Long Pulse Versus Short Pulse Laser Dusting for Renal Stones

The purpose of this research study is to compare how well two treatments work for removing kidney stones. The two study groups include ureteroscopy with long/short pulse lithotripsy to remove kidney stones. Both of these options are considered standard of care and are used currently in surgery.

This study will compare two types of laser lithotripsy to see the pulse duration to determine which settings are more effective. This is a randomized control trial with subjects randomized to either long pulse or a short pulse group. Those subjects with a single kidney/ureter stone measuring up to 20 mm will be eligible for the study. The procedures will be performed using the standard of care instruments and techniques but the pulse type setting in surgery will be constant. Some Holmium laser devices provide the option to modulate the pulse duration. A longer laser pulse duration (700 μs or 1500 μs) as compared to a traditional pulse duration (300 μs or 350 μs) has been demonstrated in vitro studies to provide effective stone disintegration while reducing laser fiber tip degradation and stone retropulsion. Both the long and the short setting can dust the stone and currently we alternate in each procedure from one setting to the other and it is unclear which setting is more effective. No changes to operative technique will be performed for subjects in the study vs regular patients undergoing the same procedure. All subjects will be seen one week to one month after surgery for stent removal and follow up.

All subjects enrolled in the study will be randomized to either short pulse or long pulse for treatment of their stones. The date of treatment will be decided between the subject and the treating surgeon. All treatments will be performed using the standard of care and will be performed in the same fashion as procedures for patients not enrolled in the study. There is no modification of the techniques used to remove the stones. Post operatively, we plan to discharge all subjects home from the recovery unit. All subjects will be seen one week to one month after surgery for stent removal and a low dose CT of the abdomen and pelvis to assess stone free rates which is standard for all stone patients.

Inclusion Criteria: Kidney/ureter single stone between up to 2 cm Age over 18 years Two kidneys Exclusion Criteria: Solitary Kidney Age under 18 Pregnancy

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