A Prospective Evaluation of High- and Low-power Holmium Laser Settings for Transurethral Lithotripsy in the Management of Adults with Large Bladder Calculi

Purpose: To prospectively investigate the efficacy and safety of high-power (100 W) vs low-power (20 W) laser settings for transurethral laser lithotripsy in the management large vesical calculi (> 4 cm).

Methods: All patients with vesical calculi > 4 cm in the maximum dimension and scheduled for transurethral holmium laser lithotripsy were invited to participate in the study. Every alternate patient was treated with either the low- or high-power laser settings. We used a continuous irrigation resectoscope with laser bridge or a laser working element (Karl Storz) for laser lithotripsy of bladder stones. We compared the operative time, intra-operative/post-operative complications (up to 1 year), and stone-free rates between the treatment groups using IBM SPSS Statistics 24 software. Comparisons between treatment groups for continuous variables were assessed using the Welch test, while categorical variables were compared with either the Chi-square or Fisher's exact test. A p value < 0.05 was considered statistically significant.

Results: Twenty patients with ten in each cohort were recruited. Preoperative data and mean bladder stone size were comparable in both groups. The duration of surgery was significantly reduced from 70.80 ± 25.28 min in low-power cohort to 40.90 ± 15.01 min in the high-power group (p = 0.005). There were no significant intra-operative complications in either group. All patients were stone-free following the procedure.

Conclusion: High-power laser setting of up to 100 W results in a significant reduction in duration of surgery without any increase in the complication rate for treatment of large bladder stones.