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.

Outcomes of Minimally Invasive Inguinal Hernia Repair at the Time of Robotic Radical Prostatectomy.

Abdominal straining associated with voiding dysfunction or constipation has traditionally been associated with the development of abdominal wall hernias. Thus, classic general surgery dictum recommends that any coexistent bladder outlet obstruction should be addressed by the urologist before patients undergo surgical repair of a hernia. While organ-confined prostate cancer is usually not associated with the development of lower urinary tract symptoms, a modest proportion of patients treated with radical prostatectomy may have coexisting benign prostatic hyperplasia with elevated symptom scores and hernias may be incidentally detected at the time of surgery. Furthermore, dissection of the space of Retzius during retropubic or minimally invasive prostatectomy may result exposure of abdominal wall defects which may have been present, but asymptomatic if plugged with preperitoneal fat. Herein we examine the literature regarding the incidence of postoperative inguinal hernias after prostatectomy, review potential risk factors which could aid in preoperative patient identification, and discuss the published experience regarding concurrent hernia repair at the time of open or minimally invasive radical prostatectomy.

The Impact of Single-Use Cystoscopes on Clinical Time Workflow in an Outpatient Setting.

OBJECTIVE: To evaluate the change in overall clinical encounter time and clinical capacity after transitioning to single-use cystoscopes (Ambu A/S, Ballerup, Denmark) in an outpatient urology setting. METHODS: A single-institution prospective study in an outpatient urology procedure clinic was performed. Discrete categories for each portion of nursing care responsibilities were defined, and time spent during each category was recorded. Two separate clinic days were observed and analyzed: one where the clinic exclusively used reusable cystoscopes and the other after the transition to single-use cystoscopes occurred. Additionally, clinic schedules were reviewed from all procedure clinics in the 3-month periods before and after the transition to single-use cystoscopes. Outcomes included overall clinical encounter time and the number of procedures per clinic day. RESULTS: There were 12 flexible cystoscopies performed during each of the observed clinic days. Preliminary cystoscope cleaning and transportation tasks by nursing staff were eliminated when utilizing single-use cystoscopes. Average total encounter time decreased from 66 to 44 minutes, resulting in a 34% reduction in clinical encounter time. The median number of flexible cystoscopy procedures increased after the transition from 9 (IQR 7-12) to 16 (IQR 11-17), representing a 78% increase (P = .003). CONCLUSION: Transition to a completely single-use cystoscopy outpatient procedure clinic improved clinical efficiency and facilitated an increased number of procedures per clinic day.

In Pursuit of the Optimal Dusting Settings with the Thulium Fiber Laser: An In Vitro Assessment.

Objective: Low energy and high frequency settings are used in stone dusting for holmium lasers. Such settings may not be optimal for thulium fiber laser (TFL). With the seemingly endless combination of settings, we aim to provide guidance to the practicing urologists and assess the efficiency of the TFL platform in an automated in vitro "dusting model." Materials/Methods: Three experimental setups were designed to investigate stone dusting produced by an IPG Photonics TLR-50 W TFL system using 200 µm fiber and soft BegoStone phantoms. The most popular 10 and 20 W dusting settings among endourologist familiar with TFL were evaluated. We directly compared short pulse (SP) vs long pulse (LP) mode using various combinations of pulse energy (Ep) and pulse frequency (F). Thereafter, we tested the 10 and 20 W settings and compared them among each other to elucidate the most efficient settings at each power. Treatments were performed under the same total laser energy delivered to the stone at four different standoff distances (SDs) with a clinically relevant scanning speed of either 1 or 2 mm/sec. Ablation volumes were quantified by optical coherence tomography to assess stone dusting efficiency. Fragment size after ablation at different pulse energies was evaluated by sieving and evaluating under a microscope after treatment. Results: Overall, SP provided greater ablation volume when compared with LP. Our dusting efficiency model demonstrated that the maximum stone ablation was achieved at the combination of high energy/low frequency settings (p < 0.005) and at a SD of 0.2 mm. At all tested pulse energies, no stone phantoms were broken into fragments >1 mm. Conclusions: During stone dusting with TFL, SP offers superior ablation to LP settings. Optimal dusting at clinically relevant scanning speeds of 1 and 2 mm/sec occurs at high energy/low frequency settings. Thulium lithotripsy with high Ep does not result in increased fragment size.

Benchtop Evaluation of Miniature Percutaneous Nephrolithotomy Lithotrites.

Introduction: Percutaneous nephrolithotomy (PCNL) is the preferred treatment for kidney stones >2 cm. While PCNL has traditionally been performed using 24F to 30F access sheaths, there is a trend toward smaller sheaths and scopes to perform mini-PCNL (mPCNL). We performed benchtop assessment of multiple mPCNL lithotrites. Methods: One 1 cm3, hard Begostone phantom was placed in a cylinder with four 5.5 mm cylindrical openings to simulate the size of a 16.5F mPCNL sheath. Lithotripsy was performed with the 1.5 and 1.9 mm Trilogy, 1.83 mm ShockPulse, or a 200 µm Holmium:YAG (Ho:YAG) laser. Suction was used for the mechanical lithotrites. The Trilogy probes were set at 50% impact, 6 Hz, 80% ultrasound and 10% suction. The ShockPulse was used at high-power setting with low suction. The 1.9 mm Trilogy probe was used with a 15F mini-nephroscope. The 1.83 mm ShockPulse, 1.5 mm Trilogy and laser fiber were used with a 12F mini-nephroscope. The 120 W holmium laser was set at 0.5 J/70 Hz Moses-Distance. Ten independent runs were performed with modality. Time to complete stone clearance was recorded and mass stone clearance rates were calculated. Results: The Trilogy 1.9 mm showed superior stone clearance rate (11.69 ± 3.68 mg/s) vs the ShockPulse (SP) 1.83 mm (6.29 ± 1.37 mg/s, p = 0.003), the laser fiber (4.73 ± 0.61 mg/s, p < 0.0005), and the Trilogy 1.5 mm (6.84 ± 1.21 mg/s). The 200 µm laser fiber was inferior to all mechanical lithotrites. There was no difference between the 1.5 mm Trilogy and the 1.83 mm ShockPulse (p = 0.772). This translates to 3.9, 4.8, and 8.1 minutes less treatment time vs the 1.5 mm Trilogy, SP, and laser, respectively, for a spherical 1.5 cm diameter calcium oxalate monohydrate stone. Conclusion: Among these four commonly used mPCNL lithotripters, the Trilogy 1.9 mm demonstrated superior stone clearance rates in this benchtop model vs the Ho:YAG laser, 1.83 mm SP, and Trilogy 1.5 mm. Future clinical testing is warranted to evaluate the optimal lithotrite for mPCNL.

Evaluation and Management of the Undescended Testis in Puerto Rico: A Single Surgeon's 10 Years of Experience.

OBJECTIVE: Cryptorchidism is an abnormality of the male genitourinary tract in which one or both testes fail to descend into the scrotum. The American Urological Association (AUA) clinical guidelines for the evaluation and treatment of cryptorchidism were recently published. We reviewed our experience with the evaluation and management of our patients and examined our findings with respect to the AUA and European Association of Urology (EAU) guidelines. METHODS: Data were obtained from pediatric patients who underwent a surgical intervention for an undescended testis from 2007 through 2017 at HIMA Hospital and the University Pediatric Hospital (both in Puerto Rico); all the surgeries were performed by the same surgeon. A total of 754 patients were identified; 142 patients were excluded due to lack of follow-up data (N = 612). The data obtained included age, testes locations, radiologic and surgical findings, and postoperative results. RESULTS: At their initial evaluations, a large proportion of the patients (46.4%) came accompanied with radiographic imaging. These findings were consistent with those of the physical examination in 58.5% of the patients and with the surgical findings in 63.1% (sensitivity 77.9%, specificity 45.8%). Our data showed that the median referral age was 24 months, which suggests that there was a significant delay in diagnosis. At the time of surgery, the average age of the patients who required an orchiectomy was 3.93 years, while those who underwent an orchiopexy had an average age of 3.28 years. CONCLUSION: Our data reveal that, despite its lack of usefulness, radiologic imaging continues to be included in the diagnostic workups of children newly identified with cryptorchidism in Puerto Rico. In addition, and contrary to the guidelines, there tends to be a significant delay in treatment with surgical intervention. It is important to continue to educate our referring physicians on the AUA and EUA guidelines in order to create awareness and encourage the proper diagnostic and treatment approach for cryptorchidism.