In Vitro Ablation Rates of Ho:YAG, p-Tm:YAG and TFL Lasers

In Vitro Ablation Rates of Ho:YAG, p-Tm:YAG and TFL Lasers | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article In Vitro Ablation Rates of Ho:YAG, p-Tm:YAG and TFL Lasers Alberto Quarà, Alejandra Bravo-Balado, Stefano Moretto, Aideen Madden, and 15 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7160763/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 10 Nov, 2025 Read the published version in World Journal of Urology → Version 1 posted 9 You are reading this latest preprint version Abstract Objective This study compares the ablation rates of three laser systems—Holmium:YAG (Ho:YAG), Thulium Fiber Laser (TFL), and Pulsed Thulium:YAG (p-Tm:YAG)—for renal stone lithotripsy using a standardized robotic setup. Materials and Methods A robotic arm enabled consistent laser application on stone phantoms simulating calcium oxalate monohydrate (hard) and uric acid (soft) stones. Ablation efficiency (mm³/J) was assessed across different laser settings (0.2 J – 50 Hz, 0.5 J – 20 Hz, and 1.0 J – 10 Hz) and fiber diameters (200 and 272 µm). Ablated volumes were quantified via micro-CT and 3D segmentation using 3DSlicer. Statistical analysis evaluated differences in performance. Results TFL demonstrated the highest ablation rates for both hard and soft stones, significantly outperforming Ho:YAG in multiple settings. For hard stones, TFL exhibited greater ablation efficiency than Ho:YAG, particularly at 0.5 J − 20 Hz and 1.0 J − 10 Hz. The p-Tm:YAG laser also outperformed Ho:YAG at 0.5 J − 20 Hz. For soft stones, the difference between TFL and Tm:YAG was statistically significant at lower energy settings (0.20 J − 50 Hz and 0.5 J − 20 Hz). Compared to Ho:YAG, TFL showed significantly higher ablation rates across all tested settings (p < 0.05). The p-Tm:YAG laser showed intermediate performance, with higher efficiency than Ho:YAG but slightly lower than TFL. Fiber diameter influenced ablation, with 272 µm fibers yielding greater efficiency at lower energy settings (p < 0.05 at 0.20 J − 50 Hz and 0.5 J − 20 Hz for both stone types); this comparison was limited to p-Tm:YAG, as data for the other lasers are already available in the literature. Conclusion TFL achieved the highest in vitro ablation efficiency. However, p-Tm:YAG represents a promising compromise, offering improved performance over Ho:YAG and a balanced profile between fragmentation and dusting capabilities. Laser Lithotripsy Ho:YAG Pulsed Thulium:YAG Laser Thulium Fiber Laser Ablation Kidney Stones Figures Figure 1 Figure 2 Introduction Laser lithotripsy has revolutionized the management of urinary stones, offering minimally invasive solutions with high efficacy and safety. Over the years, Holmium:Yttrium-Aluminum-Garnet (Ho:YAG) has been the gold standard for laser lithotripsy, demonstrating reliability in stone fragmentation and dusting ( 1 – 3 ). However, recent advancements in laser technology have introduced alternative systems, such as the Thulium Fiber Laser (TFL) and the pulsed Thulium:Yttrium-Aluminum-Garnet (p-Tm:YAG) laser, which offer distinct physical properties that may enhance stone ablation efficiency and procedural outcomes ( 4 ). TFL has gained significant attention due to its high repetition rates, lower pulse energy and improved fragmentation efficiency, which allow for more effective pulverization strategies and reduced retropulsion, without the need to increase the frequency for faster ablation ( 5 – 7 ). In contrast, the newly developed p-Tm:YAG laser provides an intermediate profile between Ho:YAG and TFL, with a balanced combination of peak power (PP), pulse duration, and ablation performance ( 8 ). Although these technologies have been individually studied, direct comparisons under standardized conditions remain limited ( 9 ). A direct comparison between TFL and Ho:YAG has been recently conducted using a standardized robotic arm to ensure highly reproducible and controlled experimental conditions. Building on this methodology, the present study expands the comparison by incorporating pulsed Tm:YAG. Notably, two p-Tm:YAG systems are currently available on the market: the Dornier Thulium, for which several in vitro and in vivo studies exist, and the Omniguide Revolt, for which data remain scarce( 10 ). This study aims to provide a comprehensive evaluation of the ablation rates of Ho:YAG, TFL, and p-Tm:YAG lasers for lithotripsy using a controlled and reproducible experimental setup. By analysing their performance across different stone compositions and laser settings, we seek to clarify the advantages and limitations of each laser technology and contribute to the optimisation of laser lithotripsy techniques to improve clinical outcomes. Materials and methods Ho:YAG, TFL, and p-Tm:YAG generators and fibers In this study, we did compared the performance of three different laser sources for medical applications. The first device tested was a 50 W TFL (IPG Photonics®, Russia) with a wavelength of 1940 nm, used a 272µm fibers. The second system was a diode-pumped solid-state (DPSS) p-Tm:YAG RevoLix HTL prototype (OmniGuide, USA) laser with a wavelength of 2013 nm, tested with both 200µm and 272µm fibers. Finally, we evaluated the performance of a 30 W Ho:YAG laser (MH1 Rocamed®, Monaco) with a wavelength of 2120 nm, also coupled with 272 µm fibers. Stone phantoms BegoStones measuring 1cm³ were fabricated following previously described methods( 11 ). To replicate calcium oxalate monohydrate (Hard) and uric acid (Soft) stones, we used a “powder-to-water” ratio of 15:3 for Hard stones and 15:5 for Soft stones. After shaping, the samples underwent a 48-hour drying period at 30°C to reduce heterogeneity. Experimental setup Stone phantoms were fully submerged in saline solution at room temperature and securely fixed within a bench model. To evaluate the performance of the TFL, p-Tm:YAG, and Ho:YAG lasers, we used 272 µm fibers. Additionally, the ablation efficiency of the p-Tm:YAG laser was also assessed using a 200 µm fiber. The laser fiber tip was positioned perpendicularly and kept in direct contact with the stone surface. A custom-designed fiber support was developed to ensure complete stability during laser emission. To minimize the “burnback effect”, we adopted a “one locus-one pulse” approach( 12 ). A six-axis robotic arm (KR6R900, Kuka International ©, Germany) was employed to execute a precisely programmed spiral trajectory. Laser emission and robotic arm movement were synchronized and controlled via computational command. The laser fiber followed an Archimedean Type-4 spiral trajectory for 20 seconds, with a 4 mm radius and a constant 1.2 mm spacing between spiral turns. Regarding laser settings, three different configurations were tested for all laser types: 0.2 J – 50 Hz, 0.5 J – 20 Hz, and 1 J – 10 Hz. While TFL was operated in short pulse mode, the Ho:YAG were set to long pulse mode and the p-Tm:YAG laser was set to 50%. Each test was performed in three times to ensure reproducibility. Following laser emission, the stones were dried according to previously described protocols. Three-dimensional imaging of the artificial stones was conducted using a micro-CT scanner (Quantum FX, Perkin Elmer©), and volumetric analysis was carried out through 3D segmentation using 3DSlicer software (NIH©) [11] [Figures 1 and 2 ]. All volumetric analyses were reviewed by a single operator (A.Q.) to eliminate inter-individual variability. Statistical analysis For the analysis of ablation rates, a two-tailed Student's t-test was performed using IBM SPSS Statistics for Macintosh, Version 29.0.2.0 (IBM Corp., Armonk, NY, 2023). A p-value of less than 0.05 was considered statistically significant. Results The comparison of ablation rates among the Ho:YAG, TFL, and p-Tm:YAG lasers revealed significant differences in performance depending on the laser type, energy settings, and stone composition. For hard stones, the TFL laser consistently demonstrated absolute higher ablation rates than both the p-Tm:YAG and Ho:YAG lasers at all energy settings. Although the difference between TFL and p-Tm:YAG was not statistically significant (p > 0.05), the TFL exhibited significantly greater ablation efficiency than the Ho:YAG laser, particularly at 0.5 J − 20 Hz (27.90 mm3/min ± 8.83 vs 16.84 mm3/min ± 1.17 - p = 0.04) and 1.0 J − 10 Hz (29.53 mm3/min ± 3.66 vs 20.86 mm3/min ± 1.76 - p = 0.01). The p-Tm:YAG laser also outperformed the Ho:YAG laser at 0.5 J − 20 Hz (22.96 mm3/min ± 3.03 vs 16.84 ± 1.17 - p = 0.01), but no significant difference was observed at 1.0 J − 10 Hz (25.02 mm3/min ± 6.42 vs 20.86 mm3/min ± 1.76 - p = 0.17) [Tables 1 – 2 – 3 ]. Table 1 Comparison between TFL and Tm:YAG lasers. Interface Laser settings Ablation rate (mm3/min) p value TFL (mean ± SD) p-Tm:YAG (mean ± SD) Hard Stones 0.20 J – 50 Hz 25.95 (± 7.35) 19.74 (± 1.16) 0.11 0.5 J − 20 Hz 27.90 (± 8.83) 22.96 (± 3.03) 0.21 1.0 J -10 Hz 29.53 (± 3.66) 25.02 (± 6.42) 0.18 Soft Stones 0.20 J – 50 Hz 30.83 (± 3.55) 25.76 (± 0.17) 0.03 0.5 J − 20 Hz 32.65 (± 1.76) 24.95 (± 0.90) 0.00 1.0 J -10 Hz 33.64 (± 5.19) 27.16 (± 8.43) 0.16 Table 2 Comparison between TFL and Ho:YAG lasers. Interface Laser settings Ablation rate (mm3/min) p value TFL (mean ± SD) Ho:YAG (mean ± SD) Hard Stones 0.20 J – 50 Hz 25.95 (± 7.35) NA NA 0.5 J − 20 Hz 27.90 (± 8.83) 16.84 (± 1.17) 0.04 1.0 J -10 Hz 29.53 (± 3.66) 20.86 (± 1.76) 0.01 Soft Stones 0.20 J – 50 Hz 30.83 (± 3.55) NA NA 0.5 J − 20 Hz 32.65 (± 1.76) 16.57 (± 8.38) 0.02 1.0 J -10 Hz 33.64 (± 5.19) 18.57 (± 3.03) 0.00 Table 3 Comparison between Ho:YAG and Tm:YAG lasers. Interface Laser settings Ablation rate (mm3/min) p value p-Tm:YAG (mean ± SD) Ho:YAG (mean ± SD) Hard Stones 0.20 J – 50 Hz 19.74 (± 1.16) NA NA 0.5 J − 20 Hz 22.96 (± 3.03) 16.84 (± 1.17) 0.01 1.0 J -10 Hz 25.02 (± 6.42) 20.86 (± 1.76) 0.17 Soft Stones 0.20 J – 50 Hz 25.76 (± 0.17) NA NA 0.5 J − 20 Hz 24.95 (± 0.90) 16.57 (± 8.38) 0.08 1.0 J -10 Hz 27.16 (± 8.43) 18.57 (± 3.03) 0.08 For soft stones, the TFL laser demonstrated superior ablation rates compared to both the p-Tm:YAG and Ho:YAG lasers. The difference between TFL and Tm:YAG was statistically significant at lower energy settings, with p-values of 0.03 (30.83 mm3/min ± 3.55 vs 25.76 mm3/min ± 0.17) and 0.00 (32.65 mm3/min ± 1.76 vs 24.95 mm3/min ± 0.90) for 0.20 J − 50 Hz and 0.5 J − 20 Hz, respectively. In the comparison between TFL and Ho:YAG, TFL showed significantly higher ablation rates at all tested energy settings (p < 0.05). Additionally, p-Tm:YAG outperformed Ho:YAG for soft stones at 0.5 J − 20 Hz and 1.0 J − 10 Hz, though the differences were not statistically significant (p = 0.08 for both) [Tables 1 – 2 – 3 ]. Finally, the comparison of ablation efficiency between 200 µm and 272 µm fibers using the Tm:YAG laser showed that the 272 µm fiber resulted in significantly higher ablation rates for both hard and soft stones at lower energy settings. Statistically significant differences were observed at 0.20 J − 50 Hz and 0.5 J − 20 Hz for both stone types [Table 4 ]. Table 4 Comparison of 200 µm vs 272 µm fibers in Tm:YAG laser. Interface Laser settings Ablation rate (mm3/min) p value 200um (mean ± SD) 272um (mean ± SD) Hard Stones 0.20 J – 50 Hz 15.93 (± 0.83) 19.74 (± 1.16) 0.00 0.5 J − 20 Hz 17.09 (± 1.58) 22.96 (± 3.03) 0.02 1.0 J -10 Hz 19.30 (± 0.50) 25.02 (± 6.42) 0.10 Soft Stones 0.20 J – 50 Hz 20.65 (± 1.92) 25.76 (± 0.17) 0.01 0.5 J − 20 Hz 22.39 (± 0.84) 24.95 (± 0.90) 0.01 1.0 J -10 Hz 22.72 (± 3.56) 27.16 (± 8.43) 0.22 Discussion This study provides a comprehensive comparison of TFL, p-Tm:YAG, and Ho:YAG lasers for kidney stone ablation using a standardized robotic arm. Notably, this is the first comparative study to incorporate a fully automated mechanical robotic arm, ensuring precise and reproducible conditions for laser evaluation. Our results demonstrate that p-Tm:YAG achieves excellent ablation efficiency across the two stone-phantom compositions designed to mimic calcium oxalate monohydrate (COM) and uric-acid (UA) stones. These findings are in line with earlier work showing that p-Tm:YAG effectively ablates both COM and UA stones without statistically significant differences, confirming its robust performance irrespective of stone composition or laser settings( 13 ). Importantly, we acknowledge that the definition and fabrication of our phantoms are grounded in their acoustical—rather than optical—characteristics, following the approach described by Esch et al., which matches the elastic and fracture properties that dominate fragmentation dynamics( 11 ). Early clinical experiences have demonstrated the effectiveness and safety of Dornier p-Tm:YAG in flexible ureteroscopic lithotripsy, yielding comparable stone-free rates to TFL (75% vs. 77%, p = 0.8), albeit with a slightly lower dusting efficiency ( 14 , 15 ). Recent systematic reviews confirm that p-Tm:YAG is a viable alternative to Ho:YAG and TFL, offering a balance between these technologies for endoscopic lithotripsy applications. Additionally, purely p-Tm:YAG lasers have shown promising safety and efficacy in RIRS and PCNL, with their higher PP compared to TFL enabling efficient stone disintegration and effective pulverization( 16 , 17 ). Our findings indicate that for hard stones, TFL consistently demonstrated higher ablation rates than both Tm:YAG and Ho:YAG, regardless of energy settings. The difference between TFL and Tm:YAG was not statistically significant, however, TFL significantly outperformed Ho:YAG at 0.5 J − 20 Hz and 1.0 J − 10 Hz. While both p-Tm:YAG and TFL outperformed Ho:YAG, a key distinction emerged in their dusting efficiency. A recent study shows that p-Tm:YAG produced lower zero fragmentation rates (ZFR) than TFL (39% vs. 64%, p = 0.008), suggesting a relatively low ability to generate particulate matter( 15 ). This implies that TFL remains superior for dusting strategies, whereas p-Tm:YAG maintains a balanced profile between fragmentation and dusting ( 15 ). Notably, Tm:YAG also exhibited higher efficiency than Ho:YAG at 0.5 J − 20 Hz (p = 0.01). These results suggest that while TFL is the most effective option for hard stone ablation, Tm:YAG still provides significant advantages over Ho:YAG, particularly at certain energy settings. For soft stones, TFL demonstrated superior ablation rates compared to both Tm:YAG and Ho:YAG, with statistically significant differences at lower energy settings. Additionally, the comparison between TFL and Ho:YAG confirmed TFL’s superior performance, as it achieved significantly higher ablation rates across all tested energy settings (p < 0.05). Although Tm:YAG outperformed Ho:YAG at 0.5 J − 20 Hz and 1.0 J − 10 Hz, these differences were not statistically significant (p = 0.08 for both). These findings align with recent literature. A recent in vitro study by Sierra del Rio et al., reported that both p-Tm:YAG and TFL exhibited superior performance in laser lithotripsy compared to Ho:YAG, demonstrating higher efficiency and ablation speed. Moreover, thermal damage was not linked to a specific laser type but was instead associated with increasing power settings( 8 ). Additionally, a recent study by Petzold et al. showed that longer pulse durations significantly enhance Tm:YAG’s ablation rates compared to Ho:YAG, further supporting its efficacy( 18 ). From a technical perspective, the p-Tm:YAG laser represents an intermediate option between Ho:YAG and TFL, balancing key properties such as PP, a uniform pulse profile, and reduced risk of fiber fracture in vitro. The lower PP and more uniform pulse profile of both TFL and p-Tm:YAG play a major role in reducing retropulsion, allowing for prolonged contact between the fiber tip and the stone. This extended interaction enhances fragmentation efficiency, positioning both p-Tm:YAG and TFL as superior to Ho:YAG in terms of ablation performance ( 19 – 22 ). Finally, our study demonstrated that using a 272 µm fiber with the Tm:YAG laser resulted in significantly higher ablation rates than the 200 µm fiber for both hard and soft stones at lower energy settings, with statistically significant differences observed at 0.20 J − 50 Hz and 0.5 J − 20 Hz. These findings are consistent with those reported by Panthier et al. (2020) for TFL and Ho:YAG, reinforcing the importance of fiber diameter in optimizing laser lithotripsy efficiency ( 10 ). In clinical practice, however, smaller fibers are commonly used with TFL, typically 150 µm, differing from the larger diameters often employed with other lasers. Despite its novelty, the current study has several limitations. BegoStones phantoms are widely used in vitro due to their consistency and ease of handling, however, they do not fully replicate the optical absorption and thermal properties of human stones. Consequently, laser settings effective on BegoStones phantoms may not yield identical results in clinical practice due to differences in absorption, fragmentation patterns, and thermal interactions. Nonetheless, their use provides a controlled and reproducible model for evaluating laser performance. It is also important to underline that our model does not allow for a detailed analysis of fragment size or composition, since only fine dust is generated with stone phantoms. As a result, we were unable to investigate the fragmentation pattern or potential for clinically relevant fragments, which is a crucial outcome when treating real human stones. In vivo studies could provide valuable insights into this aspect, as has already been shown for Thulium Fiber Laser ( 13 ). Moreover, although this study focuses on ablation rate as a primary endpoint, it should be noted that in clinical practice the ultimate success criteria are stone-free rates (SFR) and the need for retreatment, which depend not only on ablation efficiency but also on fragmentation characteristics, retropulsion, and the ability to clear residual fragments. From a mechanistic standpoint, while it is generally accepted that stone ablation occurs through laser-induced energy absorption by the stone surface, the dominant underlying mechanism, whether photothermal or photomechanical, remains a matter of ongoing investigation. It is currently hypothesized that thermal effects play a primary role, particularly with TFL and p-Tm:YAG lasers due to their lower peak power and longer pulse duration, which promote gradual energy deposition and heat-driven disintegration. Some studies have contributed significantly to this understanding and support the predominance of thermal mechanisms, although the interplay with photomechanical forces cannot be excluded ( 23 ). Conclusion TFL confirmed to be the most effective laser for in vitro lithotripsy, while p-Tm:YAG provides a promising middle-ground solution. Indeed, p-Tm:YAG represents a viable alternative to Ho:YAG, offering a balance between fragmentation and dusting efficiency. Declarations Conflict of Interest Statement: Olivier Traxer has declared as consultant for Karl Storz, Coloplast, IPG photonics, Ambu, Quanta System and Rocamed. Frédéric Panthier has declared as consultant for Dornier. All other authors have no conflict of interest. Source of funding none. Author Contribution Quarà - Conceptualization, Methodology, Data curation, Writing-Original draft preparation; Bravo-Balado - Conceptualization, Methodology, Data curation; Moretto - Conceptualization, Methodology, Data curation; Madden - Data curation; Zorzi - Data curation; Jannello - Writing - Review & Editing; Kutchukian - Writing - Review & Editing, Cabrera - Methodology, Data curation; Corrales - Methodology, Data curation; Chicaud - Methodology, Data curation; Gradilone - Data curation, Candela - Data curation, Writing - Review & Editing, Gorny - Methodology, Data curation; Coste - Methodology, Data curation; Berthe L. - Methodology, Data curation; Doizi - Writing - Review & Editing, Supervision; Panthier - Writing - Review & Editing, Supervision; Fiori - Writing - Review & Editing, Supervision; Traxer - Writing - Review & Editing, Supervision Acknowledgement None. References Kronenberg P, Cerrato C, Juliebø-Jones P, Herrmann T, Tokas T, Somani BK. 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Cite Share Download PDF Status: Published Journal Publication published 10 Nov, 2025 Read the published version in World Journal of Urology → Version 1 posted Editorial decision: Revision requested 21 Aug, 2025 Reviews received at journal 15 Aug, 2025 Reviewers agreed at journal 13 Aug, 2025 Reviews received at journal 13 Aug, 2025 Reviewers agreed at journal 13 Aug, 2025 Reviewers invited by journal 12 Aug, 2025 Editor assigned by journal 19 Jul, 2025 Submission checks completed at journal 19 Jul, 2025 First submitted to journal 18 Jul, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Quarà","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA9ElEQVRIiWNgGAWjYBADGQMwVQHEzMwNRGnhAWphbGA4A9LCSIoWxjYQm4AWvhvJzz78YLDjMWfvff7g47zaaP52oJYfFdtwapG8kWY8s4chmcey57hh48xtx3NnHAba1nPmNk4tBjcSjBl4GJh5DG6kMTbzbjuW2wDUwszYhk9L+mfGPwz1PAb3nwG1zDmWO5+wlhxjZh6Gw0Bb2IBaGmpyNxDSInnmTTGzjMFxoF/SGGfOOHYgdyNQy0F8fuE7nr6Z8U1FtZw5+zGGDx9q6nLnnT988MGPCtxaGA6AnQfnHkYI4teCAHV4FY+CUTAKRsHIBADSZll7uYM0SwAAAABJRU5ErkJggg==","orcid":"","institution":"Hôpital Tenon, Sorbonne Université","correspondingAuthor":true,"prefix":"","firstName":"Alberto","middleName":"","lastName":"Quarà","suffix":""},{"id":501112954,"identity":"55eac181-69ff-4e13-bae8-94fd1153b0a9","order_by":1,"name":"Alejandra Bravo-Balado","email":"","orcid":"","institution":"Hôpital Tenon, Sorbonne Université","correspondingAuthor":false,"prefix":"","firstName":"Alejandra","middleName":"","lastName":"Bravo-Balado","suffix":""},{"id":501112955,"identity":"1b8df9cd-99ff-434a-b317-3e840025addf","order_by":2,"name":"Stefano Moretto","email":"","orcid":"","institution":"Hôpital Tenon, Sorbonne Université","correspondingAuthor":false,"prefix":"","firstName":"Stefano","middleName":"","lastName":"Moretto","suffix":""},{"id":501112956,"identity":"c4f1a9cb-655e-4bde-a62f-dd191b587876","order_by":3,"name":"Aideen Madden","email":"","orcid":"","institution":"Hôpital Tenon, Sorbonne Université","correspondingAuthor":false,"prefix":"","firstName":"Aideen","middleName":"","lastName":"Madden","suffix":""},{"id":501112957,"identity":"5b716d70-8047-44a2-b1c5-1ab33590280e","order_by":4,"name":"Federico Zorzi","email":"","orcid":"","institution":"Hôpital Tenon, Sorbonne Université","correspondingAuthor":false,"prefix":"","firstName":"Federico","middleName":"","lastName":"Zorzi","suffix":""},{"id":501112958,"identity":"191a0bf0-0e24-489b-8f54-32692471b450","order_by":5,"name":"Letizia Maria Ippolita Jannello","email":"","orcid":"","institution":"Hôpital Tenon, Sorbonne Université","correspondingAuthor":false,"prefix":"","firstName":"Letizia","middleName":"Maria Ippolita","lastName":"Jannello","suffix":""},{"id":501112959,"identity":"3a380298-5c17-4318-aaa5-f92c9da4464b","order_by":6,"name":"Stessy Kutchukian","email":"","orcid":"","institution":"Hôpital Tenon, Sorbonne Université","correspondingAuthor":false,"prefix":"","firstName":"Stessy","middleName":"","lastName":"Kutchukian","suffix":""},{"id":501112960,"identity":"7e017f07-72ba-453a-b8d1-fc437022be2e","order_by":7,"name":"Johan Cabrera","email":"","orcid":"","institution":"Hôpital Tenon, Sorbonne Université","correspondingAuthor":false,"prefix":"","firstName":"Johan","middleName":"","lastName":"Cabrera","suffix":""},{"id":501112962,"identity":"b69e8b98-7510-406e-b5f5-548b3f8facaa","order_by":8,"name":"Mariela Corrales","email":"","orcid":"","institution":"Hôpital Tenon, Sorbonne Université","correspondingAuthor":false,"prefix":"","firstName":"Mariela","middleName":"","lastName":"Corrales","suffix":""},{"id":501112964,"identity":"5da2a534-9981-4781-af25-10b35d0bd21e","order_by":9,"name":"Marie Chicaud","email":"","orcid":"","institution":"Hôpital Tenon, Sorbonne Université","correspondingAuthor":false,"prefix":"","firstName":"Marie","middleName":"","lastName":"Chicaud","suffix":""},{"id":501112965,"identity":"0ab22085-ddeb-4bb4-848f-3b592468131c","order_by":10,"name":"Ugo Gradilone","email":"","orcid":"","institution":"Hôpital Tenon, Sorbonne Université","correspondingAuthor":false,"prefix":"","firstName":"Ugo","middleName":"","lastName":"Gradilone","suffix":""},{"id":501112966,"identity":"c249fe99-04fc-49da-b2b3-7d882289ee1b","order_by":11,"name":"Luigi Candela","email":"","orcid":"","institution":"Hôpital Tenon, Sorbonne Université","correspondingAuthor":false,"prefix":"","firstName":"Luigi","middleName":"","lastName":"Candela","suffix":""},{"id":501112967,"identity":"d3938934-f8b5-496c-adf0-8aa8cf34f2c2","order_by":12,"name":"Cyril Gorny","email":"","orcid":"","institution":"PIMM, UMR 8006 CNRS-Arts et Métiers ParisTech","correspondingAuthor":false,"prefix":"","firstName":"Cyril","middleName":"","lastName":"Gorny","suffix":""},{"id":501112968,"identity":"da28b21d-68a5-40de-9a02-c6f03b152a04","order_by":13,"name":"Frederic Coste","email":"","orcid":"","institution":"PIMM, UMR 8006 CNRS-Arts et Métiers ParisTech","correspondingAuthor":false,"prefix":"","firstName":"Frederic","middleName":"","lastName":"Coste","suffix":""},{"id":501112969,"identity":"b3487068-fa87-4dfc-a9e3-0d92f154eab3","order_by":14,"name":"Laurent Berthe","email":"","orcid":"","institution":"PIMM, UMR 8006 CNRS-Arts et Métiers ParisTech","correspondingAuthor":false,"prefix":"","firstName":"Laurent","middleName":"","lastName":"Berthe","suffix":""},{"id":501112970,"identity":"11e47842-f486-4840-b1d1-1a0bd3ba0c71","order_by":15,"name":"Steeve Doizi","email":"","orcid":"","institution":"Hôpital Tenon, Sorbonne Université","correspondingAuthor":false,"prefix":"","firstName":"Steeve","middleName":"","lastName":"Doizi","suffix":""},{"id":501112971,"identity":"8c84f970-e9c6-4a8d-b0ca-ad88b770be7d","order_by":16,"name":"Frederic Panthier","email":"","orcid":"","institution":"Hôpital Tenon, Sorbonne Université","correspondingAuthor":false,"prefix":"","firstName":"Frederic","middleName":"","lastName":"Panthier","suffix":""},{"id":501112972,"identity":"d16de522-d145-4a52-89e1-2d785f6dedc4","order_by":17,"name":"Cristian Fiori","email":"","orcid":"","institution":"University of Turin, San Luigi Gonzaga Hospital","correspondingAuthor":false,"prefix":"","firstName":"Cristian","middleName":"","lastName":"Fiori","suffix":""},{"id":501112973,"identity":"b19d8c6c-5b86-4c47-8eac-bf71a81451a0","order_by":18,"name":"Olivier Traxer","email":"","orcid":"","institution":"Hôpital Tenon, Sorbonne Université","correspondingAuthor":false,"prefix":"","firstName":"Olivier","middleName":"","lastName":"Traxer","suffix":""}],"badges":[],"createdAt":"2025-07-18 22:08:08","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7160763/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7160763/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00345-025-06001-9","type":"published","date":"2025-11-10T15:56:53+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":89470999,"identity":"90faef85-a0f4-410a-9819-e7818b45c6cc","added_by":"auto","created_at":"2025-08-20 09:25:21","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1477183,"visible":true,"origin":"","legend":"\u003cp\u003e3DSlicer segmentation method to evaluate ablation volumes: stone segmentation from CT by selecting the region of interest (ROI)\u003c/p\u003e","description":"","filename":"Figure1SpiralLaser.png","url":"https://assets-eu.researchsquare.com/files/rs-7160763/v1/23b15411fea46c0819f07bac.png"},{"id":89471428,"identity":"9140951b-7673-4b53-abe5-abb89ef55cec","added_by":"auto","created_at":"2025-08-20 09:33:21","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":1040851,"visible":true,"origin":"","legend":"\u003cp\u003e3DSlicer segmentation method for evaluating ablation volumes: segmentation of the spiral crater area and compilation of both to obtain the ablation volume.\u003c/p\u003e","description":"","filename":"Figure2SpiralLaser.png","url":"https://assets-eu.researchsquare.com/files/rs-7160763/v1/da14abf3c5b83bce67990eb8.png"},{"id":96104914,"identity":"0521063c-4d6d-447b-a0c0-4954c770f3c1","added_by":"auto","created_at":"2025-11-17 15:59:25","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3893618,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7160763/v1/0b2485fb-46ac-4177-80e3-be4c4effa57d.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eIn Vitro Ablation Rates of Ho:YAG, p-Tm:YAG and TFL Lasers\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eLaser lithotripsy has revolutionized the management of urinary stones, offering minimally invasive solutions with high efficacy and safety. Over the years, Holmium:Yttrium-Aluminum-Garnet (Ho:YAG) has been the gold standard for laser lithotripsy, demonstrating reliability in stone fragmentation and dusting (\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eHowever, recent advancements in laser technology have introduced alternative systems, such as the Thulium Fiber Laser (TFL) and the pulsed Thulium:Yttrium-Aluminum-Garnet (p-Tm:YAG) laser, which offer distinct physical properties that may enhance stone ablation efficiency and procedural outcomes (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eTFL has gained significant attention due to its high repetition rates, lower pulse energy and improved fragmentation efficiency, which allow for more effective pulverization strategies and reduced retropulsion, without the need to increase the frequency for faster ablation (\u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e). In contrast, the newly developed p-Tm:YAG laser provides an intermediate profile between Ho:YAG and TFL, with a balanced combination of peak power (PP), pulse duration, and ablation performance (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). Although these technologies have been individually studied, direct comparisons under standardized conditions remain limited (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eA direct comparison between TFL and Ho:YAG has been recently conducted using a standardized robotic arm to ensure highly reproducible and controlled experimental conditions. Building on this methodology, the present study expands the comparison by incorporating pulsed Tm:YAG. Notably, two p-Tm:YAG systems are currently available on the market: the Dornier Thulium, for which several in vitro and in vivo studies exist, and the Omniguide Revolt, for which data remain scarce(\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThis study aims to provide a comprehensive evaluation of the ablation rates of Ho:YAG, TFL, and p-Tm:YAG lasers for lithotripsy using a controlled and reproducible experimental setup. By analysing their performance across different stone compositions and laser settings, we seek to clarify the advantages and limitations of each laser technology and contribute to the optimisation of laser lithotripsy techniques to improve clinical outcomes.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cp\u003e\u003cb\u003eHo:YAG, TFL, and p-Tm:YAG generators and fibers\u003c/b\u003e\u003c/p\u003e\u003cp\u003eIn this study, we did compared the performance of three different laser sources for medical applications. The first device tested was a 50 W TFL (IPG Photonics\u0026reg;, Russia) with a wavelength of 1940 nm, used a 272\u0026micro;m fibers. The second system was a diode-pumped solid-state (DPSS) p-Tm:YAG RevoLix HTL prototype (OmniGuide, USA) laser with a wavelength of 2013 nm, tested with both 200\u0026micro;m and 272\u0026micro;m fibers. Finally, we evaluated the performance of a 30 W Ho:YAG laser (MH1 Rocamed\u0026reg;, Monaco) with a wavelength of 2120 nm, also coupled with 272 \u0026micro;m fibers.\u003c/p\u003e\u003cp\u003e\u003cb\u003eStone phantoms\u003c/b\u003e\u003c/p\u003e\u003cp\u003eBegoStones measuring 1cm\u0026sup3; were fabricated following previously described methods(\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e). To replicate calcium oxalate monohydrate (Hard) and uric acid (Soft) stones, we used a \u0026ldquo;powder-to-water\u0026rdquo; ratio of 15:3 for Hard stones and 15:5 for Soft stones. After shaping, the samples underwent a 48-hour drying period at 30\u0026deg;C to reduce heterogeneity.\u003c/p\u003e\u003cp\u003e\u003cb\u003eExperimental setup\u003c/b\u003e\u003c/p\u003e\u003cp\u003eStone phantoms were fully submerged in saline solution at room temperature and securely fixed within a bench model. To evaluate the performance of the TFL, p-Tm:YAG, and Ho:YAG lasers, we used 272 \u0026micro;m fibers. Additionally, the ablation efficiency of the p-Tm:YAG laser was also assessed using a 200 \u0026micro;m fiber. The laser fiber tip was positioned perpendicularly and kept in direct contact with the stone surface. A custom-designed fiber support was developed to ensure complete stability during laser emission. To minimize the \u0026ldquo;burnback effect\u0026rdquo;, we adopted a \u0026ldquo;one locus-one pulse\u0026rdquo; approach(\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e). A six-axis robotic arm (KR6R900, Kuka International \u0026copy;, Germany) was employed to execute a precisely programmed spiral trajectory.\u003c/p\u003e\u003cp\u003eLaser emission and robotic arm movement were synchronized and controlled via computational command. The laser fiber followed an Archimedean Type-4 spiral trajectory for 20 seconds, with a 4 mm radius and a constant 1.2 mm spacing between spiral turns. Regarding laser settings, three different configurations were tested for all laser types: 0.2 J \u0026ndash; 50 Hz, 0.5 J \u0026ndash; 20 Hz, and 1 J \u0026ndash; 10 Hz. While TFL was operated in short pulse mode, the Ho:YAG were set to long pulse mode and the p-Tm:YAG laser was set to 50%.\u003c/p\u003e\u003cp\u003eEach test was performed in three times to ensure reproducibility. Following laser emission, the stones were dried according to previously described protocols. Three-dimensional imaging of the artificial stones was conducted using a micro-CT scanner (Quantum FX, Perkin Elmer\u0026copy;), and volumetric analysis was carried out through 3D segmentation using 3DSlicer software (NIH\u0026copy;) [11] [Figures \u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e and \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e]. All volumetric analyses were reviewed by a single operator (A.Q.) to eliminate inter-individual variability.\u003c/p\u003e\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003eStatistical analysis\u003c/h2\u003e\u003cp\u003eFor the analysis of ablation rates, a two-tailed Student's t-test was performed using IBM SPSS Statistics for Macintosh, Version 29.0.2.0 (IBM Corp., Armonk, NY, 2023). A p-value of less than 0.05 was considered statistically significant.\u003c/p\u003e\u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eThe comparison of ablation rates among the Ho:YAG, TFL, and p-Tm:YAG lasers revealed significant differences in performance depending on the laser type, energy settings, and stone composition.\u003c/p\u003e\u003cp\u003eFor hard stones, the TFL laser consistently demonstrated absolute higher ablation rates than both the p-Tm:YAG and Ho:YAG lasers at all energy settings. Although the difference between TFL and p-Tm:YAG was not statistically significant (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05), the TFL exhibited significantly greater ablation efficiency than the Ho:YAG laser, particularly at 0.5 J \u0026minus;\u0026thinsp;20 Hz (27.90 mm3/min \u0026plusmn; 8.83 vs 16.84 mm3/min \u0026plusmn; 1.17 - p\u0026thinsp;=\u0026thinsp;0.04) and 1.0 J \u0026minus;\u0026thinsp;10 Hz (29.53 mm3/min \u0026plusmn; 3.66 vs 20.86 mm3/min \u0026plusmn; 1.76 - p\u0026thinsp;=\u0026thinsp;0.01). The p-Tm:YAG laser also outperformed the Ho:YAG laser at 0.5 J \u0026minus;\u0026thinsp;20 Hz (22.96 mm3/min \u0026plusmn; 3.03 vs 16.84 \u0026plusmn; 1.17 - p\u0026thinsp;=\u0026thinsp;0.01), but no significant difference was observed at 1.0 J \u0026minus;\u0026thinsp;10 Hz (25.02 mm3/min \u0026plusmn; 6.42 vs 20.86 mm3/min \u0026plusmn; 1.76 - p\u0026thinsp;=\u0026thinsp;0.17) [Tables\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e \u0026ndash; \u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison between TFL and Tm:YAG lasers.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cem\u003eInterface\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cem\u003eLaser settings\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e\u003cp\u003e\u003cem\u003eAblation rate (mm3/min)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003ep value\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003eTFL (mean\u003c/b\u003e \u003cem\u003e\u0026plusmn;\u003c/em\u003e \u003cb\u003eSD)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003ep-Tm:YAG (mean\u003c/b\u003e \u003cem\u003e\u0026plusmn;\u003c/em\u003e \u003cb\u003eSD)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e\u003cb\u003eHard Stones\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e0.20 J \u0026ndash; 50 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e25.95 (\u0026plusmn; 7.35)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e19.74 (\u0026plusmn; 1.16)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003e0.11\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e0.5 J \u0026minus;\u0026thinsp;20 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e27.90 (\u0026plusmn; 8.83)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e22.96 (\u0026plusmn; 3.03)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003e0.21\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e1.0 J -10 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e29.53 (\u0026plusmn; 3.66)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e25.02 (\u0026plusmn; 6.42)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003e0.18\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e\u003cb\u003eSoft Stones\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e0.20 J \u0026ndash; 50 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e30.83 (\u0026plusmn; 3.55)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e25.76 (\u0026plusmn; 0.17)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.03\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e0.5 J \u0026minus;\u0026thinsp;20 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e32.65 (\u0026plusmn; 1.76)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e24.95 (\u0026plusmn; 0.90)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.00\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e1.0 J -10 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e33.64 (\u0026plusmn; 5.19)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e27.16 (\u0026plusmn; 8.43)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003e0.16\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison between TFL and Ho:YAG lasers.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cem\u003eInterface\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cem\u003eLaser settings\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e\u003cp\u003e\u003cem\u003eAblation rate (mm3/min)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003ep value\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003eTFL (mean\u003c/b\u003e \u003cem\u003e\u0026plusmn;\u003c/em\u003e \u003cb\u003eSD)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003eHo:YAG (mean\u003c/b\u003e \u003cem\u003e\u0026plusmn;\u003c/em\u003e \u003cb\u003eSD)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e\u003cb\u003eHard Stones\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e0.20 J \u0026ndash; 50 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e25.95 (\u0026plusmn; 7.35)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003eNA\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003eNA\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e0.5 J \u0026minus;\u0026thinsp;20 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e27.90 (\u0026plusmn; 8.83)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e16.84 (\u0026plusmn; 1.17)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.04\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e1.0 J -10 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e29.53 (\u0026plusmn; 3.66)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e20.86 (\u0026plusmn; 1.76)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.01\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e\u003cb\u003eSoft Stones\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e0.20 J \u0026ndash; 50 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e30.83 (\u0026plusmn; 3.55)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003eNA\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003eNA\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e0.5 J \u0026minus;\u0026thinsp;20 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e32.65 (\u0026plusmn; 1.76)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e16.57 (\u0026plusmn; 8.38)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.02\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e1.0 J -10 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e33.64 (\u0026plusmn; 5.19)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e18.57 (\u0026plusmn; 3.03)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.00\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison between Ho:YAG and Tm:YAG lasers.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cem\u003eInterface\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cem\u003eLaser settings\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e\u003cp\u003e\u003cem\u003eAblation rate (mm3/min)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003ep value\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003ep-Tm:YAG (mean\u003c/b\u003e \u003cem\u003e\u0026plusmn;\u003c/em\u003e \u003cb\u003eSD)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003eHo:YAG (mean\u003c/b\u003e \u003cem\u003e\u0026plusmn;\u003c/em\u003e \u003cb\u003eSD)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e\u003cb\u003eHard Stones\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e0.20 J \u0026ndash; 50 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e19.74 (\u0026plusmn; 1.16)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003eNA\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003eNA\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e0.5 J \u0026minus;\u0026thinsp;20 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e22.96 (\u0026plusmn; 3.03)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e16.84 (\u0026plusmn; 1.17)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.01\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e1.0 J -10 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e25.02 (\u0026plusmn; 6.42)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e20.86 (\u0026plusmn; 1.76)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003e0.17\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e\u003cb\u003eSoft Stones\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e0.20 J \u0026ndash; 50 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e25.76 (\u0026plusmn; 0.17)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003eNA\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003eNA\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e0.5 J \u0026minus;\u0026thinsp;20 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e24.95 (\u0026plusmn; 0.90)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e16.57 (\u0026plusmn; 8.38)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003e0.08\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e1.0 J -10 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e27.16 (\u0026plusmn; 8.43)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e18.57 (\u0026plusmn; 3.03)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003e0.08\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eFor soft stones, the TFL laser demonstrated superior ablation rates compared to both the p-Tm:YAG and Ho:YAG lasers. The difference between TFL and Tm:YAG was statistically significant at lower energy settings, with p-values of 0.03 (30.83 mm3/min \u0026plusmn; 3.55 vs 25.76 mm3/min \u0026plusmn; 0.17) and 0.00 (32.65 mm3/min \u0026plusmn; 1.76 vs 24.95 mm3/min \u0026plusmn; 0.90) for 0.20 J \u0026minus;\u0026thinsp;50 Hz and 0.5 J \u0026minus;\u0026thinsp;20 Hz, respectively. In the comparison between TFL and Ho:YAG, TFL showed significantly higher ablation rates at all tested energy settings (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Additionally, p-Tm:YAG outperformed Ho:YAG for soft stones at 0.5 J \u0026minus;\u0026thinsp;20 Hz and 1.0 J \u0026minus;\u0026thinsp;10 Hz, though the differences were not statistically significant (p\u0026thinsp;=\u0026thinsp;0.08 for both) [Tables\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e \u0026ndash; \u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eFinally, the comparison of ablation efficiency between 200 \u0026micro;m and 272 \u0026micro;m fibers using the Tm:YAG laser showed that the 272 \u0026micro;m fiber resulted in significantly higher ablation rates for both hard and soft stones at lower energy settings. Statistically significant differences were observed at 0.20 J \u0026minus;\u0026thinsp;50 Hz and 0.5 J \u0026minus;\u0026thinsp;20 Hz for both stone types [Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison of 200 \u0026micro;m vs 272 \u0026micro;m fibers in Tm:YAG laser.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cem\u003eInterface\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cem\u003eLaser settings\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e\u003cp\u003e\u003cem\u003eAblation rate (mm3/min)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003ep value\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e200um (mean\u003c/b\u003e \u003cem\u003e\u0026plusmn;\u003c/em\u003e \u003cb\u003eSD)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003e272um (mean\u003c/b\u003e \u003cem\u003e\u0026plusmn;\u003c/em\u003e \u003cb\u003eSD)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e\u003cem\u003eHard Stones\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e0.20 J \u0026ndash; 50 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e15.93 (\u0026plusmn; 0.83)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e19.74 (\u0026plusmn; 1.16)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.00\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e0.5 J \u0026minus;\u0026thinsp;20 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e17.09 (\u0026plusmn; 1.58)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e22.96 (\u0026plusmn; 3.03)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.02\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e1.0 J -10 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e19.30 (\u0026plusmn; 0.50)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e25.02 (\u0026plusmn; 6.42)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003e0.10\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e\u003cem\u003eSoft Stones\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e0.20 J \u0026ndash; 50 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e20.65 (\u0026plusmn; 1.92)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e25.76 (\u0026plusmn; 0.17)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.01\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e0.5 J \u0026minus;\u0026thinsp;20 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e22.39 (\u0026plusmn; 0.84)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e24.95 (\u0026plusmn; 0.90)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.01\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003e1.0 J -10 Hz\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003e22.72 (\u0026plusmn; 3.56)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003e27.16 (\u0026plusmn; 8.43)\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003e0.22\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study provides a comprehensive comparison of TFL, p-Tm:YAG, and Ho:YAG lasers for kidney stone ablation using a standardized robotic arm. Notably, this is the first comparative study to incorporate a fully automated mechanical robotic arm, ensuring precise and reproducible conditions for laser evaluation.\u003c/p\u003e\u003cp\u003eOur results demonstrate that p-Tm:YAG achieves excellent ablation efficiency across the two stone-phantom compositions designed to mimic calcium oxalate monohydrate (COM) and uric-acid (UA) stones. These findings are in line with earlier work showing that p-Tm:YAG effectively ablates both COM and UA stones without statistically significant differences, confirming its robust performance irrespective of stone composition or laser settings(\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eImportantly, we acknowledge that the definition and fabrication of our phantoms are grounded in their acoustical\u0026mdash;rather than optical\u0026mdash;characteristics, following the approach described by Esch et al., which matches the elastic and fracture properties that dominate fragmentation dynamics(\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eEarly clinical experiences have demonstrated the effectiveness and safety of Dornier p-Tm:YAG in flexible ureteroscopic lithotripsy, yielding comparable stone-free rates to TFL (75% vs. 77%, p\u0026thinsp;=\u0026thinsp;0.8), albeit with a slightly lower dusting efficiency (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eRecent systematic reviews confirm that p-Tm:YAG is a viable alternative to Ho:YAG and TFL, offering a balance between these technologies for endoscopic lithotripsy applications. Additionally, purely p-Tm:YAG lasers have shown promising safety and efficacy in RIRS and PCNL, with their higher PP compared to TFL enabling efficient stone disintegration and effective pulverization(\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eOur findings indicate that for hard stones, TFL consistently demonstrated higher ablation rates than both Tm:YAG and Ho:YAG, regardless of energy settings. The difference between TFL and Tm:YAG was not statistically significant, however, TFL significantly outperformed Ho:YAG at 0.5 J \u0026minus;\u0026thinsp;20 Hz and 1.0 J \u0026minus;\u0026thinsp;10 Hz.\u003c/p\u003e\u003cp\u003eWhile both p-Tm:YAG and TFL outperformed Ho:YAG, a key distinction emerged in their dusting efficiency. A recent study shows that p-Tm:YAG produced lower zero fragmentation rates (ZFR) than TFL (39% vs. 64%, p\u0026thinsp;=\u0026thinsp;0.008), suggesting a relatively low ability to generate particulate matter(\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e). This implies that TFL remains superior for dusting strategies, whereas p-Tm:YAG maintains a balanced profile between fragmentation and dusting (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e). Notably, Tm:YAG also exhibited higher efficiency than Ho:YAG at 0.5 J \u0026minus;\u0026thinsp;20 Hz (p\u0026thinsp;=\u0026thinsp;0.01). These results suggest that while TFL is the most effective option for hard stone ablation, Tm:YAG still provides significant advantages over Ho:YAG, particularly at certain energy settings.\u003c/p\u003e\u003cp\u003eFor soft stones, TFL demonstrated superior ablation rates compared to both Tm:YAG and Ho:YAG, with statistically significant differences at lower energy settings. Additionally, the comparison between TFL and Ho:YAG confirmed TFL\u0026rsquo;s superior performance, as it achieved significantly higher ablation rates across all tested energy settings (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Although Tm:YAG outperformed Ho:YAG at 0.5 J \u0026minus;\u0026thinsp;20 Hz and 1.0 J \u0026minus;\u0026thinsp;10 Hz, these differences were not statistically significant (p\u0026thinsp;=\u0026thinsp;0.08 for both).\u003c/p\u003e\u003cp\u003eThese findings align with recent literature. A recent in vitro study by Sierra del Rio et al., reported that both p-Tm:YAG and TFL exhibited superior performance in laser lithotripsy compared to Ho:YAG, demonstrating higher efficiency and ablation speed. Moreover, thermal damage was not linked to a specific laser type but was instead associated with increasing power settings(\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). Additionally, a recent study by Petzold et al. showed that longer pulse durations significantly enhance Tm:YAG\u0026rsquo;s ablation rates compared to Ho:YAG, further supporting its efficacy(\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eFrom a technical perspective, the p-Tm:YAG laser represents an intermediate option between Ho:YAG and TFL, balancing key properties such as PP, a uniform pulse profile, and reduced risk of fiber fracture in vitro. The lower PP and more uniform pulse profile of both TFL and p-Tm:YAG play a major role in reducing retropulsion, allowing for prolonged contact between the fiber tip and the stone. This extended interaction enhances fragmentation efficiency, positioning both p-Tm:YAG and TFL as superior to Ho:YAG in terms of ablation performance (\u003cspan additionalcitationids=\"CR20 CR21\" citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eFinally, our study demonstrated that using a 272 \u0026micro;m fiber with the Tm:YAG laser resulted in significantly higher ablation rates than the 200 \u0026micro;m fiber for both hard and soft stones at lower energy settings, with statistically significant differences observed at 0.20 J \u0026minus;\u0026thinsp;50 Hz and 0.5 J \u0026minus;\u0026thinsp;20 Hz. These findings are consistent with those reported by Panthier et al. (2020) for TFL and Ho:YAG, reinforcing the importance of fiber diameter in optimizing laser lithotripsy efficiency (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e). In clinical practice, however, smaller fibers are commonly used with TFL, typically 150 \u0026micro;m, differing from the larger diameters often employed with other lasers.\u003c/p\u003e\u003cp\u003eDespite its novelty, the current study has several limitations. BegoStones phantoms are widely used in vitro due to their consistency and ease of handling, however, they do not fully replicate the optical absorption and thermal properties of human stones. Consequently, laser settings effective on BegoStones phantoms may not yield identical results in clinical practice due to differences in absorption, fragmentation patterns, and thermal interactions. Nonetheless, their use provides a controlled and reproducible model for evaluating laser performance.\u003c/p\u003e\u003cp\u003eIt is also important to underline that our model does not allow for a detailed analysis of fragment size or composition, since only fine dust is generated with stone phantoms. As a result, we were unable to investigate the fragmentation pattern or potential for clinically relevant fragments, which is a crucial outcome when treating real human stones. In vivo studies could provide valuable insights into this aspect, as has already been shown for Thulium Fiber Laser (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eMoreover, although this study focuses on ablation rate as a primary endpoint, it should be noted that in clinical practice the ultimate success criteria are stone-free rates (SFR) and the need for retreatment, which depend not only on ablation efficiency but also on fragmentation characteristics, retropulsion, and the ability to clear residual fragments.\u003c/p\u003e\u003cp\u003eFrom a mechanistic standpoint, while it is generally accepted that stone ablation occurs through laser-induced energy absorption by the stone surface, the dominant underlying mechanism, whether photothermal or photomechanical, remains a matter of ongoing investigation. It is currently hypothesized that thermal effects play a primary role, particularly with TFL and p-Tm:YAG lasers due to their lower peak power and longer pulse duration, which promote gradual energy deposition and heat-driven disintegration. Some studies have contributed significantly to this understanding and support the predominance of thermal mechanisms, although the interplay with photomechanical forces cannot be excluded (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e).\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eTFL confirmed to be the most effective laser for in vitro lithotripsy, while p-Tm:YAG provides a promising middle-ground solution. Indeed, p-Tm:YAG represents a viable alternative to Ho:YAG, offering a balance between fragmentation and dusting efficiency.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003ch2\u003eConflict of Interest Statement:\u003c/h2\u003e\u003cp\u003eOlivier Traxer has declared as consultant for Karl Storz, Coloplast, IPG photonics, Ambu, Quanta System and Rocamed. Fr\u0026eacute;d\u0026eacute;ric Panthier has declared as consultant for Dornier. All other authors have no conflict of interest.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eSource of funding\u003c/strong\u003e\u003cp\u003enone.\u003c/p\u003e\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eQuar\u0026agrave; - Conceptualization, Methodology, Data curation, Writing-Original draft preparation; Bravo-Balado - Conceptualization, Methodology, Data curation; Moretto - Conceptualization, Methodology, Data curation; Madden - Data curation; Zorzi - Data curation; Jannello - Writing - Review \u0026amp; Editing; Kutchukian - Writing - Review \u0026amp; Editing, Cabrera - Methodology, Data curation; Corrales - Methodology, Data curation; Chicaud - Methodology, Data curation; Gradilone - Data curation, Candela - Data curation, Writing - Review \u0026amp; Editing, Gorny - Methodology, Data curation; Coste - Methodology, Data curation; Berthe L. - Methodology, Data curation; Doizi - Writing - Review \u0026amp; Editing, Supervision; Panthier - Writing - Review \u0026amp; Editing, Supervision; Fiori - Writing - Review \u0026amp; Editing, Supervision; Traxer - Writing - Review \u0026amp; Editing, Supervision\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eNone.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eKronenberg P, Cerrato C, Julieb\u0026oslash;-Jones P, Herrmann T, Tokas T, Somani BK. Advances in lasers for the minimally invasive treatment of upper and lower urinary tract conditions: a systematic review. World J Urol [Internet]. 2023 Dec 1 [cited 2025 Apr 1];41(12):3817\u0026ndash;27. Available from: https://pubmed-ncbi-nlm-nih-gov.bibliopass.unito.it/37906263/\u003c/li\u003e\n\u003cli\u003eSofer M, Watterson JD, Wollin TA, Nott L, Razvi H, Denstedt JD. Holmium:YAG laser lithotripsy for upper urinary tract calculi in 598 patients. J Urol [Internet]. 2002 [cited 2025 Apr 1];167(1):31\u0026ndash;4. Available from: https://pubmed-ncbi-nlm-nih-gov.bibliopass.unito.it/11743269/\u003c/li\u003e\n\u003cli\u003eMoretto S, Quar\u0026agrave; A, Zorzi F, Bravo‐Balado A, Madden A, Cabrera J, et al. Stone dust in endourology: a systematic review of its definition, management, and clinical impact. BJU Int [Internet]. 2025 May 9; Available from: https://bjui-journals.onlinelibrary.wiley.com/doi/10.1111/bju.16765\u003c/li\u003e\n\u003cli\u003eUleri A, Farr\u0026eacute; A, Izquierdo P, Angerri O, Kanashiro A, Bala\u0026ntilde;a J, et al. Thulium Fiber Laser Versus Holmium:Yttrium Aluminum Garnet for Lithotripsy: A Systematic Review and Meta-analysis. Eur Urol [Internet]. 2024 Jun 1 [cited 2025 Apr 1];85(6):529\u0026ndash;40. Available from: https://pubmed-ncbi-nlm-nih-gov.bibliopass.unito.it/38290963/\u003c/li\u003e\n\u003cli\u003eKeller EX, De Coninck V, Doizi S, Daudon M, Traxer O. Thulium fiber laser: ready to dust all urinary stone composition types? World J Urol [Internet]. 2021 [cited 2025 Apr 1];39(6). Available from: https://pubmed-ncbi-nlm-nih-gov.bibliopass.unito.it/32363450/\u003c/li\u003e\n\u003cli\u003eTraxer O, Keller EX. Thulium fiber laser: the new player for kidney stone treatment? A comparison with Holmium:YAG laser. World J Urol [Internet]. 2020 Aug 1 [cited 2025 Apr 1];38(8):1883\u0026ndash;94. Available from: https://pubmed-ncbi-nlm-nih-gov.bibliopass.unito.it/30729311/\u003c/li\u003e\n\u003cli\u003eBravo-Balado A, Moretto S, Jannello LMI, Quar\u0026agrave; A, Zorzi F, Doizi S, et al. High-frequency in laser lithotripsy: do we truly know what it means? World J Urol [Internet]. 2025 May 8;43(1):287. Available from: https://link.springer.com/10.1007/s00345-025-05650-0\u003c/li\u003e\n\u003cli\u003eSierra del Rio A, Panthier F, Castillo E, Mercad\u0026eacute; A, Peri L, Alcaraz A, et al. Assessment of Holmium:YAG, pulsed-Thulium:YAG and Thulium Fiber Lasers for Urinary Stone Ablation. In vitro study. J Endourol. 2024 Sep 24; \u003c/li\u003e\n\u003cli\u003eKraft L, Petzold R, Suarez-Ibarrola R, Miernik A. In vitro fragmentation performance of a novel, pulsed Thulium solid-state laser compared to a Thulium fibre laser and standard Ho:YAG laser. Lasers Med Sci [Internet]. 2022 Apr 1 [cited 2025 Apr 1];37(3):2071\u0026ndash;8. Available from: https://pubmed-ncbi-nlm-nih-gov.bibliopass.unito.it/34905141/\u003c/li\u003e\n\u003cli\u003ePanthier F, Doizi S, Lapouge P, Chaussain C, Kogane N, Berthe L, et al. Comparison of the ablation rates, fissures and fragments produced with 150 \u0026micro;m and 272 \u0026micro;m laser fibers with superpulsed thulium fiber laser: an in vitro study. World J Urol. 2020; \u003c/li\u003e\n\u003cli\u003eEsch E, Simmons WN, Sankin G, Cocks HF, Preminger GM, Zhong P. A simple method for fabricating artificial kidney stones of different physical properties. Urol Res [Internet]. 2010 Aug [cited 2025 Mar 28];38(4):315\u0026ndash;9. Available from: https://pubmed.ncbi.nlm.nih.gov/20652562/\u003c/li\u003e\n\u003cli\u003ePeplinski B, Faaborg D, Miao E, Alsyouf M, Myklak K, Kelln W, et al. The Effect of Laser Fiber Cleave Technique and Lithotripsy Time on Power Output. J Endourol [Internet]. 2016 Jun 1 [cited 2025 Mar 28];30(6):678\u0026ndash;84. Available from: https://pubmed.ncbi.nlm.nih.gov/26872709/\u003c/li\u003e\n\u003cli\u003eKwok JL, Ventimiglia E, De Coninck V, Panthier F, Barghouthy Y, Danilovic A, et al. Pulsed Thulium:YAG laser \u0026ndash; What is the lithotripsy ablation efficiency for stone dust from human urinary stones? Results from an in vitro PEARLS study. World J Urol. 2023 Dec 1;41(12):3723\u0026ndash;30. \u003c/li\u003e\n\u003cli\u003eProietti S, Marchioni M, Oo MM, Scalia R, Gisone S, Monroy RE, et al. Flexible Ureteroscopic Lithotripsy with the Pulsed Thulium:Yttrium Aluminum Garnet Laser Thulio: Preliminary Results from a Prospective Study. Eur Urol Open Sci. 2024 Sep 1;67:77\u0026ndash;83. \u003c/li\u003e\n\u003cli\u003ePanthier F, Solano C, Chicaud M, Kutchukian S, Candela L, Doizi S, et al. Thulium fiber laser versus pulsed Thulium:YAG for laser lithotripsy during flexible ureteroscopy. Lasers Med Sci. 2024 Dec 1;39(1). \u003c/li\u003e\n\u003cli\u003eVentimiglia E, Robesti D, Bevilacqua L, Tondelli E, Oliva I, Orecchia L, et al. What to expect from the novel pulsed thulium:YAG laser? A systematic review of endourological applications. World J Urol. 2023 Nov 1;41(11):3301\u0026ndash;8. \u003c/li\u003e\n\u003cli\u003eKallidonis P, Spinos T, Guven S, Tatanis V, Peteinaris A, Liatsikos E, et al. Pulsed Thulium: YAG laser for the management of Urolothiasis: a systematic review from the EAU section of endourology. Vol. 43, World journal of urology. 2025. p. 118. \u003c/li\u003e\n\u003cli\u003ePetzold R, Miernik A, Suarez-Ibarrola R. In Vitro Dusting Performance of a New Solid State Thulium Laser Compared to Holmium Laser Lithotripsy. J Endourol. 2021 Feb 1;35(2):221\u0026ndash;5. \u003c/li\u003e\n\u003cli\u003ePetzold R, Miernik A, Suarez-Ibarrola R. Retropulsion force in laser lithotripsy-an in vitro study comparing a Holmium device to a novel pulsed solid-state Thulium laser. World J Urol [Internet]. 2021 Sep 1 [cited 2025 Apr 1];39(9):3651\u0026ndash;6. Available from: https://pubmed-ncbi-nlm-nih-gov.bibliopass.unito.it/33758959/\u003c/li\u003e\n\u003cli\u003eVentimiglia E, Villa L, Doizi S, Briganti A, Proietti S, Giusti G, et al. Laser Lithotripsy: The Importance of Peak Power and Pulse Modulation. Eur Urol Focus [Internet]. 2021 Jan 1 [cited 2025 Apr 1];7(1):22\u0026ndash;5. Available from: https://pubmed-ncbi-nlm-nih-gov.bibliopass.unito.it/33531287/\u003c/li\u003e\n\u003cli\u003eVentimiglia E, Doizi S, Kovalenko A, Andreeva V, Traxer O. Effect of temporal pulse shape on urinary stone phantom retropulsion rate and ablation efficiency using holmium:YAG and super-pulse thulium fibre lasers. BJU Int [Internet]. 2020 Jul 1 [cited 2025 Apr 1];126(1):159\u0026ndash;67. Available from: https://pubmed-ncbi-nlm-nih-gov.bibliopass.unito.it/32277557/\u003c/li\u003e\n\u003cli\u003eChicaud M, Kutchukian S, Berthe L, Corrales M, Solano C, Candela L, et al. In Vitro Comparison of Pulsed-Thulium:YAG, Holmium:YAG, and Thulium Fiber Laser. J Endourol. 2024 Dec 1; \u003c/li\u003e\n\u003cli\u003eVassar GJ, Chan KF, Teichman JMH, Glickman RD, Weintraub ST, Pfefer TJ, et al. Holmium: YAG lithotripsy: photothermal mechanism. J Endourol [Internet]. 1999 [cited 2025 Jul 8];13(3):181\u0026ndash;90. Available from: https://pubmed.ncbi.nlm.nih.gov/10360498/\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"world-journal-of-urology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"wjur","sideBox":"Learn more about [World Journal of Urology](https://link.springer.com/journal/345)","snPcode":"345","submissionUrl":"https://submission.nature.com/new-submission/345/3","title":"World Journal of Urology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Laser Lithotripsy, Ho:YAG, Pulsed Thulium:YAG Laser, Thulium Fiber Laser, Ablation, Kidney Stones","lastPublishedDoi":"10.21203/rs.3.rs-7160763/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7160763/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eObjective\u003c/h2\u003e\u003cp\u003eThis study compares the ablation rates of three laser systems\u0026mdash;Holmium:YAG (Ho:YAG), Thulium Fiber Laser (TFL), and Pulsed Thulium:YAG (p-Tm:YAG)\u0026mdash;for renal stone lithotripsy using a standardized robotic setup.\u003c/p\u003e\u003ch2\u003eMaterials and Methods\u003c/h2\u003e\u003cp\u003eA robotic arm enabled consistent laser application on stone phantoms simulating calcium oxalate monohydrate (hard) and uric acid (soft) stones. Ablation efficiency (mm\u0026sup3;/J) was assessed across different laser settings (0.2 J \u0026ndash; 50 Hz, 0.5 J \u0026ndash; 20 Hz, and 1.0 J \u0026ndash; 10 Hz) and fiber diameters (200 and 272 \u0026micro;m). Ablated volumes were quantified via micro-CT and 3D segmentation using 3DSlicer. Statistical analysis evaluated differences in performance.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eTFL demonstrated the highest ablation rates for both hard and soft stones, significantly outperforming Ho:YAG in multiple settings. For hard stones, TFL exhibited greater ablation efficiency than Ho:YAG, particularly at 0.5 J \u0026minus;\u0026thinsp;20 Hz and 1.0 J \u0026minus;\u0026thinsp;10 Hz. The p-Tm:YAG laser also outperformed Ho:YAG at 0.5 J \u0026minus;\u0026thinsp;20 Hz. For soft stones, the difference between TFL and Tm:YAG was statistically significant at lower energy settings (0.20 J \u0026minus;\u0026thinsp;50 Hz and 0.5 J \u0026minus;\u0026thinsp;20 Hz). Compared to Ho:YAG, TFL showed significantly higher ablation rates across all tested settings (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The p-Tm:YAG laser showed intermediate performance, with higher efficiency than Ho:YAG but slightly lower than TFL. Fiber diameter influenced ablation, with 272 \u0026micro;m fibers yielding greater efficiency at lower energy settings (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05 at 0.20 J \u0026minus;\u0026thinsp;50 Hz and 0.5 J \u0026minus;\u0026thinsp;20 Hz for both stone types); this comparison was limited to p-Tm:YAG, as data for the other lasers are already available in the literature.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e\u003cp\u003eTFL achieved the highest in vitro ablation efficiency. However, p-Tm:YAG represents a promising compromise, offering improved performance over Ho:YAG and a balanced profile between fragmentation and dusting capabilities.\u003c/p\u003e","manuscriptTitle":"In Vitro Ablation Rates of Ho:YAG, p-Tm:YAG and TFL Lasers","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-20 09:25:16","doi":"10.21203/rs.3.rs-7160763/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-08-21T10:29:10+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-08-15T16:43:54+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"271238438551727619887404094640140212249","date":"2025-08-13T15:57:09+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-08-13T11:23:58+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"313880697449827265697001184780400422153","date":"2025-08-13T11:01:08+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-08-12T17:44:54+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-07-19T16:39:42+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-07-19T05:20:16+00:00","index":"","fulltext":""},{"type":"submitted","content":"World Journal of Urology","date":"2025-07-18T21:53:16+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"world-journal-of-urology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"wjur","sideBox":"Learn more about [World Journal of Urology](https://link.springer.com/journal/345)","snPcode":"345","submissionUrl":"https://submission.nature.com/new-submission/345/3","title":"World Journal of Urology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"b417fff2-25bb-4a1c-b776-8af480d5dfb5","owner":[],"postedDate":"August 20th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-11-17T15:58:54+00:00","versionOfRecord":{"articleIdentity":"rs-7160763","link":"https://doi.org/10.1007/s00345-025-06001-9","journal":{"identity":"world-journal-of-urology","isVorOnly":false,"title":"World Journal of Urology"},"publishedOn":"2025-11-10 15:56:53","publishedOnDateReadable":"November 10th, 2025"},"versionCreatedAt":"2025-08-20 09:25:16","video":"","vorDoi":"10.1007/s00345-025-06001-9","vorDoiUrl":"https://doi.org/10.1007/s00345-025-06001-9","workflowStages":[]},"version":"v1","identity":"rs-7160763","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7160763","identity":"rs-7160763","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}