Use of a working channel catheter during flexible ureteroscopic laser lithotripsy

Purpose: We describe a technique which protects the working channel of the flexible ureteroscope from damage caused by the laser fiber during laser lithotripsy. Materials and Methods: A 2Fr catheter is placed into the working channel of the flexible ureteroscope. A 200 mu. laser fiber is then advanced through the lumen of the catheter and laser lithotripsy is subsequently performed. Results: The catheter provides additional protection to the working channel sheath during passage and firing of the laser fiber. Deflection of the ureteroscope is not affected with the catheter in place. Movement of the laser fiber is augmented by the catheter when compared to movement of the fiber in the working channel alone. Irrigant flow is diminished with the catheter. Conclusions: The catheter does not appear to hinder performance of the flexible ureteroscope during laser lithotripsy. A catheter also offers additional protection to the working channel sheath, thereby potentially increasing the durability and working life of the flexible ureteroscope.