Initial clinical experience with the thulium fiber laser from Quanta System: First 50 reported cases.

OBJECTIVE: To evaluate the new thulium fiber laser (TFL) from Quanta System (Fiber Dust™) in terms of efficiency, safety, and laser settings in laser lithotripsy during retrograde intrarenal surgery (RIRS). METHODS: A prospective study of the first 50 patients with ureteral and renal stones who underwent RIRS using the new Fiber Dust (TFL from Quanta System, Italy) was performed in a single center. 200 µm and 150 µm laser fibers were used. Stone size, stone density, laser-on time (LOT) and laser settings were recorded. We also assessed the ablation speed (mm3/s), Joules/mm3 and laser power (W) values for each procedure. RESULTS: A total of 50 patients were analyzed. The median (IQR) age was 54.5 (43-65) years old. Median (IQR) stone volume was 347 (147-1800) mm3 and 1125 (294-4000) mm3 for ureteral and renal stones, respectively. Median (IQR) stone density was 900 (400-1500) HU for ureteral stones and 950 (725-1125) HU for renal stones. Median (IQR) pulse energy was 0.6 (0.5-1) J and 0.6 (0.5-0.9) J for ureteral and renal stones, respectively. Median (IQR) frequency for ureteral stones was 10 (10-20) Hz and for renal stones, 15 (10-20) Hz. All procedures used short pulse. There were no statistically significant differences in pulse energy, frequency, laser power or LOT in both groups. The median (IQR) J/mm3 was 8.7 (4.8-65.2) for ureteral stones vs 14.3 (7.8-24.7) for renal stones. The median (IQR) ablation rate was 0.3 (0.2-1.3) mm3/s for ureteral stones vs 0.7 (0.4-1.2) mm3/s for renal stones. Neither of those results reached the significance threshold. Overall complication rate was low in both groups, and none was related to TFL. CONCLUSION: According to our results, the new TFL laser is safe and effective for lithotripsy during RIRS, using low pulse energy and low pulse frequency.

Glossary of pre-settings given by laser companies: no consensus!

INTRODUCTION: Since the construction of the first laser, many companies around the world have contributed to the development of new lasers technologies. To be user-friendly, some companies have developed a pre-setting mode in their laser devices. We aimed to review and compare all laser companies' pre-settings (PS) already established in the market. MATERIALS AND METHODS: An online search of holmium:YAG (Ho:YAG) and thulium fiber laser (TFL) devices was carried out. Manual and PS mode, pulse width and pulse modulation technology data were collected. The PS parameters were collected directly from the brochure devices or by asking the companies consulting agents. RESULTS: Thirty-nine laser devices were analyzed (33 Ho:YAG and 6 TFL). The power range varies from 15 to 152 W and 35 W to 60 W for Ho:YAG and TFL, respectively. PS are present in 66% of Ho:YAG lasers and the 33% of TFL. Long-pulse modes can be modified in 12 Ho:YAG and 1 TFL lasers. The median (IQR) PS for dusting stones with Ho:YAG laser is 0.4 J (0.2-1), 21.5 Hz (5-120), and 10 W (1.5-28) for energy, frequency and power, respectively; for Ho:YAG fragmentation is 0.8 J (0.3-5), 10 (3-15) Hz and 5 (1.5-50) W for energy, frequency, and power, respectively; and for popcorn is 0.8 J (0.4-1.2), 10 Hz (6-15) and 5 W (4-18) for energy, frequency, and power, respectively. Dusting and fragmentation mode of Rocamed MH01 and EMS LaserClast 35 are programmed according to the stone type. Most of these settings do not depend on the size of the fiber being used nor the location and type of stone. For TFL, the pre-sets are divided in bladder stone, dusting, fine dusting, fragmentation, and ureteral stone. CONCLUSION: There is a huge variability regarding pre-sets offered by companies because there is no consensus. Pre-sets should provide a range to work efficacy and safety.

Differences in Quality of Life between German and Dutch Patients with Prostate Cancer Treated with Robot-assisted Radical Prostatectomy: Implications for International Multicenter Randomized Controlled Trials.

BACKGROUND: As a local treatment for prostate cancer (PCa), robot-assisted radical prostatectomy (RARP) may have a quality of life (QoL) benefit over open surgery. Recent analyses revealed substantial between-country differences in the function and symptom scale scores for the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30), which is typically used to assess patient-reported QoL. Such differences could have implications for multinational studies in PCa. OBJECTIVE: To examine whether nationality is significantly associated with patient-reported QoL. DESIGN, SETTING, AND PARTICIPANTS: The study cohort comprised Dutch and German patients with PCa treated with RARP in a single high-volume prostate center from 2006 to 2018. Analyses were restricted to patients who were preoperatively continent with at least one follow-up time point. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: QoL was measured in terms of the global Quality of Life (QL) scale score and the overall summary score for the EORTC QLQ-C30. Linear mixed models for repeated-measures multivariable analyses (MVAs) were used to examine the association between nationality and both the global QL score and the summary score. MVAs were further adjusted for QLQ-C30 baseline values, age, Charlson comorbidity index, preoperative prostate-specific antigen, surgical expertise, pathological tumor and nodal stage, Gleason grade, degree of nerve-sparing, surgical margin status, 30-d Clavien-Dindo grade complications, urinary continence recovery, and biochemical recurrence/postoperative radiotherapy. RESULTS AND LIMITATIONS: For Dutch (n = 1938) versus German (n = 6410) men, the mean baseline scores were 82.8 versus 71.9 for the global QL scale score and 93.4 versus 89.7 for the QLQ-C30 summary score. Urinary continence recovery (QL: +8.9, 95% confidence interval [CI] 8.1-9.8; p < 0001) and Dutch nationality (QL: +6.9, 95% CI 6.1-7.6; p < 0001) were the strongest positive contributors to the global QL and summary scores, respectively. The main limitation is the retrospective study design. In addition, our Dutch cohort may not be representative of the general Dutch population and reporting bias cannot be ruled out. CONCLUSIONS: Our findings provide observational evidence under specific conditions involving the same setting for patients of two different nationalities suggesting that cross-national patient-reported QoL differences appear to be real and may need to be taken into consideration in multinational studies. PATIENT SUMMARY: We observed differences in the quality-of-life scores reported by Dutch and German patients with prostate cancer after they underwent robot-assisted removal of the prostate. These findings should be taken into consideration in cross-national studies.

Stiff Guidewires in Endourology: What Is Stiffness?

Introduction: The aim of this study is to perform a literature review of stiff guidewires used in urology and to investigate if there is an official definition for stiffness (shaft rigidity) of wires. Materials and Methods: A literature search was performed for all English language articles in MEDLINE and Scopus databases, Google Scholar, and the official websites of international companies. Guidewires from different companies were included. Results: We analyzed 14 different stiff guidewires from the companies, Boston Scientific, Coloplast, Cook Medical, Olympus, Terumo, Rocamed, and Bard Urological, according to their characteristics. We found no concrete data regarding their stiffness on the official websites. In addition, there were a few published studies about the Amplatz Super Stiff guidewire (Boston Scientific), ZIPwire™ Stiff Nitinol Hydrophilic guidewire (Boston Scientific), HiWire Stiff Nitinol Core Wire Guide (Cook Medical), Amplatz Fixed Core Wire Guide (Cook Medical), and NiCore™ Nitinol Guidewire-Stiff (Bard Urological), whereas there were no available data for the majority of stiff guidewires. Conclusions: Stiff guidewires are listed in catalogs of companies without any information regarding their classification. They are only divided into stiff and standard versions without knowing the differences between them. The companies and their manufacturers should adopt a common method to calculate and define the stiffness of each guidewire.

Real Time Intrarenal Pressure Control during Flexible Ureterorrenscopy Using a Vascular PressureWire: Pilot Study.

(1) Introduction: To evaluate the feasibility of measuring the intrapelvic pressure (IPP) during flexible ureterorenoscopy (f-URS) with a PressureWire and to optimize safety by assessing IPP during surgery. (2) Methods: Patients undergoing f-URS for different treatments were recruited. A PressureWire (0.014", St. Jude Medical, Little Canada, MN, USA) was placed into the renal cavities to measure IPP. Gravity irrigation at 40 cmH2O over the patient and a hand-assisted irrigation system were used. Pressures were monitored in real time and recorded for analysis. Fluid balance and postoperative urinary tract infection (UTI) were documented. (3) Results: Twenty patients undergoing f-URS were included with successful IPP monitoring. The median baseline IPP was 13.6 (6.8-47.6) cmH2O. After the placement of the UAS, the median IPP was 17 (8-44.6) cmH2O. With irrigation pressure set at 40 cmH2O without forced irrigation, the median IPP was 34 (19-81.6) cmH2O. Median IPP during laser lithotripsy, with and without the use of on-demand forced irrigation, was 61.2 (27.2-149.5) cmH2O. The maximum pressure peaks recorded during forced irrigation ranged from 54.4 to 236.6 cmH2O. After the surgery, 3 patients (15%) presented UTI; 2 of them had a positive preoperative urine culture, previously treated, and a positive fluid balance observed after the surgery. (4) Conclusion: Based on our experience, continuous monitoring of IPP with a wire is easy to reproduce, effective, and safe. In addition, it allows us to identify and avoid high IPPs, which may affect surgery-related complications.

Thulium Fiber Laser's Dust for Stone Composition Analysis: Is It Enough? A Pilot Study.

Introduction: We aimed to evaluate if the biochemical composition of urinary stones can be determined by analyzing the stone dust only, and whether a photo taken during the surgery could be useful for completing the morpho-constitutional analysis. Materials and Methods: Twenty patients went through a retrograde intrarenal surgery for renal stone treatment with thulium fiber laser (Fiber Dust; Quanta, 2020) using 150 µm silica core laser fibers. After laser lithotripsy, residual fragments (RF) were removed with a basket (ZeroTip; Boston Scientific) and spontaneously floating stones particles were considered stone dust and were aspirated through the working channel. Pairs of RF and stone dust were labeled and sent to analysis by scanning electron microscopy and Fourier transform infrared spectroscopy. Photos of the stone (surface and section) were taken from videos recorded during the surgery. Results: A total of 20 patients were included in this study. Mean age was 49.8 years with metabolic and genetic disorders. Mean stone volume was 750 mm3 for ureteral stones and 2334 mm3 for renal stones. Mean stone density was 1187 HU. Positive urine culture was found in 25% patients. In 2/20 (10%), the biochemistry differed only in the relative proportions of each constituent, while in 5/20 (25%), only one component was missing. Laser crystalline conversion was found in 3/20 (15%). Whewellite and weddellite layers were found in photos, thus adding missing information from dust stone analysis. Conclusion: By analyzing aspirated dust through the ureteroscope's working channel with physical techniques, we can understand the lithogenic process of the urinary stone, without needing to analyze the stone fragment. Morphologic analysis, given by a proper stone picture, adds missing information in specific cases.

Thermal Injury and Laser Efficiency with Holmium YAG and Thulium Fiber Laser-An In Vitro Study.

Objective: To evaluate using an inanimate model the thermal injury and laser efficiency on high frequency, high energy, and its combination in hands of junior and experienced urologists during holmium YAG (Ho:YAG) and Thulium fiber laser (TFL) lithotripsy. Methods: A Cyber: Ho 150 WTM and Fiber Dust TFL (Quanta System) with 200 µm core-diameter laser fibers (LF) were used in a saline in vitro ureteral model. Each participant (five junior and five experienced urologists) performed 32 sessions of 5-minute lasering (125 mm3 phantom BegoStones™), comparing four modes (3 J/5 Hz [1.5 W], 0.3 J/20 Hz [6 W], 1.2 J/5 Hz [6 W], and 1.2 J/20 Hz [24 W]). Transparent tip and cleaved LF, and digital and fiberoptic ureteroscopes were also compared. Ureteral damage was classified in a scale (0-5) according to the burns and holes seen in the ureteral model's surface. Results: High-power (HP) setting (24 W) was associated with higher delivered energy and higher ablation rates (ARs) in both lasers (p < 0.001). For the same power setting (6 W), there was no difference in delivered energy or stone ARs. Regardless the settings, a higher AR was observed with TFL than with Ho:YAG (0.5Δ mg/s ± 0.33 vs 0.39 Δmg/s ± 0.31, p = 0.002) laser. Higher mean AR was found with cleaved tip vs transparent tip (p = 0.03) in TFL. For both lasers, higher ureteral damage was observed in the 24 W group (p = 0.006) and in the junior urologists (p = 0.03). Between 6 W groups, different types of lesions were found and junior urologist have more lesions when high frequency was used, for both Ho:YAG (p = 0.05) and TFL (p = 0.04). Conclusion: More stone ARs and reduced operative time are observed in HP settings; however, more ureteral thermic-related damage is produced. When comparing the same power, higher energy or frequency does not modify the AR. Nonetheless, more ureteral thermic-related thermal damage is observed in high-frequency settings in unexperienced hands.