Comparison of holmium:yttrium-aluminium-garnet (YAG), thulium fiber laser, and pulsed thulium:YAG lasers on soft tissue: an ex vivo study.

OBJECTIVES: To assess laser-tissue interactions through ablation, coagulation, and carbonisation characteristics in a non-perfused porcine kidney model between three pulsed lasers: holmium (Ho): yttrium-aluminium-garnet (YAG), thulium fiber laser (TFL), and pulsed thulium (p-Tm):YAG. MATERIALS AND METHODS: A 150-W Ho:YAG, a 60-W TFL, and a 100-W p-Tm:YAG lasers were compared. The laser settings that can be set identically between the three lasers and be clinically relevant for prostate laser enucleation were identified and used on fresh, unfrozen porcine kidneys. Laser incisions were performed using stripped laser fibers of 365 and 550 µm, set at distances of 0 and 1 mm from the tissue surface at a constant speed of 2 mm/s. Histological analysis evaluated shape, depth, width of the incision, axial coagulation depth, and presence of carbonisation. RESULTS: Incision depths, widths, and coagulation zones were greater with Ho:YAG and p-Tm:YAG lasers than TFL. Although no carbonisation was found with the Ho:YAG and p-Tm:YAG lasers, it was common with TFL, especially at high frequencies. The shapes of the incisions and coagulation zones were more regular and homogeneous with the p-Tm:YAG laser and TFL than with Ho:YAG laser. Regardless of the laser used, short pulse durations resulted in deeper incisions than long pulse durations. Concerning the distance, we found that to be effective, TFL had to be used in contact with the tissue. Finally, 365-µm fibers resulted in deeper incisions, while 550-µm fibers led to wider incisions and larger coagulation zones. CONCLUSION: Histological analysis revealed greater tissue penetration with the p-Tm:YAG laser compared to the TFL, while remaining less than with Ho:YAG. Its coagulation properties seem interesting insofar as it provides homogeneous coagulation without carbonisation, while incisions remained uniform without tissue laceration. Thus, the p-Tm:YAG laser appears to be an effective alternative to Ho:YAG and TFL lasers in prostate surgery.

Comprehensive Approaches to Urolithiasis in Renal Transplants: A Narrative Review.

This review addresses the management of urolithiasis in renal transplant recipients, a notably vulnerable group due to the unique anatomical and physiological alterations of the transplanted organ. The prevalence of nephrolithiasis in these patients varies between 0.1% and 6.3%, with a significant impact on graft longevity and function. Surgical access complications due to the renal graft's position on the iliac vessels and the variety of urinary anastomoses complicate the treatment approaches. This study evaluates the effectiveness and outcomes of percutaneous nephrolithotomy (PCNL) and ureteroscopy (URS), two primary minimally invasive strategies for managing graft stones. Through a narrative review using the PubMed and EMBASE databases, it was found that PCNL offers high stone-free rates especially beneficial for large stones, whereas URS provides a less invasive option with a lower risk of complications for small stones. Both techniques require tailored approaches based on stone composition-mostly calcium oxalate-and specific patient anatomical factors. This review underscores the importance of early diagnosis, appropriate treatment selection, and continuous post-treatment monitoring to mitigate risks and promote long-term renal function in transplant recipients.

Thulium Fiber Versus Holmium:Yttrium-aluminum-garnet Laser for Endoscopic Enucleation of the Prostate: A Systematic Review and Meta-analysis.

BACKGROUND AND OBJECTIVE: Thulium fiber laser (TFL) emerged as a competitor of holmium:yttrium-aluminum-garnet (Ho:YAG) laser for anatomic enucleation of the prostate (AEEP) in men with lower urinary tract symptoms (LUTS) related to benign prostatic obstruction (BPO). The aim was to compare the surgical outcomes of Ho:YAG and TFL for AEEP. METHODS: A literature search was conducted to identify reports published from inception until January 2024. The Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were followed to identify eligible studies. The coprimary outcomes were the postoperative International Prostate Symptom Score (IPSS), IPSS-Quality of Life (IPSS-QoL), and peak urinary flow (Qmax). KEY FINDINGS AND LIMITATIONS: Five studies met our inclusion criteria, and data from 1287 and 1555 patients who underwent AEEP with Ho:YAG (holmium laser enucleation of the prostate [HoLEP]) and TFL (thulium fiber laser enucleation of the prostate [ThuFLEP]), respectively, were reviewed. ThuFLEP was associated with a better IPSS at 3 mo even if the difference was not clinically significant (mean difference [MD] 0.59, 95% confidence interval [CI]: 0.29-0.88; p < 0.001). No difference was found for IPSS at 6-12 mo (p = 0.9), and IPSS-QoL at 3 mo (p = 0.9) and 6-12 mo (p = 0.2). HoLEP was associated with a better Qmax at 3 mo (MD 1.41 ml/s, 95% CI: 0.51-2.30; p = 0.002) and ThuFLEP at 6-12 mo (MD -2.61 ml/s, 95% CI: -4.68 to 0.59; p = 0.01), but the differences were not clinically significant. No difference was found in the major (p = 0.3) and overall (p = 0.3) complication rates. HoLEP was associated with shorter enucleation (MD -11.86, 95% CI: -22.36 to 1.36; p = 0.03) but not total operative time (p = 0.5). CONCLUSIONS AND CLINICAL IMPLICATIONS: The present review provides the most updated evidence on the impact of Ho:YAG and TFL in AEEP, demonstrating that these two energy sources are effective in relieving bothersome LUTS in men with BPO. PATIENT SUMMARY: Thulium fiber laser is a new energy source that can be used safely for performing endoscopic enucleation of the prostate in men with bothersome symptoms associated with benign prostatic enlargement.

Arterial pseudoaneurysm: a rare complication following laser lithotripsy-case series and literature review.

OBJECTIVE: To perform a comprehensive narrative review that will examine the risk factors and treatment outcomes of arterial pseudoaneurysm following laser flexible ureteroscopy (F-URS). METHODS: A retrospective case series and a review of literature was performed. Clinical records from three patients treated for postoperative arterial pseudoaneurysm from January of 2021 to November 2023 were identified. A comprehensive literature review was also performed. The MEDLINE and Scopus databases were searched. The analysis was made by a narrative synthesis. RESULTS: Three cases of postoperative arterial pseudoaneurysm were included, one from our center, one from Dubai, UAE, and one from Barcelona. The literature review identified six case reports, two after endocorporeal laser lithotripsy with thulium fiber laser (TFL) and four with Ho:YAG laser. All cases, from our series and literature review, presented with macroscopic hematuria and used high-power laser settings. All cases were treated by selective embolization. CONCLUSION: Ho:YAG or TFL lasers are both capable of causing arterial pseudoaneurysms following F-URS if high-power settings are used. Selective artery embolization continues to be the treatment of choice with good outcomes.

Ureteroscopic management in cystinuric patients: long-term results from a tertiary care referral center.

OBJECTIVE: To evaluate long-term surgical and functional outcomes of cystinuric patients exclusively treated with Ureteroscopy (URS). METHODS: Data from patients treated for cystine stones at a single academic center were retrospectively analyzed. The management protocol consisted of (i) treating symptomatic or > 7 mm stones, (ii) multi-staged URS for voluminous stones, (iii) referring patients to a dedicated nephrological clinic. The eGFR was calculated according to the MDRD formula. CKD category was assessed according to the NKF classification. Relevant CKD was defined as CKD category ≥ 3a. Descriptive statistics were used to analyze the cohort data. RESULTS: Data from 46 cystinuric patients treated with 332 URS were available. Median age at diagnosis and at first URS in our center were 18 and 32 years, respectively. Median follow-up was 101 months. Median number of URS and recurrences per patient were 6 and 2, respectively. The median interval between the first and the last available creatinine level was 64 months. Median first and last eGFR were 72 and 74 mL/min, respectively. Overall, 83% of patients had stable or improved renal function within the study period. Ureteral stricture occurred in 3 (6.5%) patients. CONCLUSIONS: Cystinuria requires intensive endoscopic management. Most patients treated with URS have stable or improved renal function within a long-term follow-up. CKD is a not neglectable event that potentially occurs at an early stage of life. Current findings should be considered for the surgical management of cystinuric patients.

Ureteral stents: What your eyes can't see! An in vitro study.

OBJECTIVES: To characterize and compare in vitro the surfaces of ureteral stents (STENTS) before utilization. METHODS: Our in vitro experiment included six unused STENTS models: three double-pigtail with side orifices (ImaJin and Stenostent [Coloplast©,France], TriaSoft [BostonScientific©,USA]), two double-pigtail without side orifice (Vortek-TumorStent [Coloplast©,France], Urosoft-TumorStent [Bard-Angiomed©,Germany]) and one single-pigtail (J-Fil [Rocamed©,Monaco]). STENTS were made of polyurethane except for ImaJin (silicone). For all STENTS, four parts of the stent were specifically analyzed under high-resolution scanning electron microscopy (HR-SEM,FEI-XL40 [Philips©,France]): surface core, lateral orifice, ureteral loop, and black marking surface. Each experiment was repeated with three different samples from three different stents. STENTS analysis included multiple imperfection searches, defined as irregularities>10µm. RESULTS: All STENTS presented imperfections with no discernible differences. Imperfections were mainly located on the stent loop and on the lateral orifice. For STENTS without side orifice (J-Fil, Urosoft) imperfections were also reported, on the beveled cut as well as the distal loop orifice. Marking surfaces examinations found defects in the Urosoft and imperfections in the ImaJin and Stenostent. The Triasoft presented a better smoothness on marking surfaces compared to other STENTS. Additional matter was reported on the loop distal orifice for J-Fil and ImaJin but all STENTS presented irregular cross-sectional aeras. CONCLUSION: All ureteral stents are not perfectly smooth even before utilization. Imperfections were noticed regardless to stent composition or shape, and could play a role in the incrustation phenomenon, is association with inner irregularities, infection, and urine composition. Both manufacturing and material could have an impact on the stent external surface's smoothness.

Is "Kidney Stone Calculator" efficient in predicting ureteroscopic lithotripsy duration? A holmium:YAG and thulium fiber lasers comparative analysis.

PURPOSE: This study aimed to evaluate the ability of Kidney Stone Calculator (KSC), a flexible ureteroscopy surgical planning software, to predict the lithotripsy duration with both holmium:YAG (Ho:YAG) and thulium fiber laser (TFL). METHODS: A multicenter prospective study was conducted from January 2020 to April 2023. Patients with kidney or ureteral stones confirmed at non-contrast computed tomography and treated by flexible ureteroscopy with laser lithotripsy were enrolled. "Kidney Stone Calculator" provided stone volume and subsequent lithotripsy duration estimation using three-dimensional segmentation of the stone on computed tomography and the graphical user interface for laser settings. The primary endpoint was the quantitative and qualitative comparison between estimated and effective lithotripsy durations. Secondary endpoints included subgroup analysis (Ho:YAG-TFL) of differences between estimated and effective lithotripsy durations and intraoperative outcomes. Multivariate analysis assessed the association between pre- and intraoperative variables and these differences according to laser source. RESULTS: 89 patients were included in this study, 43 and 46 in Ho:YAG and TFL groups, respectively. No significant difference was found between estimated and effective lithotripsy durations (27.37 vs 28.36 min, p = 0.43) with a significant correlation (r = + 0.89, p < 0.001). Among groups, this difference did not differ (p = 0.68 and 0.07, respectively), with a higher correlation between estimated and effective lithotripsy durations for TFL compared to Ho:YAG (r = + 0.95, p < 0.001 vs r = + 0.81, p < 0.001, respectively). At multivariate analysis, the difference was correlated with preoperative (volume > 2000 mm3 (Ho:YAG), 500-750 mm3 SV and calyceal diverticulum (TFL)), operative (fragmentation setting (p > 0.001), and basket utilization (p = 0.05) (Ho:YAG)) variables. CONCLUSION: KSC is a reliable tool for predicting the lithotripsy duration estimation during flexible ureteroscopy for both Ho:YAG and TFL. However, some variables not including laser source may lead to underestimating this estimation.

Overactive bladder negatively affects erectile function and promotes premature ejaculation: findings from large representative population-level study.

PURPOSE: The effect of overactive bladder (OAB) on sexual health has been evaluated extensively for women but much less for men. Therefore, the aim of this study was to evaluate the relationship between OAB and men's sexual activity and the effect of OAB on erectile dysfunction (ED) and premature ejaculation (PE) in a large representative cohort of men at the population level. METHODS: This study was based on computer-assisted web interviews that used validated questionnaires. The most recent census and the sample size estimation calculations were employed to produce a population-representative pool. RESULTS: The study included 3001 men, representative of the population in terms of age and place of residence. The frequency of sexual intercourse was higher for respondents without OAB symptoms compared with persons who had OAB (p = 0.001), but there was no association between OAB symptoms and number of sexual partners (p = 0.754). Regression models did not confirm the effect of OAB on sexual activity (odds ratio 0.993, CI 0.974-1.013, p = 0.511). Both ED and PE were more prevalent in respondents with OAB symptoms compared with persons who lacked those symptoms (p < 0.001). Importantly, the effect of OAB on ED or PE was independent of age, comorbidities, and lifestyle habits (regression coefficients of 0.13 and 0.158 for ED and PE, respectively). CONCLUSION: Overactive bladder did not significantly affect men's sexual activity, but it significantly correlated with ED and PE. Our results suggest a need in daily clinical practice to screen for OAB symptoms for persons who report ED or PE.

Comparison of European and American Guidelines for Upper Tract Urothelial Carcinoma: How Are They different?

Urothelial carcinoma (UC) affecting the urinary tract is recognized as one of the prevalent types of cancer, ranking fifth in terms of incidence. However, it is important to note that upper tract urothelial carcinoma (UTUC), in comparison to bladder cancer, is relatively uncommon and represents a minority of UC cases, accounting for ∼5% to 10%. It is worth emphasizing that as much as 60% of UTUC cases are invasive at the time of diagnosis, in contrast to 25% of bladder cancer cases. These statistics highlight the urgent need for well-designed, multidisciplinary strategies to guide optimal management for this vulnerable patient population, aiming to control treatment variability and minimize the risks associated with undertreatment and overtreatment. Methods: In this study, we present a comparative analysis of the contemporary guidelines on UTUC management from the European Association of Urology (EAU) and the American Urological Association/Society of Urologic Oncology (AUA/SUO) released in 2023. Our objective is to contrast the different guidelines and examine the evidence on which their recommendations are based. Results: By thoroughly reviewing the guidelines from both organizations, we observed substantial agreement on the management of UTUC. However, we also identified noticeable differences among these guidelines, leading to a wide range of recommendations. These disparities might stem from variations in clinical practices, regional preferences, and the availability of resources. It is crucial to acknowledge that both the EAU and AUA/SUO base their guidelines on the latest scientific evidence and expert consensus within their respective regions. Conclusions: These findings underscore the importance of ongoing collaboration, knowledge exchange, and harmonization of guidelines to improve the standard of care for UTUC globally. Future research should focus on identifying areas of consensus and bridging the gaps between different international guidelines to enhance the management outcomes for this challenging disease.

How much energy do we need to ablate 1 cubic millimeter of stone during Thulium Fiber Laser lithotripsy? An in vitro study.

INTRODUCTION: Both Holmium:yttrium-aluminium-garnet (Ho:YAG) laser and Thulium Fiber Laser (TFL) can effectively treat all urinary stone types. This in vitro study evaluated the ablation volume per pulse (AVP) and required energy needed to ablate 1mm3 (RE, J/mm3) of various stone types at different laser settings with TFL. METHODS: 272-µm core-diameter laser fibers (Boston Scientific©) were connected to a 50 Watts TFL generator (IPG®). An experimental setup immerged human stones of calcium oxalate monohydrate (COM), uric acid (UA), and cystine (CYS) with a single pulse lasing emission (0.5/0.8/1 J), in contact mode. Stones were dried out before three-dimensional scanning to measure AVP and deduce from the pulse energy (PE) and AVP the RE. A direct comparison with known Ho:YAG's AVP and RE was then carried out. RESULTS: AVP for COM stones was significantly greater than those for CYS stones and similar to UA stones (p = 0.02 and p = 0.06, respectively). If AVP increased with PE against COM and UA stones, AVP decreased against CYS stones. 1 J PE resulted in a threefold lower RE compared with other PE for COM stones. On the contrary, RE for CYS increased with PE, whereas PE did not had influence on RE for UA. TFL was associated with greater AVP for COM, but lower for UA and CYS stones compared to Ho:YAG laser. CONCLUSION: This in vitro study firstly describes the ablation volume per pulse and required energy to treat a cubic millimeter of three frequent human stone types, and suggest TFL could not be suited for cystine. Therefore, stone composition could be considered when choosing the laser source for lithotripsy.