Abstract
To examine laser fiber passage capabilities through flexible ureterorenoscopes (fURSs) and to measure deflections and flow characteristics.
For this in vitro study, eight fURSs were examined (Olympus(A (R)) URF-P6, URF-P6, URF-V, URF-V2; Storz(A (R)) Xc and Flex-X2; Richard Wolf(A (R)) Cobra Vision; and Lithovue). Four laser fibers standard 200- and 273-mu m (uncleaved and cleaved), sheath-coated and ball-tip fibers were attempted to pass through each fURS while deflected at 120A degrees, 180A degrees, maximum deflection, and maximum deflection with reduced 9-mm radius. Measurements included maximal (up/down) deflections and irrigation flow rates achieved with each fiber.
Wolf Cobra Vision demonstrated minimal loss of deflections with mean differences of -2A degrees/0A degrees (p > 0.05) when loaded with the 200-mu m fiber. The 273-mu m fiber provoked utmost deflections that decline when loaded in Olympus URF-P5: mean differences of -52A degrees/-35A degrees (p < 0.001 for upward deflection). Of overall deflections, sheath-coated fiber induced least insult (p > 0.05), while standard 273-mu m fiber incited maximum degradation (p < 0.00001). With few exceptions, sheath-coated and ball-tip fibers passed through all maximally deflected scopes. Uncleaved 200- and 273-mu m fibers failed to pass through most maximally deflected fURS. However, cleaving their ends allowed 200- and 273-mu m fiber to pass through all angles of deflections expect in the Olympus URF-P5 and Olympus URF-P5 and URF-V, respectively. The irrigation through all fURSs was significantly impaired (p < 0.00001).
fURS deflection was least affected by sheath-coated fibers and most affected by the 273-mu m fiber. Uncleaved 200- and 273-mu m fibers showed least passage capabilities; while removing the ends, the fibers greatly facilitated their passage capabilities as much as the other fibers tested.