Pulsed thulium: YAG versus holmium: YAG in a flexible navigable suction access sheath environment: a bench, Ex Vivo, and simulator study

Flexible and navigable suction access sheath (FANS) and pulsed thulium: YAG (p-Tm: YAG) laser represent important advancements in flexible ureteroscopy (fURS). This study evaluated the procedural performance of p-Tm: YAG versus conventional holmium: YAG (Ho: YAG) within a FANS-fURS environment. Die-Stone phantoms and human calcium oxalate monohydrate (COM) stones were ablated using p-Tm: YAG or Ho: YAG lasers (272- \(\:\:μ\:\) m fibers). Fragment size was assessed using a sequential dual-sieve (3.0/0.5 mm) benchtop model. Total ablation ( \(\:{S}ₜ\) ) and dusting ( \(\:{S}d\) ) rates were quantified. To further assess procedure-oriented performance, a urological simulator utilizing 11/13-Fr FANS and a 7.5-Fr ureteroscope was employed to compare operative time, cumulative lasering time (CLT), and operative efficiency between laser platforms. p-Tm: YAG yielded higher \(\:{S}ₜ\) and \(\:{S}d\) across all settings. At the 20 W setting, p-Tm: YAG demonstrated significantly higher \(\:{S}ₜ\) (2.49 ± 0.39 vs. 1.52 ± 0.32 mg/s, p = 0.031) and \(\:{S}d\) (1.97 ± 0.26 vs. 0.98 ± 0.17 mg/s, p = 0.007) compared to Ho: YAG; proportional analysis revealed that p-Tm: YAG achieved a peak dusting fraction (< 0.5 mm) of 79%. For human COM stones, p-Tm: YAG maintained a 2.6-fold higher \(\:{S}ₜ\) and a 3.3-fold higher \(\:{S}d\) , with a dusting proportion of 51.0% compared to 42.7% for Ho: YAG. In the urological simulator, p-Tm: YAG achieved significantly greater procedural efficiency (0.53 ± 0.01 vs. 0.41 ± 0.05 mg/s, p = 0.039). The integration of p-Tm: YAG with FANS technology may improve procedural efficiency by balancing accelerated ablation with high-volume dusting. These findings support further evaluation of p-Tm: YAG in FANS-fURS. Not applicable.