Trapped Flexible Ureteroscope in Ureteral Access Sheath During Retrograde Intrarenal Surgery: An Unexpected Problem

Background: Instrument-related complications occur occasionally with the use of flexible ureteroscopes. In this study, we present a unique problem related to instrument malfunction of flexible ureteroscope during retrograde intrarenal surgery. Case Presentation: A 60-year-old male patient with a 1.2 cm left upper ureteral stone initially underwent semirigid ureteroscopic laser lithotripsy and during the procedure the stone got retropulsed into middle calix of the kidney. Subsequently, a 9.5F (internal diameter) ureteral access sheath was placed and using URF P6R flexible ureteroscope (Olympus) the stone was completely dusted with holmium laser. At the end of the procedure, the operating surgeon was unable to remove the ureteroscope out of the ureteral access sheath as it was getting stuck inside. On careful inspection under fluoroscopy, it was noticed that there was a partial break in the outer surface of the flexible ureteroscope at the level of the junction of the distal flexible part of the ureteroscope with the shaft. Since multiple attempts to retrieve the ureteroscope into the access sheath failed, a decision was made to pull the ureteroscope and ureteral access sheath as a whole over a 0.035″ terumo guidewire. Gentle traction was applied on the entire assembly and the instrument was withdrawn out of ureter over the guidewire under fluoroscopic guidance. A lateral angulation of the distal flexible portion with the shaft of the flexible ureteroscope caused by breakage of the fiber-optic cables led to this problem intraoperatively. Conclusion: Breakage of fiber-optic cables caused by excessive manipulation of flexible ureteroscope during retrograde intrarenal surgery can lead to entrapment of the ureteroscope within the ureteral access sheath. This problem might be solved by gently withdrawing the whole assembly out of the ureter over a guidewire.