Totally tubeless, tubeless, and tubed percutaneous nephrolithotomy for treating kidney stones.

BACKGROUND: Percutaneous nephrolithotomy (PNL) is the standard of care for removing large kidney stones (> 2 cm). Once the procedure is complete, different exiting strategies exist to manage the percutaneous tract opening, including placement of an external nephrostomy tube, placement of an internal ureteral stent, or no external or internal tube. The decision to place or not place a tube is handled differently among clinicians and may affect patient outcomes. OBJECTIVES: To assess the effects of tubeless PNL (with ureteral stenting), totally tubeless PNL (without ureteral stenting or nephrostomy), and standard PNL (nephrostomy only) for the treatment of kidney stones in adults. SEARCH METHODS: We performed a systematic literature search in multiple biomedical databases (CENTRAL, MEDLINE, Embase, Web of Science), as well as in two clinical trial registries. We also handsearched reference lists of relevant publications and conference proceedings. We applied no language restrictions. The latest search update was conducted in September 2022. SELECTION CRITERIA: We included randomized controlled and quasi-randomized controlled trials of adult patients who received tubeless, totally tubeless, or standard PNL for treating kidney stones. We defined tubeless PNL as no nephrostomy tube, but ureteral stenting, while totally tubeless PNL meant no nephrostomy tube or ureteral stenting. Both interventions were compared to standard PNL with placement of a nephrostomy tube (only). We considered access tubes of any sizes. We only considered unilateral PNL with single-tract access. There were no exclusions on stone composition, size, or location. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the literature, extracted data, assessed risk of bias, and rated the certainty of evidence using GRADE. Primary outcomes were severe adverse events and postoperative pain, and secondary outcomes were operating time, length of hospital stay, and stone-free rate. We used the random-effects model for meta-analysis. MAIN RESULTS: We included 10 studies in the review. Participant age varied among studies, ranging from 20 to 60 years. Detailed information on stone characteristics was rarely presented. Tubeless PNL versus standard PNL We are very uncertain whether there is a difference in severe adverse events (SAEs) between tubeless PNL and standard PNL (risk ratio (RR) 1.53, 95% confidence interval (CI) 0.14 to 16.46; I2 = 42%; 2 studies, 46 participants; very low-certainty evidence). Tubeless PNL may have little to no effect on pain on postoperative day one (mean difference (MD) 0.56 lower, 95% CI 1.34 lower to 0.21 higher; I2 = 84%; 4 studies, 186 participants; low-certainty evidence), and probably results in little to no difference in operating room time (MD 0.40 longer (in minutes), 95% CI 4.82 shorter to 5.62 longer; I2 = 0%; 3 studies, 81 participants; moderate-certainty evidence). Tubeless PNL may reduce length of hospital stay (MD 0.90 shorter, 95% CI 1.45 shorter to 0.35 shorter; I2 = 84%; 6 studies, 238 participants; low-certainty evidence). We are very uncertain of the effect of tubeless PNL on blood transfusions (RR 0.64, 95% CI 0.16 to 2.52; I2 = 0%; 4 studies, 161 participants; very low-certainty evidence), sepsis or fever (RR 0.50, 95% CI 0.05 to 4.75; I2 = not applicable; 2 studies, 82 participants; very low-certainty evidence), or readmissions (RR 1.00, 95% CI 0.07 to 14.21; I2 = not applicable, 1 study, 24 participants; very low-certainty evidence). Totally tubeless versus standard PNL Totally tubeless PNL may result in lower SAE rates (RR 0.49, 95% CI 0.19 to 1.25; I2 = 0%; 2 studies, 174 participants; low-certainty evidence) and pain on postoperative day one (MD 3.60 lower, 95% CI 4.24 lower to 2.96 lower; I2 = Not applicable; 1 study, 50 participants; low-certainty evidence). Totally tubeless PNL may result in little to no difference in operating room time (MD 6.23 shorter (in minutes), 95% CI 14.29 shorter to 1.84 longer; I2 = 72%; 2 studies, 174 participants; moderate-certainty evidence) and sepsis or fever (RR 0.33, 95% CI 0.01 to 7.97; I2 = not applicable; 1 study, 90 participants; low-certainty evidence). Totally tubeless PNL likely shortens the length of hospital stay (MD 1.55 shorter, 95% CI 1.82 shorter to 1.29 shorter; I2 = 0%; 4 studies, 274 participants; moderate-certainty evidence). We are very uncertain of the effect of totally tubeless PNL on blood transfusions (RR 0.62, 95% CI 0.26 to 1.48; I2 = 0%; 4 studies, 274 participants; very low-certainty evidence) or readmissions (RR not estimable, 95% CI not estimable; I2 = not applicable; 1 study, 50 participants; very low-certainty evidence). We found no studies comparing tubeless mini versus standard mini-PNL or totally tubeless mini versus standard mini-PNL. AUTHORS' CONCLUSIONS: When comparing tubeless to standard PNL with regard to the predefined primary outcomes of this review, there may be little difference in early postoperative pain, while we are very uncertain of the effect on SAEs. People treated with tubeless PNL may benefit from a reduced length of stay compared to standard PNL. When comparing totally tubeless to standard PNL, early postoperative pain and severe adverse events may be reduced with totally tubeless PNL. The certainty of evidence by outcome was mostly very low (range: moderate to very low) for the comparison of tubeless to standard PNL and low (range: moderate to very low) for the comparison of totally tubeless to standard PNL. The most common reasons for downgrading the certainty of the evidence were study limitations, inconsistency, and imprecision. We did not find randomized trial evidence for other comparisons. Overall, further and higher-quality studies are needed to inform clinical practice.

In vivo Temperature Assessment during Holmium Laser Enucleation of the Prostate.

INTRODUCTION: Holmium laser enucleation of the prostate (HoLEP) has become popular worldwide for the surgical treatment of benign prostate hyperplasia. Holmium laser is considered an ideal transurethral thermomechanical device for enucleating the prostate. Although there is evidence on Ho:YAG laser-related heat generation, the studies mainly investigated ex vivo temperature generation during holmium laser lithotripsy. In this in vivo study, we aimed to assess for the first time the real-time heat generated during HoLEP. METHODS: Fifteen HoLEP procedures were included. The study was conducted over a time period of 16 months. To investigate the temperature generation, a preoperatively inserted rectal temperature probe and a temperature sensor within a suprapubic bladder catheter were used to record the temperature change during enucleation and coagulation. RESULTS: The mean values of the temperature change during the laser enucleation and coagulation were -0.35 ± 0.203 K (IQR: 0.23) and +0.14 ± 0.259 K (IQR: 0.3), respectively, in rectal measurements. Temperature differences during laser use and coagulation were <+1 K and <+5 K, respectively, in bladder measurements. We measured no temperature >37.1°C during the procedures and no temperature values considered harmful to the human body. CONCLUSION: Sufficient irrigation flow rates and irrigation monitoring during HoLEP are obligatory. To prevent a high and uncontrolled temperature rise, the surgeon or operating room staff should pay attention to the irrigation's continuity.

Temperature assessment study of ex vivo holmium laser enucleation of the prostate model.

PURPOSE: There isscarce evidence to date on how temperature develops during holmium laser enucleation of the prostate (HoLEP). We aimed to determine the potential heat generation during HoLEP under ex vivo conditions. METHODS: We developed two experimental setups. Firstly, we simulated HoLEP ex vivo using narrow-neck laboratory bottles mimicking enucleation cavities and a prostate resection trainer. Seven temperature probes were placed at different locations in the experimental setup, and the heat generation was measured separately during laser application. Secondly, we simulated high-frequency current-based coagulation of the vessels using a roller probe. RESULTS: We observed that the larger the enucleated cavity, the higher the temperature rises, regardless of the irrigation flow rate. The highest temperature difference with an irrigation flow was approximately + 4.5 K for a cavity measuring 100ccm and a 300 ml/min irrigation flow rate. The higher flow rate generates faster removal of the generated heat, thus cooling down the artificial cavity. Furthermore, the temperature differences at different irrigation flow rates (except at 0 ml/min) were consistently below 5 K. Within the resection trainer, the temperature increase with and without irrigation flow was approximately 0.5 K and 3.0 K, respectively. The mean depth of necrosis (1084 ± 176 µm) achieved by the roller probe was significantly greater when using 144 W energy. CONCLUSION: Carefully adjusted irrigation and monitoring during HoLEP are crucial when evacuating the thermal energy generated during the procedure. We believe this study of ours provides evidence with the potential to facilitate clinical studies on patient safety.

A novel endoimaging system for endoscopic 3D reconstruction in bladder cancer patients.

INTRODUCTION: The methods employed to document cystoscopic findings in bladder cancer patients lack accuracy and are subject to observer variability. We propose a novel endoimaging system and an online documentation platform to provide post-procedural 3D bladder reconstructions for improved diagnosis, management and follow-up. MATERIAL AND METHODS: The RaVeNNA4pi consortium is comprised of five industrial partners, two university hospitals and two technical institutes. These are grouped into hardware, software and clinical partners according to their professional expertise. The envisaged endoimaging system consists of an innovative cystoscope that generates 3D bladder reconstructions allowing users to remotely access a cloud-based centralized database to visualize individualized 3D bladder models from previous cystoscopies archived in DICOM format. RESULTS: Preliminary investigations successfully tracked the endoscope's rotational and translational movements. The structure-from-motion pipeline was tested in a bladder phantom and satisfactorily demonstrated 3D reconstructions of the processing sequence. AI-based semantic image segmentation achieved a 0.67 dice-score-coefficient over all classes. An online-platform allows physicians and patients to digitally visualize endoscopic findings by navigating a 3D bladder model. CONCLUSIONS: Our work demonstrates the current developments of a novel endoimaging system equipped with the potential to generate 3D bladder reconstructions from cystoscopy videos and AI-assisted automated detection of bladder tumors.

Feasibility of an Updated Randomised Controlled Trial on Surgical Urolithiasis Treatments: The Pilot Trial for the German Endoscopic versus Shock Wave Therapy Study (GESS).

Data comparing treatments for urolithiasis are often outdated, with inconsistent results or poor methodological and reporting quality. We report a pilot study in preparation for a larger multicentre randomised controlled trial (RCT) comparing shockwave therapy and ureteroscopy in patients with a single urinary stone of ≤20 mm in the upper urinary tract. Primary objectives included screening completeness, patients' willingness to participate, their remaining in the study, the suitability of the eligibility criteria, and the acceptability of the outcome measures. Screened individuals not invited to participate were those with no indication for active treatment among referred patients (n = 166), those who staff failed to screen (n = 99), and patients not meeting the inclusion criterion of a single stone (n = 422). Of the 176 patients invited, 116 refused to participate. Ultimately, we were able to recruit 60 patients within 34 mo. All patients underwent their allocated treatments. This pilot trial provides an in-depth analysis of the feasibility of an RCT on surgical treatments for upper urinary tract urolithiasis in a highly regulated health care system. The study procedures and outcome measures proved acceptable and feasible. On the basis of these data, we propose a pragmatic, multicentre RCT to deliver updated, high-level evidence on the efficacy of currently available treatments for urolithiasis. PATIENT SUMMARY: We performed a small pilot trial comparing current treatments in urolithiasis. We were able to prove the feasibility of a larger multi-institutional trial with regard to the time needed to recruit an adequate number of patients and the acceptability of the treatments and outcome measures.

Thermal effects of thulium: YAG laser treatment of the prostate-an in vitro study.

PURPOSE: To objectively determine whether there is potential thermal tissue damage during Tm:YAG laser-based LUTS treatment. METHODS: Our experimental model was comprised of a prostatic resection trainer placed in a 37 °C water bath. In a hollowed-out central area simulating the urethral lumen, we placed a RigiFib 800 fibre, irrigation inflow regulated with a digital pump, and a type K thermocouple. A second thermocouple was inserted 0.5/1 cm adjacently and protected with an aluminum barrier to prevent it from urethral fluid. We investigated continuous and intermittent 120 W and 80 W laser application with various irrigation rates in eight measurement sessions lasting up to 14 min. Thermal measurements were recorded continuously and in real-time using MatLab. All experiments were repeated five times to balance out variations. RESULTS: Continuous laser application at 120 W and 125 ml/min caused a urethral ∆T of ~ 15 K and a parenchymal temperature increase of up to 7 K. With 50 ml/min irrigation, a urethral and parenchymal ∆T of 30 K and 15 K were reached, respectively. Subsequently and in absence of laser application, prostatic parenchyma needed over 16 min to reach baseline body temperature. At 80 W lower temperature increases were reached compared to similar irrigation but higher power. CONCLUSIONS: We showed that potentially harming temperatures can be reached, especially during high laser power and low irrigation. The heat generation can also be conveyed to the prostate parenchyma and deeper structures, potentially affecting the neurovascular bundles. Further clinical studies with intracorporal temperature measurement are necessary to further investigate this potentially harming surgical adverse effect.

Soft Urinary Bladder Phantom for Endoscopic Training.

Bladder cancer (BC) is the main disease in the urinary tract with a high recurrence rate and it is diagnosed by cystoscopy (CY). To train the CY procedures, a realistic bladder phantom with correct anatomy and physiological properties is highly required. Here, we report a soft bladder phantom (FlexBlad) that mimics many important features of a human bladder. Under filling, it shows a large volume expansion of more than 300% with a tunable compliance in the range of 12.2 ± 2.8 - 32.7 ± 5.4 mL cmH2O-1 by engineering the thickness of the bladder wall. By 3D printing and multi-step molding, detailed anatomical structures are represented on the inner bladder wall, including sub-millimeter blood vessels and reconfigurable bladder tumors. Endoscopic inspection and tumor biopsy were successfully performed. A multi-center study was carried out, where two groups of urologists with different experience levels executed consecutive CYs in the phantom and filled in questionnaires. The learning curves reveal that the FlexBlad has a positive effect in the endourological training across different skill levels. The statistical results validate the usability of the phantom as a valuable educational tool, and the dynamic feature expands its use as a versatile endoscopic training platform.

Management and endovascular therapy of ureteroarterial fistulas: experience from a single center and review of the literature.

BACKGROUND: Ureteroarterial fistula (UAF) is a rare but potentially life threatening disease. The aim of this study was to evaluate the outcome of endovascular therapy for UAF treatment. METHODS: This retrospective case series evaluates a single center experience of percutaneous stent graft (SG) angioplasty and/or coil embolization for UAF. Patient follow-up included technical and early clinical success, complications and revisional procedures. We also conducted a systematic review of the literature reporting on endovascular UAF management. RESULTS: We identified 17 UAF in 16 patients (12 male, 4 female, mean age 69.8 ± 11.3 years) who underwent endovascular UAF therapy at our tertiary hospital. All patients presented with hematuria. 5/17 (29.4%) presented with flank pain, in 7 (41.2%) cases patients were in hypovolemic shock. Risk factors of UAF included chronic indwelling ureteral stents in all fistulas, major pelvic surgery in 13 cases (76.5%). In 6 cases (35.3%) SG were placed from the common iliac artery (CIA) to the external iliac artery (EIA) following coil embolization of the proximal internal iliac artery (IIA). SG placement without previous coil embolization was performed in 10 fistulas (58.8%). In one case only coil embolization of the IIA was performed. Mean follow-up was 654 (range: 1-3269) days. All procedures were technically successful and no procedure related deaths occurred during follow-up. During the initial hospital stay hematuria disappeared in 14/17 cases (82.4%). Overall, four patients suffered recurrent hematuria, which in three cases resolved after a secondary intervention. One recurrent UAF related death occurred during follow-up 229 days after initial treatment. A total of 152 UAF cases were additionally analyzed from our systematic literature review: SG placement with or without embolization was performed in 140 cases (92.1%) while embolization alone was done in 12 cases (7.9%). Complications included UAF recurrence (18/152, 11.8%), SG thrombosis (7/140, 5%), and SG infections (5/140, 3.6%) with an overall complications rate of 13.8%. Five patients died due to UAF (3.3%). CONCLUSION: Endovascular therapy offers high technical success rates and rapid bleeding control of UAF. Severe complications like SG occlusions or SG infections are rare but significant. Antibiotic treatment and single anti-platelet therapy improve SG durability as well as close and long follow-up to timely perform repeated endovascular or surgical treatment if necessary. EVIDENCE-BASED MEDICINE: Level 4, case series.

Endourological Training Using 3D-Printed Bladder Phantoms: Development and Prospective Evaluation.

Background: To create and evaluate a realistic, anatomically accurate, and user-friendly bladder phantom for reproducible endourological training purposes and endoscope mastery. Materials and Methods: The anatomy of full bladders was mapped from human computed tomography datasets. After a 3D model development process, content evidence and response process evidence (RPE) of the phantom were evaluated using the system usability scale (SUS), 5-point Likert scale questionnaires, and task execution of experienced urologists (U) and endoscopy-naive medical students (MS) in two training sessions (first vs second). Required validation cohort sizes (1:10) of the evaluating urologists (n = 12) and students (n = 115) were precalculated. Time measurements were recorded. Students were additionally evaluated by a validated global psychomotor assessment score (GPSS). Group comparisons were calculated by the Mann-Whitney U test. All tests were two sided with p < 0.05 considered statistically significant. Results: Content evidence was assessed by urologists with an "excellent" SUS score of 89.4 ± 5.9 and an average "agreement" of ≥4 pts in the Likert scale questionnaires. RPE was assessed by intra- and intergroup time comparison for the execution of endoscopic tasks (cystoscopy [CY], guidewire insertion, and tumor biopsy). For CY, U: first 17.6 ± 4.4 seconds vs second 12.4 ± 2.0 seconds, p = 0.002; MS: first 56.6 ± 28.2 seconds vs second 28.6 ± 14.7 seconds, p < 0.001; U vs MS: first U 17.6 ± 4.4 seconds vs first MS 56.6 ± 28.2 seconds, p < 0.001, second U 12.4 ± 2.0 seconds vs second MS 28.6 ± 14.7 seconds, p < 0.001. Significant time differences were documented for all tasks and sessions (p < 0.001). Additionally, significant GPSS differences were recorded between the sessions (GPSS: first 20.4 ± 5.1 pts vs second 24.7 ± 4.0 pts, p < 0.001). Conclusions: Our low-fidelity 3D-printed bladder, called BladCap, is an easy-to-assemble, inexpensive, and robust phantom. We present data, which establish construct validity to support use as a clinical training device.

Radiation exposure during retrograde intrarenal surgery (RIRS): a prospective multicenter evaluation.

PURPOSE: Retrograde intrarenal surgery (RIRS) may require extensive X-ray usage. We evaluated the impact of preoperative surgeon briefing regarding the inclusion and evaluation of fluoroscopy time (FT) and dose area product (DAP) in a multicenter study on the applied X-ray usage. METHODS: A prospective multicenter study of 6 tertiary centers was performed. Each center recruited up to 25 prospective patients with renal stones of any size for RIRS. Prior to study´s onset, all surgeons were briefed about hazards of radiation and on strategies to avoid high doses in RIRS. Prospective procedures were compared to past procedures, as baseline data. FT was defined as the primary outcome. Secondary parameters were stone-free rate (SFR), complications according to the Clavien, SATAVA and postureteroscopic lesion scale. Results were analyzed using T test, chi-squared test, univariate analysis and confirmed in a multivariate regression model. RESULTS: 303 patients were included (145 retro- and 158 prospective). Mean FT and DAP were reduced from 130.8 s/565.8 to 77.4 s/357.8 (p < 0.05). SFR was improved from 85.5% to 93% (p < 0.05). Complications did not vary significantly. Neither stone position (p = 0.569), prestenting (p = 0.419), nor surgeons' experience (> 100 RIRS) had a significant impact on FT. Significant univariate parameters were confirmed in a multivariate model, revealing X-ray training to be radiation protective (OR - 44, p = 0.001). CONCLUSIONS: Increased surgeon awareness of X-ray exposure risks has a significant impact on FT and DAP. This "awareness effect" is a simple method to reduce radiation exposure for the patient and OR staff without the procedures´ outcome and safety being affected.

Therapy-Refractory Matrix Staghorn in a Kidney Transplant Recipient: Endoscopic Percutaneous Morcellation as a Novel Treatment Option.

Background: Urolithiasis of transplant kidneys usually encompasses a challenging clinical situation due to specific anatomical conditions and the patients' immunological status. In this case report, we describe the treatment of a rare Proteus mirabilis matrix staghorn stone applying percutaneous nephrolithotomy in combination with matrix stone extraction by morcellation while utilizing endo-urological equipment designed for transurethral prostate surgery. Case Presentation: We present the case of a 44-year-old Caucasian woman who had undergone a post-mortal kidney transplant at age 37. After recurrent urinary tract infections, symptomatic obstructions of the transplant ureter, and multiple surgical interventions (73 Double-J stent and nephrostomy placements and three ureter re-implantations), permanent percutaneous nephrostomy drainage was established 6 years after her kidney transplantation. The patient was referred to our department due to recurrent dysfunction of the nephrostomy tube caused by blockage due to stone-matrix material and a staghorn calculus in the transplant kidney's collecting system. Microbiological examination of the stone material retrieved from the nephrostomy tube revealed massive P. mirabilis contamination. In this work, we present a novel percutaneous technique of matrix stone removal by relying on endoscopic equipment usually employed during prostate surgery by urologists. Conclusion: Percutaneous matrix stone morcellation is a technically challenging but feasible method that might be considered as a salvage treatment strategy in situations described earlier and in highly selective cases. However, for this extremely rare stone entity and individual clinical presentations, matrix stone morcellation seems to be a reasonable alternative before considering more radical interventions such as open nephrolithotomy. Selection criteria are a very soft stone, large-caliber percutaneous access to the collecting system, and enough space in the collecting system to execute morcellation.

Current Disposable Ureteroscopes: Performance and Limitations in a Standardized Kidney Model.

Objectives: Due to the increasing fragility of the instruments and rising concerns about the sterility of reprocessable scopes, several single-use devices for flexible ureteroscopy have been introduced. In this study, we compare currently available disposable digital and fiberoptic flexible ureteroscopes with a contemporary reusable fiberoptic device. Materials and Methods: LithoVue™, Pusen Uscope® (UE3011, UE3022), Flexor®Vue™, and a reusable fiber optic flexible ureteroscope (BOA vision®) were tested in kidney models. The setup included (1) visualization of all calices (correct assignment of colored pearls) and (2) the extraction of human calculi with a standard disposable extraction device (NGage®). We documented the effective visualization, stone extraction, and times to completion. In addition, the surgeons' workload and performance were determined using the National Aeronautics and Space Administration-Task Load Index. Results: In visualizing and identifying calices, the LithoVue and both generations of the Uscope performed similarly, but time to completion was significantly longer for all single-use devices in comparison with the Boa Vision. LithoVue retracted stones almost as well as the reusable scope (97% vs 95%/82%/96% stone clearance), while accessibility was impeded using Uscope UE3011, as reflected by the retrieval time per stone (73 vs 102 seconds/stone). This disadvantage has, however, been overcome with the new Uscope Generation UE3022, showing a retrieval time of only 65 seconds per stone, excelling over the reusable scope in this category. The Uscope UE3022 image quality was also rated best, but showed no significant difference. Conclusions: In comparison with disposable ureteroscopes available, LithoVue offers performance and characteristics similar to a reusable device, while the FlexorVu's performance does not yet yield satisfactory results for clinical use. The first generation of Uscope exhibits potential, but requires further technical improvements to match the performance of a reusable device. With the new-generation UE3022, Pusen has made significant improvement and offers a quality comparable with the LithoVue's.

Preclinical and Clinical Evaluation of a Novel, Variable-View, Rigid Endoscope for Female Cystoscopy.

OBJECTIVE: To evaluate the preclinical and clinical performance of the pivoting lens rigid Endocameleon (ECAM) endoscope in white light cystoscopy (WLC). MATERIALS AND METHODS: Preclinical evaluation was performed ex vivo in CT-based, anatomically accurate and validated bladder phantoms. Six defined tasks with objective endpoints were compared between ECAM-WLC and rigid WLC (30° view angle, rWLC) in 30 interventions. Subsequently, the comparison was transferred to in vivo n = 21 interventions. A validated usability score (System Usability Scale, SUS) as well as physician and patient-related outcomes were assessed using Likert-scale-based questionnaires. Intra- and postinterventional complications were recorded according to the Clavien-Dindo classification. RESULTS: The ex vivo evaluation showed a significant superiority of ECAM-WLC in 4 of 6 endoscopic tasks. Noteworthy is the lower pressure on the bladder neck due to the endoscopesalteration of the endoscope (4/60 vs 17/60, P <.0001) and a more precise imaging of all bladder regions (22/30 vs 30/30, P = .046), including the anterior wall (0/30 vs 28/30, P <.0001). In vivo, surgeons rated the ECAM-WLC with an "excellent" SUS of 86.79%, also expressing that ECAM-WLC would enhance bladder surface visualization (4.52/5.0 ± 0.51), with a preferred use for ECAM-WLC during their next cystoscopy (4.62 ± 0.50). Patients reported ECAM-WLC to be less painful (4.5/5.0 ± 0.84) compared to rWLC. No intervention-related complications were observed. CONCLUSION: ECAM-WLC is a safe and accessible procedure that could improve conventional diagnostic WLC by combination of the advantages of fWLC and rWLC.

Use of Artificial Intelligence for Medical Literature Search: Randomized Controlled Trial Using the Hackathon Format.

BACKGROUND: Mapping out the research landscape around a project is often time consuming and difficult. OBJECTIVE: This study evaluates a commercial artificial intelligence (AI) search engine (IRIS.AI) for its applicability in an automated literature search on a specific medical topic. METHODS: To evaluate the AI search engine in a standardized manner, the concept of a science hackathon was applied. Three groups of researchers were tasked with performing a literature search on a clearly defined scientific project. All participants had a high level of expertise for this specific field of research. Two groups were given access to the AI search engine IRIS.AI. All groups were given the same amount of time for their search and were instructed to document their results. Search results were summarized and ranked according to a predetermined scoring system. RESULTS: The final scoring awarded 49 and 39 points out of 60 to AI groups 1 and 2, respectively, and the control group received 46 points. A total of 20 scientific studies with high relevance were identified, and 5 highly relevant studies ("spot on") were reported by each group. CONCLUSIONS: AI technology is a promising approach to facilitate literature searches and the management of medical libraries. In this study, however, the application of AI technology lead to a more focused literature search without a significant improvement in the number of results.

Current Standards in the Endoscopic Management of Bladder Cancer: A Survey Evaluation among Urologists in German-Speaking Countries.

INTRODUCTION: To assess the current diagnostic, treatment, and documentation strategies for bladder cancer (BC) in German-speaking countries. MATERIALS AND METHODS: A 14-item web-based survey was distributed among members of the German, Austrian, and Swiss Associations of Urology, addressing physicians who perform cystoscopies and transurethral resection of bladder tumors (TURB). RESULTS: The survey was responded to by 308 of 5,564 urologists with a mean age of 49.5 years (response rate: 5.5%). The majority of participants (57.3%) practice in an outpatient setting. White light cystoscopy only is used by 60.2%, with additional photodynamic diagnosis and narrow band imaging by 36.8 and 12.5%, respectively. Endoscopic findings are documented in written form by 93.5%, followed by image capture (33.7%) and a central data archive (20.8%). Inpatient hospital urologists document cystoscopic findings by freehand drawing (21.4 vs. 11.4%, p = 0.017), and with a fixed bladder scheme (31.3 vs. 7.4%, <0.05) significantly more frequently. Cystoscopic findings are mainly conveyed to other health professionals in written form (77.4%), and significantly more often by inpatient urologists (p < 0.05). CONCLUSIONS: Significant differences exist in the approach to documenting and communicating cystoscopic BC findings. Accurate graphic documentation of lesions, visualization of the mucosa's totality, and meticulous consultation of previous surgical reports require improvements to reduce recurrence and progression rates.

Analysis of Interfacial Effects in All-Solid-State Batteries with Thiophosphate Solid Electrolytes.

All-solid-state batteries (ASSBs) present a promising route toward safe and high-power battery systems in order to meet the future demands in the consumer and automotive market. Composite cathodes are one way to boost the energy density of ASSBs compared to thin-film configurations. In this manuscript, we investigate composites consisting of ß-Li3PS4 (ß-LPS) solid electrolyte and high-energy Li(Ni0.6Mn0.2Co0.2)O2 (NMC622). The fabricated cells show a good cycle life with a satisfactory capacity retention. Still, the cathode utilization is below the values reported in the literature for systems with liquid electrolytes. The common understanding is that interface processes between the active material and solid electrolyte are responsible for the reduced performance. In order to throw some light on this topic, we perform 3D microstructure-resolved simulations on virtual samples obtained via X-ray tomography. Through this approach, we are able to correlate the composite microstructure with electrode performance and impedance. We identify the low electronic conductivity in the fully lithiated NMC622 as material inherent restriction preventing high cathode utilization. Moreover, we find that geometrical properties and morphological changes of the microstructure interact with the internal and external interfaces, significantly affecting the capacity retention at higher currents.

Application of artificial neural networks for automated analysis of cystoscopic images: a review of the current status and future prospects.

BACKGROUND: Optimal detection and surveillance of bladder cancer (BCa) rely primarily on the cystoscopic visualization of bladder lesions. AI-assisted cystoscopy may improve image recognition and accelerate data acquisition. OBJECTIVE: To provide a comprehensive review of machine learning (ML), deep learning (DL) and convolutional neural network (CNN) applications in cystoscopic image recognition. EVIDENCE ACQUISITION: A detailed search of original articles was performed using the PubMed-MEDLINE database to identify recent English literature relevant to ML, DL and CNN applications in cystoscopic image recognition. EVIDENCE SYNTHESIS: In total, two articles and one conference abstract were identified addressing the application of AI methods in cystoscopic image recognition. These investigations showed accuracies exceeding 90% for tumor detection; however, future work is necessary to incorporate these methods into AI-aided cystoscopy and compared to other tumor visualization tools. Furthermore, we present results from the RaVeNNA-4pi consortium initiative which has extracted 4200 frames from 62 videos, analyzed them with the U-Net network and achieved an average dice score of 0.67. Improvements in its precision can be achieved by augmenting the video/frame database. CONCLUSION: AI-aided cystoscopy has the potential to outperform urologists at recognizing and classifying bladder lesions. To ensure their real-life implementation, however, these algorithms require external validation to generalize their results across other data sets.

Efficacy and safety of aquablation of the prostate for patients with symptomatic benign prostatic enlargement: a systematic review.

PURPOSE: The aim of this systematic review is to summarize the contemporary literature on aquablation and evaluate its safety and efficacy for the treatment of symptomatic BPE. EVIDENCE ACQUISITION: A systematic search of English language literature was performed using the PubMed-MEDLINE and Web of Science libraries up to 24 July 2019 by combining PICO (patient population, intervention, comparison, and outcome) terms. We retrieved 16 studies, including 446 patients treated with aquablation eligible for data extraction and analysis. Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines were followed. EVIDENCE SYNTHESIS: We identified a randomized controlled trial (RCT) comparing aquablation to transurethral resection of the prostate (TURP) with 6-month, 1-year, and 2-year outcomes, three single-center and single-arm studies, three multicenter and single-arm studies, and five subgroup analyses. Aquablation significantly improved International Prostate Symptom Score (IPSS), IPSS-quality of life (IPSS-QoL), maximum urinary flow rate (Qmax) and post void residual (PVR) from baseline to last follow-up in all prospective studies. At 2-year follow-up, aquablation showed non-inferior symptom relief compared to TURP, with a lower risk of anejaculation favoring aquablation and no significant differences regarding Clavien-Dindo events. Although a significant hemoglobin drop was reported in all aquablation single-arm studies and when compared to TURP, it did not translate into increased transfusion rates. CONCLUSIONS: Data from the WATER trial demonstrates that aquablation is comparable to TURP in effectively improving symptom scores and functional parameters related to BPE and bladder outlet obstruction. The evidence provided supports the safety of aquablation assessed by procedure-related adverse events.

Thermal effects of Ho:YAG laser lithotripsy during retrograde intrarenal surgery and percutaneous nephrolithotomy in an ex vivo porcine kidney model.

PURPOSE: To evaluate the thermal effect of high-power holmium:yttrium-aluminum-garnet (Ho:YAG) laser lithotripsy in flexible/semirigid ureteroscopy (fURS/sURS) and percutaneous nephrolithotomy (PNL) in a standardized ex vivo porcine kidney model with real-time temperature assessment. METHODS: The experimental setup consisted of three models designed to evaluate the thermal effects of Ho:YAG laser lithotripsy in fURS, sURS and PNL, respectively. In all setups, a postmortem porcine kidney was placed in a 37 °C water bath. Three thermocouples were inserted into the renal parenchyma while a flexible thermocouple was placed 3-4 mm proximal to the laser fiber to measure temperature variations in the collecting system. The thermal impact was evaluated in relation to laser power between 5 and 100 W and various irrigation rates (37 °C, 0-100 ml/min). RESULTS: In all three experimental setups, sufficient irrigation was required to prevent potentially damaging temperatures into the renal pelvis and parenchyma. Even 5 W in fURS can lead to a potentially harming temperature rise if insufficient irrigation is applied. Particularly, high-power settings ≥ 30 W carry an elevated risk for critical temperature rises. The results allow the definition of a specific irrigation threshold for any power setting to prevent critical temperatures in the present study design. CONCLUSIONS: Ho:YAG laser lithotripsy bears the risk of thermal damages to the urinary tract even at low-power settings if inadequate irrigation is applied. Sufficient irrigation is mandatory to perform safe Ho:YAG laser lithotripsy. Based on the results, we developed a formula calculating the approximate ΔT for irrigation rates ≥ 30 ml/min: ΔT = 15 K × (power [W]/irrigation [ml/min]).

Current European Trends in Endoscopic Imaging and Transurethral Resection of Bladder Tumors.

Purpose: The aim of this survey was to obtain an overview of current European standards in the endoscopic visualization and management of bladder tumors. Methods: An online survey was launched in July 2018 for a duration of 4 months. It was distributed to all members of the European Association of Urology (EAU) and included 23 questions divided into 3 thematic sections: general information, white light cystoscopy (WLC) and imaging, and transurethral resection of bladder tumor (TURBT) techniques. Results: Responses of 222 participants were included for analysis. The majority of physicians were between 30 and 40 years of age (48.2%, n = 107) and performed over 50 TURBT per year (52.2%, n = 115). Overall, 52.3% (n = 116) reported WLC findings in written form only, 23.8% (n = 53) added endoscopic footage, and 79.2% (n = 176) considered preliminary WLC/TURBT reports before performing a subsequent bladder intervention. About half of the participants (50.5%, n = 104) used additional tumor visualization methods (aTVMs), but aTVMs were utilized by a greater proportion of physicians from Western countries (58.1%, n = 90) compared with developing countries (20.0%, n = 7). Photodynamic diagnosis was the predominant aTVM technique employed (43.8%, n = 60). Bipolar current was the most common technique for TURBT (46.6%, n = 149). Most urologists in this study occasionally utilized techniques like resections in fractions (80%, n = 161) or en bloc resection (87.2%, n = 182). A repeated TURBT was performed when no muscle was found in the specimen (70.6%, n = 149) and/or if the tumor was stage pT1 (72.0%, n = 152) or high grade (63.0%, n = 133). Conclusion: Implementation of resection techniques or repeated TURBT within EAU guidelines is promising, but it can be further challenged. For example, WLC/TURBT reporting should be improved since urologists consistently consider previous documentation. Given the moderate application rate of aTVMs, an attempt to increase its utilization would lead to a better assessment of its potential benefit.