Search

Les avancées technologiques en endo-urologie font désormais de l'urétéroscopie souple (URSS) une technique de choix pour traiter les calculs urinaires mais aussi un casse-tête lorsqu'il s'agit de choisir son équipement. La mise en place d'un guide de sécurité au sein des cavités rénales (nitinol, 0,035″, « stiff ») par cystoscopie rigide est non obligatoire mais constitue un critère de sécurité. Il en est de même concernant les gaines d'accès urétéral, celles avec aspiration étant en cours d'évaluation. Si leur utilisation réduit la pression et la température au sein des cavités rénales facilitant la vision, leur insertion peut occasionner des lésions urétérales. Les systèmes d'irrigation utilisant la gravité avec pompe manuelle sont à privilégier pour minimiser le risque de barotraumatisme. Le choix de l'urétéroscope est complexe : diamètre, capacité de déflexion, position du canal opérateur et qualité de vision sont à considérer. Aussi, il est difficilement envisageable de n'utiliser qu'un modèle endoscope pour l'intégralité des URSS. Les lasers Holmium:Yttrium-Aluminium-Grenat (Ho:YAG) et Thulium Fibré (TFL) sont aujourd'hui recommandés pour le traitement des calculs urinaires en URSS, avec un avantage potentiel du TFL pour la pulvérisation fine. Les paniers sont nombreux et divers, leur taille et forme devant également être considérées avant acquisition. En fin d'intervention, un drainage urétéral n'est pas systématique, mais les sondes JJ en silicone ont montré des risques d'incrustation et de gêne fonctionnelle plus faibles que les sondes faites de polyuréthane. Flexible ureteroscopy is now widely used as the preferred option to surgically treat a urinary stone, due to several technological advancements. Thus, choosing the adequate equipment is challenging, but respects safety concepts. Indeed, placing the safety wire (nitinol, 0,035″, "stiff") under rigid cystoscopy is not mandatory but improve safety. Regarding ureteral access sheath (UAS), considerations are similar: UAS facilitates vision, pressure and temperature control but can also be responsible of ureteral injuries at insertion. Suction devices are now under evaluation and could not be discussed. To limit the barotrauma risk, irrigation devices with manual pumps should be used (40 cmH 2 0). Choosing a flexible ureteroscope (fURS) is challenging; a special attention has to be given to size, deflexion, working channel position and vision. Thus, using a single fURS is hardly imaginable. Both Holmium:Yttrium-Aluminium-Garnet (Ho:YAG) and Thulium Fiber (TFL) lasers are recommended to treat urinary stones during fURS, with a potential advantage of TFL on thin pulverization. A wide variety of baskets exists and size and shape have to be considered before acquisition. Finally, if ureteral stenting is not mandatory in uncomplicated cases, silicone stents present a lower risk of encrustation and stent-related symptoms compared to polyurethane ones. [ABSTRACT FROM AUTHOR]

Décrire la technologie du laser Thulium:Yttrium-Aluminium-Garnet pulsé (p-Tm:YAG) et ses résultats actuels pour lithotritie laser endocorporelle. Une revue de la littérature, interrogeant les bases Pubmed, Scopus, et Cochrane a été conduite en janvier 2024 utilisant les mots clés « laser », « pulsed Thulium:YAG », « stones » et « lithotripsy ». De par les faibles niveaux de preuve et nombre de publications, une revue narrative de la littérature a été réalisée. Le laser p-Tm:YAG est un laser à cavité avec un cristal YAG dopé aux ions thulium, pompé par des diodes laser. Avec une longueur d'onde du faisceau laser de 2013 nm, il présente un coefficient d'absorption dans l'eau intermédiaire entre le laser Ho:YAG et TFL. Le diamètre minimal utilisable des fibres laser est de 200 μm. Différentes modulations impulsionnelles sont proposées visant à minimiser la rétropulsion des calculs avec notamment une puissance crête (Peak Power) réglable (≥ 800 W). De multiples études comparatives in vitro suggèrent que la capacité du p-Tm:YAG à fragmenter les calculs serait similaire à celle de l'Ho:YAG ; au contraire, sa capacité à pulvériser (dusting) tous types de calculs serait similaire à celle du TFL, avec une faible rétropulsion. Une seule étude in vivo a confirmé la faisabilité de la lithotritie du p-Tm:YAG au cours d'une urétéroscopie souple avec des taux de sans fragment résiduel (< 3 mm) et zéro fragment résiduel de 95 % et 55 %, respectivement. Aucune étude comparative n'est disponible à ce jour. Le nouveau laser p-Tm:YAG pulsé pourrait représenter un compromis sûr et efficace entre le laser Ho:YAG et le TFL pour la lithotritie laser endocoporelle mais des études comparatives, notamment avec le TFL sont nécessaires pour définir sa place dans l'arsenal thérapeutique. To describe the pulsed-Thulium:Yttrium-Aluminum Garnet (p-Tm:YAG) laser technology and its current evidence for endoscopic laser lithotripsy. A literature review, querying PubMed, Scopus, and Cochrane databases, was conducted in January 2023 using keywords "laser", "pulsed Thulium:YAG", "stones" and "lithotripsy". Due to the limited level of evidence and the number of publications, a narrative literature review was undertaken. The p-Tm:YAG laser is a cavity laser with a thulium-doped YAG crystal, pumped by laser diodes. With a laser beam wavelength of 2013 nm, p-Tm:YAG presents an intermediate absorption coefficient in water between Ho:YAG and TFL lasers. The minimal usable diameter of laser fibers for this technology is 200 μm. Various pulse modulations are proposed to minimize stone retropulsion, including adjustable peak power (≥ 800 W). Multiple in vitro comparative studies suggest that p-Tm:YAG's ability to fragment stones is similar to that of Ho:YAG, while its ability to dust various types of stones is similar to TFL, with low retropulsion. A single in vivo study confirmed the feasibility of p-Tm:YAG lithotripsy during flexible ureteroscopy, with stone-free (< 3 mm) and zero-fragment rates of 95% and 55%, respectively. No comparative studies are available to date. The new pulsed p-Tm:YAG laser could represent a safe and effective compromise between Ho:YAG and TFL for endoscopic laser lithotripsy, but comparative studies, especially with TFL, are necessary to define its role in the therapeutic arsenal. [ABSTRACT FROM AUTHOR]

Les lasers sont aujourd'hui des outils incontournables en endourologie, aussi bien pour le traitement des calculs urinaires, que des tumeurs urothéliales (vésicales ou du haut appareil) ou de l'hypertrophie bénigne de prostate. Si pendant une trentaine d'années, le laser Holmium : Yttrium-Aluminium-Grenat (Ho:YAG) a été l'acteur prépondérant pour ces applications, les lasers thulium fibré (TFL) et Thulium : YAG (Tm:YAG) sont aujourd'hui des alternatives grandissantes. Les TFL et Ho:YAG sont désormais recommandés pour le traitement des calculs urinaires, un manque de données cliniques limite les recommandations concernant le Tm:YAG. Pour le traitement des lésions urothéliales (énucléation « en-bloc » vésicales ou vaporisation des lésions du haut appareil urinaire), Ho:YAG, TFL et Tm:YAG sont utilisables mais il n'est pas possible à ce jour de recommander une source laser en particulier. De la même manière, ces trois sources lasers semblent utilisables pour réaliser une énucléation endoscopique de prostate, bien que le recul soit plus important pour l'Ho:YAG. Les techniques chirurgicales et les courbes d'apprentissage vont dépendre de la source laser, responsables d'effets bien différents, qu'il faut donc prendre en considération avant d'acquérir un générateur laser. Nowadays, laser technology has become the gold standard for many endourological applications, encompassing the treatment of urinary calculi, urothelial tumors (bladder or upper tract), and benign prostatic hyperplasia. While the Holmium: Yttrium-Aluminum-Garnet (Ho:YAG) laser dominated these applications for about thirty years, thulium fiber laser (TFL) and Thulium: YAG (Tm:YAG) lasers are emerging as growing alternatives. TFL and Ho:YAG are now recommended for urinary calculi treatment, but a lack of clinical data limits recommendations for Tm:YAG. For urothelial lesion treatment ("en-bloc" enucleation of a bladder tumor or vaporization of upper urinary tract lesions), Ho:YAG, TFL, and Tm:YAG are usable, but it is not currently possible to recommend a specific laser source. Similarly, these three laser sources appear usable for endoscopic prostate enucleation, although there is more extensive experience with Ho:YAG. Surgical techniques and learning curves will depend on the laser source, which can produce different effects, requiring careful consideration before acquiring a laser generator. [ABSTRACT FROM AUTHOR]

This research aims to develop a multifunctional, water-based product for protecting and consolidating stone materials. A new synthesis strategy using water-diluted silane formulations, composed of TEOS and an alkyl monomeric silane (ETES) or a polymeric siloxane (PDMS), homogenized by ultrasonic irradiation was followed to produce hybrid networks and overcome the limitations of current hydrophobic consolidants. These formulations gave rise to low dry residues and hydrophobic surfaces on various stones, including on low and high porosity stone varieties. Despite some formulations originated cracked films, optimal concentrations of ETES and PDMS showed high protection levels against capillary water absorption with minimal impacts on the color and water vapor permeability of the stones. Besides demonstrating the initial efficacy of these new hybrid materials in modifying the inherent hydrophilic and water-absorbing properties of stones, this work further confirmed their ability to penetrate within the stone pores and their initial efficacy in consolidating porous stones. Thus, new water-based multifunctional hybrid materials capable of consolidating and protecting various types of stones from water-related damage have been developed. These novel materials align with both technical and environmental requirements. • New hybrid sonogels were prepared successfully with water-based formulations of silanes. • Different concentrations of ETES and PDMS turn various stones hydrophobic. • Optimal concentrations also reduce drastically the water absorption of very porous stones. • Formulations preserve the original water vapor permeability while offering protection. • A multifunctional role was confirmed, as they also improve the cohesion of porous stones. [ABSTRACT FROM AUTHOR]

Ureteral stents play an important role in draining urine, supporting the ureter, and preventing hydronephrosis and renal failure. Stones on the surface of ureteral stents can lead to local injury, urinary tract obstruction and tumor induction in patients. They are categorized as normal metabolic stones and infected stones according to whether bacterial infection occurs. To inhibit the formation of ureteral stones, monomethoxy poly(ethylene glycol)-poly(trimethyl carbonate) (mPEG-PTMC) is synthesized to improve the surface hydrophilicity of PTMC/PLCL biodegradable elastomers, and heparin/chitosan coatings are formed by layer-by-layer electrostatic self-assembly. The mPEG-PTMC effectively improves surface hydrophilicity without compromising the compatibility of the components. The contact angle is 62.58° when 10 wt% of mPEG-PTMC 37 is present. Extracorporeal immersion for 1, 5, and 10 weeks mimicks normal metabolic stones, SEM and ICP-OES show that the increase of hydrophilicity could reduce the adhesion of calcium oxalate stones. The HEP/CTS coating also significantly reduces the coverage of calcium oxalate on the surface of the sample, and the calcium concentration decreases by 68.5 %. Equipped with an extracorporeal dynamic urinary circulatory system to simulate the production of infected stones after bacterial infection, after seven days, mPEG-PTMC 37 halved the stone surface coverage. Compared to PTMC/PLCL elastomer, mPEG-PTMC 37 , mPEG-PTMC 28 and HTP/CTS coatings inhibit 38.72 %, 15.55 %, 39.60 % of Ca and 65.06 %, 57.47 %, 70.11 % of Mg, respectively. In addition, the heparin/chitosan coatings reduce the surface adhesion of Staphylococcus by 69.9 %. The cell experiments show the materials all have good biocompatibility. It makes a useful exploration for developing a new kind of ureteral stents. [Display omitted] • We synthesize mPEG-PTMC to steadily improve hydrophilicity of PTMC/PLCL elastomers. • mPEG-PTMC facilitates the reduction of normal metabolic stones and infected stones. • Heparin/chitosan coating is formed by layer-by-layer electrostatic self-assembly. • Heparin/chitosan coating reduces surface stone and Staphylococcus aureus adhesion. • The cell experiments show materials for ureteral stents have good biocompatibility. [ABSTRACT FROM AUTHOR]

Ureteroscopy (URS) can be proposed as first-line therapy for the management of pelvic stones from 10 to 20 mm and for lower ureteric stones in children. However, little is known about the success and the morbidity of URS in young children. Ureteroscopic treatment may present matters in young children because of the small size of the pediatric kidney and the small size of the collecting system. To assess safety and efficacy of URS for the treatment of urinary stones in children aged of 5 years or less. After the institutional ethical board approval was obtained, we conducted a retrospective, analytic, multicentric study that included all URS performed between January 2016 and April 2022 in children aged of 5 years or less. In this non-comparative case series, anonymized pooled data were collected from 7 tertiary care centers of pediatric patients. Endpoints were the one-session SFR at 3 months and per and postoperatives complications. Descriptive statistics were applied to describe the cohort. Eighty-three patients were included. For them, 96 procedures were performed at the median age of 3.5 years (IQR: 0.8–5) and median weight of 14 Kg (6.3–23). Median stone size was 13 mm (4–45). There were 65 (67 %) renal stones treated with flexible URS, most of which were in the renal pelvis (30 %) and in the lower calix (33 %). A ureteral access sheath was used in 91 % procedures. Preoperative ureteral stent was placed in 52 (54 %) of patients. None of patients had ureteral dilatation. The single-session SFR was 67.4 % (56.3 and 89.2 % for flexible URS and semi-rigid URS respectively) and children require 1.4 procedures to achieve complete stone clearance. The overall complication rate was 18.7 %, most of them were minor (Clavien I-II). Intraoperative perirenal extravasation (Clavien IIIb) due to forniceal rupture was documented in 6.2 % of cases, related to an increased intrapelvic pressure (IPP) performed in a closed pelvicalyceal system. Pediatric urologists should be aware of forniceal rupture based on the presence of extravasation of contrast during endourological procedures especially when they have difficulties to reach lower caliceal stone in small patient. URS in patients aged of 5 years or less, is a complex minimally invasive procedure with reasonable efficacy and low morbidity. Intrarenal stones treated by RIRS in young children carries the risk of additional procedures to complete stone clearance. Summary table No. of patients/procedures 83 patients/96 procedures Sex, n (%) Female 33 (39.7 %) Male 50 (60.2 %) Age (months) Mean ± SD 38.7 months ± 18 Median (IQR) 43.5 (8–60) Weight (kg) Mean ± SD 13.9 Kg ± 4.09 Median (IQR) 14 (6.3–23) Stone size (mm) Mean ± SD 16.1 mm ± 9.15 Median (IQR) 13 (4–45) No. procedures, n (%) Flexible URS 66 (68.7 %) Semi-rigid URS 30 (31.2 %) SFR after a single session, n (%) 67.4 % N. of procedures to achieve stone clearance, n (%) Mean ± SD 1.43 (±0.77) Median (IQR) 1 (1–5) Overall complication rate, n (%) 18 (18.7 %) Grade I 2 (2 %) Grade II 10 (10.4 %) Grade IIIb 6 (6.2 %) Follow-up (months) Mean ± SD 21 months ± 18.1 Median (IQR) 14 (2–72) [ABSTRACT FROM AUTHOR]

Pediatric urolithiasis has been increasing at rate of 4–10 % annually in the United States, most notably within adolescents and females. A significant number of patients will require surgical management of their stones. Primary ureteroscopy (URS) affords the opportunity to treat stones under a single anesthetic with lower re-treatment rates or anatomical and stone characteristic limitations compared to shockwave lithotripsy. Previous studies evaluating primary URS have been largely underpowered, are limited by stone location, and/or are not representative of the stone population in the United States. Primary study outcomes were the success of primary URS and patient characteristics associated with success. Secondary outcomes were the stone-free rate (SFR), 30-day emergency department (ED) visits, 30-day readmissions, and complications. We performed a retrospective cohort study of patients less than 18 years of age from 2011 to 2023 who underwent primary URS. Patients were excluded if a ureteral stent was placed prior to URS or diagnostic URS was performed. A successful primary URS was considered if access to the ureter was obtained and treatment of the stone(s) completed. In failed primary URS, a ureteral stent was placed for staged management. A total of 196 patients were included and primary URS was performed or attempted on 224 renal units. The median age was 15.8 (IQR 13.4–16.9) years and median follow up 8.4 (IQR 1.1–24.6) months. The success rate of primary URS was 79 %. No significant characteristics were appreciated for successful primary URS based on: overall age, <14 vs > 14 years of age, sex, body mass index, history of stones, history of endourologic procedures, preoperative alpha blockade, location of stone(s), multiple stones, type of URS, or acute treatment. In successful primary URS, the SFR was 88 % with stone size (p = 0.0001) the only predictor of having residual stones. The 30-day ED rate was 21.4 %, 30-day unplanned readmission rate was 12.5 %, and complication rate was 7.5 %. No long-term complications were appreciated. Our success of primary URS compares favorably to previously published literature. Our SFR rate, 30-day ED visits, 30-day unplanned readmission, and complication rates are similar to other studies. Limitations of the study are its retrospective design, selection bias, and intermediate follow-up. Primary URS can be completed safely in the majority of pediatric patients without any patient characteristics associated with success. We advocate for primary URS when possible due to the excellent SFR and potential of treating stones under a single anesthetic. [Display omitted] [ABSTRACT FROM AUTHOR]

Faire le point sur la prise en charge chirurgicale des calculs rénaux et/ou urétéraux bilatéraux. Rapporter les critères d'analyse intervenant dans le choix entre un traitement simultané en un temps et un traitement différé en deux temps. Discuter, préciser les arguments pour défendre l'une ou l'autre des deux stratégies. Analyse de la littérature (Pubmed, Medline, langue anglaise et française) portant sur les traitements chirurgicaux des calculs bilatéraux chez l'adulte. Les critères décisionnels reposent sur le nombre et la taille des calculs, la présence ou non d'anomalies sur la voie excrétrice urinaire supérieure, le terrain et les facteurs de comorbidité, l'environnement et l'expérience du chirurgien. Plusieurs séries (rétrospectives) rapportent les résultats et les complications d'un traitement simultané en un temps des calculs bilatéraux. Il existe peu d'études prospectives comparatives. La LEC bilatérale en un temps n'a plus d'indication, l'URS(S) et la NLPC en un temps donnent des bons résultats (SF), en respectant certaines conditions, avec un taux de complications qui reste significatif (fièvre, douleur, hémorragie) sans être significativement supérieur à un traitement différé en deux temps. Les deux techniques (URSS et NLPC) sont parfois combinées (centre expérimenté à deux équipes). Le traitement simultané en un temps apparaît, en termes de résultats et de morbidité, équivalent à un traitement différé en deux temps sous réserve d'une sélection rigoureuse des patients et de l'exécution de l'acte par des équipes expérimentées. Le traitement différé en deux temps des calculs rénaux et/ou urétéraux bilatéraux reste une approche prudente et sûre, encore d'actualité, à privilégier dans les situations de calculs de gros volumes, d'anatomie difficile de la VEUS, de comorbidité importante et en début d'expérience. Le traitement simultané en un temps apparaît équivalent pour certaines équipes, en termes de résultat et de morbidité, à un traitement différé en deux temps sous réserve d'une sélection des patients (calculs de faible à moyen volume, anatomie simple de la VEUS, sans comorbidité importante) et de sa réalisation dans un centre expérimenté. Au cours d'un traitement simultané en un temps, l'équivalent d'une « check-list » intégrant des critères cliniques et biologiques pourrait être recommandée avant de débuter le traitement de la deuxième unité rénale. Review the surgical management of bilateral renal and/or ureteral stones. Report the analysis criteria involved in the choice between a simultaneous or a sequential delayed treatment. Discuss and specify the arguments for defending the first or the second strategies. Analysis of the literature (Pubmed, Medline, English and French language) of surgical management of bilateral urinary stones in adults. The decision criteria are based on the number and size of the stones, the presence or absence of abnormalities of the upper urinary excretory tract, the comorbidity factors, the environment and the surgeon's experience. Several series (retrospective) report the results and complications of simultaneous treatment of bilateral stones during the same procedure. There are few comparative prospective studies. Simultaneous bilateral LEC has no indication. Simultaneous bilateral URS (S) or PCNL give good results (SF) under certain conditions with a significant rate of complications (fever, pain, bleeding) but not significantly superior to sequential delayed treatment. Both techniques (USSR and PCNL) are sometimes combined (experienced center with two teams). The outcome and the morbidity of the simultaneous treatments appears equivalent to the delayed treatment in two stages when performed by experienced surgeons on selected patients. The sequential delayed treatment of bilateral renal and/or ureteral stones remains a safe approach, which has to be favored in case of large volume stones, difficult anatomy of the upper urinary tract, significant comorbidity and at the beginning of a learning curve. In experienced centers on high selected patients (low to medium volume stones, simple anatomy, without significant comorbidity), the outcome and morbidity of the simultaneous treatment appears equivalent to a sequential delayed procedure. In this case, a checklist incorporating clinical and laboratory criteria may be recommended before starting treatment of the second renal unit. [ABSTRACT FROM AUTHOR]

Urolithiasis affects pediatric patients with severe acquired brain injury, in whom the role of several clinical variables and of the presence and composition of enteral nutrition has not been investigated. Retrospective chart review on 371 pediatric patients with severe acquired brain injury. We used an essential electronic database to check the association between stones and enteral feeding. We then picked at random paper clinical records until we collected 20 and 20 complete records for patients with/without stones, not matched. With that information, we tested the association of stones with: nutrition facts of enteral formulae (sodium, potassium, calcium, magnesium, phosphorus, proteins, vitamin C); bladder dysfunction, urinary infections, catheterisms, tracheostomy, gallstones, way of feeding; blood and urine exams before stones diagnosis; age, type and severity of injury; prior physical activity, relevant drugs. All patients with stones were fed enterally. At univariate statistics they were older, weighed more, received bigger volumes of hydration and nutrition; they had worse GCS, more UTIs and they alone received catheterisms; their nutrition mixes were richer in sodium. In multivariate logistic regression for stone development, UTIs (OR 11.4, 95% C.I. 1.6–83.4) and higher sodium nutrition content (OR 7.5, 95% C.I. 1.6–34.3) were risk factors; higher GCS (OR 0.66, 95% C.I. 0.43–0.99) and higher calcium nutrition content (OR 0.14, 95% C.I. 0.03–0.73) were protective factors. Besides known risk factors for urolithiasis, including UTIs, catheterisms, worse neurological states, also enteral nutrition was a risk factor, particularly with higher sodium and lower calcium contents. Future studies should test the effect of different sodium/calcium nutrition contents on lithogenesis. • Urinary stones often affect pediatric patients in rehabilitation from brain injury. • We associated stone formation with clinical and enteral nutrition factors. • Clinical risk factors were: enteral nutrition, catheterization, UTIs, worse GCS. • Nutritional risk factors were: higher sodium content, lower calcium content. [ABSTRACT FROM AUTHOR]

Abstract Manmade objects such as buildings, statues and other materials made from cement, brick and stone are subject to mechanical weathering. Windblown sand wears down sharp edges, causing loss of style, features and details. Heat and cold cause expansion cracks that permit water to enter, freeze and or expand, causing more damage. The aggressive environment of the North West coast of Egypt, including sea storms, streams sand to impingement the facades of the summer houses and causes severe staining, peeling and damage to the paints and finishes of the exterior. High maintenance cost of such houses may eventually discourage owners to maintain the style and the architectural integrity of the compounds and villages. Architectural designs utilizing appropriate building and finishing materials which resist the wear and erosion, caused by high speed sand and salt laden air carrying sand particles and sea water droplets, are of vital importance to reduce maintenance cost. This paper investigates the wear rates and erosion mechanism for different finishing materials such as plastic paints (Complico), artificial stone tiles, Pharos stones, Calcium Carbonate natural stones, and fired brick tiles. Tests showed considerable wear rates when the facades are oriented about 60 degrees from the local wind directions. The results indicate a superior performance for the fired brick tiles. Other materials may be used on facades with somewhat different orientations ranging between 45 and 70 degrees from the wind direction. [ABSTRACT FROM AUTHOR]

In this work, a noninvasive microwave-based system for monitoring water content of Cultural Heritage stone materials is presented. In particular, by placing a planar resonator in contact with the stone sample, an experimental relationship between resonant frequency and water content is obtained. To verify the suitability of the system, experimental tests are carried out on several types of stones: gentile; leccese; carparo; red brick; and red brick fabricated at high temperatures. The first three types of stones are typically found in Cultural Heritage structures, and they are particularly affected by deterioration and decay phenomena. As for the red bricks, they are found in buildings from the XVII Century. Measurements are performed for five levels of water content of the stone samples, and the empirical relationship between each considered water content level and the corresponding resonance frequency of the patch resonator are derived. To enhance the contact between the planar resonator and the rough surface of the stone, the patch is covered with a thin layer of soft silicon conductor. The obtained results demonstrate the robustness of the presented solution. [ABSTRACT FROM AUTHOR]

The efficiency of a hybrid patented consolidant (PAASi) and two commercially available hybrid coatings (a consolidant named AlSiX and a hydrophobic product named WS3) properly modified was assessed on a calcarenite substrate. Test routines based on standard recommendations were first applied to evaluate the performances of the consolidant and protective treatments, while the investigation of additional aspects such as penetration depth and interaction with the substrate was achieved by a multi-scale approach based on classic intrusion methods (mercury intrusion porosimetry) and Drilling Resistance Measurement System (DRMS), combined with non-invasive imaging techniques (X-ray computed micro-tomography and neutron radiography) and small angle neutron scattering (SANS). A distinct interaction of the products with the pore network of the stone was quantified in the range 0.007–200 µm. Their effects on capillary water absorption were also visualized with neutron imaging. The suitability of the products on the selected substrate was discussed, highlighting also how the applied routine can support conservation material studies. The results indicated that the Al-Si-based product led to unwanted effects. Alternative application methods and/or curing procedures have to be explored to overtake these undesirable changes. On the contrary, the polyamidoamine-based product seemed to be more suitable for calcarenite substrates conservation. The performances of the hydrophobic coating, when used in combination with consolidants, were strictly influenced by the pre-consolidation of the substrate. [ABSTRACT FROM AUTHOR]

To compare the efficacy, side effects, and cost-effectiveness between a single-use digital flexible ureteroscope and a reusable flexible ureteroscope in the treatment of paediatric renal stones. This analytic, case–control, monocentric study included all patients undergoing flexible ureterosopies for stone treatment. Between April 2016 and February 2019, a reusable (Flex-XC®, Karl Storz) flexible ureteroscope was used (control group), whereas a single-use (Uscope®, PUSEN Medical©) flexible ureteroscope was used in all procedures from March 2019 to April 2021. Clinical and procedural outcomes, operative times, complication rates, hospital stay, and costs per procedure were evaluated. Forty-three cases using a reusable flexible ureteroscope and thirty-nine using a single-use flexible ureteroscope were included in the study. Demographic patient characteristics, stone burden, location and composition, preoperative presence of a double-J stent, procedural outcomes, mean length of postoperative hospital stay, and complications (4.6% versus 5%, p = 0.81) were comparable between the two groups. Median operative duration for stone removal was 93 min (20–170) with reusable versus 81 min (55–107) with the single-use scope (p = 0.18). Scope failure occurred four times with the reusable scope and in no case with the single-use. The total cost per procedure associated with the use of single-use scopes (798 Euros) was lower than a reusable scope (1483.23 Euros). Single-use flexible ureteroscopes were created to bypass the problems incurred when reusable scopes were damaged and therefore not available for use in surgical procedures. Single-use flexible ureteroscopes are always immediately available and ready to be used, even in urgent cases, as they typically do not require maintenance or sterilization. Compared with their reusable counterparts, single-use flexible ureteroscopes have similar digital performance (270°), image quality and we found no difference in the success and complication rates. Cost analysis of a reusable flexible ureteroscope must consider the purchase price, maintenance and repair costs, and decontamination costs (including handling, detergent, bacterial culture, transportation, and storage costs). In contrast, only purchase price is included in cost analysis for single-use flexible ureteroscopes. Our study suggests that single-use flexible ureteroscopes may be associated with lower costs per procedure than their reusable counterparts. Single-use flexible ureteroscopes are an interesting alternative to their reusable counterparts, particularly in terms of material resource management. Cost analyses conducted using a low volume of cases representative of a paediatric urology division favour the use of single-use ureteroscopes. Summary table Summary table Reusable flexible ureteroscope (n=43) Single-use flexible ureteroscope (n=39) p Patients (n) 25 20 Stone free rate 88% 84% 0.39 Postoperative complication rate (%) 2 (4.6%) 2 (5%) 0.81 Operative duration (min) 93 (20-170) 81 (55-107) 0.18 Total cost per procedure (Euros) 1483.23 798 0.47 [ABSTRACT FROM AUTHOR]

The development of the construction industry has necessitated the creation of efficient high-quality materials, the use of which is cost efficient and can reduce energy costs and consumption of raw materials. The potential of the Portland cement should be utilized to the fullest, because concrete structures and concrete products are the foundation of modern Q. The promising direction of solving this problem in the production of the piece of wall materials is to develop technologies using high compression pressures. The article discusses the experimental studies of the substructure formation of building materials of high-filled dispersion, as well as the influence of technological factors on the dynamics of construction materials properties (for example, protecting and supporting structures) during long-term operational impacts. [ABSTRACT FROM AUTHOR]

We sampled different substrates (sand, gravel, leaf litter and stones) in the rainy and dry season to study the distribution and composition of benthic macroinvertebrates in tropical streams (northeastern Brazil). Benthic macroinvertebrates were distributed according to the substrates, with stones showing a higher richness and abundance of species and abundance of collector-gatherers and filter-collectors. The results of the PCoA showed a separation of stones from the other substrates and similarities between sand and gravel. [ABSTRACT FROM AUTHOR]

Citrus fruits are a very rich source of electrolytes and citric acid. They have been used traditionally for treating urinary ailments and renal stones. Citrus jambhiri is indigenously used as a diuretic. Present study aimed at establishing the antiurolithiatic potential of the juice of Citrus jambhiri fruits along with the elucidation of the mechanism involved in the urolithiasis disease defying activity. The antiurolithiatic activity was established by means of nucleation, growth and aggregation assay in the in vitro settings and by means of ethylene glycol mediated calcium oxalate urolithiasis in the male Wistar rats. Docking studies were performed in an attempt to determine the mechanism of the antiurolithiatic action. Present study revealed the role of C. jambhiri fruit juice in reducing nucleation, growth and aggregation of calcium oxalate crystals by possible reduction in the urinary supersaturation relative to calcium oxalate and raising the zeta potential of the calcium oxalate crystals. C. jambhiri fruit juice treatment in experimental rats produced significant amelioration of hypercalciuria, hyperoxaluria, hyperphosphaturia, hyperproteinuria, hyperuricosuria, hypocitraturia and hypomagnesiuria and ion activity product of calcium oxalate. It exhibited nephroprotection against calcium oxalate crystals induced renal tubular dilation and renal tissue deterioration. Docking studies further revealed high binding potential of the phytoconstituents of C. jambhiri viz. narirutin, neohesperidin, hesperidin, rutin and citric acid with glycolate oxidase and matrix metalloproteinase-9. C. jambhiri fruit juice possesses excellent antiurolithiatic activity. The study reveals antiurolithiatic mechanism that involves restoration of equilibrium between the promoters and inhibitors of stone formation; and inhibition of matrix metalloproteinases and glycolate oxidase. • Citrus jambhiri fruit juice exhibited anticrystallization activity in vitro and in vivo. • It restored balance in the promoters and inhibitors of stone formation. • It exhibited nephroprotection against calcium oxalate induced renal cellular insult. • Docking studies revealed inhibition of matric metalloproteinases and glycolate oxidase. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Protection of stony materials against biodeterioration by ecofriendly compounds. • Electroprecipitation of borates of different solubility to increase their applicability. • The treatment allows the precipitation of different boron compounds. • The treatment is effective in preventing the fungal colonization. • The crystallization habit and penetrability differ depending on the material to be treated. Biodeterioration is a serious threat to the preservation of cultural heritage. Currently, the chemical treatments used to combat it must fulfil a series of restrictions to ensure that they are not harmful to humans or the environment. Borates satisfy these conditions but due to its high degree of leaching its application is limited to indoor areas. The use of electroprecipitation may to increase the range of applicability by allowing to precipitate, along the entire section of the stony materials, of a mixture of boron salts with different solubility (zinc, magnesium, and sodium borates) to cover a wide range of moisture conditions. The results obtained show that electroprecipitation not only increases the penetration depth of boron compounds but also allows the formation of compounds of different solubility, which allows the treatment to last over time. Furthermore, the treatment increased the mechanical properties and reduced the porosity of the stones treated, all without causing significant aesthetic changes. [ABSTRACT FROM AUTHOR]

Background It is generally thought that gallbladder motility plays a more or less important role in the pathogenesis of gallstones. Some studies have shown that some abnormalities of its intrinsic innervations, but these studies were usually limited to one cell component. Aims We investigated the main cell components of gallbladder intrinsic innervation in patients with and without gallstones. Methods Archival gallbladder specimens from 39 patients, 27 with gallstones (age range 45–69 yrs) and 12 patients without gallstones (age range 39–71 yrs) were obtained. Full thickness sections were obtained from the gallbladder neck and immunohistochemistry was carried out for enteric neurons (neuron-specific enolase and calretinin), enteric glia (S100) and interstitial cells of Cajal (CD117 and CD34); tryptase staining was also done to distinguish the latter from mast cells. Results Apart from calretinin-positive neurons, patients with gallstones featured a significant decrease of neurons, enteric glial cells (EGC) and mast cells compared to those without gallstones; interstitial cells of Cajal were extremely few and only found in two patients, one for each group. Conclusions The intrinsic innervations of the gallbladder is abnormal in gallstone patients, and this may contribute to gallstone formation in these subjects. [ABSTRACT FROM AUTHOR]

Surface luminescence dating to Egyptian monuments of the age range 3000 B C to Hellenistic times has been applied for first time. Monuments include the Giza plateau (Sphinx Temple, Valley Temple, Mykerinus), the Qasr-el-Saqha, the Khasekemui tomb and the Seti I Temple with Osirion at Abydos. Equivalent doses were measured by the single and multiple aliquot additive and regeneration techniques, and dose rates by portable gamma ray probes, and with laboratory counting and dosimetry systems. The resulted ages have confirmed most conventional Dynastic dates, while in some cases, predating was obtained by some hundred of years. The dates are discussed in the light of current archaeological opinions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Seismic performance analysis of timber structures with stones and earth mortar infill. [•] Experimental campaign based on a multi-scale approach (joint, cell and entire shear wall). [•] Analysis of infill influence on stiffness, maximal load and equivalent viscous damping. [•] Seismic performance comparisons of similar constructions. [Copyright &y& Elsevier]

Abstract: This study aims to investigate the relationships between Schmidt hardness rebound number (RN) and ultrasonic pulse velocity (UPV) versus compressive strength (fc) of stones and bricks. Four types of rocks (marble, pink lime stone, white lime stone and basalt) and two types of burned bricks and lime-sand bricks were studied. Linear and non-linear models were proposed. High correlations were found between RN and UPV versus compressive strength. Validation of proposed models was assessed using other specimens for each material. Linear models for each material showed good correlations than non-linear models. General model between RN and compressive strength of tested stones and bricks showed a high correlation with regression coefficient R 2 value of 0.94. Estimation of compressive strength for the studied stones and bricks using their rebound number and ultrasonic pulse velocity in a combined method was generally more reliable than using rebound number or ultrasonic pulse velocity only. [Copyright &y& Elsevier]

Abstract: Background: Percutaneous nephrolithotomy (PCNL) is commonly used in the management of large upper renal tract stones. It is highly effective but carries a greater risk of significant morbidity than less invasive treatment options such as ureteroscopy or extracorporeal shock wave lithotripsy. Objective: Evaluate the current practice and outcomes of PCNL using a national prospective data registry. Design, setting, and participants: All surgeons undertaking PCNL in the United Kingdom were invited to submit data to an online registry. Measurements: Effectiveness was assessed by stone-free rates and safety according to complications including blood transfusion, fever, and sepsis rates. Results and limitations: Since January 2010, data on 987 patients who had 1028 PCNL procedures were collected. A total of 299 of 1012 procedures (30%) were for staghorn calculi, 299 (30%) for stones >2cm, 329 (33%) for stones 1–2cm, and 89 (9%) for stones <1cm. There were no significant differences in rates of failed access or complications according to whether a urologist or radiologist obtained renal access. There was a nonsignificant trend to a higher transfusion rate with balloon dilatation (7 of 222 [3.2%]) compared with serial dilatation (2 of 245 [0.8%]) of the renal tract (p =0.093). Totally tubeless procedures were not associated with higher complication rates but did lead to a significant reduction in median length of stay (3 d vs 1.5 d; p <0.0001). Intraoperatively, 78% of patients were believed to be stone free, which was confirmed in 68% with postoperative imaging. Blood transfusion was required in 24 of 968 patients (2.5%). The incidence of postoperative fever was 16% and of sepsis was 2.4%. Conclusions: The PCNL data registry is a unique resource providing vital information on current practice and critical outcome data. Using the registry, endourologists can audit their practice against national outcome data for this benchmark procedure. It will help surgeons counsel patients during consent for this complex endourologic procedure about the possible outcome in their hands. [Copyright &y& Elsevier]

Summary: Dew is important source of water in the Negev Desert, yet little is known about the chemical composition of dew and consequently about its possible role in supplying nutrients to the ecosystem. Dew was collected in Sede Boqer (SB) in the central Negev Highlands and in Nizzana (NIZ) in the western Negev Desert (P =95mm) during the fall of 1992 and analyzed for their main ion constituents. In addition, rain was also collected and analyzed. Dew composition was mainly of the Ca–SO4 type and showed high total dissolved ions (TDIs) ranging between 88 and 758mg/l, which decreased with an increase in dew precipitation. Contrarily, it increased with time since the previous dew event indicating that dissolution of dust particles may have a substantial contribution to the chemical composition of dew. When the ion concentration of dew per millimeter was compared to that of rain, all ions showed a substantial enrichment, of 1.5–7.7. High dew to rain ratios characterized the terrestrial ions and especially the major nutrients N (5.4–6.1), K (3.9–7.6), and P (3.5). When the annual contribution of dew nutrients was calculated for SB, total potential contribution was 2.5, 1.4 and 3.0 times that of rain for N, P, and K, respectively, albeit its low annual amount (∼38mm). The findings highlight the role of substrates subjected to enhanced condensation such as cobbles and stones, implying that they may serve as sink for nutrients, and may provide an additional explanation for the relatively high plant cover and high species composition in the Negev Highlands. It also implies that a possible decrease in dew precipitation due to global warming may also result in nutrient depletion and subsequently in a reduction in plant cover. [ABSTRACT FROM AUTHOR]

Summary: Objective: To evaluate the success of extracorporeal shock wave lithotripsy (ESWL) in the treatment of ureteric calculi and determine the factors which influence outcome. Patients and methods: A retrospective audit of patients with a single ureteric stone receiving ESWL was performed. Success was defined as complete stone clearance on post-treatment imaging. Patient demographics and stone characteristics were correlated to ESWL outcome. Results: 108 patients met the inclusion criteria for this study. The mean age of the patients was 52.5 years (range 24–89 years). 80% (86/108) of patients were male. Stone sizes varied from 4 to 19mm (mean 7.92mm). The overall ESWL success rate for ureteric stones was 79%. Treatment was more effective for smaller (p =0.003) and more proximally located stones (p =0.035). Stone size correlated with number of treatments required (p =0.005). A JJ stent in situ at the time of ESWL reduced the success rate (p =0.002). Conclusions: Stone size, site in the ureter, and the presence of a JJ stent were predictors of ESWL success. Our study from a District General Hospital in the UK demonstrates that ESWL may be used with high efficacy to treat ureteric stones. [ABSTRACT FROM AUTHOR]

Abstract: We report a retrospective audit of percutanoeus nephrolithotomy (PCNL) in the United Kingdom. Questionnaires were sent to centres performing PCNL throughout the UK and data was obtained on 681 procedures from 30 centres. A variety of practice is demonstrated. Complication rates were comparable to previously published data and stone free rates were lower. Our data would also appear to support the view that urologist access for PCNL is both safe and effective in the UK. [Copyright &y& Elsevier]

Background & Aims: We assessed the temporal relationship between abdominal pain and elevation in liver function tests (LFTs) in patients with acute symptomatic choledocholithiasis. Methods: Retrospective study of patients that presented within 12 hours of pain onset and were subsequently found to have choledocholithiasis. Results: We identified 40 patients with complete medical records. Levels of aspartate and alanine aminotransferases (AST and ALT) correlated with duration of pain (Pearson correlation, r = 0.633 and 0.622 respectively, P < .001 for both); the correlation was not as strong for γ-glutamyl transpeptidase (GGT) (r = 0.326, P = .046) and was not significant for alkaline phosphatase or bilirubin. This temporal association was stronger in patients that had undergone cholecystectomy versus those with intact gallbladders (for ALT, r = 0.603 vs r = 0.311, respectively). Eighteen patients, evaluated within 6 hours of pain, had normal or minimal alterations in LFTs; transabdominal ultrasound was abnormal in 6 (sensitivity 33.3%). All had repeat LFTs within 24 hours (mean 10.3 ± 6.9 hours later) and large increases in ALT and aspartate aminotransferase levels (mean 10.5- and 6.8-fold respectively; P < .01 for both), intermediate increases in glutamyl transpeptidase levels, (mean 4-fold, P < .05), and no changes in alkaline phosphatase levels. This significant increase in LFTs was the only indication of biliary pathology before endoscopy in 11/18 patients. Conclusions: Increasing duration of pain is associated with increasing LFTs (particularly transaminases) in patients with acute symptomatic choledocholithiasis. Patients with normal LFTs and ultrasound upon presentation should have repeat LFTs if biliary pain is suspected. The absence of significant biochemical abnormalities within the first 24 hours makes the diagnosis of symptomatic choledocholithiasis unlikely. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Studies evaluating the influence of age and gender on the distribution of the various types of pediatric urinary calculi are scarce. The aim of this study was to highlight the modification of epidemiological characteristics of this pathology according to patients'' sex and age. Patients and methods: A total of 205 calculi (from 122 boys and 83 girls) were analyzed by infrared spectroscopy between 1993 and 2007; 54.6% of the patients were under 5 years. Results: Calcium oxalate was the predominant constituent in 54.7% of stones, followed by calcium phosphate and purines (14.6% each). We found a predominance of calcium oxalate in females (59.1% vs 50.8%), and a male preponderance for struvite stones (12.3% vs 1.2%). There was an increasing prevalence of calcium oxalate stones with age in both genders (42.9% in infants vs 59.3% in older children). Purine stones were predominant in 20% of cases, but prevalence decreased with age (28.6% in infants vs 18.5% in older children). Conclusion: The increase in calcium oxalate stones in school-age children and the decrease in stones containing purines confirm a change in the etiology of urolithiasis according to age. [Copyright &y& Elsevier]

Abstract: Objective: The composition of urinary stones in children depends on socioeconomic conditions, geography and dietary habits. Pediatric urolithiasis remains endemic in developing countries. The aim of this study was to analyze stone composition in an Egyptian patient population. Patients and methods: We analyzed prospectively urinary stones from 100 consecutive children (73 males, 27 females), aged 14 months to 12 years. The stones were located in the upper urinary tract in 78%, lower urinary tract in 19% and both in 3%. Male patients had more lower urinary tract stones. On presentation 67% had flank pain and 37% had hematuria. Stones were treated by open surgery in 69% of patients, shockwave lithotripsy in 20% and endoscopic extraction in 13%. Results: The components of the upper urinary tract calculi were calcium oxalate (47%), ammonium acid urate (26%) and calcium carbonate (21%), whereas the main components of the lower urinary tract calculi were ammonium acid urate (27.2%), struvite (27.2%) and calcium carbonate (22.7%). Urinary tract infection was involved in the development of one third of the stones. Endemic stones were present in 17% of patients, and stones of metabolic origin in 15%. The etiology of stone formation remained unknown in one third of patients. Conclusion: The epidemiological profile of urinary stones in Egyptian children can now be considered intermediate between developing countries where dietary deficiencies are the main causes and developed countries where infectious and metabolic calculi are observed. [Copyright &y& Elsevier]

In patients with biliary obstruction, determining the level and the cause of the obstruction is essential because it can be a key factor for the next step in diagnostic or therapeutic intervention. Noninvasive cholangiography, such as computed tomography (CT) cholangiography or magnetic resonance (MR) cholangiography, allows the diagnosis of cause and level of biliary disease with minimal risk. Traditional magnetic resonance cholangiopancreatography (MRCP) is an established and effective noninvasive diagnostic modality particularly for extrahepatic biliary tract evaluation. Intrahepatic biliary duct evaluation and functional MR, including evaluating for leaks and gallbladder dyskinesia and outlet obstruction, are evolving diagnostic techniques that show promising results. CT cholangiography techniques are especially useful when MRI is not available or contraindicated or when the quality of MRCP images is suboptimal. CT cholangiography is particularly useful as an adjunct to surgery or postsurgical cases. The primary limitation of cholangiographic contrast-enhanced CT cholangiography (the most prevalent type of CT cholangiography) is its hindrance by poor liver function and/or high-grade biliary obstruction. In this setting MRCP is clearly superior. There are different types of CT cholangiography and MRCP. This article discusses the types of CT cholangiography and MRCP techniques and their clinical applications. [Copyright &y& Elsevier]

Summary: The kidney plays a critical role in regulating water homeostasis through specific proteins highly expressed in the kidney, called aquaporins, allowing water permeation at a high rate. This brief review focuses on some nephropathies associated with impaired urinary concentrating ability and in particular analyzes the role of aquaporin 2 in hypercalciuria, the most common metabolic abnormality in patients with nephrolithiasis. Specifically, this review discusses the relationship between hypercalciuria and impaired aquaporin 2−mediated water handling in both acquired and inherited disorders characterized by hypercalciuria, including those affecting the sensor of extracellular calcium concentration, the calcium-sensing receptor, which represents the principal target for extracellular calcium regulation of several tissues including parathyroid glands and kidney. In the kidney, the calcium-sensing receptor regulates renal calcium excretion and influences the transepithelial movement of water and other electrolytes. Understanding the molecular basis of alteration of kidney concentrating ability found in hypercalciuria will help for devising strategies for reducing the risk of nephrocalcinosis, nephrolithiasis, and renal insufficiency. [ABSTRACT FROM AUTHOR]

Abstract: Stones in the biliary tract are routinely identified using MRCP (magnetic resonance cholangiopancreatography). The noisy nature of the images, as well as varying intensity, size and location of the stones, defeat most automatic detection algorithms, making computer-aided diagnosis difficult. This paper proposes a multi-stage segment-based scheme for semi-automated detection of choledocholithiasis and cholelithiasis in the MRCP images, producing good performance in tests, differentiating them from “normal” MRCP images. With the high success rate of over 90%, refinement of the scheme could be applicable in the clinical environment as a tool in aiding diagnosis, with possible applications in telemedicine. [Copyright &y& Elsevier]

This report describes the unusual case of a patient affected by Crohn’s disease suffering from intestinal obstruction with recurrent occlusive symptoms not due to the intestinal disease, but to the presence of two calcified foreign bodies in the pelvis. The stones were surgically removed and analysed by reverse-phase liquid chromatography coupled to UV diode array detection and mass spectrometry (LC-UV-DAD-MS/MS), Chromatoprobe-MS/MS and by Fourier-transform-infrared spectroscopy (FT-IR) techniques. The combined mass spectrometric approaches allowed unequivocally to identify 5-aminosalicylic acid (5-ASA) in stone 1, and to demonstrate that its formation was due to an unmodified 5-ASA tablet, a formulation that must undergo complete dissolution in the small bowel. The second stone was constituted by a solid layer (no solvent-extractable material) identified by FT-IR as a polystyrene fragment. This indicates that accidental ingestion of a plastic material, followed by its calcification, was responsible for its formation. [Copyright &y& Elsevier]

Estimate of sorption of liquid materials inside porous stones is an important parameter in industrial material testing and cultural heritage conservation. In the latter case, a suitable polymer can be used for both consolidation and conservation, it being applied either in the final form or as its parent monomer, which is subsequently allowed to polymerize in situ by the classical method or by frontal polymerization. However, the sorption of such materials through the stone is often difficult because of their viscosity and/or stone porosity. For this reason, the amount of monomer (or polymer) is a parameter of great interest in order to determine the extent of protection reachable by the treatment. In this paper a new methodology based on X-ray tomography is presented. The methodology makes use of a contrast agent added to the monomer that does not interact with its propagation inside the stone and allows to increase the absorption coefficient and so to observe the monomer inside the sample, which is finally frontally polymerized. [Copyright &y& Elsevier]

Foreign bodies in the bladder and urethra have been already largely described either by their nature itself as well as by the circumstances of their introduction. If their presence often reveals dubious psychiatric behaviours, one must also evoke possible accidental introductions during transvesical surgery or migration from spaces adjacent to the bladder. The treatment of those foreign bodies can be sorted out through endoscopy or surgical approach. [Copyright &y& Elsevier]

This article presents a review of the interventional radiological procedures in the percutaneous management of the bile duct stones through T-tube or transhepatic tracts. Interventional stone removal techniques mainly include extraction through the T-tube tract with baskets or forceps and expulsion into the duodenum by means of baskets or balloon catheters with the dilatation of the sphincter of Oddi. Fragmentation or size reduction of the stone, dilatation of the strictures and cholangioscopic assistance can facilitate the procedures. [Copyright &y& Elsevier]

Infection stones (ammonium magnesium phosphate) and catheter encrustations have a common cause—urease producing microorganisms. With their rapid growth and frequent recurrences, infection stones are among the most troublesome of urinary system stones. For many patients with a long-term indwelling catheter, encrustations can be a severe problem. Urine composition is important, because, urine calcium enhances the crystallization process and urine citrate inhibits it. The role of non-urease producing microorganisms in stone forming processes is not well understood. Stones can now be successfully treated with a low morbidity index by percutaneous stone surgery or extracorporeal shock wave lithotripsy (ESWL) and recurrence of stone formation is then avoided by prolonged antibiotic treatment and oral citrate. Catheter encrustations and damage caused by ammonia released during urease activity can, however, be a serious problem in patients with indwelling catheters and our remedies are unsatisfactory. [Copyright &y& Elsevier]

National trend of the incidence of urolithiasis in Japan from 1965 to 1995. Background. A nationwide survey of urolithiasis in Japan was made in order to evaluate the chronological trend of upper urinary tract stones in the Japanese. It succeeded previous studies done in 1955, 1966, 1979, and 1990. Methods. All outpatient visits to urologists that resulted in a diagnosis of first-episode upper urinary tract stones in the years 1990 and 1995 were enumerated, irrespective of admission and treatment. The study enrolled all of the Japanese Board of Urology-approved hospitals, thereby covering nearly all urologists practicing in Japan. The annual incidence by sex and age was estimated and compared with the incidences in the previous nationwide surveys. Results. The age-adjusted annual incidence of first-episode upper urinary tract stones in 1995 was estimated as 68.9 per 100,000 (100.1 in men and 55.4 in women), a steady increase from 54.2 in 1965. The annual incidence has increased in all age groups, except in those of the first three decades. The peak age for both sexes has shifted in toward the older population's direction. Estimations of longitudinal changes between 1965 and 1995 showed that the annual incidence has more than doubled for the cohort of the 1965 census population (from 43.7 in 1965 to 110.9 in 1995) and that younger generations have had progressively higher annual incidences. Conclusions. The annual incidence of upper urinary tract stones in Japan has increased steadily over the past 30 years and will continue to do so in the near future, but it still is lower than in the United States. [ABSTRACT FROM AUTHOR]

Abstract: Background: Medical expulsion therapy has shown encouraging results in facilitating spontaneous clearance of ureteral stones after extracorporeal shock wave lithotripsy. However, no other study has yet determined the benefit of medical expulsion therapy for stones in different ureteral locations. Objective: The aim of the study was to evaluate tamsulosin as adjunctive therapy to extracorporeal shock wave lithotripsy (SWL) in terms of pain clearance of stones in the upper, middle, and lower ureter. Methods: Between June 2008 and July 2011, patients with a solitary ureteral stone that was ≥6 mm up to 15 mm and located in the upper, middle, or lower ureter undergoing SWL were evaluated. The patients were randomly allocated to a conservative treatment (group 1) and a tamsulosin treatment group (group 2). Administration of the drug was started immediately after SWL and was continued for a maximum of 28 days. Patients were evaluated for stone clearance, time to stone clearance, and number of SWL sessions. The pain intensity was evaluated by visual analog scale. Results: There were 64 patients in the control group and 59 in the tamsulosin group. The average stone sizes were 10.70 (3.20) mm and 11.40 (3.01) mm (P = 0.24). Group 1 and group 2 received 2507 (984) and 2759 (775) shock waves (P = 0.86), 1.53 (0.8) and 1.49 (0.75) sessions (P = 0.85), respectively. Mean visual analog scale scores and times to clearance were 3.81 (2.74) and 2.73 (2.28) (P = 0.00) and 12.59 (8.63) days and 8.34 (7.60) days (P = 0.00), respectively, for all stones in groups 1 and 2. Only the clearance time of upper ureteral stones between groups showed statistical significance (13.54 [8.32] days vs 7.10 [6.40] days; P = 0.00). Conclusions: Tamsulosin may help in the treatment of all ureteral stones after SWL, particularly stones in the upper ureter, with a shorter time to clearance and less need for analgesic drugs. [Copyright &y& Elsevier]

To identify risk factors associated with recurrent kidney stones in a paediatric cohort in a Belgian tertiary centre. Medical records of children with the first episode of urolithiasis between 1998 and 2016, followed at Ghent University Hospital initially and at least one-year follow-up were retrospectively reviewed. Patient characteristics, past medical history, presenting symptoms, the results of laboratory investigations and the applied management strategy were analysed. The significant variables from the univariate analysis were integrated into a backward conditional multivariate model. Ninety-seven children were included in the analysis, of which 33 (34%) presented with at least one episode of stone recurrence. In the univariate analysis, body mass index (BMI) > 85th percentile and asymptomatic stones at initial presentation were associated with 1.8 and 0.1 times lower risk of recurrent stones, respectively (p = 0.020, 95% confidence interval (CI):0.368–8.749 and p = 0.017, 95% CI:0.014–0.921). In contrast, immobilization resulted in a 10-times higher risk (p = 0.002, 95% CI:1.968–50.005) and the need for technical intervention was associated with a 3.2- times higher risk (p = 0.017, 95% CI:1.297–8.084) of developing recurrent stones. On multivariate analysis only BMI >85th percentile was associated with a 15 times lower risk of stone recurrence (p = 0.030, 95% CI:0.006–0.739). A possible explanation of reduced risk in patients with a BMI > 85th percentile may lie in a different metabolic profile. Immobilization as a risk factor can be explained by calcium metabolism, which is influenced by immobilization due to fractures, paralysis or motor disability because it causes resorption of the skeleton resulting in elevated blood calcium levels. This study showed that patients who presented without symptoms when the stones first occurred were less likely to have recurring kidney stones compared with patients with symptoms at initial presentation. When technical intervention was needed, we believe this is partly due to a larger stone burden, however we could not find an evidence-based explanation. The institutional protocol, which allowed to create a database with a limited number of patients, was lost to follow-up. Despite the retrospective setting some data were missing. There might also be a bias because the patients were followed-up at a tertiary centre. Possibly, our conclusions cannot be generalized toward the entire paediatric population. Of all the factors investigated in our cohort, BMI >85 th percentile and asymptomatic stones are associated with a lower risk of stone recurrence. Conversely, immobilized patients and those who require technical intervention at initial presentation may benefit from an intense follow-up after the first episode of urolithiasis. [ABSTRACT FROM AUTHOR]

Holmium:YAG (Ho:YAG) laser lithotripsy has broadened the indications for ureteroscopic stone managements in adults, but few evidence are currently available in the pediatric population. This article aimed to assess the outcome of Ho:YAG laser lithotripsy during retrograde ureteroscopic management of ureteral stones in different locations in children. The medical records of 149 patients (71 boys and 78 girls; median age 9.2 years) treated with Ho:YAG laser ureteroscopic lithotripsy in five international pediatric urology units over the last 5 years were retrospectively reviewed. Exclusion criteria included patients with renal calculi and/or with a history of ipsilateral stricture, renal failure, active urinary tract infection, or coagulation disorder. Stones were treated with dusting technique in all cases. The median stone size was 10.3 mm (range 5–17). Stones were located in the distal ureter in 77 cases (51.7%), in the middle ureter in 23 cases (15.4%), and in the proximal ureter in 49 cases (32.9%). The median operative time was 29.8 min (range 20–95). Intra-operative complications included five bleedings (3.3%) and seven stone retropulsions (4.7%). Overall stone-free rate was 97.3%. Overall postoperative complications rate was 4.0% and included two cases of stent migration (1.3%) (Clavien II) and four residual stone fragments (2.7%) that were successfully treated using the same technique (Clavien IIIb). On multivariate analysis, re-operation rate was significantly dependent on the proximal stone location and presence of residual fragments >2 mm (P = 0.001). This study is one of the largest pediatric series among those published until now. The study series reported a shorter operative time, a higher success rate, and a lower postoperative complications rate compared with previous series. A limitation of this study is that stone-free rates may be somewhat inaccurate using ultrasonography and plain X-ray compared with computed tomography (CT); the study's 97.3% success rate may be overestimated because no CT scan was done postoperatively to check the stone-free rate. Other limitations of this article include its retrospective nature, the multi-institutional participation, and the heterogeneous patient collective. The Ho:YAG laser ureteroscopic lithotripsy seems to be an excellent first-line treatment for children with ureteral stones, independently from primary location and size. However, patients with proximal ureteral stones and residual fragments >2 mm reported a higher risk to require a secondary procedure to become stone-free. Combination of techniques as well as appropriate endourologic tools are key points for the success of the procedure regardless of stones' size and location. [ABSTRACT FROM AUTHOR]

Summary Introduction The treatment of large renal stones (≥1 cm) in paediatric patients is challenging. The usual treatment options include percutaneous nephrolithotomy (PCNL) or shockwave lithotripsy (SWL). There is a rise in the use of ureteroscopy and laser stone fragmentation (URSL) for paediatric stones; however, outcomes of treatment for large renal stones in this age group are still largely unknown. Objective To investigate the outcome of URSL for large paediatric renal stones ≥1 cm treated at the present institution over the last 5 years. Methods A retrospective review was performed of outcomes from the prospectively maintained stone database. Only paediatric patients undergoing ureteroscopic (rigid or flexible ureteroscopy (URS)) procedures for stones ≥1 cm were included. Patient demographics, operative details, stone burden, hospital stay, complications and stone clearance were recorded and analysed. Results From April 2010 to June 2015, 18 paediatric patients with a mean age of 10.4 years (range 3.6–15) underwent 35 ureteroscopic procedures for large stones (≥1 cm). The stone location was in the kidney ( n = 14), ureter ( n = 1), and in both the kidney and ureter for the remaining three patients. Nine patients had multiple stones. There was a preceding history of PCNL in four patients, with one patient having URS combined with a PCNL. The mean follow-up was 2.7 years (range 0–5). A postoperative stent was inserted in 21 (60%) patients. The overall stone-free rate (SFR) was 89% for a mean of 1.8 procedures per patient (range 1–4) – see Summary Table below. There was an inability to access stone within a lower pole calyx in one patient, despite maximum deflection of the ureteroscope. No intra- or post-operative complications were noted, and mean hospital stay was 1.1 days (range 0–5). Discussion Published papers in adult literature have shown that ureteroscopy and laser fragmentation (URSL) is a viable alternative to PCNL. Newer equipment and improved techniques have resulted in SFRs being comparable with PCNL. A recent systematic review reported an SFR of 91% for large adult stones (>2 cm) for a mean 1.45 procedures per patient, and an overall complication rate of 8.6%. The present study has also demonstrated excellent outcomes in the use of ureteroscopy and laser fragmentation for the management of large paediatric stones with no complications. Conclusion The results show that paediatric URSL for large stones achieves a good SFR with minimal morbidity and is a good treatment option in established endourological units. Summary Table Summary Table Sex ratio Female 11: Male 7 Mean stone size 13.3 mm (range 10–25) Total stone burden 18.2 mm (range 10–65) Mean number of procedures 1.8 per patient Success rate 89% stone free [ABSTRACT FROM AUTHOR]

Abstract: Since the first silk suture material acting as a nidus for the development of subsequent common bile duct stones after cholecystectomy was described in 1897, several investigators have reported that suture materials may cause choledocholithiasis. Silk, chromic catgut, parasites, and other foreign bodies are known occasionally to form such niduses in the common bile duct. Surgical hemostatic clips have been used widely and generally are considered very safe. The first case of postcholecystectomy clip migration was reported in 1979. Its exact pathogenesis remains unknown; it generally is agreed that bile duct injuries, inappropriate clip placements, subclinical bile leak, and infections also have been postulated to contribute to clip migration. We report an unusual case in which the core of a biliary calculus in the common bile duct was found to contain a surgical clip. This case illustrates the potentially abrupt and late development of clip-related gallstones and highlights the need for long-term follow-up evaluation. [Copyright &y& Elsevier]