Irrigant Flow and Intrarenal Pressure During Flexible Ureteroscopy: The Effect of Different Access Sheaths, Working Channel Instruments, and Hydrostatic Pressure

Abstract

Increased access sheath diameter does not improve flow when the working channel of a flexible ureteroscope is occupied. Our proposed configuration of a ureteral access catheter placed inside or alongside the access sheath provides by far the highest flow rates without a rise in the intrarenal pressure.