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1.
Int Braz J Urol ; 45(4): 658-670, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31397987

RESUMO

PURPOSE: To critically review all literature concerning the cost-effectiveness of flexible ureteroscopy comparing single-use with reusable scopes. MATERIALS AND METHODS: A systematic online literature review was performed in PubMed, Embase and Google Scholar databases. All factors potentially affecting surgical costs or clinical outcomes were considered. Prospective assessments, case control and case series studies were included. RESULTS: 741 studies were found. Of those, 18 were duplicated and 77 were not related to urology procedures. Of the remaining 646 studies, 59 were considered of relevance and selected for further analysis. Stone free and complication rates were similar between single-use and reusable scopes. Operative time was in average 20% shorter with digital scopes, single-use or not. Reusable digital scopes seem to last longer than optic ones, though scope longevity is very variable worldwide. New scopes usually last four times more than refurbished ones and single-use ureterorenoscopes have good resilience throughout long cases. Longer scope longevity is achieved with Cidex and if a dedicated nurse takes care of the sterilization process. The main surgical factors that negatively impact device longevity are lower pole pathologies, large stone burden and non-use of a ureteral access sheath. We have built a comprehensive fi nancial costeffective decision model to fl exible ureteroscope acquisition. CONCLUSIONS: The cost-effectiveness of a fl exible ureteroscopy program is dependent of several aspects. We have developed a equation to allow a literature-based and adaptable decision model to every interested stakeholder. Disposable devices are already a reality and will progressively become the standard as manufacturing price falls.


Assuntos
Reutilização de Equipamento/economia , Ureteroscópios/economia , Ureteroscopia/economia , Análise Custo-Benefício , Desenho de Equipamento , Reutilização de Equipamento/estatística & dados numéricos , Humanos , Duração da Cirurgia , Ureteroscópios/normas , Ureteroscópios/estatística & dados numéricos , Ureteroscopia/instrumentação , Ureteroscopia/estatística & dados numéricos
2.
J Endourol ; 31(12): 1301-1306, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28978227

RESUMO

INTRODUCTION: Single-use ureteroscopes have been gaining popularity in recent years. We compare the optics, deflection, and irrigation flow of two novel single-use flexible ureteroscopes-the YC-FR-A and the NeoFlex-with contemporary reusable and single-use flexible ureteroscopes. METHODS: Five flexible ureteroscopes, YC-FR-A (YouCare Tech, China), NeoFlex (Neoscope, Inc., USA), LithoVue (Boston Scientific, USA), Flex-Xc (Karl Storz, Germany), and Cobra (Richard Wolf, Germany), were assessed in vitro for image resolution, distortion, field of view, depth of field, color representation, and grayscale imaging. Ureteroscope deflection and irrigation were also compared. RESULTS: The YC-FR-A showed a resolution of 5.04 lines/mm and 4.3% image distortion. NeoFlex showed a resolution of 17.9 lines/mm and 14.0% image distortion. No substantial difference was demonstrated regarding the other optic characteristics between the two. Across all tested ureteroscopes, single-use or reusable, the digital scopes performed best with regard to optics. The YC-FR-A had the greatest deflection at baseline, but lacks two-way deflection. The NeoFlex had comparable deflection at baseline to reusable devices. Both ureteroscopes had substantial loss of deflection with instruments in the working channel. The YC-FR-A had the greatest irrigation rate. The NeoFlex has comparable irrigation to contemporary ureteroscopes. CONCLUSIONS: The YouCare single-use fiberoptic flexible ureteroscope and NeoFlex single-use digital flexible ureteroscope perform comparably to current reusable ureteroscopes, possibly making each a viable alternative in the future. Newer YouCare single-use flexible ureteroscopes with a digital platform and two-way deflection may be more competitive, while the NeoFlex devices are undergoing rapid improvement as well. Further testing is necessary to validate the clinical performance and utility of these ureteroscopes, given the wide variety of single-use devices under development.


Assuntos
Equipamentos Descartáveis/normas , Tecnologia de Fibra Óptica/normas , Ureteroscópios/normas , Cor , Desenho de Equipamento , Humanos , Técnicas In Vitro , Ureteroscopia/instrumentação
3.
J Endourol ; 31(10): 1062-1066, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28817961

RESUMO

INTRODUCTION: To date, the ergonomics of flexible ureteroscopy (URS) have not been well described. We performed a study to assess the biomechanical stresses on urologists performing URS and to investigate the effect of ureteroscope type on these parameters. METHODS: Electromyography (EMG) was used to quantify the activation level of muscle groups involved in URS. Surface EMG electrodes (Delsys, Boston, MA) were placed on the right and left thenar, flexor carpi ulnaris (FCU), extensor carpi ulnaris (ECU), biceps, triceps, and deltoid. Three endoscopes were studied: single-use digital (Boston Scientific LithoVue), reusable digital (Karl Storz Flex-Xc), and reusable fiber-optic (Karl Storz Flex-X2). Each ureteroscope was used to perform a set sequence of navigation and procedural tasks in a training model. EMG data were processed and normalized to compare the maximum voluntary contractions between muscle groups. Cumulative muscular workload (CMW) and average muscular work per second (AWS) were used for comparative analysis. RESULTS: For navigational tasks, CMW and AWS were greatest for the ECU, followed in descending order by right and left thenar, FCU, biceps, deltoid, and triceps. For procedural tasks, CMW and AWS were greatest for the right thenar, followed in descending order by the left thenar, ECU, FCU, triceps, biceps, and deltoid. During navigational tasks, both LithoVue and Flex-Xc had lower CMWs for every muscle group than Flex-X2 (p < 0.05). LithoVue and Flex-Xc had similar AWS and both were lower than Flex-X2 for the right thenar, ECU, biceps, and deltoid activation (p < 0.05). During procedural tasks, both LithoVue and Flex-Xc had lower CMWs and AWS for right and left thenar, ECU, and biceps than Flex-X2 (p < 0.05). CONCLUSIONS: This study provides the first description of EMG-measured ergonomics of URS. Both the single-use and reusable digital ureteroscopes have similar profiles, and both have significantly better ergonomic metrics than the reusable fiber-optic ureteroscope.


Assuntos
Ergonomia/normas , Músculo Esquelético/fisiologia , Ureteroscópios/normas , Ureteroscopia/instrumentação , Braço/fisiologia , Fenômenos Biomecânicos , Eletromiografia , Tecnologia de Fibra Óptica , Humanos , Estresse Fisiológico/fisiologia
4.
J Endourol ; 31(10): 1090-1095, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28835120

RESUMO

OBJECTIVE: To assess the "body mass index" (BMI) (weight and length) of 12 flexible ureteroscopes (digital and fiber optic) along with the light cables and camera heads, to make the best use of our instruments. MATERIALS AND METHODS: Twelve different brand-new flexible ureteroscopes from four different manufacturers, along with eight camera heads and three light cables were evaluated. Each ureteroscope, camera head, and light cable was weighted; the total length of each ureteroscope, shaft, handle, flexible end-tip, and cable were all measured. RESULTS: According to our measurements (in grams [g]), the lightest ureteroscope was the LithoVue (277.5 g), while the heaviest was the URF-V2 (942.5 g). The lightest fiber optic endoscope was the Viper (309 g), while the heaviest was the Cobra (351.5 g). Taking into account the entirety of the endoscopes, the lightest ureteroscope was the Lithovue and the heaviest was the Wolf Cobra with the Wolf camera "3 CHIP HD KAMERA KOPF ENDOCAM LOGIC HD" (1474 g). The longest ureteroscope was the URF-P6 (101.6 cm) and the shortest was the LithoVue (95.5 cm); whereas the Viper and Cobra had the longest shaft (69 cm) and URF-V had the shortest shaft (67.2 cm). The URF-V2 had the longest flexible end-tip (7.6 cm), while the LithoVue had the shortest end-tip (5.7 cm) in both directions (up/down), while the URF-V had the shortest upward deflection (3.7 cm). CONCLUSIONS: Newer more versatile digital endoscopes were lighter than their traditional fiber optic counterparts in their entirety, with disposable endoscope having a clear advantage over other reusable ureteroscopes. Knowing the "BMI" of our flexible ureteroscopes is an important information that every endourologist should always take into consideration.


Assuntos
Desenho de Equipamento/normas , Ureteroscópios/normas , Ureteroscopia/instrumentação , Tecnologia de Fibra Óptica , Humanos
6.
J Endourol ; 29(8): 907-12, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25763759

RESUMO

BACKGROUND AND PURPOSE: Flexible ureteroscopy (URS) is widely implemented with a well-defined safety profile and low complication rates. Although rare, locked deflection of a flexible ureteroscope in the upper tract is a potentially serious complication with poorly understood etiology and is likely underreported. MATERIALS AND METHODS: We attempted to capture all cases of locked deflection during URS by performing an anonymous, online computer survey targeting members of the Endourological Society. The Manufacturer and User Facility Device Experience (MAUDE) database and published literature were queried to find additional cases. The indication for URS, method of ureteroscope removal, patient outcomes, incident reporting, and explanations provided by the manufacturer or third party repair service were obtained whenever possible. RESULTS: In total, 10 cases of locked deflection during flexible URS were identified. Survey responses were obtained from 250/2424 (10.3%) endourologists polled. Locked deflection was noted by 8/250 (3.2%). The reported literature and MAUDE database identified one case each. Successful removal was noted in four using retrograde manipulation techniques while a percutaneous approach was used in three patients. Open surgery was needed in two cases because of resultant ureteral avulsion, and in one case, an open ureterotomy was needed for ureteroscope extraction. According to our survey, locked deflection was reported to the patient in 4/8 cases, the hospital in 3/8 cases, and the Food and Drug Administration (FDA) 0/8 cases. The two cases reported outside of our survey both notified the FDA. The minority of respondents (2/8), including our group, felt improper surgical technique was responsible for resultant locked deflection. Specifically, removal of a completely deflected ureteroscope through a stenotic infundibulum should be avoided. Rather, in such a situation, the ureteroscope should be straightened under fluoroscopy before being withdrawn. CONCLUSIONS: Locked deflection of a flexible ureteroscope is rare and underreported. Some cases are attributed to surgical technique, and awareness is crucial for avoidance of this complication.


Assuntos
Falha de Equipamento/estatística & dados numéricos , Complicações Intraoperatórias/etiologia , Doenças Ureterais/diagnóstico , Ureteroscópios/normas , Ureteroscopia/efeitos adversos , Ureteroscopia/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos , Ureteroscopia/instrumentação , Ureteroscopia/estatística & dados numéricos
7.
Urology ; 84(1): 42-5, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24837456

RESUMO

OBJECTIVE: To evaluate the durability and cost of maintenance for outsourced, refurbished flexible ureteroscopes. MATERIALS AND METHODS: Ureteroscope usage and repair were prospectively recorded over a 365-day period at a large 836-bed public hospital. Cases were performed by 14 different urologists using either refurbished DUR-8 or DUR-8 Elite model ureteroscopes. Retrograde cases involving calculi, urothelial carcinoma, stricture, and diagnostic evaluations were included. Ureteroscope repairs were performed by a single outsourced repair vendor, not the original manufacturer. RESULTS: A total of 501 ureteroscopic cases involving 550 ureteroscope usages were performed over a 365-day period. Semirigid ureteroscopes were used for 281 (56.1%) cases and refurbished flexible ureteroscopes for 220 (43.9%). The reason for the ureteroscopy was calculi in 386 (77.0%) cases, urothelial carcinoma in 32 (6.4%), stricture in 36 (7.2%), and diagnostic in 47 (9.4%). No repairs were needed during this period for semirigid scopes. Ureteral access sheaths were used in 82 (37.7%) of the cases. A total of 32 instances of catastrophic breakage occurred. Each newly refurbished ureteroscope was used for an average of 6.9 times before incurring further damage requiring repair. CONCLUSION: Refurbished flexible ureteroscopes that have undergone comprehensive repair are extremely fragile in the setting of multiple surgeon users in a large public hospital that uses central processing for sterilization and storage. This poor durability results in significant maintenance, repair, and administrative inconvenience that should be considered along with the purchase price.


Assuntos
Ureteroscópios/estatística & dados numéricos , Custos e Análise de Custo , Desenho de Equipamento , Reutilização de Equipamento/economia , Reutilização de Equipamento/estatística & dados numéricos , Humanos , Manutenção/economia , Manutenção/estatística & dados numéricos , Estudos Prospectivos , Centros de Atenção Terciária , Fatores de Tempo , Ureteroscópios/economia , Ureteroscópios/normas , Procedimentos Cirúrgicos Urológicos/instrumentação , Urologia
8.
Int J Clin Pract ; 67(10): 1040-3, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24073976

RESUMO

INTRODUCTION: Flexible ureteroscopes are expensive and delicate instruments that are integral in the offering of a minimally invasive technique of diagnosis and treatment of urolithiasis. Published literature has identified the importance of early damage recognition in preventing frequent use of the scope that would lead to further damage and high repair and replacement costs. Our study was designed to examine the outcome of the pressure leak test on the condition of flexible ureteroscopes after every use and analysing the damage and costs of maintenance. PATIENTS AND METHODS: A prospective study was designed with two treatment groups. Group 1, 95 consecutive procedures (n = 95) of flexible ureterorenoscopy and laser fragmentation of renal calculi were performed with ACMI DUR 8, (a scope with no in-built leak test facility). This was compared against group 2, where 98 procedures of laser fragmentation of renal calculi (n = 98) were performed using Storz Flex X(2) Ureteroscopes (with a in-built leak test facility). All scopes in Group 2 were tested for pressure leak after every procedure and the outcome of the tests recorded. RESULTS: Both groups were comparable for grade of surgeon; stone location, size & number; access sheath usage and duration of lasering. In Group 1, there were seven scope damages resulting in repairs/replacement amounting to costs $46264.40 (7.1% damage). In Group 2, three scopes revealed a positive pressure leak test, implying damage with repair costs of $9952.80 (3.1% damage) (p < 0.05). Significant cost savings and reduction in downtime were made in Group 2. CONCLUSIONS: Pressure leak testing following flexible ureterorenoscopy helped to significantly control costs of maintenance and repair. Newer scopes should have a leak testing mechanism as it prevents further detrimental damage to the scope, build-up of repair costs are avoided and there is an increase in the longevity of these delicate instruments.


Assuntos
Ureteroscópios/normas , Desenho de Equipamento , Falha de Equipamento , Humanos , Pressão , Estudos Prospectivos
9.
Urology ; 81(4): 717-22, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23465156

RESUMO

OBJECTIVE: To present the damage to digital flexible ureteroscopes after 1 year of use in a tertiary stone center and our strategy to reduce the damage. MATERIALS AND METHODS: Data regarding all procedures performed with 3 new digital flexible ureteroscopes (Olympus URF-V) were collected. We examined the conditions under which the damage occurred and retrieved the manufacturer's repair reports. Two study groups were created. Group 1 included all the procedures performed before the introduction of a set of guidelines for safe use of the digital flexible ureteroscopes and a stepwise credentialing process for new surgeons. Group 2 included all the procedures performed thereafter. RESULTS: A total of 141 procedures were performed in 122 patients. Five events of damage occurred in the first study group and were related to working in maximum deflection. In the second group only 3 events occurred. The damage affected the angulation system, working channel, or body shaft. No damage occurred to the imaging system of any ureteroscope. The changes that were made after the first 5 months of use resulted in a significant prolongation of the number of uses before damage occurred for every ureteroscope (10.6 vs 21.6 uses before damage, P = .035). CONCLUSION: The optical system of the new digital ureteroscopes is very durable; however, the overall longevity depends on the correct handling of their use. By following the proposed guidelines for safe use and with monitored training of new users, these instruments can have a significantly longer lifespan.


Assuntos
Ureteroscópios/normas , Doenças Urológicas/cirurgia , Desenho de Equipamento , Falha de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Urol Clin North Am ; 40(1): 67-78, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23177636

RESUMO

Recent innovations in imaging equipment and novel instrumentation have helped ureteroscopy evolve from a diagnostic to a therapeutic tool. In this review, the authors highlight several of the most recent advances in ureteroscopy that have helped allow unprecedented access, visualization, and treatment of upper urinary tract pathologic conditions.


Assuntos
Ureteroscópios/normas , Ureteroscopia/tendências , Urolitíase/cirurgia , Procedimentos Cirúrgicos Urológicos/métodos , Desenho de Equipamento , Humanos
11.
World J Urol ; 31(4): 907-12, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22451168

RESUMO

OBJECTIVES: To evaluate the influence of different biopsy forcipes on the deflection, irrigant flow, and optical characteristics of flexible ureterorenoscopes and to assess tissue quality for histopathologic evaluation in an ex vivo setting. MATERIALS AND METHODS: The following five different biopsy forcipes were compared: Olympus (FB-56D-1; diameter 5Fr.), R. Wolf (829.601; 3Fr.), Karl Storz Medical (11275ZE; 3Fr.), Boston Scientific (Piranha; 505-160; 3 Fr.), and Cook BIGopsy (115CM; 2.4 Fr.). The devices were tested in 3 different ureterorenoscopes: Storz 11278 VU (Flex-X(2)), Storz 11278 V (Flex-X(C)), and Wolf Cobra (7326071/-6). Tissue samples were obtained from porcine upper urinary tracts. RESULTS: Baseline irrigation flow rates with empty channels were significantly higher in the Wolf Cobra than in Storz ureterorenoscopes (30.5 vs. 23 and 21 ml/min). The BIGopsy forceps allowed for higher flow rates in both Storz ureterorenoscopes (2.2 and 1.3, respectively) when compared to the other devices (0.5 and 0.6 ml/min). The Storz and Wolf biopsy forcipes resulted in the highest impairment of the deflection angle. In all 3 ureterorenoscopes, flow rates and deflection angle were least impaired by the BIGopsy. However, BIGopsy compromised the field of view (20 % reduction vs. 12 % by others). The largest sample of renal pelvis and ureter biopsies was obtained with BIGopsy and Storz(®) forcipes, respectively. The extent of artifacts and denuded urothelium were comparable in all samples. CONCLUSIONS: The various biopsy devices showed different impacts on irrigation flow, deflection, and field of view. The Cook BIGopsy best retains irrigation flow in single-channel flexible ureterorenoscopes and deflection. However, a smaller field of view may complicate handling and tissue acquisition.


Assuntos
Biópsia/instrumentação , Ureteroscópios/normas , Sistema Urinário/patologia , Animais , Biópsia/métodos , Desenho de Equipamento , Modelos Animais , Óptica e Fotônica/normas , Instrumentos Cirúrgicos/normas , Suínos , Irrigação Terapêutica/normas
12.
J Endourol ; 26(10): 1329-34, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22563938

RESUMO

BACKGROUND AND PURPOSE: Controversy exists in the literature regarding flexible ureterorenoscopy (F-URS) durability, with a variable expected number of uses from a new F-URS. In this study, a tertiary center experience with the use of two consecutive F-URS is reported and suggestions as to how to improve durability further are made. MATERIALS AND METHODS: All F-URS performed in the same tertiary care center between July 2009 and February 2011, with two new instruments Flex-X, were reviewed retrospectively. All renal pathology were included. Ureteral cases were excluded. A 9.5F semirigid ureteroscope was always used at the start for a ureteral optical predilation and to explore the upper urinary tract for possible lithotripsy/laser ablation/biopsy. The F-URS was introduced sequentially to explore the remaining calices. Data pertaining to the procedure were collected. The method of sterilization was complete immersion with Cidex®. RESULTS: The instruments were substituted after 113 and 102 procedures, respectively. The first F-URS was used for a total operative time of 79 hours and 10 minutes while the second one was used for 71 hours and 25 minutes (mean 75 hours and 15 min). Procedure duration was 15 to 175 minutes (mean 58 min). The flexible instruments were used for a mean of 42 minutes per procedure (range 13-153 min). The indications for F-URS were therapeutic in 75.4% and diagnostic in 22.8% of the cases. For lower pole calculi, the stone was relocated in 65.2% and managed with the nonflexed flexible instrument 90% of the time. The most common causes of damage of F-URS were: Deflection mechanism impairment, inner sheath damage, and fiberoptic bundle breaks. CONCLUSIONS: Increased durability of F-URS was from a variety of factors, a key element of which was the method of sterilization, while routine use of the semirigid instrument initially further contributed significantly to increase the number of F-URS procedures, saving overall costs.


Assuntos
Tecnologia de Fibra Óptica/tendências , Litotripsia/métodos , Ureteroscópios/normas , Ureteroscopia/normas , Cálculos Urinários/terapia , Desenho de Equipamento/tendências , Humanos , Litotripsia/normas , Estudos Retrospectivos , Ureteroscopia/métodos , Cálculos Urinários/diagnóstico
13.
Pediatr Surg Int ; 26(7): 733-8, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20521057

RESUMO

OBJECTIVES: To compare the results of two different ureteroscopes in pediatric ureteroscopy (URS) procedures. PATIENTS AND METHODS: Sixty-five consecutive URS procedures in pediatric population (39 males, 26 females) were retrospectively evaluated. The subjects were divided in two groups according to the type of ureteroscope used: Group 1 (n = 32, Wolf 8F) and group 2 (n = 33, ACMI 6.9F). All the procedures performed in both groups were statistically compared regarding patient age, gender, lateralization, complication rates, whether the procedure was diagnostic or therapeutic, and whether a guide-wire was used. Additionally, in cases with ureteral stones, stone clearance rate and the necessity of a stone extractor were also compared between the groups. All data were statistically analyzed using chi-square and t tests, where appropriate. A p value less than 0.05 was considered as significant. RESULTS: Mean age of the groups were comparable (9.44 +/- 4.3 and 8.67 +/- 3.9, p = 0.456). There was no statistically meaningful difference between the groups regarding patients' gender, lateralization rates, whether the procedure was diagnostic or therapeutic, the need for a guide-wire use, and complication rates (p > 0.05). In cases with ureteral stones, both groups exhibited statistically comparable results in stone clearance rates and the use of a stone extractor (p > 0.05). CONCLUSIONS: Data on this comparison demonstrated that both ureteroscopy devices in pediatric population can be used safely in URS procedures. Neither the diameter nor the rigidity is significantly affecting the outcomes and success rates

Assuntos
Cálculos Ureterais/cirurgia , Ureteroscópios/normas , Ureteroscopia/métodos , Adolescente , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Desenho de Equipamento , Segurança de Equipamentos , Feminino , Humanos , Masculino , Estudos Retrospectivos
14.
J Endourol ; 21(10): 1187-94, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17949323

RESUMO

BACKGROUND AND PURPOSE: Urologic resectoscope loops often are manipulated to reposition the angle. The effects of these maneuvers on the efficiency and functionality of the loop have never been tested. Our goal was to evaluate the changes in tensile strength, conductivity, and dispersion of cautery effect resulting from such manipulation. MATERIALS AND METHODS: Resectoscope loops manufactured by Karl Storz, Olympus, Boston Scientific, and ACMI were tested for tensile strength and unevenness of cautery effect before and after one manipulation from an angel of 15 degrees posterior to 15 degrees anterior deviation. RESULTS: Prior to manipulation, the loops demonstrated a tensile strength of approximately 40 lb to failure. After one manipulation, the tensile strength was reduced by 90.1% (P < 0.001), with 46.7% of the loops failing to meet minimum industry standards. Manipulation of the loops increased the resistance to current flow within the wire. Microscopic evaluation showed longitudinal fracture lines at the manipulated sites. CONCLUSION: Physician-manipulated resectoscope loop angles have a dramatic effect on the strength of the loop as well as the dispersion of energy. A bend of 30 degrees results in 46.7% of the loops failing to meet minimum tensile-strength standards and alters the effectiveness and dispersion of electrical current. Infrared photography confirms the defect to be generated at the point of manipulation, thereby reducing the anticipated capabilities at a constant setting of the loop energizer. Ultimately, the quality of surgical resection suffers from even one manipulation of a resectoscope loop.


Assuntos
Endoscópios/normas , Endoscopia/métodos , Histeroscopia/métodos , Ureteroscópios/normas , Endoscopia/normas , Humanos , Histeroscopia/normas , Doenças Urológicas/cirurgia
15.
BJU Int ; 100(1): 157-9, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17552963

RESUMO

OBJECTIVE: To compare the relative ease of manipulation around a calyceal model in the hands of experienced ureteroscopists of four flexible ureteroscopes (FUs), as new-generation FUs provide exaggerated active deflection to facilitate intrarenal manipulation. SUBJECTS AND METHODS: Four FUs of <7.5 F were tested: the FlexVision U-500 (SF) (Stryker Endoscopy, San Jose, CA, USA), the Dur-8 Elite (D8E) (ACMI, Southborough, MA, USA), the Viper (Richard Wolf Medical Instruments, Vernon Hills, IL, USA) and the URF-P3 (Olympus Surgical, Orangeburg, NY, USA). Eight experienced ureteroscopists, each with a minimum of 100 flexible ureteroscopies over the preceding 3 years, assessed the FUs. The Mediskills calyceal model represents a moderately hydronephrotic collecting system, with a renal pelvic width of 2 cm, infundibular widths of 1 cm and infundibular lengths of 2 cm. The middle calyx infundibular angle was 80 degrees and the lower calyx infundibular angle was 100 degrees . The model does not allow for significant passive secondary deflection. The surgeons manoeuvred systematically around a four-point course, from the pelvi-ureteric junction, to anterior lower calyx, to anterior middle calyx, to posterior lower calyx, to posterior middle calyx, touching a metal sensor with an fulguration electrode, to trigger an automated signal at each calyx. The order of FU used by each surgeon was randomized. Each surgeon performed the course twice with each FU, ending with the first FU they started with, to diminish the impact of "learning the course". RESULTS: There were significant differences in the mean (sd) total time for manipulation through the four-point course, for the Viper, SF, D8E and URF-P3, at 29 (11), 37 (23), 38 (20) and 50 (24) s, respectively (P = 0.034). The URF-P3 took longer to reach the posterior lower pole, at 18.1 (14.5) s than the Viper, SF and D8E, at 6.3 (2.8) (P = 0.004), 6.6 (3.3) (P = 0.008) and 7.7 (4.9) (P = 0.008), respectively. The Viper was quicker to reach the posterior middle pole, at 7.3 (4.0) s, than the URF-P3, SF and D8E, at 14.9 (13.1) (P = 0.036), 14.7 (14.3) (P = 0.056) and 12.7 (14.0) s (P = 0.115), respectively. Subjectively, six of eight endoscopists stated that the Viper was the better FU for ease of manipulation, while five of eight stated that the URF-P3 was the most difficult. Notably, all eight endoscopists had more clinical experience with the URF-P3 than with the other three FUs tested. CONCLUSIONS: In a model of a moderately hydronephrotic kidney with long infundibulum and limited ability to perform passive secondary deflection, FUs with exaggerated active deflection outmanoeuvred the URF-P3. The Viper was better for manipulation in the hands of experienced endoscopists.


Assuntos
Modelos Anatômicos , Ureteroscópios/normas , Ureteroscopia/métodos , Desenho de Equipamento , Humanos , Cálices Renais , Ureteroscopia/normas
17.
Urol Res ; 34(6): 389-92, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17082921

RESUMO

With a new generation of flexible ureterorenoscopes, a new area in stone management is emerging. Limitation of vision with these new instruments is often caused by insufficient irrigation flow, especially when using instruments like stone baskets, resulting from partial obstruction of the working and irrigation channel with these instruments. Empirically, new available smaller stone baskets seem to dramatically improve irrigation and therefore vision in clinical use. The goal of this study was to show objective differences in basket diameters and flow rates in an in vitro setting. Diameters and irrigation flows in flexible ureterorenoscopes depending on different sizes of stone baskets (Fr. 1.5-1.7-1.9-2.2-2.4-3.0) and different deflections were measured. The measured diameter of the baskets varied within the first 20 cm and the true measured size varied from the manufacturer's specified size to a different extent. The new generation of 1.5 and 1.7 Fr. baskets improved irrigation flow, even compared to the smallest commonly used baskets, up to 68%. Interestingly, deflection did not influence irrigation flow. This study confirmed the subjective impression of inadequate description of relevant basket diameters as well as that of a significant improvement of irrigation flow with the newest generation of stone baskets with smaller diameters.


Assuntos
Ureteroscópios/normas , Ureteroscopia/métodos , Urolitíase/terapia , Calibragem , Humanos , Irrigação Terapêutica
18.
Asian J Androl ; 7(4): 433-8, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16281093

RESUMO

AIM: To investigate the causes and costs of flexible ureteroscope damage, and to develop recommendations to limit damage. METHODS: The authors analysed repair figures and possible causes of damage to 35 instruments sent for repair to a leading UK supplier over a 1-year period, and calculated cost figures for maintenance of the instruments as opposed to repair and replacement costs. RESULTS: All damages were handling-induced and therefore did not fall under the manufacturer's warranty: 28 % were damaged by misfiring of the laser inside the instrument; 72 %, mainly crushing and stripping of the ureteroscope shaft tube, were likely to have occurred during out-of-surgery handling, washing and disinfection. Seventeen (4 %) instruments were not repaired and consequently taken out of service due to the extensive costs involved. Eighteen (51 %) ureteroscopes were repaired at an average cost of 10 833 USD. CONCLUSION: Damages to flexible ureteroscopes bear considerable costs. Most damages occur during handling between surgical procedures. Thorough adherence to handling procedures, and courses for theater staff and surgeons on handling flexible instruments may help to reduce these damages and prove a cost-saving investment. The authors provide a list of recommended procedural measures that may help to prevent such damages.


Assuntos
Falha de Equipamento/economia , Ureteroscópios/economia , Urologia/economia , Urologia/instrumentação , Equipamentos Médicos Duráveis/economia , Humanos , Lasers , Reino Unido , Ureteroscópios/normas
19.
Urology ; 66(5): 958-63, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16286103

RESUMO

OBJECTIVES: To perform an analysis of currently available manufacturer data regarding the character of ureteroscope damage. The high costs associated with the repair of flexible and semirigid ureteroscopes are well documented. Increased knowledge of the etiology of ureteroscope damage should aid urologists in prolonging the lives of these delicate instruments. METHODS: We requested data from the four major ureteroscope manufacturers (ACMI, Olympus America, Karl Storz, and Richard Wolf) on the types, speculated causes, costs, and frequency of ureteroscope damage. The results were tabulated in a blinded fashion and analyzed for trends. We then formulated guidelines that could be applied by practicing urologists. RESULTS: For both flexible and semirigid ureteroscopes, the frequency of repair increased with decreasing ureteroscope diameter and increasing instrument length. The cost of the repair was generally greater for flexible ureteroscopes (mean 4597 dollars) than for semirigid ureteroscopes (mean 2437 dollars). The major causes of flexible ureteroscope damage were working channel damage from laser burn or instrument passage and extreme scope deflection with an indwelling instrument. The primary reasons for semirigid ureteroscope repair included overtorquing and improper handling in the operating room and during sterile processing. CONCLUSIONS: Urologists can minimize the repair costs of flexible and semirigid ureteroscopes by taking precautions to eliminate laser fiber-induced damage and by avoiding overdeflection. Improved storage and handling of these instruments is also necessary. Although small-diameter ureteroscopes are favorable because of their increased mobility and ease of passage, physician and staff awareness of their increased fragility is vital in maximizing the longevity of these commonly used instruments.


Assuntos
Ureteroscópios , Desenho de Equipamento , Falha de Equipamento , Ureteroscópios/normas
20.
Int J Clin Pract ; 58(8): 756-7, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15372847

RESUMO

The lifespan of medical equipment must be maximised to ensure cost-effectiveness. Flexible ureterorenoscopes have become widely used in the diagnosis and treatment of urolithiasis. They are relatively expensive and current literature shows that they require frequent repair and replacement. We have analysed our data for the number of procedures and repairs required for each new instrument we have used. So far we have used four new flexible ureteroscopes, which have been used for a total of 375 procedures, an average of 94 procedures each. On average each required repair twice. We believe that a few simple precautions taken during use and storage help to maximise the lifespan of the flexible ureterorenoscope and our results would appear to support this.


Assuntos
Ureteroscópios/normas , Equipamentos Médicos Duráveis , Falha de Equipamento , Humanos , Fatores de Tempo
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