<p class="first" id="d3449832e140">Introduction: A novel single-use flexible ureteroscope
promises the optical characteristics
and maneuverability of a reusable fourth-generation flexible ureteroscope. In this
study, the LithoVue Single-Use Digital flexible ureteroscope was directly compared
with contemporary reusable flexible ureteroscopes, with regard to optics, deflection,
and irrigation flow. Methods: Three flexible ureteroscopes such as the LithoVue (Single
Use; Boston Scientific), Flex-Xc (Karl Storz, Germany), and Cobra (Richard Wolf, Germany)
were assessed in vitro for image resolution, distortion, color representation, grayscale
imaging, field of view, and depth of field. Ureteroscope deflection was tested with
an empty channel followed by placement of a 200 μm laser fiber and a 1.9F wire basket,
a 2.0F nanoelectric pulse lithotripsy (NPL) probe, and a 2.4F NPL probe. Ureteroscope
irrigation flow was measured using normal saline at 100 cm, with an empty channel
followed by a 200 μm laser fiber, a 1.9F wire basket and a 2.0F NPL probe. Results:
The LithoVue showed the largest field of view, with excellent resolution, image distortion,
and depth of field. No substantial difference was demonstrated in color reproducibility
or in the discernment of grayscales between ureteroscopes. The LithoVue maintained
full deflection ability with all instruments in the working channel, although the
Flex-Xc and Cobra ureteroscopes showed loss of deflection ranging from 2° to 27°,
depending on the instrument placed. With an empty channel, the LithoVue showed an
absolute flow rate similar to the Flex-Xc ureteroscope (p = 0.003). It maintained
better flow with instruments in the channel than the Flex-Xc ureteroscope. The Cobra
ureteroscope has a separate 3.3F instrument channel, keeping flow rates the same with
instrument insertion. Conclusion: The LithoVue Single-Use Digital ureteroscope has
comparable optical capabilities, deflection, and flow, making it a viable alternative
to standard reusable fourth-generation flexible digital and fiberoptic ureteroscopes.
</p>