Olympus URF-P3 Research Articles

PD41-03 MULTI-INSTITUTION COMPARISON OF NINE FLEXIBLE URETEROSCOPES USING A VALIDATED FLEXIBLE URETEROSCOPE EVALUATION TOOL

You have accessJournal of UrologySurgical Technology & Simulation: Instrumentation & Technology II (PD41)1 Sep 2021PD41-03 MULTI-INSTITUTION COMPARISON OF NINE FLEXIBLE URETEROSCOPES USING A VALIDATED FLEXIBLE URETEROSCOPE EVALUATION TOOL Margaret Knoedler, Scott Quarrier, Shuang Li, Alex Uhr, Shreya Patel, John Bell, Kristina Penniston, Scott Hubosky, Rajat Jain, and Stephen Nakada Margaret KnoedlerMargaret Knoedler More articles by this author , Scott QuarrierScott Quarrier More articles by this author , Shuang LiShuang Li More articles by this author , Alex UhrAlex Uhr More articles by this author , Shreya PatelShreya Patel More articles by this author , John BellJohn Bell More articles by this author , Kristina PennistonKristina Penniston More articles by this author , Scott HuboskyScott Hubosky More articles by this author , Rajat JainRajat Jain More articles by this author , and Stephen NakadaStephen Nakada More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002051.03AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Clinical urologists need a standardized way to compare the quality of flexible ureteroscopes for clinical and research purposes. We validated a flexible ureteroscope evaluation tool (Bell 2017). Our objective was to apply the tool widely to test its consistency across multiple institutions and multiple ureteroscopes. METHODS: Ureteroscopes (n=9) were assessed using the ureteroscope evaluation tool by three academic institutions. Surgeons completed the evaluation tool at the end of cases for which a variety of flexible ureteroscopes were used [Stortz Flex Xc (Xc), Stortz Flex X2 (X2), Olympus URF-P5 (P5), Olympus URF-P6 (P6), Olympus URF-P7 (P7), WiScope, LithoVue, Dornier and Pusen]. The tool contains nine evaluation domains designed to provide a comprehensive assessment of the ureteroscope (Figure 1). The domains are: historic experience with the device, quality of image, strength of deflection, scope maneuverability, intuitiveness of controls, ease of irrigation, ease of ureteroscopic access, functionality of working channel and overall satisfaction. SPSS was used to conduct statistical analysis for internal consistency of the tool and MANOVA for comparing the scopes across domains. RESULTS: A total of 311 responses distributed across three institutions were completed for the nine ureteroscopes. Results demonstrated the tool’s internal consistency (Cronbach alpha coefficient=0.85). The ureteroscope with the highest overall satisfaction score was the P7 (4.81±0.26) and the lowest overall satisfaction score was the Pusen (1.43±0.79). Mean scores across domains are reported in Figure 2. CONCLUSIONS: Our evaluation tool can be used to evaluate new ureteroscopes as they come to market. This tool is applicable to a variety of ureteroscopes with consistent results across multiple institutions and over time. This is extremely important as urologists do not always have the ability to test each ureteroscope in hand. Source of Funding: None © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e681-e681 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Margaret Knoedler More articles by this author Scott Quarrier More articles by this author Shuang Li More articles by this author Alex Uhr More articles by this author Shreya Patel More articles by this author John Bell More articles by this author Kristina Penniston More articles by this author Scott Hubosky More articles by this author Rajat Jain More articles by this author Stephen Nakada More articles by this author Expand All Advertisement Loading ...

Establishment of orthotopic colorectal cancer model by colonoscopy with submucosal injection in living mice

Objective To set up a living mice colonoscopy platform to establish an orthotopic model of colorectal cancer in mice under direct vision, and to observe its biological behavior such as metastasis. Methods Eighteen-week-old male C57/BL mice were anesthetized, and the intestinal lumen of the mice was examined by a self-developed living mice colonoscopy and Olympus URF-P5 ureteroscopy, respectively. The imaging effects of the two methods were compared. Human colon cancer HT-29 cells were injected into the colonic mucosa of BALB/c-nu mice under direct vision. The colonoscopy was performed on the 3rd, 7th and 15th day after the injection to observe the tumor formation in the intestinal lumen. The mice were sacrificed when the body weight decreased significantly or cachexia appeared, and then the abdominal cavity was examined including the tumor formation and metastasis. Results The self-developed living mice colonoscopy platform can provide clear vision of enteric cavity, and no mice died in the colonoscopy examination. In vivo subcutaneous injection of HT-29 cells in mice was performed with a perforation rate of 15%, a mortality rate of 33.3%, a tumor formation rate of 62.5%, an abdominal metastasis rate of 60%, a liver metastasis rate of 25%, and an abdominal wall transfer rate of 25%. Conclusion The self-developed mice colonoscopy platform can be used for the study of colorectum in living mice. The imaging effect is no less than that of Olympus URF-P5 ureteroscopy. In addition, an orthotopic colorectal cancer model can be established by this platform combing with submucosal injection technology. Key words: Living mice colonoscopy; Submucosal injection; T stage; Tumor microenvironment; Orthotopic colorectal cancer model

PD42-06 ASSESSMENT OF NEW TECHNOLOGY IN URETEROSCOPY: A COMPARISON OF DIGITAL, FIBEROPTIC, AND DISPOSABLE DIGITAL URETEROSCOPES USING A NOVEL EVALUATION INSTRUMENT

You have accessJournal of UrologySurgical Technology & Simulation: Instrumentation & Technology II1 Apr 2017PD42-06 ASSESSMENT OF NEW TECHNOLOGY IN URETEROSCOPY: A COMPARISON OF DIGITAL, FIBEROPTIC, AND DISPOSABLE DIGITAL URETEROSCOPES USING A NOVEL EVALUATION INSTRUMENT John Roger Bell, Sara L Best, Kristina L Penniston, and Stephen Y Nakada John Roger BellJohn Roger Bell More articles by this author , Sara L BestSara L Best More articles by this author , Kristina L PennistonKristina L Penniston More articles by this author , and Stephen Y NakadaStephen Y Nakada More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2017.02.1898AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Currently there is no standardized evaluation instrument for evaluation and comparing flexible ureteroscopes for clinical or research purposes. Our goals were to test a novel evaluation instrument in order to assess the performance of flexible ureteroscopes including a new disposable digital flexible ureteroscope during clinical use. METHODS We designed a novel evaluation instrument comprised of 9 questions designed to provide a comprehensive assessment of a flexible ureteroscope. Response options were presented as an interval scale ranging from 0 to 5 with 5 being the best response possible. We tested the instrument at our institution by administering it after routine upper tract stone cases utilizing a flexible ureteroscope. Three flexible ureteroscope categories were evaluated including: fiberoptic (Olympus URF-P5/P6), reusable digital (Storz Flex Xc), and the LithoVue disposable digital (Boston Scientific). Any urologist or trainee who used the ureteroscope during the procedure was allowed to evaluate the ureteroscope. The instrument was completed independently of each other and opinions about the ureteroscope were not discussed during the procedure. Internal consistency was assessed with Cronbach's alpha and Pearson correlation coefficients were calculated to describe the linear relationship between items. Multivariate analyses were done to assess responses. RESULTS A total of 34 upper tract stone cases were performed resulting in 79 evaluations. The Storz digital scored the highest of the three ureteroscopes. The image quality was very good on the LithoVue outside the patient, but we did notice some distortion when performing laser lithotripsy that impaired vision. We found no difference in the ease of ureteral access between the ureteroscopes. The instrument demonstrated internal consistency (Cronbach's alpha = 0.85). The mean inter-item Pearson correlation coefficient was 0.46 (0.10 to 0.88), the highest of which related maneuverability to overall satisfaction (0.88). Respondents who had completed residency scored the ureteroscopes significantly lower in the areas of maneuverability, intuitiveness and overall satisfaction (P = 0.019, 0.003, and 0.046 respectively). CONCLUSIONS We report our results from a pilot study evaluating a novel flexible ureteroscope evaluation instrument during clinical use. All ureteroscopes performed well on our evaluation instrument during clinical use. Further validation is needed to assess the quality of this evaluation instrument. © 2017FiguresReferencesRelatedDetails Volume 197Issue 4SApril 2017Page: e814-e815 Advertisement Copyright & Permissions© 2017MetricsAuthor Information John Roger Bell More articles by this author Sara L Best More articles by this author Kristina L Penniston More articles by this author Stephen Y Nakada More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

İKİ CM’DEN KÜÇÜK PROKSİMAL ÜRETER TAŞLARININ FLEKSİBLE ÜRETERORENOSKOPİ İLE TEDAVİSİ

Ozet: Gunumuzde distal ureter taslarinin ilk basamak tedavisi rijid ureterenoskopidir. Ancak proksimal ureter taslarinin standart tedavisi halen tartismalidir. Son yillarda proksimal ureter taslarinda fleksibl ureterenoskopinin basari ile uygulanabilecegi literaturde yerini almaktadir. Bu calismada klinigimizde proksimal ureter taslarina uygulanan fleksibl ureterenoskopi sonuclari sunulmaktadir. Calismaya hastane kayitlari incelenen ve tum datalarina ulasilabilen 28 hasta dahil edildi. Tum hastalara preoperatif idrar kulturleri yapildi. Preoperatif diversiyonu olmayan hastalarin ureter orifislerine balon dilatasyon yapildi. Kilavuz tel uzerinden ilerletilen fleksibl ureterenoskop (Olympus URF-P5) esliginde sisteme girildi ve cerrahin tercihine gore farkli guc ayarlarinda ayni holmiyum lazer esliginde tas kirma islemi gerceklestirildi. Islem sonrasi hastalar direkt uriner sistem grafisi, ultrasonografi, intravenoz pyelografi gerektiginde bilgisayarli tomografi ile degerlendirildi. Hastalarin ortalama yasi 41 (22-84); 15’i (%53,6) erkek ve 13’u (%46,4) kadindi. 25 tas radyoopak, 1 tas semi-opak, 2 tas non-opak olmak uzere 16’si sag toplayici sisteme 12’si sol toplayici sisteme girisim yapildi. 13 (%53,6) hastaya islem oncesi swl uygulanmisti. Ortalama tas boyutu 105mm2 (49-400 mm2)’di. 11 (%39,3) hastada islem oncesi djs bulunmaktaydi. Ortalama ameliyat suresi 45 dakikaydi (35-80). Islem sirasinda 18 hastada (%64,3) anklave tas oldugu goruldu. Postoperatif 4 hastada (%14,3) diversiyon kullanilmazken yine 4 hastaya (%14,3) ureter kateteri konuldu ve birinci gun cekildi. 20 hastaya (%71,4) djs yerlestirildi. Islem sonrasi degerlendirmelerde tum hastalarda rezidu tas saptanmadi. Iki hastada (%7,1) erken donemde uriner enfeksiyon gozlenirken baska komplikasyona rastlanilmadi. Fleksibl ureterenoskopi, anklave taslar da dahil olmak uzere proksimal ureter taslarinda yuksek basari ve minimum komplikasyon orani ile uygulanabilir bir yontemdir. Anahtar Kelimeler: Ureterolitiazis, fleksible ureterenoskopi TREATMENT OF PROXIMAL URETER STONES LESS THAN TWO CENTIMETERS WITH FLEXIBLE URETERENOSCOPY Abstract: The first-line treatment of distal ureteral Stones is rigid ureterenoscopy. However, standard treatment of proximal ureteral stones is still controversial. In recent years, proximal ureteral stones can be managed with flexible ureterenoscopy (F-URS) successfully. This study presents results of F-URS due to the proximal ureteral stones in our clinic. 28 patients with accessible to all data were included in the study. Preoperative urine cultures were performed for all patients. Balloon dilatation of the ureteral orifice was done for patients without urinary diversion. Flexible ureterenoscope (Olympus URF- P5) was introduced over the wire and with different power settings of laser was applied according to the surgeon's preference. After the procedure, patients were evaluated x ray graphy, intravenous urography, ultrasonography and computed tomography when necessary. The average age of patients was 41 (22-84). 15 of patients (53.6%) were male and 13 of patients (46.4%) were female. 25 of stones were radiopaque, 1stone was semi-opaque, and 2 of stones were non-opaque while 16 of access was made on the patients’ right ureter and 12 of access was made on the patients’ left ureter. SWL was performed in 13 patients (%53,6) before the procedure. Mean stone size was 105mm2 (49-400 mm2). Eleven patients (%39,3) had double j stent before the procedure. Mean operative time was 45 minutes (35-80). During the operation, in 18 patients (64.3%) it was found to be completely obstructive stone. Postoperatively diversion was not use for 4 patients (14.3%), ureteral catheter placement was used for 4 patients (14.3%), which were pulled out on the first day. Double j stent was the choice of diversion on 20 patients (71.4%). There were no residual stones in all patients after the evaluation process. Urinary tract infection was the complication in two patients (7.1%) while other complications were not observed. Flexible ureterenoscopy is a reliable method with a high success rate and minimal complications in proximal ureteral stones. Key words: Ureter stone, Flexible ureterenoscopy

Cost Analysis of Flexible Ureteroscope Repairs: Evaluation of 655 Procedures in a Community-Based Practice.

The frequency of flexible ureteroscopy has increased with the introduction of improved instrumentation. Ureteroscopes allow increased endoscopic access to the ureter and kidney. However, maintenance and repair of scopes may increase the total procedure expense. In 3 years (8/2011-7/2014), 655 flexible ureteroscopies were performed at a single-specialty, urology, ambulatory surgery center. Procedures were performed by 26 board-certified urologists using four Olympus URF P5 flexible ureteroscopes. The instruments were handled by a single team and sterilized through the STERIS System E1. Repairs were performed by the manufacturer on an as needed basis. Patient records were reviewed to determine the preoperative diagnosis, operative time, location and size of the stone, and use of laser or ureteral sheath. The occurrence, nature of flexible ureteroscope damage, and cost of repairs were evaluated. Of the ureteroscopies performed, 78% was for the treatment of calculi (50.1% in the kidney). Mean stone size was 8.5 ± 0.2 mm, with larger stones (11 mm) located in the kidney. The flexible ureteroscope was advanced over a guidewire (88% of cases); a laser fiber was introduced in 70%, and a ureteral sheath was used in 13.4%. Mean procedure time was 40 minutes. The most common reasons for ureteroscope repair were cloudy lens (16 repairs) and broken optic fibers (9 repairs). There were 31 repairs during the study period (average 21 cases per repair). Flexible ureteroscopes were out of service for an average of 11 days per repair (range 3-20). The total cost of repairs was $233,150 or ∼$7521 per repair. The average repair cost per flexible ureteroscopy performed was $355. Expenses associated with instrument repair can significantly impact a procedure's net revenue, thus efforts should be made to minimize instrument breakage. The expense of repairing a flexible ureteroscope per procedure can be significant and needs to be considered when pricing this procedure.

Evaluation of Novel Ball-Tip Holmium Laser Fiber: Impact on Ureteroscope Performance and Fragmentation Efficiency

A novel ball tip (BT) holmium laser fiber has recently been developed, which features a modified rounded tip. The modification is purported to aid in insertion and minimize damage to the ureteroscope working channel. We evaluated this laser fiber with regard to stone comminution, tip degradation, insertional force into the ureteroscope, and impact on ureteroscope deflection. A 242 μm BT fiber and a standard flat tip (SF) fiber were compared. Four kilojoules was delivered to a BegoStone over a constant surface area using settings of 0.2/50, 0.6/6, 0.8/8, and 1 J/10 Hz. Fiber tip degradation was measured at 1 and 4 kJ. Ureteroscope deflection was measured with the Olympus URF-P5, URF-P6, and URF-V. Insertion force into a 270° angled ureteroscope sheath model was measured. A sample size of five fibers was used for each comminution energy setting. Comminution increased with pulse energy without significant difference between fibers. No significant differences in tip degradation were observed. Both fibers reduced deflection (10°-30°) in all ureteroscopes without significant differences between fibers. Four new fibers paired with new sheath models were used to test insertion force. The BT insertion forces were approximately one-third of the SF. One SF fiber caused significant damage to the sheath and could not be advanced completely. The BT fiber has comparable comminution, tip degradation, and ureteroscope deflection performance compared with the SF fiber while exhibiting reduced insertion force within an aggressively deflected working sheath. The new tip design is likely protective of the working channel without loss of performance.

PD42-09 ENDOSCOPIC VALVES AND IRRIGATION DEVICES: A COMPARATIVE ANALYSIS

You have accessJournal of UrologyStone Disease: New Technology1 Apr 2015PD42-09 ENDOSCOPIC VALVES AND IRRIGATION DEVICES: A COMPARATIVE ANALYSIS Sarah Tarplin, Michael Byrne, Manoj Monga, and Sri Sivalingam Sarah TarplinSarah Tarplin More articles by this author , Michael ByrneMichael Byrne More articles by this author , Manoj MongaManoj Monga More articles by this author , and Sri SivalingamSri Sivalingam More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2015.02.2594AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES A variety of irrigation systems are available for ureteroscopy (URS), from gravity-driven pressure bags to hand-operated pumps. Endoscopic valves maintain a water-tight seal during URS, while facilitating the passage of instruments. The relative ergonomics of different devices have not been established. Our aim is to compare the mechanical properties and usability of valves and hand-operated irrigation systems in an in-vitro setting that models clinical use. METHODS Four endoscopic valves were tested in vitro: UroSeal Adjustable Endoscopic Valve (US Urology), Adjustable Biopsy Port Seal (Gyrus ACMI), Blue Silicone Seal CS B612 (Gyrus ACMI), and REF ABP Biopsy Port Seal (ACMI). Leak point pressure (LPP) was tested with a Viper Ureteroscope (Richard Wolf Endoscopy) and the Thermedx Fluid Management System (TFMS, Thermedx). Insertion and extraction forces of instruments through the devices were measured. Insertion time was assessed for: [(a straight tip Sensor wire, 0.035”, Boston Scientific), a laser fiber (Flexiva 200, Boston Scientific), and an Ngage Nitinol Stone Extractor 1.7Fr (Cook Urological)] through a flexible ureteroscope (Olympus URF P5, Olympus). Flow rate, flow time, and user fatigue were tested for two irrigation systems: the Single Action Pumping System (SAP, Boston Scientific) and the Pathfinder Plus (PP, Utah Medical Products), using Uroflow (Delphis KT) and a Dynamometer for grip strength (Sammons Preston). RESULTS The US required the shortest time for both wire insertion and basket insertion (p=0.005, and p<0.001, respectively), while the BSS had the greatest time for laser fiber insertion (p<0.005). The REF ABP required the greatest force for withdrawal of all instruments through a closed seal, while the US required the least force for laser fiber withdrawal and insertion (p<0.001). The US was leak-free at pressures up to 200 mm Hg, while all other devices had a LPP ranging from 30 to 200 mm Hg. The SAP's average and peak flow were significantly higher than that of the PP (3.5 vs. 2.1 mL/s, p<0.002, 13.1 vs. 4.43 mL/s, p<0.01, respectively). Mean grip strength decreased significantly after operation of the SAP for ten minutes, while no loss of grip strength was observed after use of the PP. CONCLUSIONS The US has the benefit of facile manipulation of wires and baskets while maintaining a water tight seal. The BSS valve is cost-effective but limited by leakage and resistance during instrument passage. The PP has less operator fatigue, but the SAP may allow for greater on-demand pressures. Further studies are required to examine the effect of irrigation systems on stone migration. © 2015 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 193Issue 4SApril 2015Page: e889 Peer Review Report Advertisement Copyright & Permissions© 2015 by American Urological Association Education and Research, Inc.MetricsAuthor Information Sarah Tarplin More articles by this author Michael Byrne More articles by this author Manoj Monga More articles by this author Sri Sivalingam More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

MP28-06 COST ANALYSIS OF FLEXIBILE URETEROSOPE REPAIRS: EVALUATION OF 655 PROCEDURES IN A COMMUNITY-BASED PRACTICE EXPERIENCE

You have accessJournal of UrologyStone Disease: Surgical Therapy II1 Apr 2015MP28-06 COST ANALYSIS OF FLEXIBILE URETEROSOPE REPAIRS: EVALUATION OF 655 PROCEDURES IN A COMMUNITY-BASED PRACTICE EXPERIENCE Eugene Kramolowsky, Zachary McDowell, Blake Moore, David Rapp, and Nada Wood Eugene KramolowskyEugene Kramolowsky More articles by this author , Zachary McDowellZachary McDowell More articles by this author , Blake MooreBlake Moore More articles by this author , David RappDavid Rapp More articles by this author , and Nada WoodNada Wood More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2015.02.1229AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES The frequency of flexible ureteroscopy has increased with the introduction of improved instrumentation. These ureteroscopes allow increased endoscopic access to the ureter and kidney. However, the repairs required to maintain the scopes may increase the total expense related to the procedure. METHODS Over a three year period (8/2011 - 7/2014), 655 flexible ureteroscopies were performed at a single specialty urology ambulatory surgery center. The procedures were performed by 26 board certified urologists (15 doing greater than 10 cases) using four Olympus URF P5 flexible ureteroscopes. The instruments were handled by a single team and sterilized via the Steris System E1. Repairs were performed by the manufacturer on an as needed basis. Patient records were reviewed to determine the pre-op diagnosis, operative (OR) time, location and size of the stone, use of laser and use of ureteral sheath. The occurrence, nature of flexible ureteroscope damage, and cost of repairs were evaluated. RESULTS Of the 655 flexible ureteroscopies performed, 81% were for the treatment of calculi with 47% of these in the kidney. The mean stone size was 8.3 mm, with the larger stones (11 mm) located in the kidney. In the majority of cases (88%), the flexible ureteroscope was advanced over a guidewire. A laser fiber was introduced in 86% of the cases. A ureteral sheath was used in 12% of the cases. The mean procedure time was 39 minutes. The most common reasons for ureteroscope repair were cloudy lens (16) and broken optic fibers (9). There were 31 repairs during the study period (average 21 cases per repair). The flexible ureteroscopes were out of service for an average of 11 days per repair (range 3 - 20). The total cost of repairs was $233,150 or approximately $7,521 per repair. The average repair cost per flexible ureteroscopy performed was $355. CONCLUSIONS In an era of OR cost containment, the expenses associated with the repair of instruments can significantly impact the reimbursement of a procedure, thus efforts should be made to minimize instrument breakage. The expense of repairing a flexible ureteroscope per procedure can be significant and needs to be considered when pricing this procedure. © 2015 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 193Issue 4SApril 2015Page: e313 Advertisement Copyright & Permissions© 2015 by American Urological Association Education and Research, Inc.MetricsAuthor Information Eugene Kramolowsky More articles by this author Zachary McDowell More articles by this author Blake Moore More articles by this author David Rapp More articles by this author Nada Wood More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Endoscopic Valves and Irrigation Devices for Flexible Ureteroscopy: Is There a Difference?

A variety of ureteroscopic irrigation systems are available, ranging from gravity-driven pressure bags to hand-operated pumps. Endoscopic valves maintain a watertight seal during ureteroscopy (URS) while facilitating passage of instruments. The clinical utility and ergonomics of such devices have not been established. We systematically compare the mechanical properties and usability of select valve devices and hand-operated irrigation systems in an in vitro setting. In vitro testing of four different endoscopic valves: UroSeal adjustable endoscopic valve (US Urology), adjustable biopsy port seal (Gyrus ACMI), Blue Silicone Seal ACMI CS B612 (Gyrus ACMI), and REF ABP Biopsy Port Seal (ACMI Corporation) was performed. Usability was evaluated via insertion/extraction forces and insertion time for instruments, including a straight tip sensor wire, 0.035″, (Boston Scientific), a laser fiber (Flexiva 200, Boston Scientific), and an Ngage Nitinol Stone Extractor 1.7F (Cook Urological) through a flexible ureteroscope (Olympus URF P5, Olympus). Flow rate, flow time, and user fatigue were tested for two irrigation systems: The single action pumping system (SAP, Boston Scientific) and the Pathfinder Plus (PP, Utah Medical Products). The US needed the shortest time for both wire insertion and basket insertion (P=0.005, and P<0.001, respectively), while the BSS needed the greatest time for laser fiber insertion (P<0.005). The REF ABP needed the greatest force for withdrawal of the Ngage basket, the laser fiber, and the Captura stone grasper through a closed seal, while the US took the least amount of force for both laser fiber withdrawal and insertion via analysis of variance. Leak point pressure assessment demonstrated that the US was leak free at irrigation pressures up to 200 mm Hg, while the ABP, BSS, and the REF ABP devices demonstrated leaks ranging from 30 to 200 mm Hg. The average and peak flow of the SAP were significantly higher than that of the PP. Mean grip strength decreased significantly after operation of the SAP for 10 minutes, while no loss of grip strength was observed after use of the PP. The US valve has the advantage of facile manipulation of wires and baskets while maintaining a watertight seal, while other devices may be more cost-effective and secure. The PP has the advantage of less operator hand fatigue and ease of use, but the SAPS may allow for greater on-demand pressures. Further studies are needed to evaluate the effect of these irrigation systems on outcomes.

Outcomes of Flexible Ureterorenoscopy and Laser Fragmentation for Renal Stones: Comparison Between Digital and Conventional Ureteroscope

To compare the outcomes of flexible ureterorenoscopy and lasertripsy (FURS) using digital and conventional FURS for kidney stones. From September 2007 to April 2011, 118 patients underwent FURS (by the same surgeon). The outcomes were compared between equal numbers of procedures (59 each) using a conventional flexible ureterorenoscope (C-FURS; Olympus URF-P5) and a digital flexible ureterorenoscope (D-FURS; Olympus URF-V). Although the deflection, working channel, and field view are similar in both, the initial and terminal diameter is 8.4F and 9.9F and 6.9F and 8.4F for the D-FURS and C-FURS, respectively. The mean stone fragmentation time was calculated by the size per operative time. The preoperative, operative, and postoperative data were retrospectively analyzed and compared. The patient demographics were comparable. The mean stone size was 12.8 and 12 mm in the C-FURS and D-FURS groups, respectively. The initial assessment of the entire pyelocaliceal system was possible in 58 of 59 cases (98%) in the C-FURS group and 56 of 59 cases (94%) in the D-FURS group. The mean operative time was significantly longer in the C-FURS group (53.8 ± 15.2 minutes vs 44.5 ± 14.9 minutes). The overall stone-free rate 1 month after the procedure was 86% in the C-FURS group and 88% in the D-FURS group. Although on comparison, the D-FURS had slightly limited maneuverability, comparable success rates can be achieved with both conventional and digital ureteroscopes. D-FURSs significantly reduced the operative time compared with C-FURSs.

Successful outcome of flexible ureteroscopy with holmium laser lithotripsy for renal stones 2 cm or greater

Although percutaneous nephrolithotomy has been recommended as the first-line treatment for renal stones larger than 2 cm, its major complication rate is not negligible and less invasive approaches are to be explored. Thanks to the recent advances in endoscopic technology, flexible ureteroscopy has become another option in this setting. Herein we report our most recent experience with flexible ureteroscopy for large renal stones. Between September 2008 and May 2011, 20 patients with renal stones ≥ 2 cm underwent a total of 28 procedures of ureteroscopy with holmium laser lithotripsy, using the Olympus URF-P5 and a ureteral access sheath. The number of procedures, operative time, stone-free rates, stone compositions and complications were evaluated. Stone-free status was defined as the absence of fragments or fragments of ≤ 4 mm. Mean stone size was 3.1 cm (range 2.0-5.0). The average number of procedures was 1.4. One, two and three procedures were required in 13, six and one patients, respectively. Overall, the stone-free rate was 90%. The stone-free rate for preoperative stone size of 2 to ≤ 4 cm and >4 cm was 100% (14/14) and 67% (4/6), respectively. No major intraoperative complications were identified. Postoperative high-grade fever was observed in three patients, including one patient who developed sepsis. All these patients were successfully treated conservatively. Our findings suggest that ureteroscopy represents a favorable option for selected patients with renal stones, especially those 2 to ≤ 4 cm in size.

The Digital Flexible Ureteroscope: In Vitro Assessment of Optical Characteristics

Recent advances in endoscope design have placed the charged coupled device chip on the tip of the endoscope. The image is instantly digitalized and converted into an electrical signal for transmission. Digital technology was first introduced into flexible cystoscopes/nephroscopes and subsequently into rigid and flexible ureteroscopes. Herein, we assess the image characteristics and advantages of a new generation of digital flexible ureteroscopes. The Olympus URF-V flexible digital ureteroscope and the Olympus URF-P3 fiberoptic ureteroscope were assessed in vitro for image resolution, distortion, color representation, grayscale imaging, field of view, and depth of field. The digital ureteroscope had a higher resolution at 3, 5, 10, and 20 mm (25.2 lines/mm vs. 8.0, 14.1 vs. 5.0, 6.3 vs. 2.8, and 3.2 vs. 1.3), respectively. Distortion with the digital flexible ureteroscope was lower, though not statistically significant. Color representation was better with the digital ureteroscope, whereas contrast evaluation was comparable between both scopes. The digital flexlible ureteroscope produced a 5.3 times larger image size compared with the standard fiberoptic flexible uretersocpe with a narrower field of view. The depth of field was limited by light and not the optic or the camera for both ureteroscopes. The development of digital flexible ureteroscopes represents a significant technological advance in urology. These devices offer significantly improved resolution and color reproduction as compared with traditional fiberoptic flexible ureteroscopes. Future clinical trials are warranted to ultimately determine the advantages of these innovative endoscopes.

Durability of the Next-generation Flexible Fiberoptic Ureteroscopes: A Randomized Prospective Multi-institutional Clinical Trial

To evaluate the durability of 4 next-generation flexible ureteroscopes in a randomized, multi-institutional, prospective study. Patients at 3 institutions were randomized to 1 of 4 flexible ureteroscopes: the Wolf Viper, Olympus URF-P5, Gyrus-ACMI DUR-8 Elite (DUR-8E), and Stryker FlexVision U-500. Each center used 1 scope from each manufacturer until it needed major repair (primary endpoint). Intraoperative data included total time of use, number of scope insertions through an access sheath, working time in the lower pole, number of insertions and total time for accessory instrumentation in the working channel, number of laser insertions through the working channel, and total laser energy used. A total of 175 patients were randomized. The DUR-8E experienced early catastrophic failure (< or = 10 cases) at all 3 sites; however, this also occurred at 1 site each for the Stryker and Wolf scopes. The DUR-8E required major repair after the fewest average number of cases (5.3), the lowest average total time of usage (108 minutes), the fewest insertions through an access sheath (20.3), the shortest duration of laser firing (31.3 minutes), and the shortest instrument in the working channel time (224.7 minutes). As such, due to variation in durability within manufacturers, no differences could be demonstrated. Visibility ratings for the Wolf iper were significantly better than the DUR-8E (P = .034) and the Flexvision (P = .038). The Wolf Viper, Olympus URF-P5, and Stryker Flexvision U-500 flexible ureteroscopes seem comparable with regard to durability. However, larger prospective registry-based studies are needed to document significant differences between them.

In Vitro Comparison of a Disposable Flexible Ureteroscope and Conventional Flexible Ureteroscopes

We compared and evaluated the objective characteristics (deflection characteristics, field of view and flow rate) of a disposable flexible ureteroscope and 6 established, commercially available flexible ureteroscopes. Six commonly used ureteroscopes, including Olympus URF-P3, Storz(R) 11278AU and 11274AAU, ACMI DUR-8 Elite and DUR-8, and Wolf 7331.001 (Richard Wolf Medical Instruments, Vernon Hills, Illinois), were compared with the recently introduced SemiFlex Scope disposable flexible ureteroscope. Specifications and purchase costs were acquired from each manufacturer. The disposable ureteroscope consisted of a reusable eyepiece and a semiflexible shaft with a 3.3Fr working channel. Active tip deflection was measured with and without the 3Fr basket, the 365 mum laser fiber and the 3Fr forceps. The flow rate and field of view of each scope were evaluated. Active tip deflection (down/up) was highest in the disposable ureteroscope at 300/265 degrees. Although deflection was decreased by inserting the different endoscopic tools in all ureteroscopes, the disposable ureteroscope had the highest loss in flexion characteristics (35.7% down and 39.3% up). The flow rate, measured at 25 ml per minute in the disposable ureteroscope, was significantly lower than that of other ureteroscopes. The disposable ureteroscope had a 72-degree field of view, comparable to the optical characteristics of the other scopes. Compared to the other 6 flexible ureteroscopes the purchase price of the disposable scope was significantly lower and no further maintenance/repair expenses were required. The disposable flexible ureteroscope has acceptable active tip deflection, field of view and flow rate compared to those of other flexible ureteroscopes on the market. Further evaluation of surgical outcomes will help delineate the definitive usefulness of the disposable flexible ureteroscope.

COMPARISON OF FLEXIBLE URETEROSCOPES: DEFLECTION, IRRIGANT FLOW AND OPTICAL CHARACTERISTICS

We measured and compared the deflection, irrigation flow rates, distortion, resolution and light transmission of new generation flexible ureteroscopes. Multiple characteristics of 5 flexible ureteroscopes (ACMI DUR-8 Elite, Olympus URF-P3, Storz 11278AU1 [Flex-X], Wolf 7330.072 and Wolf 7325.172) commonly available in the market were measured and compared. Measured data included active deflection, irrigation flow rates and optical characteristics. Each ureteroscope was evaluated with an empty working channel and with various accessories. Optical characteristics, specifically resolution and distortion, were measured using test targets (Edmund Optics, Barrington, New Jersey). Light transmission was also measured from the ureteroscope tip at 50% and 100% intensity. All 5 flexible ureteroscopes were tested in a laboratory setting using a Storz OR 1 system to capture the images. For all 5 ureteroscopes the angle of deflection was most impaired by a 365 microm laser fiber probe and least impaired by a 2.2Fr nitinol basket. Among all 5 ureteroscopes irrigation flow rate was most impaired with a 3.0Fr basket and least impaired with 200 microm laser fiber. The Wolf 7325.172 had the highest observed resolution of 25.39 lines per mm and the Wolf 7330.072 had the lowest distortion at 11.9%. The Karl Storz Flex-X and the ACMI DUR-8 Elite had the highest light output at 374 and 364 mV, respectively. The various flexible ureteroscopes differ with regard to flow rates as well as degree of deflection with either an empty or an occupied working channel. The Wolf flexible ureteroscope with a slightly larger working channel and a fused quartz bundle provided for superior flow and better optical performance. However, the greatest amount of tip deflection and highest light output were found in the ACMI and Karl Storz flexible ureteroscopes.

Performance and Durability of Leading Flexible Ureteroscopes

The role of ureteronephroscopy in the diagnosis and treatment of upper-tract disease has expanded dramatically in recent years with technological advances. In a study involving 14 urologists, we measured the practical performance and durability of the most common commercially available flexible ureteroscopes. Six commercially available flexible ureteroscopes (Circon-ACMI DUR 8, ACMI DUR 8-Elite, Storz 11274AA, Wolf 7325.172-7.5Fr, Wolf 7330.072-9.0 Fr, Olympus URF-P3) were used consecutively 102 times over a 7-month period. Comparative data, including preoperative and postoperative maximal deflection angles and luminosity, were accumulated, as well as a survey of insertion methods, irrigation methods, instruments used in the working channel, visibility, maneuverability, and overall satisfaction. Maintenance records were analyzed to evaluate the need or reason for repair. Overall satisfaction, visibility, luminosity, and maneuverability were similar for all instruments. The ACMI DUR-8 Elite scored slightly higher than the others, but the difference was not statistically significant. Ureteroscopes were used an average of 10 to 34 times between breakages. The ACMI DUR-8 and DUR-8 Elite instruments had a higher durability score than the others, but with significantly more uses. Channel perforation by a laser fiber was the predominant cause of ureteroscope breakage. All ureteroscopes performed similarly by objective and subjective criteria. The largest and newest instruments were significantly more durable than the smaller ones, even in the hands of numerous endoscopists. This finding has significant implications for the cost-effectiveness of the various ureteroscopes.

Is there a role for small-diameter ureteral access sheaths? Impact on irrigant flow and intrapelvic pressures

Objectives To evaluate irrigant flows and intrapelvic pressures with small-diameter access sheaths. Ureteral access sheaths improve irrigant flow and decrease intrarenal pelvic pressures during flexible ureteroscopy. However, no comparisons of individual sheaths have been conducted. Previous studies have demonstrated more favorable results with the 12F sheath than with the 10F sheath. Methods Ureteral access sheaths were tested ex vivo in porcine kidneys. An 18F angiocatheter was placed in the renal pelvis and connected to a Hewlett Packard Gauss Pressure transducer. Irrigant was maintained at 100 mm Hg pressure. Irrigant flow and intrapelvic pressures were measured with three flexible ureteroscopes at baseline and using each of four 10F sheaths, with the sheaths positioned in the middle ureter and the ureteroscopes positioned in the renal pelvis. The pressure at which irrigant efflux through the sheath occurred and the rate of irrigant efflux through the access sheath were measured. Results Intrapelvic pressures measured greater than 40 mm Hg, and irrigant flows remained at less than 15 mL/min when the Olympus URF-P3 and Storz 11274AAU flexible ureteroscopes were tested with all four sheaths. The intrapelvic pressures, irrigant inflow, and irrigant efflux with the Wolf 7325.172 (7.5F) flexible ureteroscope were optimized in combination with the Cook Peelaway 10F and Applied Access 10F sheaths. Conclusions Small ureteral access sheaths should be used only with the Wolf 7325.172 flexible ureteroscope. The Cook Peelaway (10F) and Applied Access (10F) sheaths offered the greatest increase in irrigant flow and decrease in intrapelvic pressures.

Flexible ureterorenoscopy: prospective analysis of the Guy's experience.

To report our outcomes with small diameter, actively deflectable flexible ureterorenoscopy from a prospective database. 114 flexible ureterorenoscopies were performed in 105 patients (mean age, 49.5 years; range, 19-85 years; 71 males, 34 females) over a 9-month period. Of these, 101 were for refractory stones following failed ESWL and 13 for diagnostic reasons. An Olympus URF P3 flexible ureteroscope with pressure irrigation was used. Electrohydraulic lithotripsy was used to fragment stones and the fragments were retrieved with Graspit, triradiate graspers or tipless baskets. Stents had previously been placed in 53% and dilatation of the ureteric orifice was necessary in 15%. In the stone group, the median operating time was 55 min (range, 15-210 min) and the median screening time 2.2 min (range, 0.3-9.1 min). Success was defined as complete stone clearance or good fragmentation to 2 mm or less. Overall success in this group was 72.3%. There was no statistically significant difference between lower and other calyces (P=0.83 Chi-square test). Successful outcome was achieved in 72% for stone size 10 mm or less, 80% for 11-20 mm and 50% for greater than 20 mm. Two or more procedures were needed in 8 patients. In the diagnostic group, the median operating time was 45 min (range, 20-60 min) and the median screening time 2 min (range, 0.3-8.3 min). The majority were for upper tract filling defects. Access and successful diagnosis was achieved in all cases. The major complication rate was 2.6%. The ureteroscope needed repair once during this series. Flexible ureterorenoscopy is an effective diagnostic and therapeutic tool in a select group of patients. It should be considered for ESWL-resistant upper tract stones but the results are poor in stones larger than 20 mm and percutaneous nephrolithotomy may be a better option in these patients.

Physical properties of flexible ureteroscopes: implications for clinical practice.

Physical characteristics may be important in the performance of a flexible ureteroscope. This study evaluated the strength of the shaft and deflection mechanism of several instruments. Sequential loads were placed along the axis of downward deflection to measure the stiffness of the shaft and strength of deflection. Bending pressure was defined as the force required to deflect the tip of the ureteroscope 15 degrees from baseline. Buckling pressure was defined as the force that resulted in catastrophic bending (>90 degrees) of the shaft of the ureteroscope. Strength of deflection was defined as the force that resulted in loss of 10 degrees of active deflection. Bending pressures were lower for the Olympus URF-P3 (6.4 g) and Wolf 7325.172 (6.0 g) ureteroscopes. Similarly, buckling pressures were lower for these two ureteroscopes (9.0 g and 11.6 g, respectively). The Wolf and Storz flexible ureteroscopes had stronger deflection mechanisms than the Olympus URF-P3 and the ACMI DUR-8. This study demonstrates significant differences in ureteroscope strength. Higher buckling pressures may facilitate advancement of a ureteroscope over a guidewire but may impede secondary deflection. Lower bending pressures may facilitate passive intrarenal manipulation. Strength of deflection may impact the ability to maintain deflection with an instrument in the working channel.

Comparison of the mechanical, flow, and optical properties of contemporary flexible ureteroscopes

Objectives New designs have improved the ability of flexible ureteroscopes to assess the upper urinary tract. However, limitations of tip deflection may interfere with diagnosis and treatment of lower pole renal pathologic features and smaller working channels may impair irrigant flow. Our purpose was to compare the new flexible ureteroscopes with prior models to determine whether engineering advances have overcome these problems. Methods Two newly released flexible ureteroscopes, the ACMI DUR-8 Elite and the Storz 11278AU, were compared with four other ureteroscopes, the ACMI DUR-8, Storz 11274AAU, Olympus URF-P3, and Wolf 9F. Active tip deflection, irrigation flow rates, and intraluminal pressures with and without various endoscopic tools were assessed. The specifications, purchase prices, and repair costs were obtained from the individual manufacturers. Also, the field of view and screen image size of each scope were compared. Results The ACMI DUR-8 Elite and Storz 11278AU had improved tip deflection of 79° and 144°, respectively, from previous ureteroscopes. Although the tip deflections of all ureteroscopes were compromised by the insertion of endoscopic tools, new ureteroscopes were less affected. With a 3F basket within the working channel, the ACMI DUR-8 Elite and the Storz 11278AU had a loss of downward deflection of only 0.7% and 2.8% compared with a loss of 9.6% and 5.0% for their older models, respectively. However, the flow rate of these new instruments was decreased. Conclusions The new flexible ureteroscopes have significantly better active tip deflection than previous models, both with and without endoscopic instrumentation inserted. However, improved flexibility comes at the expense of a decreased flow rate.