Introduction and objective: Recently there has been interest in a dusting technique for lithotripsy during ureteroscopy (URS) utilizing high-frequency and low-pulse energy (HiFr-LoPE) settings. We assessed a 120-W holmium laser that permits high-frequency (>50 Hz) dusting.
Materials and methods: Consecutive URS cases performed by a single surgeon using the P120H (Lumenis, San Jose, CA) were reviewed. Lithotripsy was performed using HiFr-LoPE settings (50-80 Hz/0.2-0.5 J [10-40 W]). Residual fragments (RFs) were determined on postoperative radiography, ultrasonography, or CT. Complications were classified using the Clavien-Dindo grade.
Results: URS was performed on 82 renal units (71 patients). Renal stones constituted the majority (73%), including four partial staghorn stones. Mean stone size and density (HU) were 12.5 mm (SD 8.7; range 5.0-50.0) and 993 (SD 353; range 230-1580), respectively. Ureteral access sheath was used in 15 (21%) patients. Mean total laser energy per case was 5.2 kJ (range 0.1-42.1). Dusting was exclusively performed in 84% of cases. Postoperative stents were placed in 91% (41% string). Zero-fragment and ≤2 mm RF rates were 62.1% and 74.2%, respectively. There were 11 complications (13%) (grade 1 = 5, grade 2 = 6). The emergency department visit rate was 5.6%. There were no hospitalizations or reinterventions.
Conclusions: Refinements in laser technology have expanded methods to ablate urinary stones. Outcomes utilizing a dusting technique demonstrated acceptable RF and complication rates. However, not all stones are amenable to dusting, and further study is needed to define the optimal role of this technique during laser lithotripsy.
Keywords: dusting; holmium laser; lithotripsy; ureteroscopy.