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Objectives: The Thulium Fiber Laser (TFL) is studied as an alternative to the holmium:yttrium-aluminium-garnet (Ho:YAG) laser for lithotripsy, with the advantage of an induced bubble stream (IBS). ...

To explore the risk of encrustation and biofilm formation for silicone ureteral stents compared to percuflex polymer stents, through a randomized multicenter study. Design, setting and participants: A Multicenter, prospective, randomized, single blind, comparative study of hydrocoated silicone stent (Coloplast Imajin® hydro) versus Percuflex™ Plus stent (Boston Scientific), in 141 patients treated by flexible URS for a kidney stone. The study had ethical committee approval in the respective hospitals. Outcome measurements and statistical analysis: Endpoints related to encrustation were biofilm formation and mineral encrustation after a period of 3-week indwelling time. They were evaluated at removal through a scoring scale of ureteral stents encrustation, infrared spectroscopy and optical microscopy of inner and outer surfaces of tips, angles and along the stent’s body. Comparison was performed using ANOVA. 119 stents were available after removal for analysis, 56 in the silicone and 63 in the Percuflex TM Plus group. Mean dwelling duration was 21.8 days for silicone, 22.1 days for PercuflexTM Plus. There was significantly more biofilm on Percuflex™ Plus compared to silicone (1.24 ± 0.08 vs 0.93 ± 0.09, p = 0.0021), and more mineral encrustation (1.22 ± 0.10 vs 0.78 ± 0.11, p = 0.0048), respectively. This multicenter randomized study shows that silicone-hydrocoated stents are less prone to encrustation than PercuflexTM Plus after a 3-week dwelling period and confirms the low encrustation potential of silicone.

Objective: To compare whether the outcomes of ultrasound-guided access percutaneous nephrolithotomy (USGA-PCNL) are similar to standard fluoroscopy-guided access percutaneous nephrolithotomy (FGA-P...

A recently introduced device (LithoVue Empower™ or LE, Boston Scientifics, USA) allows the surgeon to directly control the stone-retrieving basket without the need of an assistant during flexible ureteroscopy. We aimed to evaluate the stone-retrieval performance of this device. We used a bench-training model for flexible ureteroscopy, the Key-box (K-Box®, Porges-Coloplast, France), to compare the LE configured with a 1.9F stone-retrieval tipless basket (ZeroTip™, Boston Scientific, USA) and a traditional assistant-maneuvered 1.9F stone-retrieval tipless basket. Seven experienced endo-urologists and seven residents-in-training retrieved a fake stone from three different renal cavities of the K-Box with increasing access complexity first with the traditional basket and then with the LE device. We recorded retrieval time and all the operators filled in the NASA Task Load Index (TLI) for the self-evaluation of their performance. We then compared the use of LE in terms of retrieval time, failure rates, and NASA-TLI scores. Stone retrieval times and failure rates were similar according to the retrieval technique, although residents had non-statistically significant shorter times with the LE. NASA-TLI scores revealed lower frustration (p = 0.03) when LE was used by experienced urologists as compared to the traditional basketing. When stratifying the analyses according to surgical experience, fully trained urologists performed faster stone retrieval and showed lower effort scores than residents-in-training (p

To compare intrapelvic pressure (IPP) levels achieved during f-URS, mini-PCNL, standard PCNL, and endoscopic combined intrarenal surgery in a kidney model. A silicone model simulating the complete urinary tract was used for all the experiments. We compared: a 9.5Fr f-URS, a 12Fr mini-nephroscope and a 26Fr nephroscope. The irrigation pressure was set at 40 and 193 cmH2O. We compared: f-URS-S ± ureteral access sheath (UAS, 10/12Fr, 11/13Fr, 12/14Fr) ± 273 μm laser fiber, Mini-PCNL with different sizes of operating sheath (15/16Fr, 16.5/17.5Fr, 21/22Fr) ± 365 μm laser fiber, Standard PCNL with an operating sheath of 30Fr ± Lithotripter LithoClast Master 11.4Fr. f-URS: IPP values ranged between 1.4 and 46.2 cmH2O. Factors reducing IPP were an irrigation pressure at 40 cmH2O, an occupied working channel, and the use of a UAS except with the 10/12Fr at 193 cmH2O. Mini-PCNL: IPP values ranged between 2.4 and 39.7 cmH2O. Factors reducing IPP were irrigation pressure at 40 cmH2O, a large operating sheath (> 15/16Fr). The occupation of the working channel did not affect the IPP at 40 cmH2O, while it decreased at 193 cmH2O. Standard PCNL: IPP values ranged between 1.4 and 7.3 cmH2O. Occupancy of the working channel did not affect IPP at 40 cmH2O, while it increased at 193 cmH2O. We recorded for the first time IPP values according to different endourological techniques and configurations. IPP never exceed 50 cmH2O irrespectively of the assessed technique/setup. The factors reducing IPP were a low irrigation pressure (40 cmH2O), the use of a UAS or a working sheath appropriate to the diameter of the endoscope, as well as the occupation of the working channel in the case of f-URS.

Objectives To evaluate the risk of contracting severe COVID‐19, defined as COVID‐19 specific intensive care unit (ICU) admission or death, for patients undergoing urological surgery during the epidemic. To define consequences of receiving surgery for COVID‐19 patients. Patients and Methods This is a multicenter observational cohort study. Every patient receiving a urological procedure in Paris academic urological centers during the 4 initial weeks of surgical restrictions were included. Their status was updated minimum 3 weeks after the procedure. The main outcomes were the COVID‐19 specific ICU admission and death. Statistics were mostly descriptive. The Post‐operative COVID‐19 confirmed group was compared with non‐COVID patients using Chi‐square tests for categorical and Wilcoxon test tests for continuous variables. Results During the 4‐week period, 552 patients received surgery within 8 centers. At follow‐up, 57 (10%) patients were lost. Among the 11 preoperative COVID‐19 cases, one remained in ICU, no new admission, and no death. For the non‐COVID patients, 57 (12%) developed COVID‐related symptoms; only one case (0.2%) required COVID‐19 specific ICU and 3 (0.6%) patients died of COVID‐19 after surgery. Conclusions Performing urological surgery during the COVID‐19 epidemic peak has a limited impact on ICU admissions but presents a real (0.6%) risk of specific mortality. Surgical activities should be maintained according to this risk.

To estimate the total energy needed to ablate 1mm3 of stone volume (Joules/mm3) during flexible ureteroscopic lithotripsy using a low-power Ho:YAG laser device, as a proxy of lithotripsy efficacy. We selected 30 patients submitted to flexible ureteroscopy for renal stones whose volume was bigger than 500 mm3. A 35 W Ho:YAG laser (Dornier Medilas H Solvo 35, Germany) was used for every procedure with a 272 µm laser fiber. We recorded laser parameters, the total energy delivered by the laser fiber, the time from the first laser pulse until the last one (lithotripsy time), and the active laser time as provided by the machine. We then estimated J/mm3 values and determinants, along with ablation speed (mm3/s), and laser activity (ratio between laser active time and lithotripsy time). Median (IQR) stone volume and stone density were respectively 1599 (630–3502) mm3 and 1040 (753–1275) Hounsfield units (HU). In terms of laser parameters, median (IQR) energy and frequency were 0.6 (0.4–0.8) J and 15 (15–18) Hz. Median (IQR) total delivered energy and lithotripsy time were 37,050 (13,375–57,680) J and 68 (36–88) min, respectively. Median (IQR) J/mm3 and ablation speed were, respectively, 19 (14–24) J/mm3 and 0.7 (0.4–0.9) mm3/s. The laser was active during 84% (70–95%) of the total lithotripsy time. HU density > 1000 was associated with reduced efficacy. It is possible to perform laser lithotripsy using a low-power laser device with a virtually continuous laser activity. The estimation of the pre-operative parameters as well as the J/mm3 values are fundamental for a proper pre-operatory planning.

Objective To investigate the effects of laser temporal pulse shaping of the super-pulse thulium fibre laser (SPTFL) and to compare these in controlled in vitro conditions with various holmium: yttrium aluminium garnet (Ho:YAG) pulse delivery modes. Materials and methods The SPTFL (Urolase SP, IRE-Polus, Fryazino, Russia), with an emission wavelength of 1.94 μm, and a Ho:YAG laser (P120H; Lumenis, Yokneam, Israel) with Moses technology were compared. Pulse shape, stone retropulsion and ablation efficiency were evaluated using BegoStones and compared for each laser mode: short (SP), long (LP), and Moses pulse (MP) for Ho:YAG, regular pulse (RP) and dual pulse (DP) for SPTFL. Results The Ho:YAG SP mode exhibited an asymmetrical pulse shape, with a steep leading slope and a much more gradual trailing slope, without any flat section. Pulses generated by the SPTFL were significantly longer and therefore had lower peak power than those generated by the Ho:YAG laser at equivalent energy settings. Retropulsion for the holmium:YAG LP and MP modes was similar and lower than that for the SP mode, but higher than for the SPTFL (all P ≤ 0.02), with an average stone displacement approximately four times and two times lower for SPTFL as compared to the Ho:YAG laser. Comparison of ablation volumes indicated that the SPTFL induced significantly higher (twofold) ablation than the Ho:YAG laser. Conclusions The magnitude and initial velocity of stone retropulsion decreased with longer pulse duration and lower pulse peak power, without sacrificing ablation efficiency. These observations are manifest when comparing the Ho:YAG laser with the SPTFL. The novel SPTFL provides greater versatility and control of pulse variables than the Ho:YAG laser. Further clinical investigation of practical benefits achievable with pulse-shaping SPTFL modes is warranted.

To evaluate the feasibility of measuring the intrapelvic pressure (IPP) during f-URS with a wire including a pressure sensor and to assess IPP profiles during the procedure. Patients undergoing f-URS for stone disease were recruited. A wire with pressure sensor was placed in the renal cavities to measure IPP. For these cases, either no ureteral access sheath (UAS) or 10/12 or 12/14-Fr UASs were used according to surgeon discretion. Irrigation was ensured by a combination of a continuous pressure generator set at 80 cmH2O and a hand-assisted irrigation system providing on-demand forced irrigation to provide proper visibility. Pressures were monitored in real time and recorded for analysis. Four patients undergoing five f-URS were included. IPP monitoring was successful in all patients. Mean baseline IPP was 6 cmH2O. During f-URS with only the endoscope in the renal cavities and irrigation pressure set at 80 cmH2O without any forced irrigation, the mean IPP was 63 cmH2O. Mean IPP during laser lithotripsy with the use of on-demand forced irrigation was 115.3 cmH2O. The maximum pressure peaks recorded during this therapeutic period using forced irrigation ranged from 289.3 to 436.9 cmH2O. High IPP levels may be achieved during f-URS with on-demand irrigation systems. The impact of these high pressures on the risk of complications and long-term consequences still need to be evaluated adequately. But, in this preliminary pilot study, IPP could be reliably and conveniently monitored and recorded using a wire with a digital pressure sensor.

To evaluate whether stone dust can be obtained from all prevailing stone composition types using the thulium fiber laser (TFL) for lithotripsy. Where applicable, stone dust was further characterized by morpho-constitutional analysis. Human urinary stones were submitted to in vitro lithotripsy using a FiberLase U2 TFL generator with 150 µm silica core fibers (IPG Photonics®, IPG Medical™, Marlborough, MA, USA). Laser settings were 0.05 J, 320 Hz and 200 μs. A total of 2400 J were delivered to each stone composition type. All evaluated stones had a > 90% degree of purity (calcium oxalate monohydrate, calcium oxalate dihydrate, uric acid, carbapatite, struvite, brushite and cystine). Spontaneously floating stone particles were considered as stone dust and collected for analysis by scanning electron microscopy and Fourier transform infrared spectroscopy. Stone dust could be retrieved from all evaluated urinary stones after TFL lithotripsy. Most stone dust samples revealed changes in crystalline organization, except for calcium oxalate monohydrate and carbapatite, which conserved their initial characteristics. Mean maximal width of stone dust particles did not exceed 254 µm. The TFL is capable to produce stone dust from all prevailing stone types. Morpho-constitutional changes found in stone dust suggest a photothermal interaction of laser energy with the stone matrix during TFL lithotripsy.

To propose a size-related definition of stone dust produced by lithotripsy of urinary stones. Stone dust was defined as particles small enough to adhere to the following criteria: (1) spontaneous floating under 40 cm H2O irrigation pressure; (2) mean sedimentation time of > 2 s through 10 cm saline solution; (3) fully suitable for aspiration through a 3.6 F working channel. Irrigation, sedimentation, and aspiration tests were set up to evaluate each criterion. Primary outcome was particle size limit agreeing with all three criteria. Stone particles with a given size limit (≤ 2 mm, ≤ 1 mm, ≤ 500 µm, ≤ 250 µm, ≤ 125 µm and ≤ 63 µm) were obtained from laser lithotripsy, including samples from prevailing stone types: calcium oxalate monohydrate, calcium oxalate dihydrate, uric acid, carbapatite, struvite, brushite, and cystine. All particles ≤ 250 µm from all stone types were in agreement with all three criteria defining stone dust, except for struvite where size limit for a positive irrigation and sedimentation test was ≤ 125 µm. A size limit of ≤ 250 µm seems to generally adhere to our definition of stone dust, which is based on floating and sedimentation proprieties of stone particles, as well as on the ability to be fully aspirated through the working channel of a flexible ureteroscope.

Holmium:YAG(Ho:YAG) is currently the standard for lithotripsy. Superpulsed Thulium Fiber Laser(TFL) has been evaluated as an alternative for lithotripsy, using laser fibers with core-diameters(CDF) down to 50 µm and additional available settings suitable for “dusting” technique. This in-vitro study compared ablation rates, fissures and fragments’ size with 150µmCDF or 272µmCDF with different laser settings using TFL and Ho:YAG. 150CDF and 272CDF were compared using three settings for TFL “fine dusting”(FD:0.15 J/100 Hz); “dusting”(D:0.5 J/30 Hz); “fragmentation”(Fr:1 J/15 Hz) and Ho:YAG(D and Fr). An experimental setup consisting of immerged 10 mm cubes of artificial hard(H) or soft(S) stone phantoms was used with a 20 s’ lasing time and a spiral trajectory, in contact mode. Fragments (acquired through sieves) and stones were observed under optical microscopy before three-dimensional scanning to measure fragments and fissures(DOF) mean diameters and ablation volumes. Ablation volumes in with 150CDF-TFL and 272CDF-TFL were higher than those for 272CDF-Ho:YAG in both “dusting” (twofold and threefold) and “fragmentation”(1,5-fold and twofold). “Fine dusting” ablation rates with 150CDF-TFL and 272CDF-TFL were respectively at least 1,5-fold and twofold higher than those for 272CDF-Ho:YAG in “dusting”. 150CDF produced significantly smaller DOF than 272CDF in all settings against S and H except in fragmentation. 150CDF produced lower fragments’ diameter than 272CDF in all settings except dusting. These preliminary studies demonstrate that at equal settings and CDF, TFL ablation rates are at least two-fold higher than those with Ho:YAG. 150CDF produces smaller fissures and fragments (that meets the definition of “dusting” lithotripsy) than 272CDF and higher ablation volumes than Ho:YAG.

Objective: To define the role of ureteroscopy for treatment of staghorn calculi. Methods: A systematic review was conducted using the Scopus and Medline databases. Original articles and systematic reviews were selected according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Only studies relating to the role of ureteroscopy for treatment of staghorn calculi were included. Results: In five studies on ureteroscopic monotherapy, stone-free rate (SFR) ranged from 33% to 93%, with a maximum four ureteroscopy sessions per patient and no major complications. Endoscopic combined intrarenal surgery (ECIRS) was compared with percutaneous nephrolithotomy (PNL) in two studies and reached significantly higher SFR (88%–91% vs. 59%–65%) and lower operative times (84–110 min vs. 105–129 min). The role of salvage ureteroscopy for residual stones after primary PNL has been highlighted by two studies with a final SFR of 83%–89%. One study reported on the feasibility of ureteroscopy for ureteral stones and same-session PNL for contralateral staghorn calculi, with a SFR of 92%. Conclusion: Ureteroscopy plays a pivotal role in the setting of a combined approach to staghorn calculi. Ureteroscopy is also particularly suitable for clearance of residual stones. In specific cases, ureteroscopy may become the sole applicable therapeutic option to staghorn calculi. Technological advances and refinement of techniques suggest a major role of ureteroscopy for staghorn calculi treatment in close future. Keywords: Staghorn calculi, Ureteroscopy, Percutaneous nephrolithotomy, Combined approach, Intrarenal surgery, Simultaneous bilateral endoscopic surgery

Resume But Identifier les causes d’hospitalisation prolongee chez les patients traites par ureteroscopie souple (URS-S). L’objectif secondaire a ete d’identifier des facteurs predictifs de complication. Materiel Une etude de cohorte retrospective monocentrique a ete menee entre janvier 2011 et decembre 2015. Ont ete inclus tous les patients consecutifs traites par URS-S dans le cadre d’une intervention programmee, quelle que soit l’indication, durant la periode etudiee ET restes hospitalises au moins une journee en plus de la duree d’hospitalisation postoperatoire traditionnelle de notre centre (> j1). Une analyse multivariee a ete realisee pour rechercher les facteurs predictifs d’hospitalisation prolongee. Resultats Au total, 272 patients ont ete inclus dans notre analyse. La duree mediane d’hospitalisation postoperatoire etait de deux jours [2–18]. 47 % des patients sortis a plus de j1 n’avaient aucune complication. Parmi eux, 56 % etaient restes pour surveillance simple decidee par le chirurgien sans qu’aucun traitement specifique n’ait ete introduit et 52 % pour poursuite d’une antibiotherapie par voie intraveineuse initiee en preoperatoire. Parmi les 144 patients restants et ayant eu une complication, 85,4 % (123/144) avaient une complication mineure (Clavien 1 ou 2). En analyse multivariee, les facteurs predictifs d’avoir une hospitalisation prolongee (sortie > j1) etaient un antecedent neurologique (paraplegie, spina bifida, sclerose en plaque) avec un odds ratio de 4,39 [1,7 ; 11,4] Conclusion Les causes d’hospitalisation prolongee etaient principalement les comorbidites. Un nombre non negligeable de patients etaient restes hospitalises sans complication. L’identification des facteurs predictifs de complications et d’hospitalisation prolongee peut permettre une meilleure selection des patients eligibles a la chirurgie ambulatoire et selectionner ceux pour qui l’hospitalisation traditionnelle reste recommandee. Niveau de preuve 3.

With an increase in the number of ureteroscopy (URS) procedures, URS is now performed more widely and is becoming a standard procedure for all urologists. There is also a rise in the complexity of these procedures and URS is now offered for treatment of stones as well as for diagnosis and treatment of urothelial tumours. We wanted to provide a 'pictorial review' of the 'tips and tricks' of URS, as the finer and technical details are often easier to understand and remember with images rather than through textual explanations.

Objective To assess the intermediate- and long-term effect of high-grade ureteral injuries from ureteral access sheaths. Methods Patients undergoing ureteroscopy for upper tract calculi were prospectively enrolled at 2 sites from 2010 to 2015. A 12/14 French sheath was used and the ureter was inspected with a flexible ureteroscope during withdrawal of the sheath and recorded. The videos were then evaluated by 2 blinded endourologists, and any injuries were graded per the Traxer ureteral injury scale. Only high-grade injuries were included. The primary endpoint was defined as ongoing hydronephrosis without an obstructing stone on follow-up imaging indicating a ureteral stricture. Logistic regression analysis was used to assess the relationship between hydronephrosis, ureteral injury, and other patient variables. Results Fifty-six patients were identified with high-grade ureteral injuries. Sixteen patients (28.6%) were female. Median age was 56.4 years (range 14-85). Median follow-up was 35.8 months (range 0-88). Three patients (5.5%) had hydronephrosis on follow-up imaging, only 1 of whom developed a de novo ureteral stricture. On univariate analysis, hydronephrosis was associated with a shorter stent duration (P = .11) and older age (P = .17). Conclusion Endoscopically identified high-grade ureteral lesions following ureteral access sheath placement do not lead to clinically significant sequelae on intermediate term follow-up, with a stricture rate comparable to those without visible injuries of 1.8%.

To present attributes of currently available flexible ureteroscopes to define the best flexible ureteroscope for upper tract urothelial carcinoma (UTUC) treatment. Scopus and Medline databases were searched for articles relating to performance of flexible ureteroscopes. A consensus for final inclusion of articles judged to be relevant for UTUC treatment was reached between the authors. Instrument characteristics were extracted from manufacturers’ product brochures. Smaller cross-sectional size of instruments is associated with increased probability for successful primary access to the upper urinary tract. The smallest flexible ureteroscopes are fiberoptic scopes. Smaller ureteroscopes also allow comparatively increased irrigation flow at constant intrarenal pressure. Digital flexible ureteroscopes achieve superior image quality compared to their fiberoptic counterparts, at the price of lower end-deflection ability. Image enhancement technologies such as narrow-band imaging (NBI), photodynamic diagnosis (PDD) and Image 1-S (formerly SPIES) are based on subjective image interpretation by the operator. NBI and PDD significantly increase tumor detection rate. The highest subjective image quality score of the Image 1-S technology is reached by the “Clara + Chroma” mode. Single-use ureteroscopes offer potential advantages over reusable scopes, including sterility, absence of contamination, immediate availability and exemption of previous instrument wear. Miniaturization, digital image caption and image enhancement technologies seem to be the major determinants defining the best flexible ureteroscope for UTUC treatment. The impact of further factors, such as distal tip design, torque, working channel position, risk of contamination, as well as upcoming technological innovations should be evaluated in randomized controlled trials.

Objectifs L’etude in vitro de la lithotritie laser (LL) utilise des calculs humains (CH) ou synthetiques (CS). Devant l’augmentation de la pulverisation laser (Dusting), peu d’echantillons humains sont disponibles. Les CS sont donc privilegies, confectionnes par melange d’eau et de plâtre, avec la problematique de leur rehydratation lors des LL. L’objectif etait de comparer les volumes d’ablation (VA) entre CS homogenes (CSHo) ou heterogenes(CSHe), et par rapport au poids ablate (PA). Methodes Les CSHo et CSHe durs (COM) ou tendre (UA) etaient confectionnes par melange de BegostonePlus (Bego®) et brassage lent ou rapide avec exsufflation, respectivement. Des fibres laser (Boston Scientific®) connectees au TFL (IPG Photonics®) 50 W (272 μm ou 150 μm) ou au MH1 Ho :YAG 30 W (Rocamed®) (272 μm) ont ete utilisees selon trois parametres laser (« fine dusting » [FD : 0,15 J/100 Hz], « dusting » [D : 0,5 J/30 Hz] et « fragmentation » [Fr : 1 J/15 Hz]). Une emission laser de vingt secondes etait realisee respectant une spirale de rayon 4 mm en contact avec les CS cubiques de 10 mm, prealablement peses et immerges. Apres sechage, les calculs etaient peses et scannes (Quantum FX, Perkin Elmer). Les volumes d’ablation etaient mesures par segmentation (3DSlicer [NIH]) ( Fig. 1 ). La correlation PA-VA (cPA-VA) etait evaluee pour chaque groupe. Resultats Avec les CSHe, les VA en Dusting etaient quatre et trois fois superieurs avec le TFL par rapport au Ho :YAG contre COM (p Tableau 1 ). Avec les CSHo cette difference n’etait plus significative contre UA en Dusting (p = 0,08) et Fragmentation (p = 0,09). L’utilisation des CSHo etait associee a des differences non significatives entre TFL-150 μm et TFL-272 μm, et entre TFL-150 μm et Ho :YAG-272 μm. La cPA-VA etait superieure en cas de CSHo par rapport au CSHe (0,853 versus 0,428, p Tableau 2 ). Si la cPA-VA etait acceptable en cas de COM (CSHo ou CSHe), il n’est pas possible d’utiliser l’approximation du VA par le PA en cas d’UA. Conclusion L’efficacite in vitro d’une LL est plus precise en utilisant les VA plutot que les PA. L’approximation du VA par le PA est acceptable et moins couteuse en cas de CSHo et dur (COM) bien que les calculs urinaires ressemblent plus aux CSHe (COM ou UA).

Context Morphoconstitutional analysis of urinary stones is perhaps the most important examination in the evaluation of a patient with urolithiasis. Objective A comprehensive stone classification system was developed in the early 1990s by Michel Daudon, which included the main types of stones and their possible physiopathogenic origin. Evidence acquisition A narrative review of the articles published about this classification was conducted, without time limit. Evidence synthesis Two analytical steps are needed for the classification process: the microscopic examination, which gives the stone morphology, and the physical analysis, which provides the stone constitution. Upon completion of a full analysis, knowledge of the principal crystal species of the stone is acquired. In addition, this analysis highlights the possible causes of the lithogenic process, taking in account less frequent, but severe, pathologies. Conclusions The aim of this report is to summarize the principal etiological causes for urinary stone formation thanks to the morphoconstitutional analysis and to present its contribution in the field of urinary stones. Patient summary We looked at all types of stones and found that their origin varies according to the underlying pathology of the patient.

There is currently insufficient in vivo evidence that high-power Ho:YAG lasers improve retrograde intrarenal surgery or the ablation efficacy. While prospective trials are awaited, a low-cost, silent, low-power Ho:YAG laser that requires only a standard electrical outlet is more than sufficient for retrograde intrarenal surgery.

Despite the worldwide spread of Ho:YAG lasers in urology departments, the physical principles behind their functioning may still seem obscure to many urologists. Moreover, a new laser source, the thulium fiber laser (TFL), was recently approved for stone lithotripsy. Here we describe the concepts of peak power and pulse modulation for laser lithotripsy, analyzing both Ho:YAG lasers and TFLs. Different pulse modalities are available for Ho:YAG lasers—long and short pulses and Moses technology—each with a different pulse shape and peak power. Lower peak power and a more rectangular pulse shape provide higher ablation efficiency and lower stone retropulsion. These characteristics are perfectly embodied by TFL, which shows the most effective ablation efficiency in laboratory studies. A long pulse is the most effective modality for Ho:YAG lasers. Moses technology, despite its promising rationale, is not superior to long-pulse mode. Clinical studies are needed in order to confirm these laboratory data. Patient summary: Laser lithotripsy is one of the main options for the treatment of urinary stones. The peak power and pulse modulation influence the choice of the optimal laser mode for the treatment of urinary stones. Thulium fiber lasers have shown the most favorable dusting profile in terms of both peak power and pulse modality in laboratory studies, but clinical evidence is still lacking. Peak power and pulse modulation influence choice of the optimal laser mode for the treatment of urinary stones. Thulium fiber lasers show the best profile in terms of both peak power and pulse modulation, although clinical studies are still awaited.

To define which long-term stent would work best in malignant ureteral obstruction (MUO) and benign ureteral obstruction (BUO), focusing on their mechanisms of action, price and insertion approach. A systematic review was developed using the MEDLINE and Scopus databases and in accordance with the PRISMA checklist. There were no language restrictions for the search. Studies describing the use of metallic ureteric stents for MUO and for BUO in humans were included. We analyzed five types of metallic stents (35 papers) and also the experience with the tumor and extra-anatomical stents. The Resonance, Memokath and Allium ureteral stents were found to be useful in BUO and MUO. The Uventa stent performed well in chronic ureteral obstruction. The Detour bypass stent was a recommended option in those patients who had complete obstruction of the ureter and were unfit for reconstructive surgery. There was no difference with regard to the insertion technique and both antegrade and retrograde approaches were equally successful. Although tumor stents showed a good performance, there were very few published studies on it. Metallic stents are a suitable option for MUO and BUO. When compared to standard double J stents, although they are relatively high priced, they show a financial benefit in the long-term. The Detour bypass stent seems to be an effective alternative for complete ureteral obstruction or patients unfit for surgery. Further prospective randomized studies should be done on the effectiveness of tumor stents versus metallic stents.

To explore the mechanisms behind the potential protective effect of coffee and tea consumption, regarding urinary stone formation, previously demonstrated in large epidemiological studies. A systematic review was performed using the Medline, Cochrane library (CENTRAL) and Scopus databases, in concordance with the PRISMA statement. English, French and Spanish language studies, regarding the consumption of caffeinated and decaffeinated coffee and tea, and the relationship to urinary stone formation were reviewed. Meta-analyses, systematic reviews, case reports and letters, unpublished studies, posters and comments abstracts were excluded. As per the inclusion criteria, 13 studies were included in the final review. The major findings show that caffeine increases urinary excretion of calcium, sodium and magnesium, in addition to a diuretic action with consumption > 300–360 mg (approximately four cups of coffee). Together with other components of coffee, this beverage might have potential protective effects against the formation of urinary stones. Tea exerts many protective effects against stone formation, through the accompanying water intake, the action of caffeine and the effects of components with antioxidant properties. Caffeine has a hypercalciuric effect, balanced partially by a diuretic effect which appears after consumption of large quantities of caffeine. The current available literature supports in general, a potentially protective role for tea against stone formation, mainly for green tea. Additional standardization in this field of research, through specification of tea and coffee types studied, and their respective compositions, is needed for further clarification of the relation between coffee, tea and urinary stones.

To explore the relationship between the consumption of coffee and tea with urolithiasis. We evaluated large epidemiological and small clinical studies to draw conclusions regarding their lithogenic risk. A systematic review was performed using the Medline and Scopus databases, in concordance with the PRISMA statement. English, French, and Spanish language studies regarding the consumption of caffeinated and decaffeinated coffee and tea, and the relationship to urinary stone disease were reviewed. Case reports and letters, unpublished studies, posters, and comments were excluded. As per the inclusion criteria, 13 studies were included in the final review. Most studies, including four large prospective studies and one meta-analysis, reported a reduced risk of stone formation for coffee and tea. Caffeine has a diuretic effect and increases the urinary excretion of calcium, but if these losses are compensated for, moderate caffeine intakes may have little or no deleterious effects. Green and Herbal teas infused for short time had low oxalate content compared to black tea. There is no evidence that moderate consumption of coffee raises the risk for stone formation in healthy individuals, provided the recommended daily fluid intake is maintained. The currently available literature supports in general a protective role for tea against the stone formation, mainly for green tea. However, heterogeneity of published data and lack of standardization needs to be addressed before final and clear conclusions can be given to patients and to the public in general.

Introduction Kidney Stone Calculator (KSC) est un outil que nous avons developpe pour mesurer le volume lithiasique total (VLT) et estimer la duree operatoire de lithotritie laser endocorporelle (LLE) au cours de l’ureterorenoscopie souple (URS-S), a partir du scanner abdominopelvien preoperatoire non injecte (TDM AP IV-). L’objectif de cette etude etait de realiser une evaluation preclinique et clinique de cet outil. Methodes Une base de donnees scanographiques (17) etait prealablement constituee : 9 calculs humains, 6 calculs synthetiques cubiques, 2 situations cliniques (calcul unique et coralliforme). Apres formation, les VLT etaient mesures en aveugle par trois operateurs (interne, urologue senior, ingenieur). Une analyse des coefficients de correlation inter-operateurs et de Kendall etait realisee. Fut conduite ensuite une etude clinique multicentrique prospective en double aveugle incluant des patients avec calculs renaux traites par URS-S avec LLE et TDM AP IV- preoperatoire dans 3 centres, entre janvier et mars 2020. Etaient collectees les caracteristiques demographiques, lithiasiques (diametre maximum, VLT, densite) et operatoires (materiel, duree et parametres de LLE avec laser Holmium :YAG, energie totale delivree, complications). Les durees de LLE effective (EfLLE) et estimee (EsLLE) par KSC ont ete comparees, ainsi que 5 facteurs influencant potentiellement cette estimation : calcul caliciel inferieur non relocalisable ou non relocalise, diametre de la gaine d’acces, mode de LLE et experience de l’operateur. Resultats Aucune difference significative n’etait retrouvee entre les operateurs (Op1-Op2 : p = 0,35, Op1-Op3 : p = 0,69, Op2-Op3 : p = 0,29). Une forte concordance inter-operateur etait retrouvee (Kendall : 0,98 et correlation Pearson : 0,99). Concernant l’evaluation clinique, 26 patients furent inclus dans trois centres, avec un âge median de 55,5 ans. Le sex-ratio etait de 2 hommes pour 1 femme, avec un IMC median de 28,7 kg/m2. Les patients presentaient un calcul unique, caliciel inferieur et une densite > 1000 UH dans 66 %, 42 % et 85 %, respectivement ( Tableau 1 ). Une difference mediane de 14 % (5,4–24,8) entre EsLLE et EfLLE etait constatee (p = 0,36), majoree en cas de calcul caliciel inferieur non relocalisable (p = 0,008), en mode Fragmentation ( Tableau 2 , Tableau 3 ). Le diametre de la gaine d’acces ureterale et l’experience de l’operateur n’influencaient pas significativement cette difference (p = 0,46 et p = 0,07, respectivement). L’energie par mm3 et le debit d’ablation medians etaient de 17,6 J/mm3 et 23,8 mm3/min, respectivement. Conclusion Kidney Stone Calculator est un outil de planification operatoire reproductible et fiable. Il permet d’estimer le VLT et la duree de LLE a partir du TDM AP IV- preoperatoire avec fenetrage osseux manuel sans prerequis. Les calculs caliciels inferieurs non relocalisables, le mode Fragmentation et l’experience moindre de l’operateur peuvent conduire a sous-estimer la duree de LLE. Une etude clinique sur un plus grand nombre de patients est necessaire pour valider ces resultats.

Introduction: Holmium:yttrium–aluminium–garnet (Ho:YAG) is currently the gold standard for lithotripsy for the treatment of all known urinary stone types. Stone composition and volume are major determinants of the lithotripsy. This in vitro study evaluated the required energy to ablate 1 mm3 of various stone types with different laser settings using Ho:YAG. Methods: 272 µm core-diameter laser fibers (Boston Scientific©) were connected to a 30 Watt MH1 Ho:YAG generator (Rocamed®). An experimental setup consisting of immerged human stones of calcium oxalate monohydrate (COM), uric acid (UA) or cystine (Cys) was used with a single pulse lasing emission (0.6/0.8/1 J), in contact mode. Stones were dried out before three-dimensional scanning to measure ablation volume per pulse (AVP) and required energy to treat 1 mm3 (RE). Results: All settings considered, ablation volumes per pulse (AVP) for COM were significantly lower than those for UA and Cys (p = 0.002 and p = 0.03, respectively), whereas AVP for Cys was significantly lower than those for UA (p = 0.03). The mean REs at 0.6 J pulse energy (PE) for COM, Cys and UA were 34, 8.5 and 3.2 J, respectively The mean REs at 1 J PE for COM, Cys and UA were 14.7, 6.4 and 2 J, respectively. At 0.6 J PE, RE for COM was more than tenfold and fivefold higher than those for UA and Cys, respectively. Conclusion: This in vitro study shows for the first time a volumetric evaluation of Ho:YAG efficiency by the ablation volume per pulse on human stone samples, according to various pulse energies. The REs for COM, UA and Cys should be considered in clinical practice. In vivo imaging was performed at Life Imag-ing Facility of Paris Descartes University (Plateforme Imageries du Vivant), supported by France Life Imaging (grant ANR-11-INBS-0006) and Infrastructures Biologies-Santé.

Objectifs La vitesse optimale de deplacement (VOD) de la fibre laser pour realiser la pulverisation lithiasique est une variable inconnue a ce jour, autant pour le laser thulium fibre (TFL) que pour le laser Holmium :YAG (Ho :YAG). L’objectif etait de determiner in vitro la VOD de la fibre laser lors d’une lithotritie endocorporelle en fonction des parametres laser avec le TFL et l’Ho :YAG, au moyen des volumes d’ablation (VA). Methodes Des fibres laser (Boston Scientific) de diametre 272 μm connectees au TFL (IPG Photonics) 50 W ou au MH1 Ho :YAG 30 W (Rocamed) ont ete comparees selon trois modes de lithotritie TFL (« fine dusting » [FD : 0,05–0,15 J/100–600 Hz], « dusting » [D : 0,5 J/30–60 Hz] et « fragmentation » [Fr : 1 J/15–30 Hz]) et deux modes Ho :YAG (« dusting » [D : 0,5 J/20 Hz] et « fragmentation » [Fr : 1 J/15 Hz]). Une emission laser de deux secondes etait realisee en contact avec des calculs synthetiques (Begostone) durs, en position statique ou avec un deplacement de 5, 10 ou 20 mm. Apres sechage, les calculs etaient scannes (Quantum FX, Perkin Elmer). Les VA etaient mesures par segmentation (3DSlicer [NIH]) ( Fig. 1 ). Resultats Quels que soient les parametres ou source laser, les VA dynamiques (VAD) etaient superieures aux VA statiques (VAS) (Tableau 1). En Dusting, les VAS et VAD etaient trois et quatre fois superieurs avec le TFL par rapport au Ho :YAG (p Tableau 1 ). Pour le TFL, les VODTFL etaient de 5 mm/s en Fine Dusting, Dusting et Fragmentation, sauf a 0,15 J-100 Hz (10 mm/s). Les profils de VOD entre TFL et Ho :YAG differaient, avec une VODTFL a 0,15 J-100 Hz identique a la VODHo :YAG a 0,5 J-20 Hz. A 50 mJ, la VODTFL etait proportionnelle a la frequence, toutefois non retrouvee a 0,15, 0,5 et 1 J ( Tableau 2 ). Conclusion Cette etude retrouve une VODTFL inferieure par rapport a la VODHo :YAG en Dusting, traduisant une potentielle utilisation plus aisee du TFL pour realiser une pulverisation optimale. La VOD semble d’avantage varier selon le couple energie-frequence, que selon la frequence seule. Que cela soit en position statique ou dynamique, les VATFL est 3 a 4 fois superieurs aux VAHo :YAG.

During the past 3 decades, the surgical management of kidney stones has undergone many technological advances and one is the development of the flexible ureteroscopy. The development of this instrument as well as ancillary equipment such as baskets, graspers, and others, and improvements in lithotripsy with Holmium: YAG laser have led to expand its indications with diagnostic and therapeutic management of medical issues of the upper urinary tract such as urolithiasis and urothelial tumors. The objective of this review is to describe its indications and results in the different scenarios for the treatment of urinary stones. Keywords: Ureteroscopy, Retrograde intrarenal surgery, Endourology, Urolithiasis

To evaluate a portable electronic pH meter and to put its accuracy in perspective with reagent strips read by a layperson, a healthcare professional, and an electronic reading device.Based on a preanalysis on 20 patients, a sample size of 77 urine aliquots from healthy volunteers was necessary to obtain sufficient study power. Measurements of urinary pH were obtained by use of reagent strips, a portable pH meter and a laboratory pH meter (gold standard). Reagents strips were read by a professional experienced in interpreting strips, a layperson, and an electronic strip reader. The mean matched pair difference between measurement methods was analyzed by the paired t-test. The degree of correlation and agreement were evaluated by the Pearson's correlation coefficient and Bland-Altman plots, respectively.The mean matched pair difference between the gold standard and all other pH measurement methods was the smallest with the portable electronic pH meter (bias 0.01, 95% confidence interval [CI] -0.07 to 0.08; p = 0.89), followed by strips read by a professional (bias -0.09, 95% CI -0.21 to 0.02; p = 0.10), layperson (bias -0.17, 95% CI -0.31 to -0.04; p = 0.015), and electronic strip reader (bias -0.29, 95% CI -0.41 to -0.16; p 0.001). The portable electronic pH meter achieved the highest Pearson's correlation coefficient and narrowest 95% limits of agreement, followed by strip interpretation by a professional, electronic strip reader, and layperson. To quantify the ability of pH measurement methods to correctly classify values within a predefined urinary pH target range, we performed classification tests for several stones. The portable electronic pH meter outperformed all other measurement methods for negative predictive values.Findings of this study support that the portable electronic pH meter is a reliable pH measuring device. It appears to be more accurate compared to reagent strips readings.

Purpose We tested the effects of tumor size, distribution and grade on progression-free survival in patients with upper tract urothelial carcinoma treated with flexible ureteroscopy with Ho:YAG laser photoablation. Materials and Methods Included in analysis were data on 92 consecutive patients with upper tract urothelial carcinoma treated with Ho:YAG laser photoablation from 2003 to 2015 at a single tertiary care referral center. Stringent followup was offered according to EAU (European Association of Urology) guidelines. Progression during followup was defined by tumor upgrading, distant metastases and/or a relapsing tumor that could not be completely removed with a conservative approach. Kaplan-Meier curves were used to assess the rate of disease progression according to tumor size (1 or less cm vs greater than 1 cm), tumor distribution (unifocal vs multifocal) and tumor grade (low vs high). Cox regression analysis was done to test the impact of clinical and pathological characteristics on the rate of progression-free survival. Results At a median followup of 52 months (IQR 27.8–76.4) the progression-free survival rate was 68% vs 72% in patients with a tumor size of 1 or less vs greater than 1 cm (p = 0.9), 72% vs 69% in patients with unifocal vs multifocal lesions (p = 0.6) and 75% vs 52% in patients with a low vs a high grade tumor (p = 0.03). On multivariable Cox regression analysis tumor grade at first treatment was the only independent predictor of disease progression (HR 5.16, 95% CI 1.19–22.26, p = 0.03). Conclusions High tumor grade independently decreased progression-free survival in patients with upper tract urothelial carcinoma treated with Ho:YAG laser photoablation. Tumor size greater than 1 cm and multifocality did not increase the risk of disease progression in patients treated conservatively with Ho:YAG laser photoablation.

To analyze the risk factors for laser fiber fractures when deflected to form a curve, including laser settings, size of the laser fiber, and the fiber bending diameter.Single-use 272 and 365 μm fibers (RocamedWith dusting settings, fibers broke more frequently at a curved diameter of 9 mm for both 272 and 365 μm fibers (p = 0.037 and 0.006, respectively). Using fragmentation settings, fibers broke more frequently at 12 mm for 272 μm and 15 mm for 365 μm (p = 0.007 and 0.033, respectively). Short pulse and high energy were significant risk factors for fiber fracture using the 365 μm fibers (p = 0.02), but not for the 272 μm fibers (p = 0.35). Frequency was not a risk factor for fiber rupture. Fiber diameters also seemed to be involved in the failure with a higher number of broken fibers for the 365 μm fibers, but this was not statistically significant when compared with the 272 μm fibers (p 0.05).Small-core fibers are more resistant than large-core fibers as lower bending diameters (9 mm) are required to break smaller fibers. In acute angles, the use of small-core fibers, at a low energy and long-pulse (dusting) setting, will reduce the risk of fiber rupture.

Resumen Introduccion La reaccion inflamatoria local despues de una biopsia prostatica (BP) puede influir de manera negativa en los resultados globales posprostatectomia radical. No hay evidencia suficiente en la literatura respecto al impacto del numero de punciones en los resultados posquirurgicos. Objetivos Determinar el impacto del numero de punciones de la BP en las complicaciones posquirurgicas y en el estado de los margenes operatorios. Material y metodos Se registraron prospectivamente 2.054 pacientes sometidos a prostatectomia radical asistida por robot (PRAR) en nuestra institucion. Se formaron 2 grupos de pacientes, en relacion con el numero de punciones en la BP (G1 ≤ 12 punciones; G2 > 12 punciones). Se evaluo por medio del analisis multivariable (modelos de regresion logistica) el impacto del numero de punciones en las complicaciones posquirurgicas. Resultados Se incluyeron 1.042 pacientes en el grupo 1 (≤ 12 punciones) y 1.012 pacientes en el grupo 2 (> 12 punciones). La tasa de complicaciones perioperatorias se incremento a medida que aumentaba el numero de punciones. (G1 6,4 vs. G2 8,5%; p = 0,03); no obstante, las complicaciones mayores (Clavien 3-4) fueron similares (G1 1,4 vs. G2 2,2%; p = 0,16). No hubo diferencia estadisticamente significativa respecto a los margenes quirurgicos positivos en ambos grupos (G1 11,8 vs. 9,98%; p = 0,2). El analisis multivariable (regresion logistica) demostro que el grupo 2 tenia un porcentaje un 39% mayor de experimentar complicaciones post-PRAR (OR 0,645). Conclusion El mayor numero de punciones (> 12) en la BP podria estar relacionado con mayor sangrado y complicaciones posquirurgicas despues de PRAR. Una cuidadosa evaluacion preoperatoria de los pacientes que se sometieron a biopsias o protocolos de saturacion multiple es obligatoria. La aplicacion de intervalos mas largos (> 6 semanas) entre la biopsia y la cirugia puede ser recomendable para minimizar los potenciales riesgos de complicaciones quirurgicas en los pacientes que pueden beneficiarse de PRAR. Otros estudios son todavia necesarios para confirmar estos resultados.

During endourological procedures, the eye of the urologist is exposed to hazards such as contact with body fluids and irrigation solutions as well as laser injury, and X-ray radiation absorption. The resulting potential injuries and damages to the eye have not been summarily reviewed to date. The objective was to review the different risks of exposure to the eyes of urologists during endourological procedures. The Medline database was searched for identification of studies on hazards to the eye of the endourologist. All articles published in English until September 2018 were considered. Twenty-three publications were included in this analysis. The incidence of eye contact with patient body fluids or irrigation solutions during endoscopic procedures ranged between 37.50 and 100%. Laser-induced eye injuries were reported in 37.9% of all kind of adverse events related to laser use in urology. The eye lens dose of radiation ranged from 0.04 to 1600 µSv per endourological procedures. While the risks of infection, laser injury, lens opacity and cataract are generally low, the wear of protective glasses is recommended. Lead glasses may protect against all these risks in case of Ho:YAG laser use with concomitant X-ray radiation. If Ho:YAG laser is used without any concomitant X-ray radiation, proper laser safety glasses or at least conventional eyeglasses should be recommended. When other types of laser are used, we recommend wearing laser eye protection glasses covering the adequate range of wavelength. For endourological procedures without laser use and X-ray radiation, specific protection devices such as goggles or face shields are recommended.

The aim of this paper was to give a complete overview of all published complications associated with ureteroscopy and their according management and prevention in current urological practice. This review was registered in PROSPERO with registration number CRD42018116273. A bibliographic search of the Medline, Scopus, Embase and Web of Science databases was performed by two authors (V.D.C. and E.X.K.). According to the Population, Intervention, Comparator, Outcome (PICO) study design approach and Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) standards, a consensus between these authors was found relating to the thematic structure of this review. Ureteral stent discomfort, ureteral wall injury and stone migration are the most frequently reported complications. The worst complications include urosepsis, multi-organ failure and death. Incidence rates on these and other complications varied extensively between the reviewed reports. Ureteroscopy seems to be associated with more complications than currently reported. The present overview may help urologists to prevent, recognize and solve complications of ureteroscopy. It may also stimulate colleagues to perform prospective studies using standardized systems for classifying complications. These are warranted to compare results among different studies, to conduct meta-analyses, to inform health care workers and to counsel patients correctly about possible risks of ureteroscopy.

Background: Single-use flexible ureterorenoscopes (fURSs) have been recently introduced aiming to offer solutions to the sterilization, fragility and cost issues of the reusable fURSs. In order to be a viable alternative, the single-use scopes must prove similar capabilities when compared to their reusable counterparts. The goal of our in-vitro study was to compare the current reusable and single-use digital fURSs regarding their deflection, irrigation and vision characteristics. Methods: We compared in-vitro 4 single-use fURSs-LithoVue (TM) (Boston Scientific, Marlborough, Massachusetts, USA), Uscope (TM) (Zhuhai Pusen Medical Technology Co. Ltd., Zhuhai, Guangdong Province, China), NeoFlex (TM) (NeoScope Inc, San Jose, California, USA) and ShaoGang (TM) (YouCare Technology Co. Ltd., Wuhan, China) versus 4 reusable fURSs-FLEX-Xc (Karl Storz SE & Co KG, Tuttlingen, Germany), URF- V2 (Olympus, Shinjuku, Tokyo, Japan), COBRA vision and BOA vision (Richard Wolf GmbH, Knittlingen, Germany). Deflection and irrigation abilities were evaluated with different instruments inserted through the working channel: laser fibres (200/273/365 mu m), retrieval baskets (1.5/1.9/2.2 Fr), guide wires [polytetrafluoroethylene (PTFE) 0.038 inch, nitinol 0.035 inch] and a biopsy forceps. A scoring system was designed to compare the deflection impairment. Saline at different heights (40/80 cm) was used for irrigation. The flow was measured with the tip of the fURS initially straight and then fully deflected. The vision characteristics were evaluated (field of view, depth of field, image resolution, distortion and colour representation) using specific target models. Results: Overall, the single-use fURSs had superior in-vitro deflection abilities than the reusable fURSs, in most settings. The highest score was achieved by NeoFlexT and the lowest by ShaoGang (TM). PTFE guide wire had most impact on deflection for all fURSs. The 200 mu m laser fibre had the lowest impact on deflection for the single-use fURSs. The 1.5 Fr basket caused the least deflection impairment on reusable fURSs. At the end of the tests, deflection loss was noted in most of the single-use fURSs, while none of the reusable fURSs presented deflection impairment. ShaoGang (TM) had the highest irrigation flow. Increasing the size of the instruments occupying the working channel led to decrease of irrigation flow in all fURSs. The impact of maximal deflection on irrigation flow was very low for all fURSs. When instruments were occupying the working channel, the single-use fURSs had slightly better in-vitro irrigation flow than the reusable fURSs. The field of view was comparable for all fURSs, with LithoVue (TM) showing a slight advantage. Depth of field and colour reproducibility were almost similar for all fURSs. ShaoGang (TM) and UscopeT had the lowest resolution. FLEX Xc had the highest image distortion while LithoVueT had the lowest. Partial field of view impairment was not for Uscope (TM) and ShaoGang (TM). Conclusions: In-vitro, there are differences in technical characteristics of fURSs. It appears that single-use fURSs deflect better than their reusable counterparts. Irrespective of deflection, the irrigation flow of the singleuse fURSs was slightly superior to the flow of the reusable fURSs. Overall, reusable fURSs had better vision characteristics than single-use fURSs. Further in-vivo studies might be necessary to confirm these findings.

International audience; Purpose: To evaluate how variable working distances between the laser fiber and the stone influence ablation volume. Methods: A laser fiber was fixed on a robotic arm perpendicular to an artificial stone. A single laser pulse was triggered at different working distances (0–2.0 mm in 0.2 mm increments) between the distal fiber tip and the stone. To achieve a measurable impact, pulse energy was set to 2 and 3 J, with either short or long pulse duration. Ablation volume was calculated with an optical microscope. Experiments were repeated five times for each setting. Results: Highest ablation volume was observed with a long pulse of 3 J at a working distance of 0.4 mm between the laser fiber and the stone surface (p value < 0.05). At 2 J, the highest ablation volume was noticed with a short pulse in contact mode. However, ablation volume of the latter was not significantly greater than with a long pulse of 2 J at a working distance of 0.4 mm (p value > 0.05). Compared to lithotripsy in contact mode, triggering a single long pulse at 0.4 mm increased ablation volume by 81% (p value = 0.016) at 2 J and by 89% (p value = 0.034) at 3 J. Conclusions: For Ho:YAG laser lithotripsy, ablation volume may be higher in non-contact mode using long pulses, rather than in direct contact to the stone. Findings of the current study support the need of further studies of lithotripsy in non-contact mode.

OBJECTIVES To investigate the diagnostic accuracy, inter-rater and intrarater agreement of grade predictions based on the visual appearance of papillary upper tract urothelial carcinoma (UTUC) during digital ureteroscopy. METHODS Nine urologists predicted the histopathologic grade of 64 papillary UTUC (low-grade vs highgrade) by assessing the visual appearance of the tumors in videos from digital ureteroscopy. The diagnostic accuracy was estimated by comparing the grade predictions with the histopathology from colocalized biopsies. Inter-rater agreement was assessed by pairwise inter-rater percentage agreement and Fleiss Kappa analysis. The videos were rated in a random order again 30 days after the first assessment to evaluate the intrarater percentage agreement. RESULTS Low-grade tumors were predicted correctly in 37%-85% of the cases with a median concordance of 59% for questionnaire 1 and 66% for questionnaire 2. High-grade tumors were predicted correctly in 26%-91% of the cases with a median concordance of 52% and 61% for each questionnaire. The median pairwise inter-rater percentage agreement was 66% for both questionnaires with a Fleiss Kappa of 0.29 and 0.38, respectively. The median intrarater percentage agreement was 81%. CONCLUSION The histopathologic grade of UTUC is essential to the risk-stratification for treatment selection. Predictions of the histopathologic grade based on the visual appearance of papillary UTUC with digital ureteroscopy are often incorrect in comparison with biopsy results and yield low inter-rater agreement. Urologists must be aware of these limitations in the assessment of the tumor grade during digital ureteroscopy to warrant good clinical practice. (C) 2019 Elsevier Inc.

INTRODUCTION: We evaluated a new digital single-use flexible ureteroscope, LithoVue™ with respect to deflection, image quality and maneuverability.METHODS: A prospective cohort study was conducted in eight tertiary reference centers in Europe in December 2015 and January 2016. All consecutive patients included underwent flexible ureteroscopy and were 18 years or older. Deflection and image quality pre- and post-use and maneuverability were rated with a Likert scale.RESULTS: A total of 40 procedures were performed (five per institution). The indication for FURS was treatment of renal stones in 92.5 % of the cases. Before LithoVue™ usage, the median measured upward and downward deflections were both 270°. Image quality was rated as "very good" in 65 % of cases and "good" in 30 %. Maneuverability was "very good" in 77.5 % and "good" in 17.5 %. At the final evaluation, median upward and downward deflections were both 270°. Image quality was still "very good" in 65 % of cases and "good" in 30 % with no significant difference compared with preoperative data (p = 1). Maneuverability was "very good" in 72.5 % and "good" in 17.5 %, with no significant difference compared with preoperative data (p = 0.92). Two LithoVue™ broke during surgery (5 %): one occurring in extreme deflection with acute infundibulopelvic angle and spontaneous loss of vision for the second one.CONCLUSION: The LithoVue™ displayed good image quality, active deflection and maneuverability. Further evaluation of surgical outcomes and cost analysis will help to present the best utility of this single-use FURS in current practice.

Purpose: To evaluate LithoVue, the new single-use digital flexible ureteroscope, in a human cadaveric model and compare it with a nondisposable fiber optic and digital flexible ureteroscopes. Materials and Methods: LithoVue, a conventional fiber optic, and digital flexible ureteroscopes were each tested in four renal units of recently deceased female cadavers by three surgeons. The following parameters were analyzed: accessibility to the kidney and navigation of the entire collecting system with and without ureteral access sheath (UAS), lower pole access measuring the deflection of the ureteroscope with the working channel empty, and with inside two different baskets and laser fibers. A subjective evaluation of maneuverability and visibility was assessed by each surgeon at the end of every procedure. Results: Kidney access into the Renal unit 1 was not possible without UAS for all ureteroscopes because of noncompliant ureter at the level of sacroiliac joint. The reusable digital ureteroscope was unable to reach one calix of the lower pole and one calix of the upper pole (Renal units 2 and 3) without UAS placement. Lower pole access with baskets and laser fibers was possible for each ureteroscope after UAS placement. No statistically significant differences were detected in angle deflection between ureteroscopes. The digital ureteroscope was preferred for visibility in all procedures: LithoVue for maneuverability in six procedures, fiber optic in five procedures, and the digital ureteroscope in one procedure. Conclusions: LithoVue seems to be comparable with conventional ureteroscopes in terms of visibility and manipulation into the collecting system in fresh human cadavers. Further studies in humans are needed to determine the clinical value of this new instrument.

The improvements in flexible ureteroscopes provide efficient access to the upper urinary tract and advancements in laser technology strengthens the endourologists' armamentarium. The endourologists must be aware of the advantages and the potential complications of these powerful technological equipments. Our aim is to demonstrate temperature evolution during laser use inside an artificial kidney model.We created a bench model using K-Box(®) immersed into a saline-filled heating tank, which was used to obtain the needed temperature inside the cavity to provide different real-time situations. An endotracheal thermometer was placed inside. We used Olympus URF-P6 ureteroscope and Rocamed Holmium:yttrium-aluminium-garnet laser with two different fibers; 200 and 272 μm, at five different settings. Irrigation at room (24.5°C) and body (36.5°C) temperatures was used. We measured temperatures at 15th, 30th, and 45th seconds and 1st, 2nd, and 5th minutes of laser use with and without irrigation. We stopped measurements when temperature reached the upper limit of the endotracheal thermometer.When irrigation was closed, with 272-μm laser fiber, we reached the temperature limit more rapidly with saline tank at 36.5°C than the tank at 24.5°C. When irrigation was closed, with both fibers and regardless of tank temperature and laser settings, the system surpassed the maximum temperature limit. With 272-μm laser fiber, the limit was reached as early as the 30th second. When the irrigation was open, we did not reach the maximum temperature limit regardless of tank temperature and laser setting. When two laser fibers were compared, the temperature increase was more pronounced with 272-μm fiber, but the difference was not statistically significant.Laser use during flexible ureteroscopy may cause increased intrarenal temperatures. Rapid increases should be kept in mind when irrigation is closed. The irrigation seems to limit the temperature increase when used with any laser setting.

Kidney stones are currently managed using laser lithotripsy and the most recent generation of laser generators have enabled the possibility of the dusting technique. Dusting avoids the use of a basket, as stone fragments are spontaneously evacuated; however, no consensus on the definition of dust currently exists.

The aim of the present paper was to review the literature on all available ureteral access sheaths (UASs) with their indications, limitations, risks, advantages and disadvantages in current modern endourological practice. Two authors searched Medline, Scopus, Embase and Web of Science databases to identify studies on UASs published in English. No time period restriction was applied. All original articles reporting outcomes or innovations were included. Additional articles identified through references lists were also included. Case reports, editorials, letters, review articles and meeting abstracts were excluded. A total of 754 abstracts were screened, 176 original articles were assessed for eligibility and 83 articles were included in the review. Based on a low level of evidence, UASs increase irrigation flow during flexible ureteroscopy and decrease intrapelvic pressure and probably infectious complications. Data were controversial and sparse on the impact of UASs on multiple reinsertions and withdrawals of a ureteroscope, stone-free rates, ureteroscope protection or damage, postoperative pain, risk of ureteral strictures, and also on its cost-effectiveness. Studies on the benefit of UASs in paediatrics and in patients with a coagulopathy were inconclusive. In the absence of good randomized data, the true impact of UASs on surgery outcome remains unclear. The present review may contribute to the evidence-based decision-making process at the individual patient level regarding whether or not a UAS should be used.

International audience; PURPOSE:Ejaculatory dysfunction is the most common side effect related to surgical treatment of benign prostatic obstruction (BPO). Nowadays, modified surgical techniques and non-ablative techniques have emerged with the aim of preserving antegrade ejaculation. Our objective was to conduce a systematic review of the literature regarding efficacy on ejaculatory preservation of modified endoscopic surgical techniques, and mini-invasive non-ablatives techniques for BPO management.METHODS:A systematic review of the literature was carried out on the PubMed database using the following MESH terms: "Prostatic Hyperplasia/surgery" and "Ejaculation", in combination with the following keywords: "ejaculation preservation", "photoselective vaporization of the prostate", "photoselective vapo-enucleation of the prostate", "holmium laser enucleation of the prostate", "thulium laser", "prostatic artery embolization", "urolift", "rezum", and "aquablation".RESULTS:The ejaculation preservation rate of modified-TURP ranged from 66 to 91%. The ejaculation preservation rate of modified-prostate photo-vaporization ranged from 87 to 96%. The only high level of evidence studies available compared prostatic urethral lift (PUL) and aquablation versus regular TURP in prospective randomized-controlled trials. The ejaculation preservation rate of either PUL or aquablation compared to regular TURP was 100 and 90 versus 34%, respectively.CONCLUSIONS:Non-ablative therapies and modified endoscopic surgical techniques seemed to be reasonable options for patients eager to preserve their ejaculatory functions.

The holmium YAG (Ho:YAG) laser penetration depth (PD) of 0.4 mm has been widely described. Nonetheless, in physics, this concept refers to the tissue thickness at which 90% of the energy has been absorbed and not to the incision depth (ID) that the laser can achieve in tissue. The aim of this study is to evaluate the ablation efficiency of Ho:YAG laser on soft tissue.With an automated robotic arm, systematic fissures were performed on flat veal kidney specimens. Broad setting spectrums from 2.5 to 80 W, short and long pulse, were tested with 272 and 365 μm laser fibers. Experiments were repeated three times. Two pathologists in a blinded manner measured the width, depth, and coagulation area with electronic microscopy.The overall mean ID was 2 mm (0.25-4.39) and the mean width was 1 mm (0.3-3.1). The mean coagulation thickness was 0.48 mm (0.25-1.73). The higher the frequency and energy, the deeper and wider was the incision p 0.001. No differences were observed regarding the fiber diameter. The pulse length did not affect the ID, although the mean width was greater with short pulse p = 0.04. The outer mean coagulation was increased by increasing energy but not by increasing frequency p 0.119.The overall mean ID was significantly higher than the theoretical 0.4 mm PD described for Ho:YAG laser. The energy, frequency, and pulse length had individual effects regarding ID, incision width, and coagulation. The ID should be specified in accordance with the laser's power output and should not be confused with the physics of PD concept.

International audience; During the last decades, the surgical management of kidney stones benefited of many technological advances and one of them is the development of flexible ureteroscopy (fURS). This tool, ancillary equipment such as graspers and baskets, and lithotripsy technique with Holmium:YAG laser underwent many improvements leading to a widening of its indications with diagnostic and therapeutic management of upper urinary tract pathologies such as urolithiasis and urothelial tumors. The objective of this review is to describe the surgical technique for fURS as well as tips and tricks for the treatment of renal stones.

WOS: 000457123100013 PubMed ID: 30680241 Introduction We assessed the clinical performance of a new digital single-use flexible ureteroscope (UscopePU3022). Material and methods A prospective cohort study was carried out across 11 centers (July-Oct. 2017). The UscopePU3022 was assessed regarding ease of insertion; deflection, image quality, maneuverability and overall performance using either a visual analog* or Likert scale. Results A total of 56 procedures were performed in 11 centers (16 surgeons) with the indication being renal stones in 83%. The median score for ease of scope insertion was 10 (3-10). Intraoperative maneuverability was rated as 'good' in 38% and 'very good' in 52%. Visual quality was rated as 'poor or bad' in 18%, 'fair' in 37% and 'good very good' in 43%. Two scopes failed intraoperatively (4%). Preoperative and postoperative median upward and downward deflection was 270 degrees. Compared to standard flexible ureteroscopy (f-URS) maneuverability was rated as 'equivalent' in 30% and 'better' in 60%; visual quality was 'worse' in 38% and 'equivalent or better' in 62%; limb fatigue scores were 'better' in 86%; and overall performance was 'worse' in 55% and 'equivalent or better' in 45%. Conclusions UscopeTM3022 performed well with regards to maneuverability, deflection and limb fatigue and appears to be at least non-inferior to standard f-URS with regards to these parameters. Poor image quality is a concern for UscopePU3022 with it receiving a low overall performance rating when compared to standard f-URS. Despite this it scored highly when investigators were asked if they would use it in their practice if it was cost-effective to do so.

INTRODUCTION AND OBJECTIVES:Silicone was one of the first materials to be used for DJ ureteral stents. Due to its softness, it is purported to be associated with less patient discomfort. However, t...

Many urological societies have provided evidence-based guidelines to help the urologist make therapeutic choices. However, the recommendations in these guidelines may be heterogeneous because they were developed using various methods. The objective of this study was to review key guidelines on the surgical management of urinary stones to provide practical guidance for clinical application.Guidelines on urolithiasis from all international urological societies were searched through the society websites. A search on PubMed® and Medline® restricted to publications in English was also performed for guidelines published between January 1, 2010 and July 1, 2017. Only the latest versions of guidelines containing an evaluation of the level of evidence and the grade of recommendation were included in the final analysis. All recommendations on surgical stone management and recommended techniques for each surgical modality were included. The AGREE II (Appraisal of Guidelines for Research and Evaluation II) instrument was used to assess the quality of the included guidelines.Three international guidelines were included in analysis, including those of AUA (American Urological Association)/ES (Endourological Society), EAU (European Association of Urology) and SIU (Société Internationale d'Urologie)/ICUD (International Consultation on Urological Diseases). We highlighted the heterogeneity in the level of evidence and the grade of recommendation which arose due to the different methods of evaluations that had been adopted. Despite this our review highlighted the considerable similarities among the guidelines. In certain specific situations for which no good evidence was available the recommendations could only be based on expert opinion.An option to provide clear guidance to the urologist might be to combine these international guidelines into one to reduce confusion about the surgical management of urolithiasis.

International audience; PurposeWe evaluated a new single-use digital flexible cystoscope with an integrated grasper designed for double-J stent removal, Isiris™, addressing success rate, image quality, deflection, maneuverability and grasper functionality.MethodsIn September 2015, a prospective cohort study was conducted in six tertiary European reference centers. All consecutive patients included underwent double-J stent removal and were 18 years or older. Success rate was defined by complete stent removal. Image quality, deflection, maneuverability and grasper functionality were rated with a Likert scale.ResultsA total of 83 procedures were performed. 82% of procedures were performed in the endoscopy room, while the others were in the operating room since a consecutive endourological intervention was planned. The median duration of stent implantation was 28 days [14; 60]. In five patients, stent removal was not possible. Four patients had an incrusted double-J stent, and in one patient, the stent migrated into the ureter. After unsuccessful attempts of stent removal with conventional flexible cystoscope and grasper, the five patients had to be scheduled for an ureterorenoscopy procedure to remove the stent. In the other 78 patients, all double-J stents were removed successfully. Image quality, deflection, maneuverability and grasper functionality were rated as “very good” in 72.3, 78.3, 72.3 and 73.5%, respectively.ConclusionThis multicenter clinical evaluation of Isiris™ displayed good image quality, active deflection, maneuverability and grasper functionality. Further evaluation of stent removal outcomes, cost analysis and microbiology will help to delineate the possible place of Isiris™ in the current practice.