Endoscope Damage Research Articles

MP68-01 PATTERN ANALYSIS OF LASER FIBER DEGRADATION ACCORDING TO THE LASER SETTING: IN VITRO STUDY OF THE DOUBLE-FIRING PHENOMENON

You have accessJournal of UrologyCME1 Apr 2023MP68-01 PATTERN ANALYSIS OF LASER FIBER DEGRADATION ACCORDING TO THE LASER SETTING: IN VITRO STUDY OF THE DOUBLE-FIRING PHENOMENON Sang Won So, Gyoohwan Jung, Hyeji Park, and Sung Yong Cho Sang Won SoSang Won So More articles by this author , Gyoohwan JungGyoohwan Jung More articles by this author , Hyeji ParkHyeji Park More articles by this author , and Sung Yong ChoSung Yong Cho More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003331.01AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: It is essential to understand the mechanism of the various causes of laser fiber damage and an ideal method of reducing endoscope damage induced by laser emission in multiple sites. This study classified the different patterns of laser fiber degradation according to laser settings and analyzed the role of cavitation bubbles to find a desirable way of minimizing endoscope damage. METHODS: A total of 118 laser fibers were analyzed after 1-,3-, and 5-min laser emission to artificial stones under the settings of 1J-10Hz, 1J-20Hz, 1J-30Hz, and 2J-10Hz. Every 3cm from the fiber tip was marked and examined with a digital microscope and a high-speed camera. The images of the fibers and the movement of cavitation bubbles were taken with a distance of 1 to 5 mm from the gel. RESULTS: Seven types of fiber damage (charring, limited and extensive peeled-off, bumpy, whitish plaque, crack, and break-off) coincided during laser emission. Damages rapidly increased with emission time>3 min regardless of the laser settings. The damaged lengths covered 5 mm on average, and the fibers at 5-min emission were significantly shorter than others. The fiber durability of 1J-10Hz setting was better than other settings after 3-min laser emission. Backward movement of the cavitation bubbles was found at the 1-mm distance from the gel, and the damaged lengths were longer than the diameters of the cavitation bubbles because of their proximal movement. CONCLUSIONS: The damage patterns of the laser fiber tips were classified into seven types. The heat damage around the surface of the laser fiber can be increased according to the high-energy or high-frequency laser setting, a short distance to the stone, a short distance from the tips of flexible ureteroscopes, no cutting laser fiber procedures, and the inappropriate use of irrigation fluid or laser fiber jacket. Source of Funding: This work was supported by a grant No. 2019R1C1C1008339 mainly and another one No. 2017R1A2B3007907 in part of the National Research Foundation (NRF) grant funded by the Korean government (MSIT) © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e952 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Sang Won So More articles by this author Gyoohwan Jung More articles by this author Hyeji Park More articles by this author Sung Yong Cho More articles by this author Expand All Advertisement PDF downloadLoading ...

Pattern Analysis of Laser Fiber Degradation According to the Laser Setting: In Vitro Study of the Double-Firing Phenomenon.

BackgroundIt is essential to understand the mechanism of the various causes of laser fiber damage and an ideal method of reducing endoscope damage induced by laser emission in multiple sites. This study classified the different patterns of laser fiber degradation according to laser settings and analyzed the role of cavitation bubbles to find a desirable way of minimizing endoscope damage.MethodsA total of 118 laser fibers were analyzed after 1-,3-, and 5-min laser emission to artificial stones under the settings of 1 J-10 Hz, 1 J-20 Hz, 1 J-30 Hz, and 2 J-10 Hz. Every 3 cm from the fiber tip was marked and examined with a digital microscope and a high-speed camera. The images of the fibers and the movement of cavitation bubbles were taken with a distance of 1 to 5 mm from the gel.ResultsSeven types of fiber damage (charring, limited and extensive peeled-off, bumpy, whitish plaque, crack, and break-off) coincided during laser emission. Damages rapidly increased with emission time > 3 minutes regardless of the laser settings. The damaged lengths covered 5 mm on average, and the fibers at 5-min emission were significantly shorter than others. The fiber durability of 1J-10Hz setting was better than other settings after 3-min laser emission. Backward movement of the cavitation bubbles was found at the 1-mm distance from the gel, and the damaged lengths were longer than the diameters of the cavitation bubbles because of their proximal movement.ConclusionThe damage patterns of the laser fiber tips were classified into seven types. The heat damage around the surface of the laser fiber can be increased according to the high-energy or high-frequency laser setting, a short distance to the stone, a short distance from the tips of flexible ureteroscopes, no cutting laser fiber procedures, and the inappropriate use of irrigation fluid or laser fiber jacket.

Small-caliber endoscopes are more fragile than conventional endoscopes.

Background and study aims The repair costs of gastrointestinal endoscopes account for a significant proportion of the total budget of an endoscopy unit. This study evaluated the repair costs of small-caliber endoscopes and conventional endoscopes used in esophagogastroduodenoscopy (EGD). Patients and methods A retrospective analysis of upper gastrointestinal endoscope damage and repair costs between April 2012 and May 2019 was performed at the Toyoshima Endoscopy Clinic. Conventional endoscopes (GIF-H260, GIF-HQ290, and GIF-H290Z) were used for transoral EGD while small-caliber endoscopes (GIF-XP260N and GIF-XP290N) were used for transnasal or transoral EGD. Results Three small-caliber endoscopes and five conventional endoscopes were used for 1,031 procedures and 31,192 procedures, respectively. The number of procedures/damage incidence for small-caliber endoscope and conventional endoscopes was 344 and 1950, respectively. Damage incidence for small-caliber endoscopes was significantly higher than for conventional endoscopes ( P = 0.014). Repair costs/procedure were $ 5.95 ± $132 for small-caliber endoscopes and $2.41 ± $115 for conventional endoscopes. Repair costs/procedure for small-caliber endoscopes were more than twice those for conventional endoscopes. Conclusions Small-caliber endoscopes are more fragile than conventional endoscopes.

Application effect analysis of details management on endoscope management in operating room

Objective To study the details management measures of endoscope management in operating room to analyze the management method and effect of reducing endoscope damage. Methods A total of 1 200 operations implemented in the operating room of our hospital from January to March, 2015 were selected as observation group, and details management was conducted to the endoscope instruments of operating room. 1200 operations from October to December, 2014 were selected as the control group. The aspects of instrument cleaning and disinfection acceptability, instrument perfectness rate and the occurrence rate of instrument preparation error of operations in observation group were compared with 1200 operations before details management was conducted. Meanwhile, the satisfaction of surgeon to the implementation of details management was observed. Results After details management was implemented, the instrument cleaning and disinfection acceptability, instrument perfectness rate and the occurrence rate of instrument preparation error of operations in two groups had significant difference. The observation group was obviously superior to control group (P<0.05), and the difference was statistically significant. Conclusions The effective details management conducted to operation endoscope in operating room can significantly improve the nursing quality. Moreover, the perfectness rate of surgical cavity mirror instruments and acceptability of instrument cleaning and disinfection can be improved. In addition, the occurrence of instrument preparation error will be reduced effectively and the satisfaction of surgeon to the operation nursing will be increased significantly. Therefore, the implementation of details management in operating room is of great significance. Key words: Operating room; Endoscopic management; Detail management

Assessing residual contamination and damage inside flexible endoscopes over time.

Researchers evaluated flexible endoscope damage and contamination levels at baseline and 2 months later. Postcleaning test results exceeded benchmarks for all gastroscopes and no colonoscopes. Microbial growth was found in samples from 47% of fully reprocessed endoscopes at baseline and 60% at follow-up. Borescope examinations identified scratches, discoloration, debris, and fluid inside endoscopes. Irregularities changed over time. Study evaluations allowed damaged and contaminated endoscopes to be identified and re-reprocessed or sent for repairs.

Clinical Issues—September 2016

Packaging multiple items in a single peel pouch Key words: peel pouch, packaging, low profile items. Closed instruments found in instrument trays Key words: closed instruments, instrument trays. Organic and inorganic material found in instrument trays Key words: organic material, inorganic material, instrument trays. Processed endoscopes touching each other Key words: endoscope storage, endoscopes touching, endoscope storage cabinet, endoscope damage, endoscope coiling. Maximum safe storage time for processed flexible endoscopes Key words: endoscope storage, endoscope storage time, risk assessment, multidisciplinary team.

Extractable fragment versus dusting during ureteroscopic laser lithotripsy in children: Prospective randomized study

Complete eradication of stone fragments is an important goal during stone management in children. The mode of fragmentation employed to clear stones during ureteroscopic laser lithotripsy raises concerns related to operative time, associated morbidity, costs, and especially potential endoscope damage. The purpose of this study was to evaluate the outcomes of fragmentation into extractable pieces and stone dusting during ureteroscopic laser lithotripsy in children. One hundred children with ureteral stones undergoing ureteroscopic holmium laser lithotripsy were prospectively randomized into two groups: group I in which stones were fragmented to dust (n=50), and group II in which lithotripsy resulted in extractable fragments (n=50). Different Holmium laser settings were applied during ureteroscopic lithotripsy for each group: low power (500mJ) and high frequency (12-15Hz) for lithotripsy to dust. High power (1000-1500mJ) and reduced frequency (8-10Hz) for lithotripsy to extractable fragments. The fragmentation time, operating time, stone-free rate, and perioperative complications were compared (Figure). The mean age of the patients was 6.8 (1-12) years and 8.2 (1-15) years, in groups I and II respectively. The mean fragmentation time and operating time were statistically significantly lower in group II (p=0.008 and 0.0069 respectively). Minor complications occurred in eight cases (5 in group I and 3 in group II) in the form of hematuria and urinary tract infection. No major complications were encountered in either groups. Fragmenting stones into extractable pieces has a significantly shorter fragmentation time and operative time than stone dusting, with similar stone-free and complication rates. Ureteroscopic laser lithotripsy treatment resulting in extractable fragments seems to be an effective and time-saving procedure in children.

Assessment of Competence in Simulated Flexible Bronchoscopy Using Motion Analysis

Background: Flexible bronchoscopy should be performed with a correct posture and a straight scope to optimize bronchoscopy performance and at the same time minimize the risk of work-related injuries and endoscope damage. Objectives: We aimed to test whether an automatic motion analysis system could be used to explore if there is a correlation in scope movements and the operator's level of experience. Our hypothesis was that experienced bronchoscopists move less and keep the flexible scope straighter than less-experienced bronchoscopists while performing procedures. Methods: Eleven novices, 9 intermediates and 9 experienced bronchoscopy operators performed 3 procedures each on a bronchoscopy simulator. The Microsoft Kinect system was used to automatically measure the total deviation of the scope from a perfectly straight, vertical line. Results: The low-cost motion analysis system could measure the accumulated deviation of the scope precisely during the procedure. The deviations were greatest for the novices and smallest for the most experienced operators for all 3 procedures (p = 0.01, p = 0.01 and p = 0.04, respectively). The total deviation from the straight scope correlated negatively with the performance on the simulator (virtual-reality simulator score; p < 0.001). Conclusion: The motion analysis system could discriminate between different levels of experience. Automatic feedback on correct movements during self-directed training on simulators might help new bronchoscopists learn how to handle the bronchoscope like an expert.

Evaluation of a New 240-μm Single-Use Holmium:YAG Optical Fiber for Flexible Ureteroscopy

Numerous holmium:yttrium-aluminum-garnet laser fibers are available for flexible ureteroscopy. Performance and durability of fibers can vary widely among different manufacturers and their product lines with differences within a single product line have been reported. We sought to evaluate a newly developed nontapered, single-use 240-μm fiber, Flexiva™ 200 (Boston Scientific, Natick, MA), during clinical use and in a bench-testing model. A total of 100 new fibers were tested after their use in 100 consecutive flexible ureteroscopic lithotripsy procedures by a single surgeon (B.K.). Prospectively recorded clinical parameters were laser pulse energy and frequency settings, total energy delivered and fibers failure. Subsequently, each fiber was bench-tested using an established protocol. Parameters evaluated for were fibers true diameter, flexibility, tip degradation, energy transmission in straight and 180° bend configuration and fibers failure threshold with stress testing. The mean total energy delivered was 2.20 kJ (range 0-18.24 kJ) and most common laser settings used were 0.8 J at 8 Hz, 0.2 J at 50 Hz, and 1.0 J at 10 Hz, respectively. No fiber fractured during clinical procedures. The true fiber diameter was 450 μm. Fiber tips burnt back an average of 1.664 mm, but were highly variable. With laser setting of 400 mJ at 5 Hz, the mean energy transmitted was 451 and 441 mJ in straight and 180° bend configuration, respectively. Thirteen percent of fibers fractured at the bend radius of 0.5 cm with a positive correlation to the total energy transmitted during clinical use identified. Fiber performance was consistent in terms of energy transmission and resistance to fracture when activated in bent configuration. Fiber failure during stress testing showed significant correlation with the total energy delivered during the clinical procedure. The lack of fiber fracture during clinical use may reduce the risk of flexible endoscope damage due to fiber failure.

Reply to Hu

I appreciate the comments raised by Dr Hu regarding the method I described for transferring a nasobiliary tube from the mouth to the nose, and especially the concerns raised about nasal trauma and endoscope damage. Our patient was actually edentulous, though a bite block was in place nonetheless. The self-limited nasal bleeding our patient experienced may also have been due to the prior unsuccessful attempt at passage of the transfer tube. Using the technique I described the assistant at the head of the bed needs to ensure that the bite block is not expelled if moderate sedation or monitored anesthesia care is administered.

Thulium Fiber Laser Ablation of Urinary Stones Through Small-Core Optical Fibers

Complications during laser lithotripsy include optical fiber bending failure resulting in endoscope damage and low irrigation rates leading to poor visibility. Both problems are related to fiber diameter and limited by the holmium:YAG (Ho:YAG) laser (lambda = 2120 nm) multimode beam profile. This study exploits the thulium fiber laser (lambda = 1908 nm) beam profile for higher power transmission through smaller fibers. Thulium fiber laser radiation with 1 ms pulse duration, pulse rates of 10-30 Hz, and 70-mu m-diameter spot was coupled into silica fibers with 100, 150, and 200 mum core diameters. Fiber transmission, bending, and endoscope irrigation tests were performed. Damage thresholds for 100, 150, and 200 mum fibers averaged 40, 60, and > 80 W, respectively. Irrigation rates measured 35, 26, and 15 mL/min for no fiber, and 100 and 200 mum fibers. Thulium fiber laser energy of 70 mJ delivered at 20 Hz through a 100 mum fiber resulted in vaporization and fragmentation rates of 10 and 60 mg/min for uric acid stones. The thulium fiber laser beam profile provides higher laser power through smaller fibers than Ho:YAG laser, potentially reducing fiber failure and endoscope damage, and allowing greater irrigation rates for improved visibility.

Frequency and Costs of Echo Endoscope Repairs: Results of a Survey of Endosonographers

The need for repair of endoscopic ultrasound (EUS) equipment appears to be frequent and expensive. To better quantify the costs associated with echo endoscope failure, a survey of endosonographers was carried out. A survey questionnaire concerning echo endoscope damage and repair and consequences of echo endoscope downtime over a 12-month period was sent to members of the American Society of Gastrointestinal Endoscopy who had cited an interest in EUS. Responses were received from 56 of 138 institutions where EUS was carried out (41 %). A median of 325 EUS procedures had been carried out in the past year and a median of two endosonographers were employed who used an average of three echo endoscopes. Two-thirds of institutions trained fellows. A total of 225 repairs were reported for leaks (47 %), mechanical failures (33 %), images or optics difficulties (26 %), or other problems (1 %). Mechanical radial-scanning echo endoscopes tended to break, on average, after 68 procedures, while curved linear-array echo endoscopes failed after an average of 107 procedures. Echo endoscope failures led to rescheduling of procedures at three-quarters of institutions. Institutions paid an average of $ 10 534 over 12 months for echo endoscope repairs. The average repair cost per procedure was $ 41. There was an inverse relationship between quantity of procedures and the per-procedure repair rate ( P < 0.05). Direct and indirect costs of echo endoscope repairs are significant. Instrument failures are multifactorial; however instrument complexity, instrument age, and institutional inexperience may contribute to repair costs.

Mycobacteria and glutaraldehyde: is high-level disinfection of endoscopes possible?

Background: High-level disinfection of endoscopes has traditionally been undertaken by manual or automatic scope cleaning plus a 10 to 20 minute soak in 2% alkaline glutaraldehyde. Mycobacteria species are less sensitive to glutaraldehyde, and a 45-minute instrument soak has recently been recommended by the manufacturer. Because of concerns over endoscope damage, need for more endoscopes, and perception that the current cleaning method is adequate, we prospectively studied mycobacteria-contaminated endoscopes at various stages of the cleaning process. Methods: All work was done under a laminar flow hood in a microbiology laboratory. Five gastrointestinal scopes were contaminated with 10 8 colony forming units per milliliter (CFU/mL) of Mycobacterium chelonei, an atypical mycobacterium similar in chemical resistance to Mycobacterium tuberculosis but with less infectious potential. Cultures of the sheath, biopsy channel, and elevator channel were taken at baseline, after manual cleaning, and after 10, 20, and 45 minutes of glutaraldehyde soak both before and after alcohol rinse. Results: Manual cleaning resulted in a mean of 4.7 log 10 reduction in viable mycobacterial colonies. Qualitative studies of the external endoscope surface as well as the air-water valve showed no detectable organisms after a 10-minute exposure to alkaline glutaraldehyde. Conventional quantitative culture techniques of the channels demonstrated one endoscope out of five with consistent growth after a 10-minute exposure to glutaraldehyde. Following alcohol treatment, there was no significant colony growth. In contrast, a quantitative membrane filter system showed the presence of at least one mycobacterial colony in four out of five scopes after a 45-minute glutaraldehyde exposure. Conclusions: Additional studies utilizing a standardized mycobacterial species, inoculum size, and suspension characteristics are recommended to delineate adequate duration of disinfectant exposure time. (Gastrointest Endosc 1996;43:451-6.)