To characterize the pulse characteristics and risk of fiber fracture(ROF) of the pulsed-Thulium:YAG(p-Tm:YAG) Laser , and to compare its ablation volumes(AVs) against Holmium:YAG(Ho:YAG) and Thulium Fiber Lasers(TFL).
p-Tm:YAG(100W-Thulio,DornierMedtech©,Germany) was characterized using single-use 272μm core-diameter-fibers(CDF). p-Tm:YAG characterization included pulse shape, duration and Peak Power (PP) studies. ROF was assessed after 5min continuous laser activation(CLA) at five decreasing fiber bend radii(1, 0.9, 0.75, 0.6, and 0.45cm). p-Tm:YAG, Ho:YAG (120W-Cyber-Ho,Quanta®,USA) and TFL (60W-TFLDrive(Coloplast®, Denmark)) AVs were compared using a 20mm linear CLA at 2mm/sec velocity in contact with 20mm cubic hard and soft stone phantoms(HSP and SSP, 15:3 and 15:5 water to powder ratio) fully submerged in saline solution at 0.5J-20Hz or 1J-10Hz. After CLA, phantoms underwent three-dimensional(3D) micro-scanning(computed tomography) and subsequent 3D segmentation to estimate the AVs, using 3DSlicer©. Each experiment was performed in triplicate.
p-Tm:YAG presents a uniform pulse profile in all of the available pre-set modes. Peak Power(PP) ranged from 564 to 2199W depending on pulse mode. No Laser fiber(LF) fracture occurred at any bend radius. p-Tm:YAG achieved similar mean AVs to TFL and Ho:YAG for HSP(8.96±3.1 vs 9.78±1.1 vs 8.8±2.8mm3, p=0.67) but TFL was associated with higher AVs compared to p-Tm:YAG and Ho:YAG(12.86±1.85 vs 10.12±1.89 vs 7.56±2.21mm3, p=0.002) against SSP. AVs for HSP increased with pulse energy for p-Tm:YAG and Ho:YAG and (11.56±1.8 vs 6.36±0.84 mm3 and 11.27±1.98 vs 6.34±0.55mm3,p=0,03 and p=0,02), while AVs for SSP were similar across laser settings for all laser sources. AVs with TFL were similar across laser settings for both phantom types.
p-Tm:YAG combines intermediate Peak Power between Ho:YAG and TFL, a uniform pulse profile, no risk of fiber fracture with increasing deflection and effective ablation rates. Further clinical studies are needed to confirm these in vitro results.
Journal of endourology. 2024 Sep 16 [Epub ahead of print]
Marie Chicaud, Stessy Kutchukian, Mariela Corrales, Laurent Berthe, Catalina Solano, Luigi Candela, Steeve Doizi, Daron Smith, Olivier Traxer, Frédéric Panthier
Sorbonne Universite, GRC n°20, Groupe de Recherche Clinique sur la Lithiase Urinaire, Hôpital Tenon, Sorbonne Université, 75020, Paris, France., Paris, Île-de-France, France., Sorbonne Universite, GRC n°20, Groupe de Recherche Clinique sur la Lithiase Urinaire, Hôpital Tenon, Sorbonne Université, 75020, Paris, France., Paris, Île-de-France, France; ., Arts et Métiers, PIMM, UMR 8006 CNRS-Arts et Métiers ParisTech, 151 bd de l'Hôpital, F-75013 Paris, France, Paris, Île-de-France, France; ., Sorbonne Universite, GRC n°20, Groupe de Recherche Clinique sur la Lithiase Urinaire, Hôpital Tenon, Sorbonne Université, 75020, Paris, France., Paris, Île-de-France, France; ., University College London Hospitals NHS Foundation Trust, Urology, London, London, United Kingdom of Great Britain and Northern Ireland; .