Comparative effectiveness of high-power holmium laser lithotripsy for pediatric patients with kidney and ureteral stones

Abstract

Background: The comparative effectiveness of high-power laser technology for kidney stone surgery in pediatric patients is poorly understood. We compared outcomes for the 120 W Holmium:yttrium-aluminum-garnet (Ho:YAG) laser with MOSES technology to 30 W Ho:YAG laser for pediatric patients undergoing ureteroscopy with laser lithotripsy for kidney and ureteral stones.

Objective: We evaluated the outcomes of the new MOSES laser technology as compared to low-power Ho:YAG lasers commonly used for kidney stone treatment in the pediatric population.

Methods: We performed a retrospective cohort study of 131 consecutive patients aged 1-18 years who underwent ureteroscopy and laser lithotripsy for renal and ureteric calculi at a large freestanding children's hospital between 2013 and 2020. The primary outcome was the efficiency quotient, which incorporates stone clearance, auxiliary procedures, and retreatment rates. Outcomes were compared between groups using Chi-square or Fisher's exact tests and multivariable regression. A sensitivity analysis was performed extending the age limit to ≤21 years.

Results: Outcomes are summarized in the table below. Median age of the cohort was 14 years with 53% of patients being female. MOSES laser had a higher efficiency quotient and was associated with a lower odds of post-operative emergency department visits (OR 0.2, 95% CI 0.0-1.0; p = 0.047). Operative time was similar. In the sensitivity analysis of patients ≤21 years, the statistical significance with fewer emergency department visits was lost and the efficiency quotient was lower.

Discussion: Our results show that stone clearance is similar between the 120 W MOSES and 30 W Ho:YAG lasers. However, there are indications that high-power laser lithotripsy is more efficient due to fewer auxiliary procedures and a reduction in retreatment. In addition, higher power lasers were associated with fewer emergency department visits. The benefits appear to be greater among children ≤18 years. These exploratory findings are important for pediatric patients due to the requirement for general anesthesia for each procedure and their associated impact on children and their caregivers.

Conclusions: High-power laser lithotripsy may be more efficient than lower power laser lithotripsy, which is driven by the fewer auxiliary procedures and reduction in retreatment particularly among youth ≤18 years old.

Keywords: Holmium laser; Pediatric nephrolithiasis; Ureteral stents; Ureteroscopy.