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.

A comparison between vapor tunnel and virtual basket for the treatment of proximal ureteral stones using holmium:YAG laser (Cyber Ho): which is the best tool to reduce retropulsion?

PURPOSE: To compare vapor tunnel (VT) and virtual basket (VB) tools to reduce retropulsion in the treatment of proximal ureteral stones. METHODS: Patients with a single proximal ureteral stone were randomly assigned to holmium laser lithotripsy with the use of VT (Group A) or VB (Group B) tool. The 150W holmium:YAG cyber Ho generator was used. We compared operative time, dusting time, need for flexible ureteroscopy due to stone push-up and occurrence of ureteral lesions. The stone-free rate (SFR) and the occurrence of postoperative ureteral strictures were assessed. RESULTS: 186 patients were treated, of which 92 with the VT (49.5%, Group A) and 94 with the VB (50.5%, Group B). Mean stone size was 0.92 vs. 0.91 cm in Groups A vs. B (p = 0.32). Mean total operative time and dusting time were comparable between groups. 7 (7.6%) vs. 6 (6.4%) patients in Groups A vs. B required a flexible ureteroscope because of stone push-up (p = 0.12). Ureteral mucosa lesions were observed in 15 (16.3%) vs. 18 (19.1%) cases in the VT vs. VB group (p = 0.09). 1-Month SFR was comparable (97.8% vs. 95.7%, p = 0.41). We observed one case (1.1%) of postoperative ureteral stricture in the VT group vs. two cases (2.1%) in the VB group (p = 0.19). CONCLUSIONS: VT and VB are equally safe and effective tools in reducing retropulsion of ureteral stones. Operative time, dusting time and SFR were comparable. They also equally avoided stone push-up and prevented ureteral lesions, which may later occur in ureteral strictures.

Efficacy of flexible ureterorenoscopy with holmium laser in the management of calyceal diverticular calculi.

The purpose of this study was to evaluate the efficacy and safety of flexible ureteroscopy with holmium laser lithotripsy in the management of calyceal diverticular calculi. In this study, we retrospectively analyzed the clinical data of 27 patients with calyceal diverticular calculi admitted to the Department of Urology of the Zigong First People's Hospital from May 2018 to May 2021. Intraoperatively, the diverticular neck was found in all 27 patients, but flexible ureterorenoscopy lithotripsy was not performed in 2 cases because of the slender diverticular neck, and the success rate of the operation was 92.6%. Of the 25 patients with successful lithotripsy, the mean operative time was 76.9 ± 35.5 (43-200) min. There were no serious intraoperative complications such as ureteral perforation, mucosal avulsion, or hemorrhage. Postoperative minor complications (Clavien classification I-II) occurred in 4 (16%) patients. The mean hospital stay was 4.4 ± 1.7 (3-12) days. The stone-free rate was 80% at the 1-month postoperative follow-up. After the second-stage treatment, the stone-free rate was 88%. In 22 cases with complete stone clearance, no stone recurrence was observed at 5.3 ± 2.6 (3-12) months follow-up. This retrospective study demonstrated that flexible ureterorenoscopy with holmium laser is a safe and effective choice for the treatment of calyceal diverticular calculi, because it utilizes the natural lumen of the human body and has the advantages of less trauma, fewer complications, and a higher stone-free rate.

Observation and comparison of gas formation during holmium:YAG laser lithotripsy of cystine, uric acid, and calcium oxalate stones: a chromatographic and electron microscopic analysis.

The primary aim of the present in vitro study is to analyze the chemical content of the bubbles occurring during the fragmentation of cystine stones with both the high-power and low-power holmium:YAG (Ho:YAG) lasers. The secondary aim is to discuss their clinical importance. Three types of human renal calculi calcium oxalate monohydrate (COM), cystine, and uric acid were fragmented with both low-power and high-power Ho:YAG lasers in separate experimental setups at room temperature, during which time it was observed whether gas was produced. After laser lithotripsy, a cloudy white gas was obtained, after the fragmentation of cystine stones only. A qualitative gas content analysis was performed with a gas chromatography-mass spectrometry (GC-MS) device. The fragments in the aqueous cystine calculi setup were dried and taken to the laboratory to be examined by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) and X-ray diffraction analysis. No gas production was observed after fragmentation in the COM and uric acid stones. Free cystine, sulfur, thiophene, and hydrogen sulfide gas were produced by both low-power and high-power Ho:YAG laser lithotripsy of the cystine stones. In the SEM-EDX mapping analysis, a free cystine molecule containing 42.8% sulfur (S), 21% oxygen (O), 14.9% carbon (C), and 21% nitrogen (N) atoms was detected in the cystine stone experimental setup. The evidence obtained, which shows that hydrogen sulfide emerges in the gaseous environment during Ho:YAG laser fragmentation of cystine stones, indicates that caution is required to prevent the risk of in vivo production and toxicity.

Exploring optimal settings for safe and effective thulium fibre laser lithotripsy in a kidney model.

OBJECTIVES: To explore the optimal laser settings and treatment strategies for thulium fibre laser (TFL) lithotripsy, namely, those with the highest treatment efficiency, lowest thermal injury risk, and shortest procedure time. MATERIALS AND METHODS: An in vitro kidney model was used to assess the efficacy of TFL lithotripsy in the upper calyx. Stone ablation experiments were performed on BegoStone phantoms at different combinations of pulse energy (EP ) and frequency (F) to determine the optimal settings. Temperature changes and thermal injury risks were monitored using embedded thermocouples. Experiments were also performed on calcium oxalate monohydrate (COM) stones to validate the optimal settings. RESULTS: High EP /low F settings demonstrated superior treatment efficiency compared to low EP /high F settings using the same power. Specifically, 0.8 J/12 Hz was the optimal setting, resulting in a twofold increase in treatment efficiency, a 39% reduction in energy expenditure per unit of ablated stone mass, a 35% reduction in residual fragments, and a 36% reduction in total procedure time compared to the 0.2 J/50 Hz setting for COM stones. Thermal injury risk assessment indicated that 10 W power settings with high EP /low F combinations remained below the threshold for tissue injury, while higher power settings (>10 W) consistently exceeded the safety threshold. CONCLUSIONS: Our findings suggest that high EP /low F settings, such as 0.8 J/12 Hz, are optimal for TFL lithotripsy in the treatment of COM stones. These settings demonstrated significantly improved treatment efficiency with reduced residual fragments compared to conventional settings while keeping the thermal dose below the injury threshold. This study highlights the importance of using the high EP /low F combination with low power settings, which maximizes treatment efficiency and minimizes potential thermal injury. Further studies are warranted to determine the optimal settings for TFL for treating kidney stones with different compositions.

Laser safety, warnings, and limits in retrograde intrarenal surgery.

OBJECTIVE: To analyze the current information about laser safety in retrograde intrarenal surgery (RIRS), focusing on the two main laser technologies that we use in urology, the holmium:yttrium-aluminum-garnet (Ho:YAG) laser, and the thulium fiber laser (TFL). METHODS: Narrative overview of the most relevant articles published in MEDLINE and Scopus databases about this subject. RESULTS: TFL and Ho:YAG laser at similar settings (0.2 J/40 Hz) have similar volume-averaged temperature increase and the average heating rate increase proportionally to laser power, especially when high frequencies are used. Recent preclinical data, comparing both laser technologies at different laser settings, agreed that when the delivered energy increases in expenses of higher frequencies, the thermal damage increases too. Higher frequencies, despite of the rise of temperature in the irrigation medium, can cause accidental thermal lasering lesions. CONCLUSION: The use of low frequency settings and a proper irrigation is critical to avoid thermal injury in endoscopic laser lithotripsy. In addition, the use of laser safety eyeglasses is recommended in Ho:YAG and TFL ELL.

Thulium fiber laser cystolithotripsy under local anesthesia: A day care procedure.

INTRODUCTION: Bladder stones account for 5% of all urolithiasis. Patients present with LUTS or acute urinary retention. Thus, warranting an early intervention. Minimally invasive approach with laser lithotripsy is the present gold standard to treat bladder stones. AIMS AND OBJECTIVES: To evaluate the outcomes of TFL (60 W) for bladder stones performed under local anesthesia as a day-care procedure. MATERIALS AND METHODS: This was a retrospective single-center study conducted after obtaining IRB approval. Study period was between June 2021 and June 2022 were included. All patients were operated under local anesthesia as a day care procedure. The procedure was carried out using an 18 Fr laser sheath and calculus dusted using TFL energy (15-30 W). Parameters including operative time in minutes, complications were recorded. Patients were encouraged oral and normal voiding in the immediate post-op period. RESULTS: A total of 47 patients with bladder stones presented during this period. Of these, 30 underwent laser lithotripsy (TFL) for bladder calculi. The clinical presentation of patients was LUTS in 28 (93%) and 5 (16%) patients had AUR. The average size of the stone in this series was 15 ± 2.8 mm. The mean duration of laser lithotripsy was 15 ± 5.4 min. Energy to dust the stone was variable with mean LASER energy of 18.23 ± 10 W. All patients tolerated the procedure well and none required conversion to conventional anesthesia. One patient failed to void in the post-op period. 100% clearance rate was documented in all patients. CONCLUSION: Thulium fiber laser for transurethral cystolithotripsy of bladder stones under local anesthesia is a feasible technique with minimal morbidity and good outcome.

Factors Affecting Holmium Laser Efficiency: Comparison of Laryngeal Mask Airway and Endotracheal Intubation During Ureteroscopy for Renal Stones.

Introduction: Holmium laser lithotripsy is a standard energy source used for treatment of kidney stones during flexible ureteroscopy. Efficiency of laser surgery may be affected by patient and operator characteristics or perioperative management. Here, we sought to examine intraoperative data from patients undergoing high frequency dusting with high-powered holmium laser lithotripsy to evaluate surgical and demographic factors associated with lasing efficiency (LE). Methods: A total of 82 intraoperative reports were analyzed from an ongoing laser lithotripsy clinical trial evaluating the Lumenis Pulse™ 120H holmium laser with renal stones up to 20 mm in diameter with and without Moses 2.0 technology. For each case, the total pause time between lasing activations was corrected to remove lengthy pauses and divided by the total lasing time to calculate an efficiency percentage. This was then compared with patient demographics, anesthesia administration, stone burden, postoperative complications, and stone-free rates using both univariate and multivariate analyses. Results: Of the 82 included patients, 36 received endotracheal tube (ETT) intubation and 46 had a laryngeal mask airway (LMA). Patients with ETT had significantly higher LE (78.7%) compared to those with an LMA (73.3%) in our univariate analysis (p < 0.01) as well as in the multivariate model that adjusted for maximum stone size, number of stones, stone density, and patient body mass index (p < 0.05). There was also significantly higher mean LE in patients with no postoperative complications (76.3%) compared to those with any grade (I-V) Clavien-Dindo complication within 30 days after surgery (70.0%) (p < 0.05). Conclusions: Flexible ureteroscopy and laser lithotripsy cases with higher LE are associated with lower rates of postoperative complications. The data also support the use of ETT over LMA to improve overall LE; however, this remains one consideration among many for choosing anesthesia administration. Clinical Trial Registration number: NCT04505956.

The heat is on: the impact of excessive temperature increments on complications of laser treatment for ureteral and renal stones.

OBJECTIVE: Technological advancements in the field of urology have led to a paradigm shift in the management of urolithiasis towards minimally invasive endourological interventions, namely ureteroscopy and percutaneous nephrolithotomy. However, concerns regarding the potential for thermal injury during laser lithotripsy have arisen, as studies have indicated that the threshold for cellular thermal injury (43 °C) can be exceeded, even with conventional low-power laser settings. This review aims to identify the factors that contribute to temperature increments during laser treatment using current laser systems and evaluate their impact on patient outcomes. MATERIALS AND METHODS: To select studies for inclusion, a search was performed on online databases including PubMed and Google Scholar. Keywords such as 'temperature' or 'heat' were combined with 'lithotripsy', 'nephrolithotomy', 'ureteroscopy', or 'retrograde intrarenal surgery', both individually and in various combinations. RESULTS: Various strategies have been proposed to mitigate temperature rise, such as reducing laser energy or frequency, shortening the duration of laser activation, increasing the irrigation fluid flow rate, and using room temperature or chilled water for irrigation. It is important to note that higher irrigation fluid flow rates should be approached cautiously due to potential increases in intrarenal pressure and associated infectious complications. The utilization of a ureteral access sheath (UAS) may offer benefits by facilitating irrigation fluid outflow, thereby reducing intrapelvic pressure and intrarenal fluid temperature. CONCLUSION: Achieving a balance between laser power, duration of laser activation, and irrigation fluid rate and temperature appears to be crucial for urologists to minimize excessive temperature rise.

In vitro investigation of stone ablation efficiency, char formation, spark generation, and damage mechanism produced by thulium fiber laser.

To investigate stone ablation characteristics of thulium fiber laser (TFL), BegoStone phantoms were spot-treated in water at various fiber tip-to-stone standoff distances (SDs, 0.5 ~ 2 mm) over a broad range of pulse energy (Ep, 0.2 ~ 2 J), frequency (F, 5 ~ 150 Hz), and power (P, 10 ~ 30 W) settings. In general, the ablation speed (mm3/s) in BegoStone decreased with SD and increased with Ep, reaching a peak around 0.8 ~ 1.0 J. Additional experiments with calcium phosphate (CaP), uric acid (UA), and calcium oxalate monohydrate (COM) stones were conducted under two distinctly different settings: 0.2 J/100 Hz and 0.8 J/12 Hz. The concomitant bubble dynamics, spark generation and pressure transients were analyzed. Higher ablation speeds were consistently produced at 0.8 J/12 Hz than at 0.2 J/100 Hz, with CaP stones most difficult yet COM and UA stones easier to ablate. Charring was mostly observed in CaP stones at 0.2 J/100 Hz, accompanied by strong spark-generation, explosive combustion, and diminished pressure transients, but not at 0.8 J/12 Hz. By treating stones in parallel fiber orientation and leveraging the proximity effect of a ureteroscope, the contribution of bubble collapse to stone ablation was found to be substantial (16% ~ 59%) at 0.8 J/12 Hz, but not at 0.2 J/100 Hz. Overall, TFL ablation efficiency is significantly better at high Ep/low F setting, attributable to increased cavitation damage with less char formation.

Femtosecond laser lithotripsy: a novel alternative for kidney stone treatment? Evaluating the safety and effectiveness in an ex vivo study.

The Holmium (Ho:YAG) laser is presently the most extensively employed in laser lithotripsy for the management of kidney stones. Despite its adoption as the gold standard for laser lithotripsy, Ho:YAG laser lithotripsy poses three significant challenges, namely thermal effect, insufficient stone fragmentation, and stone displacement, which have garnered increased attention from urologic surgeons. Nowadays, the femtosecond laser is regarded as a potential alternative to the Ho:YAG laser due to its capacity to ablate diverse materials with minimal thermal effect. In our ex vivo investigation, we assessed the dimensions of ablation pits, the efficacy of ablation, the degree of stone fragmentation, the alterations in water temperature surrounding stones, and the degree of tissue damage associated with Femtosecond laser lithotripsy utilizing adjustable power settings (1-50 W). Our findings indicate that the ablation pits generated by the Femtosecond laser exhibited uniform geometries, and the effectiveness of ablation and fragmentation for Femtosecond laser lithotripsy were significantly and positively correlated with laser power. When the laser power remained constant, the Femtosecond laser with higher pulse energy demonstrated superior efficiency in stone ablation, but inferior performance in stone fragmentation. Conversely, the Femtosecond laser with higher pulse frequency exhibited the opposite behavior. Furthermore, the thermal effect increased proportionally with laser power, leading to a tentative recommendation of 10W laser power for future investigations. Our in vitro findings suggest that the Femtosecond laser holds promise as a safe and effective alternative to holmium lasers.

[Efficacy and safety of superpulse thulium laser lithotripsy in the intracavitary treatment of urinary calculi].

Objective: To evaluate the efficacy and safety of superpulse thulium laser lithotripsy in the intracavitary treatment of urinary calculi. Methods: From May 2021 to July 2022, patients diagnosed with urinary calculi were screened in four medical centers. Those who met the criteria were treated with superpulse thulium fiber laser under endoscope. The patients' perioperative conditions were recorded. The main effective index was stone-free rate (SFR) 4 weeks after operation, the main safety index was the failure rate of the experimental instruments during operation, and the secondary safety index was the incidence rate of perioperative complications. Results: A total of 76 eligible patients completed superpulse thulium fiber laser lithotripsy, with an average age of (52.0±11.1) years, 54 males and 22 females. There were 31 renal stones, 43 ureteral stones and 2 bladder stones. Percutaneous nephrolithotomy was performed in 17 patients. Ureteroscopy lithotripsy/flexible ureteroscopy lithotripsy was performed in 57 patients and transurethral bladder lithotripsy was in 2 patients. The lithotripsy time of all patients was (50.9±31.4) minutes. There was no failure of experimental instruments during the operation. Six patients refused follow-up examination after operation. The incidence of postoperative adverse events was 61.8% (47/76). One patient needed hospitalization due to inguinal hernia after operation, and the rest were classified as Clavien-dindo grade 1-2. The SFR was 94.3% (66/70) at 4 weeks after operation. Conclusion: It is effective and safe to use superpulse thulium fiber laser in the treatment of urinary calculi.

Comparison Between Holmium:YAG Laser with MOSES Technology vs Thulium Fiber Laser Lithotripsy in Retrograde Intrarenal Surgery for Kidney Stones in Adults: A Propensity Score-matched Analysis From the FLEXible Ureteroscopy Outcomes Registry.

PURPOSE: We evaluated stone-free rate and complications after flexible ureteroscopy for renal stones, comparing thulium fiber laser and holmium:YAG laser with MOSES technology. MATERIALS AND METHODS: Data from adults who underwent flexible ureteroscopy in 20 centers worldwide were retrospectively reviewed (January 2018-August 2021). Patients with ureteral stones, concomitant bilateral procedures, and combined procedures were excluded. One-to-one propensity score matching for age, gender, and stone characteristics was performed. Stone-free rate was defined as absence of fragments >2 mm on imaging within 3 months after surgery. Multivariable logistic regression analysis was performed to evaluate independent predictors of being stone-free. RESULTS: Of 2,075 included patients, holmium:YAG laser with MOSES technology was used in 508 patients and thulium fiber laser in 1,567 patients. After matching, 284 patients from each group with comparable baseline characteristics were included. Pure dusting was applied in 6.0% of cases in holmium:YAG laser with MOSES technology compared with 26% in thulium fiber laser. There was a higher rate of basket extraction in holmium:YAG laser with MOSES technology (89% vs 43%, P < .001). Total operation time and lasing time were similar. Nine patients had sepsis in thulium fiber laser vs none in holmium:YAG laser with MOSES technology (P = .007). Higher stone-free rate was achieved in thulium fiber laser (85% vs 56%, P < .001). At multivariable analysis, the use of thulium fiber laser and ureteral access sheath ≥8F had significantly higher odds of being stone-free. Lasing time, multiple stones, stone diameter, and use of disposable scopes showed significantly lower odds of being stone-free. CONCLUSIONS: This real-world study favors the use of thulium fiber laser over holmium:YAG laser with MOSES technology in flexible ureteroscopy for renal stones by way of its higher single-stage stone-free rate.

The initial experience of 4.5/6.5 Fr ureteroscopic laser lithotripsy under topical intraurethral anesthesia supplemented by preoperative and intraoperative medications.

PURPOSE: To assess the safety and effectiveness of the 4.5/6.5 Fr ureteroscopic laser lithotripsy (URSL) under topical intraurethral anesthesia (TIUA) compared to spinal anesthesia (SA). METHODS: A retrospective study was conducted on 47 (TIUA: SA = 23:24) patients receiving 4.5/6.5 Fr URSL from July 2022 to September 2022. For the TIUA group, atropine, pethidine, and phloroglucinol were used apart from lidocaine. In the SA group, patients received lidocaine and bupivacaine. We compare the two groups including stone-free rate (SFR), procedure time, anesthesia time, overall operative time, hospital stay, anesthesia failure, intraoperative pain, need for additional analgesia, cost, and complications. RESULTS: The conversion rate in the TIUA group was 4.35% (1/23). SFR was 100% in both groups. Surgical waiting time and anesthesia time were longer in the SA group (P < 0.001). There were no statistical differences in operational time and intraoperative pain. Patients developed grade 0-1 ureteral injuries. Post-surgical time out of bed was noticeably faster in the TIUA group (P < 0.001). The post-operative complication rate including vomiting and back pain was lower in the TIUA group (P = 0.005). CONCLUSION: TIUA had an equal surgical success rate and controlled patients' intraoperative pain as SA. It was superior in terms of TIUA's patient admission, waiting time for surgery, anesthesia time, post-operative time out of bed, low complications, and costs, especially for females.

Use of Moses 2.0 with extended frequency and optimized Moses vs. high-power laser in MiniPCNL: a randomized controlled trial.

The aim of the study was to compare standard high-power laser (with < 80 Hz) to extended frequency (> 100 Hz) lithotripsy during miniPCNL. 40 patients were randomized in to two groups undergoing MiniPCNL. For both groups, the Holmium Pulse laser Moses 2.0 (Lumenis) was used. For group A, standard high-power laser with < 80 Hz, with Moses distance was set using up to 3 J. For Group B, extended frequency (100-120 Hz) was used allowing up to 0.6 J. All patients underwent MiniPCNL using an 18 Fr balloon access. Demographics were comparable between groups. Mean stone diameter was 19 mm (14-23) with no differences between groups (p = 0.14). Mean operative time was 91 and 87 min for group A and B (p = 0.71), mean laser time was similar in both groups, 6.5 min and 7.5 min, respectively (p = 0.52) as well as the number of laser activations during the surgery (p = 0.43). Mean Watts used was 18 and 16 respectively being similar in both groups (p = 0.54) as well as the total KJoules (p = 0.29). Endoscopic vision was good in all surgeries. The endoscopic and radiologic stone free rate was achieved in all patients expect for two in both groups (p = 0.72). Two Clavien I complications were seen, a small bleeding for group A and a small pelvic perforation in group B. The use of high-power holmium laser with extended frequency and optimized Moses was effective and safe being comparable to standard high-power laser for MiniPCNL allowing more versatility with the setting range.

Application of Flexible Holmium Laser Sheath in Rigid Ureteroscopy for the Treatment of Impacted Upper Ureteral Stones.

OBJECTIVE: By comparing with rigid ureteroscopy (r-URS), we explored the application value of flexible holmium laser sheath combined with r-URS in treating impacted upper ureteral stones. We also verified its effectiveness, safety and economy and investigated its application prospects at community or primary hospitals. METHODS: From December 2018 to November 2021, 158 patients with impacted upper ureteral stones were selected from Yongchuan Hospital of Chongqing Medical University. Seventy-five patients in the control group were treated with r-URS, and 83 patients in the experimental group were treated with r-URS combined with a flexible holmium laser sheath if necessary. The operation time, postoperative hospital stay, hospitalization expenses, stone clearance rate after r-URS, auxiliary extracorporeal shock wave lithotripsy (ESWL) ratio, auxiliary flexible ureteroscope, the incidence of postoperative complications and the stone clearance rate after one month were observed. RESULTS: The postoperative hospital stay, stone clearance rate after r-URS, the ratio of auxiliary ESWL, the ratio of the auxiliary flexible ureteroscope, and total hospitalization expenses in the experimental group were significantly less than those in the control group (p < 0.05). There was no significant difference in operation time, postoperative complications, and stone clearance rate after one month between the two groups (p > 0.05). CONCLUSIONS: r-URS combined with flexible holmium laser sheath in treating impacted upper ureteral stones can improve the stone clearance rate and reduce hospitalization expenses. Therefore, it has a certain application value in community or primary hospitals.

The study of double-J stent free mode of flexible ureteroscopy and laser lithotripsy: a single centre experience.

OBJECTIVE: To evaluate the effectiveness and safety of flexible ureteroscopy in the treatment of kidney and upper ureteral calculi under double-J stent free mode. METHODS: Data from patients who underwent flexible ureteroscopy and laser lithotripsy between February 2018 and September 2021 were retrospectively and analysed. Cases were grouped according to pre- or postoperative use of the double-J stent (6 Fr): Post-F group (preoperative double-J stent but no postoperative double-J stent); Pre-F group (no preoperative stenting but with postoperative double-J stent); and Routine group (preoperative and postoperative double-J stenting). RESULTS: A total of 554 patients (390 male and 164 female) were included. The mean operation time was similar between the three groups, with no statistically significant difference. Incidence of grade 0-1 ureteral injury was significantly higher in the Pre-F group versus other groups, but there were no significant between-group differences in other operation-related complications. During follow-up, stent-associated complications were observed in the Pre-F and Routine groups, but not in the Post-F group. Stone clearance rates were similar between all groups at 1, 3 and 6 months following surgery. CONCLUSIONS: Flexible ureteroscopy using double-J stent free mode was found to be safe, feasible and effective in treating renal and upper ureteral calculi.

Renal pseudoaneurysm after holmium laser lithotripsy with flexible ureteroscopy: an unusual case report and literature review.

Pseudoaneurysms of the renal arteries are caused by focal rupture or perforation of the arterial wall, resulting in local bleeding. Such pseudoaneurysms can be observed in conditions such as nodular polyarteritis, penetrating or closed renal injury, and medically induced injuries (such as renal puncture biopsy, percutaneous nephrostomy, or partial nephrectomy). Flexible ureteroscopy (FURS) is performed entirely through the urethra to prevent potentially severe kidney damage. Because of this, almost no renal parenchymal hemorrhage occurs after FURS laser lithotripsy. Only four cases had been documented in the literature as of December 2022. In this report, we describe a 53-year-old man with a history of recurrent kidney stones who underwent FURS laser lithotripsy for bilateral kidney stones. The procedure was smoothly performed, and no active bleeding occurred. However, the patient developed recurrent macroscopic hematuria after discharge from the hospital, and renal angiography revealed a pseudoaneurysm in the distal right kidney. The pseudoaneurysm was treated with selective arterial embolization. Serious complications of FURS surgery are rare, particularly the formation of pseudoaneurysms. We report the present case to bring this potential complication to the attention of urologists.

Lasers for stone lithotripsy: advantages/disadvantages of each laser source.

PURPOSE: The purpose of this article was to make a narrative review of the literature in search of all articles regarding thulium:yttrium-aluminium-garnet (YAG), thulium laser fiber (TFL) and holmium:YAG (Ho:YAG) for lithotripsy from 2020 to 2023. A selection of articles of special interest and best evidence was made in order to give a better perspective on their advantages and disadvantages. RECENT FINDINGS: New Ho:YAG technologies of as high power, high frequency and pulsed modulations have shown promising results for lithotripsy by reducing retropulsion with good ablation efficiency. High peak power makes it particularly good for percutaneous nephrolithotomy. High intrarenal temperatures and correct setting are still concerning points.TFL has arrived to be one of the main players in flexible ureteroscopy. Being highly efficient and quick, and by producing micro-dusting the laser is quickly heading to become a gold standard. The new pulsed Thulium YAG is the newest laser. For now, only in-vitro studies show promising results with efficient lithotripsy. As the peak power lies between Ho:YAG and TFL it may be able to adequately perform when needing and low power lithotripsy. SUMMARY: Several new technologies have been developed in the last years for stone lithotripsy. All being efficient and safe if well used. Different advantages and disadvantages of each laser must be taken into consideration to give each laser the proper indication.