How Effective Is Ureteroscopic Irrigation at Evacuating Stone Dust?

Ureteroscopic laser lithotripsy results in the formation of small and numerous stone fragments. These have the potential to act as a nidus for stone recurrence, and the effectiveness of irrigation via the ureteroscope at clearing them is not well understood. Using an in vitro quartz-based model, fragments of known sizes from <63 µm to 2mm are irrigated at rates of 15 mL/min, 30 mL/min and 120 mL/min. Clinically achievable rates of 15-30 mL/min are unable to wash out larger particles >500 µm, and even 120 mL/min irrigation was able to wash out less than half of these larger particles. Complete stone clearance is unlikely to be achievable by intraoperative irrigation alone and requires additional technologies such as suction.