope. A recently released ball-tip laser fiber (TracTip - Boston Scientific) is designed to reduce scope trauma. We compared ureteroscope deflection and insertion forces of this ball-tip to a standard laser fiber.
Methods: Ureteroscope deflection was measured using a 200 micron ball-tip (BT) and standard fiber (SF) (Flexiva - Boston Scientific) in three flexible ureteroscopes (URF-P5,URF-P6, URFV - Olympus). Deflection angle was measured using AutoCAD software. Fiber insertion force was measured in a ureteroscope sheath model positioned in a 270 degree curve. The BT and SF fibers were advanced using a stage controller and a strain gauge measured force. ANOVA test was used to compare multiple groups and t-test with Bonferroni correction was used for intergroup comparison.
Results: Both fibers caused equivalent reduction (10–30_) in ureteroscope deflection without statistical difference. Four virgin fibers and ureteroscope sheaths were used to test insertion force of each fiber. Maximum and mean insertion force for the SF was 998 – 394mN and 603– 163mN, respectively. The BT insertion forces were significantly less, at 304 – 31mN maximum (p = 0.04) and 213 – 31mN mean (p= 0.03). One SF fiber caused significant damage to the sheath and could not be advanced completely.
Conclusions: The ball-tip fiber has markedly reduced insertion force in a deflected ureteroscope without compromising maneuverability compared to a standard laser fiber. Minimal investment in the ball-tip fiber may result in cost savings by increasing ureteroscope longevity.
Source of Funding: Boston Scientific
|View an interview with Andreas Neisius, one of the authors of this study.|
Presented by Richard Shin,1 Fernando Cabrera,1 Zachariah Goldsmith,1 Nicholas Kuntz,1 Ramy Youssef,1, 2 Adam Kaplan,1 Andreas Neisius,1, 3 Charles Scales,1, 4 Michael Ferrandino,1 Pei Zhong,1, 5 Glenn Preminger,1 and Michael Lipkin1 at the 32nd World Congress of Endourology & SWL - September 3 - 7, 2014 - Taipei, Taiwan
1Division of Urologic Surgery, Duke University, USA
2Department of Urologic Surgery, University of California, Irvine, USA
3Department of Urology, University Medical Center Mainz, Germany
4Duke Clinical Research Institute, Duke University, USA
5Department of Mechanical Engineering and Materials Science, Duke University, USA