YAG Laser Fiber Research Articles

Ejaculation-sparing enucleation of the prostate with Thulium: Yag laser (ES-ThuLEP) versus Thulium Fiber laser (ES-ThuFLEP): outcomes on sexual function.

To compare the effect on sexual function of ejaculation-sparing enucleation of the prostate using Thulium: YAG laser (ES-ThuLEP) versus continuous-wave Thulium Fiber Laser (ES-ThuFLEP). 112 patients with lower urinary tract symptoms secondary to benign prostatic hyperplasia who wished to preserve ejaculation were treated. 58 patients underwent ES-ThuLEP (Group A) using the Cyber TM generator. 54 patients underwent ES-ThuFLEP (Group B) using the Fiber Dust generator. Sexual function was evaluated through the International Index of Erectile Function 5 (IIEF-5) score, the four-item Male Sexual Health Questionnaire (MSHQ-EjD), personal satisfaction and the occurrence of haemospermia and painful ejaculation 3 and 6 months after surgery. Mean age of patients was 65.8 years in Group A and 66.7 years in Group B. Groups were comparable according to preoperative features. Mean preoperative IIEF-5 score was 18.8 in Group A and 17.9 in Group B (p = 0.14). In all cases an ejaculation-sparing procedure was performed sparing the tissue around the veru montanum and near the prostate apex. Three months after surgery mean IIEF-5 score was 19.3 in Group A and 18.0 in Group B (p = 0.12). Six months after surgery mean IIEF-5 score was 17.8 in Group A and 18.1 in Group B (p = 0.09). No significant differences were observed according to anterograde ejaculation (81.0% vs. 81.5%, p = 0.07), subjective satisfaction (72.4% vs. 74.1%, p = 0.10), painful ejaculation (10.3% vs. 11.1%, p = 0.14) and haemosparmia rate (12.1% vs. 14.8%, p = 0.08). Ejaculation and satisfaction rate were significantly higher with prostates ≥ 80ml in both groups. Ejaculation-sparing enucleation of the prostate effectively preserved sexual function in the majority of patients, with high rate of anterograde ejaculation and subjective satisfaction, low rates of painful ejaculation and haemospermia and no significant differences between Thulium: YAG and Thulium Fiber Laser. Preservation of ejaculation and personal satisfaction were significantly higher with prostates ≥ 80ml compared to smaller ones.

Assessment of Holmium:YAG, Pulsed-Thulium:YAG and Thulium Fiber Lasers for Urinary Stone Ablation. In Vitro Study.

Objective: To evaluate the ablation speed (AS), laser efficiency and direct thermal lesions during urinary stone lithotripsy with the current available laser technologies: Holmium:YAG (Ho:YAG), pulsed-Thulium:YAG (p-Tm:YAG) and thulium fiber laser (TFL) in vitro using different laser settings. Materials and Methods: Ho:YAG, p-Tm:YAG, and TFL laser system were used in an in vitro ureteral model with a volume of 125 mm3 Begostone. The following parameters were tested across all laser devices: 0.6J/10 Hz (6 W), 0.6 J/20 Hz (12 W), 1.5 J/10 Hz (15 W), and 1.5 J/20 Hz (30 W), employing short pulse width for all lasers and long pulse width for Ho:YAG and p-Tm:YAG. Ten participants conducted the experimental setup during 3-minutes laser on time, combining the laser technology, settings, and pulse widths, with a total of 20 different combinations. The efficiency, AS and ureteral damage resulting from each intervention were analyzed. Results: p-Tm:YAG and TFL demonstrated significantly higher efficiency compared with Ho:YAG (0.049 ± 0.02 Δgr/KJ and 0.042 ± 0.01 Δgr/KJ vs 0.029 ± 0.01 Δgr/KJ; p < 0.05). In all laser sources, as the power increases, the AS also increases (p < 0.05). Furthermore, only at high-energy settings (1.5 J) higher frequency led to increase AS (p < 0.05). Both, p-Tm:YAG and TFL exhibited higher AS compared to Ho:YAG (0.64 ± 0.33 Δgr/s and 0.62 ± 0.31 Δgr/s vs 0.44 ± 0.22 Δgr/s; p < 0.05). Regarding ureteral injuries, as the power increases, there is a higher chance of ureteral damage (p = 0.031). No differences were observed between laser technologies (p = 0.828). Conclusions: Both, p-Tm:YAG and TFL exhibited superior performances during laser lithotripsy compared with Ho:YAG, as they demonstrated higher efficiency and ablation speed. Thermal damage did not appear to be associated with specific laser equipment, but higher grades of lesions are described by increasing power.

The safety and efficacy of five surgical treatments in prostate enucleation: a network meta-analysis

PurposeThe aim of our study was to investigate the comparative outcomes of five different energy types on surgical efficacy and postoperative recovery in patients with benign prostate hyperplasia.MethodsThe literature was systematically reviewed on December 1st, 2023, encompassing studies retrieved from PubMed, Embase, Web of Science, and The Cochrane Library databases that incorporated clinical studies of holmium laser enucleation of the prostate (HoLEP), Thulium:YAG laser enucleation of the prostate (ThuLEP), transurethral plasmakinetic enucleation of prostate (PKEP), diode laser enucleation of the prostate (DiLEP) and thulium fiber laser enucleation of the prostate (ThuFLEP) in the treatment of prostatic hyperplasia. Two independent reviewers extracted study data and conducted quality assessments using the Cochrane Collaboration's Risk of Bias tool and Newcastle–Ottawa Scale (NOS). Network meta-analysis (NMA) was employed to indirectly analyze the outcomes of endoscopic enucleation of the prostate (EEP) techniques.ResultsThe study included a total of 38 studies, comprising 21 non-randomized controlled trials (nRCTs) and 17 randomized controlled trials (RCTs), incorporating five distinct techniques: holmium laser, Thulium:YAG laser, bipolar plasma, diode laser and thulium fiber laser. In comparing treatment durations, ThuLEP and HoLEP had shorter overall hospital stays than PKEP, while the enucleation time of ThuLEP and HoLEP was shorter than that of ThuFLEP. Moreover, the enucleation tissue weight of both thulium fiber laser and holmium laser was heavier than bipolar plasma. However, the analysis did not reveal any statistically significant variation in complications among the various types of enucleation. In postoperative follow-up, the IPSS at 3 months post-operation was superior in the Thulium:YAG laser group compared to the holmium laser group. The thulium fiber laser technique demonstrated significant advantages over other enucleation methods in terms of QoL and PVR at 12 months after surgery.ConclusionTheoretical properties may vary among different energy sources; however, there are no discernible clinical differences in operation-related parameters, postoperative complications, and postoperative follow-up. Therefore, the choice of laser does not significantly impact the outcome. However, due to the limited number of included studies, future research should focus on larger sample sizes and multicenter investigations to further validate the findings of this study.

Optimization of Laser Micro/Nano Processing of Silicon and Quartz

This research paper explores the application of three laser systems, namely the Nd:YAG laser, fiber laser, and CO2 laser, for the micro/nano machining of silicon and quartz materials. The experimental results demonstrate the successful formation of stable silicon nanoparticles with reduced dimensions. Additionally, a quartz sheet was utilized to create a microlens array. The laser microprocessing technique was enhanced through the implementation of design of experiments (DOE) analysis. A Box-Behnken design (BBD) software was employed to conduct 17 tests, investigating the influence of laser parameters on the microprocessing outcomes. The COMSOL software was utilized for theoretical calculations to determine the distribution of surface temperatures and subsurface temperatures of silicon and quartz. The maximum temperatures achieved were approximately 5700 K for silicon and 2630 K for quartz. Numerical optimization using DOE software improved the production of silicon nanoparticles and quartz microlens, producing silicon nanoparticles wavelength peak and absorption peak values of 318.2 nm and 0.39, respectively. Additionally, quartz microlens numerical aperture and surface roughness improved to 0.494 and 4.64 nm, respectively. Due to the precise control offered by the laser micro/nano machining process, the findings of this study hold potential for diverse applications in optoelectronics and biological imaging that can leverage the unique characteristics of silicon nanoparticles and microlens arrays.

Synthesis of Nano Silicon Using Lasers

Two lasers of the same wavelength (1.06 μm) and various specifications were employed to synthesize silicon nanoparticles. The experimental data reveal the formation of stable silicon nanoparticles with different features such as UV-vis absorption, photoluminescence spectrum, Raman spectrum, Zeta potential, and SEM morphology. Theoretical simulations using COMSOL software were adopted to estimate the surface temperature distribution at the silicon surface and underneath. It is found that maximum temperatures of about (5700 K) and (4600 K) were generated when a Q-switched laser pulse of (10 ns) and fiber laser pulse of (127 ns) were used, respectively. While the recoil pressure at the silicon surface was (6.5*105 N/m2) and (1*103 N/m2) when Nd:YAG and fiber laser were used respectively. It found that increasing the laser energy for Nd:YAG laser and fiber laser power leads to a blue shift of the absorption spectra while the absorption intensity increases with the number of laser pulses and irradiation time. Raman spectroscopy for the prepared silicon nanoparticles was carried out. The Raman peaks for silicon nanoparticles reveal the formation of amorphous silicon. These peaks were observed at (482) and (475 cm-1) when Nd:YAG and fiber lasers were used to produce those nanoparticles. While the photoluminescence of the prepared silicon nanoparticles exhibits peaks at (457 nm) and (495 nm) for Nd:YAG and fiber lasers. The zeta potential reveals that silicon nanoparticle stability is greater for nanoparticles produced by fiber lasers (27 mv) than those produced by Nd:YAG lasers (17 mv) for three months. The corresponding silicon nanoparticle sizes refer to (3.8 nm) and (6 nm). Potential applications of silicon nanoparticles in optoelectronics and biological imaging can be conducted due to the controllable laser micro/nano machining process.

Micro-machining of SDSS-2507 under comparative assessment of fiber laser scan techniques

ABSTRACT Dual phases with different thermal characteristics make SDSS-2507 complex to process by laser. Therefore, two micro-machining attempts were made on SDSS-2507 using a Yb: YAG fiber laser to investigate the after-effect consequences. The current research studied existing (area fill-spacing) and unique (linear-orbit-in-orbit) scan modes using power, frequency, and transverse speed factors by fabricating micro-channels. Criteria-based multi-factor particle swarm optimization was further used to achieve adequate micro-channel characteristics. In order to provide insight into contemporary scanning modes, the current research also scrutinized surface morphology, elemental composition, phase quantification, micro-hardness, crystallite size, and lattice strain. The current research outcomes revealed that the unique scan mode strengthens the grain boundary in the present micro-machining process by reducing crystallite size. The comparative study revealed that the unique scan mode offers a reduced taper angle with a deeper channel profile, which might be a possible way to enhance micro-channel effectiveness for marine heat exchanger applications.

A REVIEW ON LASER MACHINING OF ALUMUNIA CERAMIC

Alumina, renowned for its outstanding resistance to corrosion and heat, poses a formidable challenge due to its brittle nature when it comes to machining. Nonetheless, laser machining has emerged as a particularly suitable method for working with hard and brittle materials like alumina. While traditional machining techniques can also be effective, they often necessitate prolonged machining durations and significantly high tool wear rates, thereby driving up the overall machining costs. By employing experimentation and optimization techniques, laser machining technologies such as Nd: YAG lasers, fiber lasers, and CO2 lasers have displayed remarkable efficacy in machining alumina. Notably, CO2 lasers offer distinctive advantages owing to their maximum power output of 45 kW and laser wavelength of 10.6 μm, rendering them suitable for macro material cutting applications. This paper aims to consolidate pertinent information on laser machining of alumina into a single document. The primary focus of this paper revolves around key laser machining parameters, including pulse duration, frequency, peak power, laser power, piercing time, gas pressure, and cutting speed, along with their impact on machining quality aspects such as surface irregularity, kerf width, taper angle, and the Heat-Affected Zone (HAZ).

Ablation rates with Holmium:YAG and Thulium Fiber Laser: Influence of the stone phantom homogeneity. An in vitro study.

The lithotripsy efficiency (LE) in vitro study requires artificial or human stone samples (AS, HS). With the development of dusting lithotripsy, less ex vivo HS are available. We aimed to compare Thulium Fiber Laser (TFL) and Holmium:YAG (Ho:YAG)'s LE and define the most accurate LE parameter. Hard and soft homogenous- and heterogenous-AS (Ho-AS, He-AS) were made to reproduce calcium-oxalate monohydrate and uric acid stones, respectively by a rapid or slow brewing of BegostonePlus (Bego) and distilled water. One hundred and fifty and 272μm-laser fibers, connected to 50W-TFL and 30W-HoYAG generators, compared three settings for TFL (FD: 0.15J/100Hz; D: 0.5J/30Hz; Fr: 1J/15Hz) and two for Ho:YAG (D-Fr). An experimental setup consisted in immerged 10mm cubic stone phantoms with a 20 seconds' lasing spiral, in contact mode, repeated four times. Stones were dried, weighted and μ-scanned (ablation weight and volume [AW and AV]). With He-AS, dusting AV were four- and three-fold higher with TFL compared to Ho:YAG against hard and soft (P<0.05). In fragmentation, AV were two-fold higher with TFL compared to Ho:YAG against hard (P<0.05) and soft (P<0.05). Experiments with Ho-AS were associated with non-significant differences when comparing TFL-150μm and TFL-272μm. The ablation weight-volume correlation coefficients was higher with Ho-AS than with He-AS (P<0.0001), and with hard than soft AS. If the LE can be estimated by the AW with hard AS, this approximation is not consistent for soft AS. TFL presented higher ablation rates than Ho:YAG, significant with He-AS. If the AW is acceptable and less expensive for hard Ho-AS, AV are more accurate for He-AS, which are suggested to imitate closely HS.

The combined treatment of fiber post and root canal by the Er:YAG laser enhances the bond strength of composite reconstruction.

Fiber post bonding failure remains an issue during crown restoration procedures. This experiment examines the bonding effect of combined Er:YAG laser treatment on both root canal and fiber post. Sixty extracted mandibular first premolars were randomly selected and divided into 6 groups (n = 10 per group): G1 (control group): root canal with 2.5% NaClO treatment, no treatment of fiber post; G2: root canal with 2.5% NaClO treatment and fiber post with airborne-particle abrasion; G3: root canal with Er:YAG laser treatment and fiber post with airborne-particle abrasion; G4: root canal with Er:YAG laser treatment, no treatment of fiber post; G5: root canal with 2.5% NaClO treatment, fiber post with Er:YAG laser irradiation; G6: combined Er:YAG laser irradiation of both root canal and fiber post. An Er:YAG laser with a wavelength of 2940nm was used to treat the fiber post (4.5 W, 450mJ, 10Hz for 60s at 100-μs pulse duration with 100% water cooling) and the root canal (1.5 W, 150mJ, 10Hz for 60s at 100-μs pulse duration with 100% water cooling). When the root canal was treated with the laser, the fiber tip was inserted into the root canal to make a spiral reciprocating motion. Bond strength was analyzed by a micro push-out test. Data were analyzed using both the Tukey test and two-way ANOVA (α = 0.05). Failure modes were observed and counted through a stereo microscope. The root canal and fiber post surface analysis was performed using SEM. The bond strength of G3 and G6 were significantly enhanced compared to those of the other groups (p < 0.05). The SEM analysis showed that the smear layers of groups with root canals subjected to Er:YAG laser irradiation were significantly reduced compared to those of the control group (G1). In groups with fiber posts treated with Er:YAG laser irradiation, the surfaces of the fiber posts exhibited greater surface roughness and a certain degree of epoxy matrix removal. Through the combined Er:YAG laser irradiation of both root canal and fiber post, the bond strength between them was significantly enhanced, which was superior to the individual treatment of either fiber posts or root canal.

Testing of a new Yb:YAG fiber laser system for the removal of graphic vandalism from marble

Graphic vandalism causes detrimental effects on architectural stone surfaces. Among the cleaning methods developed in the last decades, laser cleaning showed considerable effectiveness but the available equipment still lacks full adaptability for the use on site, while the cleaning process is time-consuming for the site work requirements. In this paper, the feasibility of a fiber laser operating at 1064 nm (Yb:YAG) at high repetition rate (kHz) for the removal of vandal graffiti from marble is investigated, as it is potentially suitable for cleaning of large surfaces. Indeed, this device exploits a scan system covering a wider area than that of solid state lasers, while maintaining excellent portability. Evaluation of the cleaning procedure on a selection of spray paints and felt-tip permanent markers applied on marble mock-ups is carried out with a multimodal approach (optical microscopy combined with surface pattern reconstruction, colour monitoring, Fourier Transform Infrared spectroscopy in external reflection and ATR mode, Thin Layer Chromatography, Raman spectroscopy, thermal monitoring, scanning electron microscopy). Ablation and thermal effects are observed varying the laser setting and the type of paint layer, with repetition rate showing a strong impact on the type of interaction. Overall, best cleaning procedures are achieved for the thinning of the black marker and the removal of the black spray paint. Some residues on the best results were observed, suggesting that the laser needs to be integrated with a second step of chemical cleaning. This study, focused on graffiti removal, shows that fiber laser can be a useful tool for cleaning of large monumental surfaces.Graphical

Improving Outcomes of Same-sitting Bilateral Flexible Ureteroscopy for Renal Stones in Real-world Practice—Lessons Learnt from Global Multicenter Experience of 1250 Patients

BackgroundBilateral kidney stones are commonly treated in staged procedures. ObjectiveTo evaluate outcomes after same-sitting bilateral retrograde intrarenal surgery (SSB-RIRS) for renal stones. Design, setting, and participantsData from adults who underwent bilateral RIRS in 21 centers were retrospectively reviewed (from January 2015 to June 2022). The inclusion criteria were unilateral/bilateral symptomatic bilateral stone(s) of any size/location in both kidneys and bilateral stones on follow-up with symptom/stone progression. Stone-free rate (SFR) was defined as absence of any fragment >3 mm at 3 mo. Outcome measurements and statistical analysisContinuous variables are presented as medians and 25–75th percentiles. A multivariable logistic regression analysis was performed to evaluate independent predictors of sepsis and bilateral SFR. Results and limitationsA total of 1250 patients were included. The median age was 48.0 (36–61) yr. Of the patients, 58.2% were prestented. The median stone diameter was 10 mm on both sides. Multiple stones were present in 45.3% and 47.9% of the left and right kidneys, respectively. Surgery was stopped in 6.8% of cases. The median surgical time was 75.0 (55–90) min. Complications were transient fever (10.7%), fever/infection needing prolonged stay (5.5%), sepsis (2%), and blood transfusion (1.3%). Bilateral and unilateral SFRs were 73.0% and 17.4%, respectively. Female (odds ratio [OR] 2.97, 95% confidence interval [CI] 1.18–7.49, p = 0.02), no antibiotic prophylaxis (OR 5.99, 95% CI 2.28–15.73, p < 0.001), kidney anomalies (OR 5.91, 95% CI 1.96–17.94, p < 0.001), surgical time ≥100 min (OR 2.86, 95% CI 1.12–7.31, p = 0.03) were factors associated with sepsis. Female (OR 1.88, 95% CI 1.35–2.62, p < 0.001), bilateral prestenting (OR 2.16, 95% CI 1.16–7.66, p = 0.04), and the use of high-power holmium:YAG laser (OR 1.63, 95% CI 1.14–2.34, p < 0.01) and thulium fiber laser (OR 2.50, 95% CI 1.32–4.74, p < 0.01) were predictors of bilateral SFR. Limitations were retrospective study and no cost analysis. ConclusionsSSB-RIRS is an effective treatment with an acceptable complication rate in selected patients with kidney stones. Patient summaryIn this large multicenter study, we looked at outcomes after same-sitting bilateral retrograde intrarenal surgery (SSB-RIRS) for renal stones in a large cohort. We found that SSB-RIRS was associated with acceptable morbidity and good stone clearance after a single session.

Isothermal oxidation characteristics of laser‐treated Al2O3 + Sm2SrAl2O7 composite thermal barrier coatings

AbstractA thermal barrier coating system with Al2O3 + Sm2SrAl2O7 composite top coat was developed on an Inconel 718 superalloy substrate by using an atmospheric plasma spray technique, and the coated samples are treated with an Nd:YAG fiber laser to improve the surface properties. The as‐coated and laser‐treated samples were subjected to high temperature isothermal oxidation test at 1100°C for 150 h duration. The surface of the oxidized samples showed the presence of dissociated SmAlO3, SrAl2O4, and Sm2O3. Thermally grown oxides (TGO) are found at the bond coat top coat interface of the samples. The oxidation kinetics is examined by monitoring weight gain at regular intervals. The electrochemical impedance behavior, oxidation mechanism, and TGO formation in the developed composite coatings are discussed in detail.

V04-11 THE CHALLENGING CASE OF A STAG HORN CYSTINE STONE AND A DISLOCATED URETERAL STENT IN A 18-MONTH-OLD PATIENT: VACUUM-ASSISTED MINI-PCNL AND ROBOTIC SURGERY TO THE RESCUE

You have accessJournal of UrologyCME1 Apr 2023V04-11 THE CHALLENGING CASE OF A STAG HORN CYSTINE STONE AND A DISLOCATED URETERAL STENT IN A 18-MONTH-OLD PATIENT: VACUUM-ASSISTED MINI-PCNL AND ROBOTIC SURGERY TO THE RESCUE Dario Guido Minoli, Carolina Bebi, Michele Gnech, Erika Adalgisa De Marco, Irene Paraboschi, Stefano Paolo Zanetti, Giancarlo Albo, Filippo Molinari, Emanuele Montanari, Gianantonio Manzoni, and Alfredo Berrettini Dario Guido MinoliDario Guido Minoli More articles by this author , Carolina BebiCarolina Bebi More articles by this author , Michele GnechMichele Gnech More articles by this author , Erika Adalgisa De MarcoErika Adalgisa De Marco More articles by this author , Irene ParaboschiIrene Paraboschi More articles by this author , Stefano Paolo ZanettiStefano Paolo Zanetti More articles by this author , Giancarlo AlboGiancarlo Albo More articles by this author , Filippo MolinariFilippo Molinari More articles by this author , Emanuele MontanariEmanuele Montanari More articles by this author , Gianantonio ManzoniGianantonio Manzoni More articles by this author , and Alfredo BerrettiniAlfredo Berrettini More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003252.11AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: We present the case of an 18-month-old female patient brought to the emergency department of a foreign hospital due to anuria. She was diagnosed with bilateral staghorn kidney stones and Acute Kidney Injury (AKI) (Creatinine 5.47 mg/dL) and underwent bilateral ureteral JJ stent placement. METHODS: The patient was then referred to our centre where we performed a low-dose CT scan, documenting bilateral staghorn stones and dislocation of the proximal end of the right stent in the retroperitoneum. We planned a vacuum-assisted right-sided mini-PCNL (16 Ch ClearPetra set, 12 Ch MIP Storz endoscope and 550 um Ho:YAG laser fiber) and endoscopic JJ stent removal. RESULTS: We achieved complete clearance of the urolithiasis and visualised the site of exit of the JJ stent from the ureter, 1-2 cm below the ureteropelvic junction. Unfortunately, we were unable to safely remove the device endoscopically as the proximal pigtail appeared to be stuck and very close to major vessels when pulling the distal end with endoscopic graspers under fluoroscopic vision. We reported no post-operative complications. The stone composition was cystine 100%. A week later we performed a robot-assisted procedure with a transperitoneal approach to remove the dislocated JJ stent. Removal under direct vision was possible. Few weeks later, a left mini-PCNL was performed to obtain complete stone removal. CONCLUSIONS: The use of miniaturised vacuum-assisted technologies and robotic-assisted surgery greatly aids in the management of complex cases, especially in very young children affected by cystine stones, for whom reducing invasiveness is paramount. Source of Funding: no © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e341 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Dario Guido Minoli More articles by this author Carolina Bebi More articles by this author Michele Gnech More articles by this author Erika Adalgisa De Marco More articles by this author Irene Paraboschi More articles by this author Stefano Paolo Zanetti More articles by this author Giancarlo Albo More articles by this author Filippo Molinari More articles by this author Emanuele Montanari More articles by this author Gianantonio Manzoni More articles by this author Alfredo Berrettini More articles by this author Expand All Advertisement PDF downloadLoading ...

Do Hounsfield Units have any significance in predicting intra- and postoperative outcomes in retrograde intrarenal surgery using Holmium and Thulium fiber laser? Results from the FLEXible ureteroscopy Outcomes Registry (FLEXOR).

To evaluate outcomes of flexible ureteroscopy for renal stones by comparing hard versus soft stones based on their attenuation on computed tomography (Hounsfield Units-HU). Patients were divided into two groups according to the type of laser employed [Holmium:YAG (HL) or Thulium fiber laser (TFL)]. Residual fragments (RF) were defined as > 2mm. Multivariable logistic regression analysis was performed to evaluate factors associated with RF and RF needing further intervention. 4208 patients from 20 centers were included. In whole series, age, recurrent stones, stone size, lower pole stones (LPS), and multiple stones were predictors of RF at multivariable analysis and LPS and stone size with RF requiring further treatment. HU and TFL were associated with lesser RF and RF requiring an additional treatment. In HU < 1000 stones, recurrent stones, stone size, and LPS were predictors of RF at multivariable analysis, whereas TFL was less likely associated with RF. Recurrent stones, stone size, and multiple stones were predictors of RF requiring further treatment, while LPS and TFL were associated with lesser RF requiring further treatment. In HU ≥ 1000 stones, age, stone size, multiple stones, and LPS were predictors of RF at multivariable analysis, while TFL was less likely associated with RF. Stone size and LPS were predictors of RF requiring further treatment, whereas TFL was associated with RF requiring further treatment. Stone size, LPS, and use of HL are predictors of RF after RIRS for intrarenal stones regardless of stone density. HU should be considered an important parameter in predicting SFR.

MiniPerc for treatment of renal stones between 10 and 20 mm: A comparison between high-power Holmium:YAG laser (Cyber Ho) versus Thulium Fiber Laser (Fiber Dust) generators

MiniPerc for treatment of renal stones between 10 and 20 mm: A comparison between high-power Holmium:YAG laser (Cyber Ho) versus Thulium Fiber Laser (Fiber Dust) generators

Ejaculation-sparing enucleation of the prostate with Thulium:YAG laser (ES-ThuLEP) versus Thulium Fiber Laser (ES-TFLEP): Outcomes on sexual function

Ejaculation-sparing enucleation of the prostate with Thulium:YAG laser (ES-ThuLEP) versus Thulium Fiber Laser (ES-TFLEP): Outcomes on sexual function

Understanding the ablation rate of Holmium:YAG and thulium fiber lasers. Perspectives from an in vitro study

This study sought to analyze the ablation rates of Holmium:YAG (Ho:YAG) and thulium fiber laser (TFL) under different settings combinations. Lasering was carried out by a computed spiral pattern through a stepper motor bearing a laser fiber. BegoStones were placed inside a water container and lasered therein and the ablation rate was calculated. Different combinations were tested for ~12 Watts (W) for Ho:YAG and TFL lasers. Further 25 W combination for TFL were conducted testing higher frequencies. One-hundred-one experiments were conducted. Under ~12 W, the highest ablation rate for Ho:YAG was obtained with 40 Hz/0.3 J, and Virtual Basket™ (VB) emission mode [114.35 (88.30 – 126.40) mg/min] whereas for TFL, using 40 Hz/0.3 J, and long pulse [143.40 (137.40 – 146) mg/min]. A matched-comparison for 12 Hz/1 J settings showed that TFL outperformed Ho:YAG using medium pulse [63.30 (55.30 – 81.30) vs 132.00 (115.70 – 228.60) mg/min, p=0.016] and long pulse [62.90 (51.60 – 78.90) vs 134.70 (110.60 – 149.30) mg/min, p=0.016]. In the 40 Hz/0.3 J settings, TFL outperformed Ho:YAG (p=0.034). Nonetheless, Ho:YAG with VB’s ablation rate increased [114.35 (88.30 – 126.40)], being comparable to that of TFL with medium pulse [127.5 (88.90 – 141.70)] (p=0.400). In TFL 25 W experiments, the ablation rate of 500 Hz / 0.05 J, was higher than those of 1000 Hz / 0.025 J (p=0.049). TFL ablation rate is higher than that of Ho:YAG. Moreover, the Virtual Basket™ emission mode, increased Ho:YAG ablation rates, resulting reaching similar to that of TFL in certain modalities.

Laser Efficiency and Laser Safety: Holmium YAG vs. Thulium Fiber Laser.

(1) Objective: To support the efficacy and safety of a range of thulium fiber laser (TFL) pre-set parameters for laser lithotripsy: the efficiency is compared against the Holmium:YAG (Ho:YAG) laser in the hands of juniors and experienced urologists using an in vitro ureteral model; the ureteral damage of both lasers is evaluated in an in vivo porcine model. (2) Materials and Methods: Ho:YAG laser technology and TFL technology, with a 200 µm core-diameter laser fibers in an in vitro saline ureteral model were used. Each participant performed 12 laser sessions. Each session included a 3-min lasering of stone phantoms (Begostone) with each laser technology in six different pre-settings retained from the Coloplast TFL Drive user interface pre-settings, for stone dusting: 0.5 J/10 Hz, 0.5 J/20 Hz, 0.7 J/10 Hz, 0.7 J/20 Hz, 1 J/12 Hz and 1 J/20 Hz. Both lasers were also used in three in vivo porcine models, lasering up to 20 W and 12 W in the renal pelvis and the ureter, respectively. Temperature was continuously recorded. After 3 weeks, a second look was done to verify the integrity of the ureters and kidney and an anatomopathological analysis was performed. (3) Results: Regarding laser lithotripsy efficiency, after 3 min of continuous lasering, the overall ablation rate (AR) percentage was 27% greater with the TFL technology (p < 0.0001). The energy per ablated mass [J/mg] was 24% lower when using the TFL (p < 0.0001). While junior urologists performed worse than seniors in all tests, they performed better when using the TFL than Ho:YAG technology (36% more AR and 36% fewer J/mg). In the in vivo porcine model, no urothelial damage was observed for both laser technologies, neither endoscopically during lasering, three weeks later, nor in the pathological test. (4) Conclusions: By using Coloplast TFL Drive GUI pre-set, TFL lithotripsy efficiency is higher than Ho:YAG laser, even in unexperienced hands. Concerning urothelial damage, both laser technologies with low power present no lesions.

The structure and the properties of WC-Co samples produced by SLM technology and carbon-doped prior to HIP processing

Purpose The purpose of this study is to verify how the carbon doping of the WC-Co cemented carbide (CC) affected their structure before their processing by hot isostatic pressing (HIP) technology. Design/methodology/approach The samples for this experiment were fabricated by selective laser melting technology (SLM) using a YAG fiber laser with a power of P = 40 W and a scanning speed of 83 mm/s. The subsequent carbon doping process was performed in a chamber furnace at 900 0 C for 1, 4 and 12 h. The HIP was performed at 1,390°C and pressures of 40 MPa, 80 MPa and 120 MPa. The changes induced in the structures were evaluated using X-ray diffraction and various microscopic methods. Findings X-ray diffraction analysis showed that the structure of the samples after SLM consisted of WC, W2C, Co4W2C and Co phases. As a result of the increase in the carbon content in the structure of the samples, the transition carbide W2C and structural phase Co4W2C decayed. Their decay was manifested by the coarsening of the minor alpha phase (WC), which occurred both during the carburizing process and during the subsequent processing using HIP. In the samples in which the structure was carburized prior to HIP, only the structural phases WC and Co were observed in most cases. Originality/value The results confirm that it is possible to increase the homogeneity of the CC structure and thus its applicability in practice by additional carburization of the sample structure with subsequent processing by HIP technology.

High-Speed and One-Step Deposition of a LiCoO2 Thin-Film Electrode by a High-Repetition 1064 nm Nd:YAG Fiber Laser

High-Speed and One-Step Deposition of a LiCoO₂ Thin-Film Electrode by a High-Repetition 1064 nm Nd:YAG Fiber Laser