230 research outputs found

    Endoscopic Findings in Loin Pain Hematuria Syndrome: Concentric Clot in Calyceal Fornices

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    The loin pain hematuria syndrome (LPHS) creates a considerable burden, both for patients afflicted with the disease and for those involved in medical management and diagnosis. To date, the diagnosis of LPHS remains one of exclusion, with some speculation regarding the extent of actual pathology. We report ureteroscopic findings in 2 cases of LPHS. These findings provide objective confirmation of underlying pathology in a difficult-to-manage disease process

    Prospective randomized comparison of a combined ultrasonic and pneumatic lithotrite with a standard ultrasonic lithotrite for percutaneous nephrolithotomy

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    PURPOSE: To compare the efficiency and cost effectiveness of a combined pneumatic and ultrasonic lithotrite (Lithoclast Ultra) and a standard ultrasonic lithotrite, (LUS-1) during percutaneous nephrolithotomy. MATERIALS AND METHODS: In a prospective randomized trial, 30 patients undergoing percutaneous nephrolithotomy (PCNL) were randomized to PCNL with either the combined pneumatic and ultrasonic lithotrite (PUL) or a standard ultrasonic lithotrite (SUL). Patient demographics, stone composition, location, pre- and post-operative stone burden, fragmentation rates, and device failures were compared. RESULTS: There were 13 patients in the PUL group and 17 patients in the SUL group. Stone burden and location were equal. Overall, 64% of the PUL group had hard stones (defined as stones that were either pure or a mixture of cystine [3], calcium oxalate monohydrate [CaOxMono; 2], and calcium phosphate [CaPO4; 2]), and four had soft stones (3 struvite and 1 uric acid [UA]). In the SUL group, there were eight hard stones (5 CaOxMono and 3 CaPO4), and six soft stones (4 calcium oxalate dihydrate [CaOxDi] and 2 UA) (P = 0.51). Stone composition data were unavailable for five patients. Fragmentation time for the PAL was 37 minutes versus 31.5 minutes for the SUL (P = 0.22). Stone retrieval and mean operative times were similar for both groups. There were a total of three (23.1%) device-related problems in the PUL group, and eight (47%) in the SUL group. There was one (7.7%) device malfunction in the PUL group due to probe fracture. There were two (11.7%) device failures in the SUL group; one failure required the device to be reset every 30 minutes, and the second was an electrical failure. Suction tubing obstruction occurred twice (15.3%) in the PUL group and 35.3% in the SU group (P = 0.35). The stone-free rates for the PUL and SUL were 46% and 66.7%, respectively (P = 0.26). CONCLUSION: Although the PUL was more costly, stone ablation and clearance rates were similar for both the combined pneumatic and ultrasonic device and the standard ultrasonic device. When stratified with respect to stone composition, the PUL was more efficient for harder stones, and the SUL was more efficient for softer stones

    Real-time Simulation of Dynamic Vehicle Models using a High-performance Reconfigurable Platform

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    A purely software-based approach for Real-Time Simulation (RTS) may have difficulties in meeting real-time constraints for complex physical model simulations. In this paper, we present a methodology for the design and im-plementationofRTS algorithms,basedontheuseof Field-ProgrammableGateArray(FPGA) technologytoimprove the response time of these models. Our methodology utilizes traditional hardware/software co-design approaches to generate a heterogeneous architecture for an FPGA-based simulator. The hardware design was optimized such that it efficiently utilizes the parallel nature of FPGAs and pipelines the independent operations. Further enhancement is obtained through the use of custom accelerators for common non-linear functions. Since the systems we examined had relatively low response time requirements, our approach greatly simplifies the software components by porting the computationally complexregionsto hardware.We illustratethe partitioningofa hardware-based simulator design across dual FPGAs, initiateRTS usinga system input froma Hardware-in-the-Loop (HIL) framework, and use these simulation results from our FPGA-based platform to perform response analysis. The total simulation time, which includes the time required to receive the system input over a socket (without HIL), software initialization, hardware computation, and transferof simulation results backovera socket, showsa speedup of 2× as compared to a simi-lar setup with no hardware acceleration. The correctness of the simulation output from the hardware has also been validated with the simulated results from the software-only design

    Single-use versus reusable flexible ureteroscopes: a comprehensive cost-analysis decision model

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    Purpose: The significant improvements in flexible ureterorenoscopes have made flexible ureteroscopy the main treatment modality to target upper urinary pathologies. The purpose of this study was to critically evaluate all literature concerning the cost-effectiveness of flexible ureteroscopy comparing single-use with reusable scopes. Methods: A systematic online literature review was performed in PubMed, Embase and Google Scholar databases. Two separate urologists (GSM and FCT) performed the online search and reviewed all papers considered suitable and relevant for this analysis. Because of the paucity of high quality publications, not only prospective assessments but also case control and case series studies were included in the final analysis. All factors potentially affecting surgical costs or clinical outcomes were considered in the analysis. Results: 741 studies with the previously elected terms were found. Of those, 18 were duplicated and 77 were not related to urology procedures and were excluded. Of the remaining 646 studies, 59 published between 2000 and 2018 were considered of relevance to the pre-defined queries and were selected for further analysis. Stone free and complication rates were similar between single-use and reusable scopes. In special, urinary tract infection rate following flexible ureteroscopy is not inferior if a single-use device is used instead of a reusable scope. Operative time was in average 20% shorter if a digital scope was used, single-use or not. There is a suggestion that the learning curve is shorter with single-use devices but this is not consistent in the literature. Surgeon expertise impacts the longevity of the flexible scope. Reusable digital scopes seem to last longer than optic ones, though scope longevity is very variable worldwide. New scopes usually last three to four times more than refurbished ones and single-use ureterorenoscopes have good resilience throughout long cases. Both sterilization method and cleaning process impact scope longevity, the best results being achieved with Cidex and a dedicated nurse to take care of the sterilization process. The main factors that negatively impact device longevity regarding patient and disease are lower pole pathologies, large stone burden and non-use of a ureteral access sheath. Conclusions: The cost-effectiveness of a flexible ureteroscopy program is dependent of several aspects that must be considered when deciding whether to choose between a single-use and a reusable ureterorenoscope. Disposable devices are already a reality and will progressively become the standard as manufacturing price falls significantly.Objetivo: As melhorias significativas nos ureterorrenoscópios flexíveis tornaram a ureteroscopia flexível a principal modalidade de tratamento para as patologias de trato urinário superior. O objetivo deste estudo foi avaliar criticamente toda a literatura sobre a custo-efetividade da ureteroscopia flexível comparando aparelhos de uso único com reutilizáveis. Métodos: Uma revisão sistemática da literatura online foi realizada nas bases de dados PubMed, Embase e Google Scholar. Dois urologistas distintos (GSM e FCT) realizaram a pesquisa online e revisaram todos os trabalhos considerados adequados e relevantes para esta análise. Devido à escassez de publicações de alta qualidade, não apenas as avaliações prospectivas, mas também os estudos de casos e séries de casos foram incluídos na análise final. Todos os fatores que potencialmente afetam os custos cirúrgicos ou os desfechos clínicos foram considerados na análise. Resultados: foram encontrados 741 estudos com os termos previamente eleitos. Destes, 18 eram duplicados e 77 não tinham relação com procedimentos de urologia e foram excluídos. Dos restantes 646 estudos, 59 publicados entre 2000 e 2018 foram considerados relevantes para as consultas pré-definidas e foram selecionados para análise posterior. As taxas de complicações e livres de cálculo foram semelhantes entre os escopos de uso único e reutilizáveis. Em especial, a taxa de infecção do trato urinário após ureteroscopia flexível não é inferior se um dispositivo de uso único for usado em vez de um reutilizável. O tempo cirúrgico foi em média 20% menor se um ureteroscópio digital foi usado, seja de uso único ou não. Há uma sugestão de que a curva de aprendizado é mais curta com dispositivos de uso único, mas isso não é consistente na literatura. A experiência do cirurgião afeta a longevidade do aparelho flexível. Os aparelhos digitais reutilizáveis parecem durar mais que os ópticos, embora a longevidade seja muito variável em todo o mundo. Os novos ureteroscópios costumam durar de três a quatro vezes mais do que os recondicionados e os ureterorrenoscópios de uso único apresentam boa resiliência em casos longos. Tanto o método de esterilização como o processo de limpeza impactam a longevidade do aparelho, sendo os melhores resultados alcançados com o Cidex e uma enfermeira dedicada para cuidar do processo de esterilização. Os principais fatores que impactam negativamente a longevidade do dispositivo em relação ao paciente e à doença são patologias do polo inferior, grande volume de cálculo e não uso de uma bainha de acesso ureteral. Conclusões: A relação custo-efetividade de um programa de ureteroscopia flexível é dependente de vários aspectos que devem ser considerados ao se decidir se deve escolher entre ureterorrenoscópio de uso único e reutilizável. Os dispositivos descartáveis já são uma realidade e se tornarão progressivamente o padrão a partir do momento que o preço de fabricação cair significativamente

    Standardization of microbiome studies for urolithiasis: an international consensus agreement

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    Numerous metagenome-wide association studies (MWAS) for urolithiasis have been published, leading to the discovery of potential interactions between the microbiome and urolithiasis. However, questions remain about the reproducibility, applicability and physiological relevance of these data owing to discrepancies in experimental technique and a lack of standardization in the field. One barrier to interpreting MWAS is that experimental biases can be introduced at every step of the experimental pipeline, including sample collection, preservation, storage, processing, sequencing, data analysis and validation. Thus, the introduction of standardized protocols that maintain the flexibility to achieve study-specific objectives is urgently required. To address this need, the first international consortium for microbiome in urinary stone disease - MICROCOSM - was created and consensus panel members were asked to participate in a consensus meeting to develop standardized protocols for microbiome studies if they had published an MWAS on urolithiasis. Study-specific protocols were revised until a consensus was reached. This consensus group generated standardized protocols, which are publicly available via a secure online server, for each step in the typical clinical microbiome-urolithiasis study pipeline. This standardization creates the benchmark for future studies to facilitate consistent interpretation of results and, collectively, to lead to effective interventions to prevent the onset of urolithiasis, and will also be useful for investigators interested in microbiome research in other urological diseases

    Long-term ureteroscopic management of upper tract urothelial carcinoma: 28-year single-centre experience

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    Background Long-term survival outcomes of patients who undergo endoscopic management of non-invasive upper tract urothelial carcinoma remain uncertain. The longest mean follow-up period in previous studies was 6.1 years. This study reports the long-term outcomes of patients with upper tract urothelial carcinoma who underwent ureteroscopic ablation at a single institution over a 28-year period. Methods We identified all patients who underwent ureteroscopic management of upper tract urothelial carcinoma as their primary treatment at our institution between January 1991 and April 2011. Survival outcomes, including overall survival, cancer-specific survival, upper-tract recurrence-free survival and renal unit survival, were estimated using Kaplan−Meier methodology. Results A total of 15 patients underwent endoscopic management, with a mean age at diagnosis of 66 years. All patients underwent ureteroscopy, and biopsy-confirmed pathology was obtained. Median (range; mean) follow-up was 11.7 (2.3–20.9, 11.9) years. Upper tract recurrence occurred in 87% (n = 13) of patients. Twenty percent (n = 3) of patients proceeded to nephroureterectomy. The estimated cancer-specific survival rate was 93% at 5, 10, 15 and 20 years. Estimated overall survival rates were 86, 80, 54 and 20% at 5, 10, 15 and 20 years. Only one patient experienced cancer-specific mortality. The estimated mean and median overall survival times were 14.5 and 16.6 years, respectively. The estimated mean cancer-specific survival time was not reached. Conclusions Although upper tract recurrence is common, endoscopic management of non-invasive upper tract urothelial carcinoma provides a 90% cancer-specific survival rate at 20 years in selected patients
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