Illumination matters Part III: Impact of light obstruction on illuminance from flexible ureteroscopes - a comparative PEARLS analysis.

PURPOSE: Artifacts from poor ureteroscopes' light design with shadowing and dark areas in the field of view have been reported. The aim was to quantify effects of light obstruction in a kidney calyx model. METHODS: We evaluated a series of contemporary flexible ureteroscopes including the Storz Flex-Xc and Flex-X2s, Olympus V3 and P7, Pusen 7.5F and 9.2F, as well as OTU Wiscope using an enclosed 3D-printed pink in vitro kidney calyx model submerged in saline, where the field of light was intentionally partially obstructed alternatively at 12, 3, 6, and 9 o'clock. A color spectrometer was used for illuminance measurements at a 45° opening position in the background of the model. RESULTS: Overall and mean background illuminance for each obstructive situation were significantly different between scopes for both 50% and 100% brightness settings (ANOVA p < 0.001). At 50% brightness setting, almost all scopes had their highest and lowest background illuminance with the 6 o'clock and 3 o'clock obstructive situation, respectively. At 100% brightness setting, these became 6 o'clock and 12 o'clock obstructive situations. Considering each obstructive situation individually, the Flex-Xc was consistently the scope with highest background illuminance and the Pusen 7.5F the lowest. Background illuminance for each obstructive situation varied significantly for each scope individually, with the greatest range of variability for Pusen 7.5F and V3. CONCLUSIONS: Illuminance performance of ureteroscopes within an obstructed calyx model differ significantly for various obstructive situations. Urologists should be aware of this to help guide their choice of ureteroscope.

A historical comparison of thulium fiber laser systems for stone lithotripsy: navigating toward safe and effective parameters.

INTRODUCTION AND OBJECTIVES: Medical device companies have introduced new TFL machines, including Soltive (Olympus, Japan), Fiber Dust (Quanta System, Italy), and TFLDrive (Coloplast, France). The primary objective of this study is to compare our initial clinical experiences with TFL using those devices. Through this historical comparison of Thulium Fiber Laser systems for stone lithotripsy, we aim to advance our understanding and approach toward achieving safe and effective TFL parameters. MATERIALS AND METHODS: The data for this comparative analysis were extracted from three distinct prospective series that were previously published, outlining our initial clinical experience with the Soltive (Olympus, Japan), FiberDust laser (Quanta System, Italy), and TFLDrive laser (Coloplast, France). Parameters such as stone size, stone density, laser-on time (LOT), and laser settings were meticulously recorded. Additionally, we assessed critical variables such as ablation speed (expressed in mm3/s) and Joules/mm3 for each lithotripsy procedure. RESULTS: A total of 149 patients were enrolled in this study. Among them, 120 patients were subjected to analysis concerning renal stones. Statistically significant differences were observed in the median (IQR) stone volume: 650 (127-6027) mm3 for TFLDrive, 1800 (682.8-2760) mm3 for Soltive, and 1125 (294-4000) mm3 for FiberDust (p: 0.007); while there were no differences regarding stone density among the groups. Significant variations were identified in median (IQR) pulse energy, frequency, and total power. The Soltive group exhibited lower energy levels (0.3 J vs. 0.6 J, p: 0.002) but significantly higher pulse frequency (100 Hz vs. 17.5 Hz, p: 0.003) and total power (24 W vs. 11W, p: 0.001) compared to the other groups. Laser-on time showed no substantial differences across all three groups. Additionally, a statistically significant difference was observed in median J/mm3, with the TFLDrive group using higher values (24 J/mm3, p: 0.001), while the Soltive group demonstrated a higher median ablation speed of 1.16 mm3/s (p: 0.001). The overall complication rate remained low for all groups, with comparable stone-free rates. CONCLUSION: By reducing pulsed frequency, we improved laser efficiency, but smaller volumes lead to decreased efficiency due to increased retropulsion and fragment movement. Further studies are needed to identify and establish the appropriate laser settings for this new technology.

Endourological Management of Ureteral Stricture in Patients with Renal Transplant: A Systematic Review of Literature.

Purpose: To analyze the utility and outcomes of available endourologic options to treat ureteral stricture after kidney transplantation (KT). Methods: A systematic review was carried out for all English language articles from 2000 to 2023 according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) standards using EMBASE, MEDLINE, SCOPUS, Google scholar, and Cochrane library. The search term combination for the string was follows: [(Ureteral stricture) OR (ureter stenosis) OR (ureteral stenosis) OR (Stricture ureter) OR (Narrowing ureter) OR (Ureter restriction) OR (ureteral restriction) OR (ureteral narrowing) OR (ureteral obstruction) OR (ureter obstruction) OR (obstructing ureter) OR (obstructive ureter) OR (narrow ureter) OR (ureteral narrow)] AND [(kidney transplant) OR (transplanted kidney) OR (transplant) OR (transplantation)] AND [(management) OR (Robotic) OR (laser) OR (stent) OR (dilatation) OR (dilation) OR (endoscopic) OR (endourological) OR (Urologic) OR (laparoscopic) OR (surgery) OR (treatment)]. Case reports, review articles, animal and laboratory studies were excluded. Risk of bias assessment was conducted using the RoB 2 and ROBINS-I tools. Results: A total of 1102 relevant articles published from 2000 to 2023 were found. After screening of titles and abstracts, a total of 19 articles were included in our systematic review. Ureteral stent/nephrostomy placement, balloon dilatation (ureteroplasty) with or without laser was used as initial approaches whereas follow-up and success rate were analyzed among other parameters. Conclusions: The management of ureteral strictures after KT is challenging and selecting the most appropriate treatment is crucial for successful outcomes. Our review suggests that, an endourologic management is a safe option with good long-term outcomes, especially in short and early strictures.

Patient Perspectives on Kidney Stone Surgery: A Content Analysis of Instagram Posts by Patients Versus Surgeons.

Background: Both clinicians and patients use social media to post about health care issues such as kidney stone disease, but their perspectives may differ. Objective: To evaluate content and themes regarding kidney stone surgery shared by patients and urologists on Instagram. Design setting and participants: A search was performed on Instagram using the term "kidney stone surgery". The first 100 posts from individuals who were clearly identified as a patient were assessed. We also assessed 100 posts from self-identified urologists. Outcome measurements and statistical analysis: A previously published system was applied as a framework for categorizing the information collected. Outcomes of interested included pain, recovery, and costs. Results and limitations: Some 71% of the patients were female and most of their posts (52%) were shared postoperatively. The most common themes covered in patient posts were the need for multiple operative sessions (45%), pain (43%), and recovery (42%). Other themes included activities of daily life (18%), return to work (11%), nervousness (16%), stent issues (31%), stent on a string (5%), diet and prevention (9%), gratitude for health care services (10%), disease recurrence (18%), and costs (10%). Some 94% of the urologists were male and their posts covered the following domains: recovery (11%), stent issues (3%), pain (1%), stent on a string (1%), gratitude for health care services (1%), and recurrence 1%. Among the posts from urologists, 79% included self-promotion and 52% covered new technology. Overall, 10% contained false information. The majority of the posts with surgical images had no clear statement regarding patient consent (97%). Conclusions: Kidney stone surgery can affect many areas of a patient's quality of life. Most of the posts shared by patients were negative. Posts shared by urologists do not reflect the same themes. Moreover, there appears to be poor adherence to European Association of Urology recommendations regarding online professional conduct. Patient summary: Many patients use social media to share their experiences of kidney stone surgery. Posts are largely related to quality-of-life issues and are mostly negative. While urologists also use social media, the content they post on professional accounts is mostly focused on new technology and career promotion.

Laser Ablation Efficiency, Laser Ablation Speed, and Laser Energy Consumption During Lithotripsy: What Are They and How Are They Defined? A Systematic Review and Proposal for a Standardized Terminology.

CONTEXT: Laser performance for lithotripsy is currently reported using units of measurement such as J/mm3, mm3/J, mm3/s, s/mm3, and mm3/min. However, there are no current standardized definitions or terminology for these metrics. This may lead to confusion when assessing and comparing different laser systems. OBJECTIVE: The primary objective was to summarize outcome values and corresponding terminology from studies on laser lithotripsy performance using stone volume in relation to time or energy. The secondary objective was to propose a standardized terminology for reporting laser performance metrics. EVIDENCE ACQUISITION: A systematic review of the literature was conducted using the search string ("j*/mm3" OR "mm3/j*" OR "mm3/s*" OR "s*/mm3" OR "mm3/min*" OR "min*/mm3" AND "lithotripsy") on Scopus, Web of Science, Embase, and PubMed databases. Study selection, data extraction, and quality assessment were performed independently by two authors. EVIDENCE SYNTHESIS: A total of 28 studies were included, covering holmium:yttrium-aluminum-garnet (Ho:YAG), MOSES, and thulium fiber laser (TFL) technologies. Laser energy consumption values reported for the studies ranged from 2.0 - 43.5 J/mm3in vitro and from 2.7 - 47.8 J/mm3in vivo, translating to laser ablation efficiency of 0.023 - 0.500 mm3/J and 0.021 - 0.370 mm3/J, respectively. Laser ablation speeds ranged from 0.3 - 8.5 mm3/s in vivo, translating to lasing time consumption of 0.12 - 3.33 s/mm3. Laser efficacy ranged from 4.35 - 51.7 mm3/min in vivo. There was high heterogeneity for the terminology used to describe laser performance for the same metrics. CONCLUSIONS: The range of laser performance metric values relating stone volume to energy or time is wide, with corresponding differing terminology. We propose a standardized terminology for future studies on laser lithotripsy, including laser ablation efficiency (mm3/J), laser ablation speed (mm3/s), and laser energy consumption (J/mm3). Laser efficacy (mm3/min) is proposed as a broader term that is based on the total operative time, encompassing the whole technique using the laser. PATIENT SUMMARY: We reviewed studies to identify the units and terms used for laser performance when treating urinary stones. The review revealed a wide range of differing units, outcomes, and terms. Therefore, we propose a standardized terminology for future studies on laser stone treatment.

Pulsed thulium:YAG laser-ready to dust all urinary stone composition types? Results from a PEARLS analysis.

PURPOSE: To evaluate whether stone dust can be obtained from all prevailing stone composition types using the novel pulsed thulium:YAG (p-Tm:YAG), including analysis of stone particle size after lithotripsy. METHODS: Human urinary stones of 7 different compositions were subjected to in vitro lithotripsy using a p-Tm:YAG laser with 270 µm silica core fibers (Thulio®, Dornier MedTech GmbH®, Wessling, Germany). A cumulative energy of 1000 J was applied to each stone using one of three laser settings: 0.1 J × 100 Hz, 0.4 J × 25 Hz and 2.0 J × 5 Hz (average power 10 W). After lithotripsy, larger remnant fragments were separated from stone dust using a previously described method depending on the floating ability of dust particles. Fragments and dust samples were then passed through laboratory sieves to evaluate stone particle count according to a semiquantitative analysis relying on a previous definition of stone dust (i.e., stone particles ≤ 250 µm). RESULTS: The p-Tm:YAG laser was able to produce stone dust from lithotripsy up to measured smallest mesh size of 63 µm in all seven stone composition types. Notably, all dust samples from all seven stone types and with all three laser settings had high counts of particles in the size range agreeing with the definition stone dust, i.e., ≤ 250 µm. CONCLUSION: This is the first study in the literature proving the p-Tm:YAG laser capable of dusting all prevailing human urinary stone compositions, with production of dust particles ≤ 250 µm. These findings are pivotal for the broader future implementation of the p-Tm:YAG in clinical routine.

Living donor-gifted allograft lithiasis: surgical experience after bench surgery stone removal and follow-up.

This study presents the surgical experience and long-term outcomes of living donor kidney transplantations involving asymptomatic kidney stones, using ex vivo flexible ureterorenoscopy (f-URS) during bench surgery for stone removal. Out of 1743 living kidney donors assessed between January 2012 and October 2022, 18 (1%) were diagnosed with urolithiasis. Among them, 12 donors were rejected, and 6 were accepted for kidney donation. Stone removal was successfully performed using f-URS during bench surgery, with no immediate complications or acute rejections observed. The study analyzed six living kidney transplants, of which 4 (67%) donors and three recipients were female, and 4 (67%) donors were blood-related to the recipient. The median age for donors and recipients was 57.5 and 51.5 years, respectively. The stones, primarily located in the lower calyx, had a median size of 6 mm. The median cold ischemia time during surgery was 41.6 min, and ex vivo f-URS ensured complete stone removal in all cases. After a median follow-up of 120 months, the remaining grafts were functioning well, and no urinary stone recurrence was observed in either the recipients or living donors. The findings suggest that bench f-URS is a safe approach for managing urinary stones in kidney grafts, providing good functional outcomes without stone recurrence in selected cases.

Retrograde intrarenal surgery for stones associated with renal anomalies: caliceal diverticulum, horseshoe kidney, medullary sponge kidney, megacalycosis, pelvic kidney, uretero-pelvic junction obstruction.

PURPOSE OF REVIEW: Nowadays, due to the increase of imaging diagnosis, we identify easily renal anomalies, and we can choose between a wide range of armamentarium to treat symptomatic stones in those challenging cases. However, there is a lack of evidence and consensus on its use. The aim of this narrative review is to collect all the available data about safety and efficacity of retrograde intrarenal surgery (RIRS) in the treatment of kidney stones associated to a renal anomaly. RECENT FINDINGS: Renal anomalies are uncommon findings and even more if it has to be associated with renal stones. After a literature review of the past 2 years, there are a small number of studies that compare the outcomes in patients who have been treated with minimally invasive modalities and they are mainly focus on RIRS. SUMMARY: It is of extreme importance to know the advances on the stone treatment in anomalous kidneys. With the development of new laser technologies, RIRS is becoming a more interesting technique with high success rate and safety. Further studies are needed to make an accurate statement about the adequate surgical technique for each renal anomaly and also, clinical trials using new laser technologies.

Robotic Retrograde Intrarenal Surgery: A Journey from "Back to the Future".

The introduction of robotics has revolutionized surgery. Robotic platforms have also recently been introduced in clinical practice specifically for flexible ureteroscopy. In this paper, we look at the robotic platforms currently available for flexible ureteroscopy, describing their advantages and limitations. The following robotic platforms are discussed: Roboflex Avicenna®, EasyUretero®, and ILY® robot. Finally, potential future advancements in this field are presented.

Risk of Sepsis in Retrograde Intrarenal Surgery: A Systematic Review of the Literature.

Context: Nowadays, urolithiasis has become a highly prevalent disease. Recent studies indicate that retrograde intrarenal surgery (RIRS) is becoming more popular among surgical treatments due to the preference of patients and providers. This minimally invasive procedure results in high stone-free rates and relatively low morbidity; however, complications resulting from infection can still occur, including acute urinary tract infection, systemic inflammatory response syndrome, and sepsis. Objective: To identify the independent risk factors for sepsis following RIRS, as well as general risk factors that may contribute to this life-threatening complication in the pre- and intraoperative periods. Evidence acquisition: A literature review was conducted in April 2020 using the Medline, Scopus, and Cochrane databases. We searched the references of included papers. Evidence synthesis: We screened 2306 manuscripts and selected 13 for inclusion. The sepsis rate ranged from 0.5% to 11.1%, and the septic shock rate ranged from 0.3% to 4.6%. All selected studies mentioned risks for sepsis and/or infective complications (including sepsis), but only four of them addressed independent risks for urosepsis. These independent risk factors were stone size, high irrigation pressure, prolonged stent dwelling time (>30 d), sepsis as an indication for stent insertion, female gender, positive intraoperative bladder urine culture, longer surgical time, and diabetes mellitus. Conclusions: RIRS is associated with a low sepsis rate, according to the latest evidence. However, given that this is a serious life-threatening complication, knowing its potential risk factors is extremely important. Patient summary: In this report, we looked at the outcome of sepsis after planned retrograde intrarenal surgery for stone disease in patients with and without comorbidities. This information may be useful for colleagues in their daily practice.

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.

Moses and Moses 2.0 for Laser Lithotripsy: Expectations vs. Reality.

Moses technology was born with the aim of controlling the Moses effect present in every single Ho:YAG laser lithotripsy. The capacity to divide the energy pulse into two sub-pulses gained popularity due to the fact that most of the energy would be delivered in the second pulse. However, is this pulse modulation technique really better for endocorporeal laser lithoripsy? A review of the literature was performed and all relevant clinical trials of Moses 1.0 and 2.0, as well as the lab studies of Moses 2.0 carried out up to June 2022 were selected. The search came back with 11 clinical experiences (10 full-text clinical trials and one peer-reviewed abstract) with Moses 1.0 and Moses 2.0, and three laboratory studies (peer-reviewed abstracts) with Moses 2.0 only. The clinical experiences confirmed that the MT (1.0) has a shorter lasing time but lower laser efficacy, because it consumes more J/mm3 when compared with the LP Ho:YAG laser (35 W). This gain in lasing time did not provide enough savings for the medical center. Additionally, in most comparative studies of MT (1.0) vs. the regular mode of the HP Ho:YAG laser, the MT did not have a significant different lasing time, operative time or stone-free rate. Clinical trials with Moses 2.0 are lacking. From what has been published until now, the use of higher frequencies (up to 120 Hz) consumes more total energy and J/mm3 than Moses 1.0 for similar stone-free rates. Given the current evidence that we have, there are no high-quality studies that support the use of HP Ho:YAG lasers with MT over other lasers, such as LP Ho:YAG lasers or TFL lasers.

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.

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.

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.

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.

Metabolic evaluation: is there really a future?

PURPOSE OF REVIEW: To confirm the need for a metabolic evaluation in stone formers based on the latest information published in the last 24 months and in the current 2022 American and European urological guidelines. RECENT FINDINGS: Recent studies suggest that urolithiasis prevalence has been increasing since 1990. Along with it, metabolic abnormalities that contribute to the development of kidney stones are also increasing, such as hyperuricosuria, hyperoxaluria, hypocitraturia, hypomagnesuria, hypocalciuria, hypophosphaturia, and hyperuricemia. Those abnormalities can only be detected through a metabolic evaluation in patients with stone disease. SUMMARY: It is important for us, urologists, to have in mind the actual stone prevalence worldwide. As part of our initial evaluation of the patient with urolithiasis, we must not forget to perform the basic metabolic analysis and, according to the patient's risk classification, continue with a deep metabolic analysis. This extensive analysis includes blood and urine tests. The urinalysis covers 24-h urinalysis, and it would be accurate to also have an early fresh urine analysis. Moreover, identifying the stone type is intimately correlated with the search for other metabolic parameters.

Thulium fiber laser pre-settings during ureterorenoscopy: Twitter's experts' recommendations.

INTRODUCTION: Thulium fiber laser (TFL) is a novel laser in the field of urology. There is no consensus for optimal parameters. As most urologists use social media, being Twitter the platform with the most dissemination in healthcare, we aim to review the preferred TFL settings chosen by the experts and, to evaluate their pros and cons. MATERIALS AND METHODS: A Twitter review was performed from November 2019 (firsts TFL experiences in urology) until October 2021 using the hashtags: "thuliumfiber", "ThuliumFiberLaser", "TFL" "soltive", "fiberdust", "OlympusUrology", "quanta_system", "IPG_Photonics", "rocamed". Only board-certified urologists were considered. The "tweets" selected include information about TFL preferred settings for stone lithotripsy and tissue ablation. Additionally, we also seek information regarding laser technique, fiber size, laser time, stone type and equipment. RESULTS: A total of 42 opinions were identified. The 23 endourologists have a median of 2.298 followers (range 202-10.000). Most comments were about TFL settings for kidney stone dusting (61%). There was a significant difference (p < 0.05) for kidney stone dusting settings (dusting, frequency, and power) between endourologists. Only 24% reported their fiber size, 4 reported the stone composition and 2 endourologists mentioned their type of ureteroscope. There was no discussion about technique used (burst or continuous) nor equipment. Surgery time was reported 3 times. CONCLUSION: There is no consensus in TFL pre-settings. When a pre-setting is proposed, it should also recommend technique to be used. Settings are personal and related to multiple factors, such as training, technique, equipment and fiber size.