1.Digital X-ray Machine Carestream DRX-NOVA Fault Maintenance.
Chinese Journal of Medical Instrumentation 2023;47(1):115-118
OBJECTIVE:
To analyze the malfunction and maintenance process of Carestream digital X-ray machine DRX-NOVA for reference.
METHODS:
The fault of Carestream digital X-ray machine DRX-NOVA in 2011-2021 was summarized, the fault types were classified, and the maintenance process was summarized.
RESULTS:
Fault types can be divided into three categories, each of which has its own characteristics and specific solutions.
CONCLUSIONS
It is necessary to master the principle of equipment to repair all kinds of equipment failures. Repair the machine should be careful, comprehensive consideration of the cause of the failure. To correctly understand and analyze the operation of the machine under normal conditions, we can accurately analyze the cause of failure, so that we can really solve the problem.
X-Rays
;
Radiography
;
Radiographic Image Enhancement
;
Equipment Failure
2.Analysis of Performance of the MINItrace Cyclotron before and after Upgrade.
Xiaofeng ZHANG ; Zhenjiang GAO ; Shuai LI ; Jianwei YANG
Chinese Journal of Medical Instrumentation 2020;44(1):92-94
OBJECTIVE:
To compare the performance of the GE cyclotron MINItrace system before and after the upgrade.
METHODS:
The upgrade of the MINItrace system included replacing the silver target with the Nb syetem and adopting the latest RF control and management system and lastest ion source system.The failrue rate and production efficiency were retrospectively analyzed before and after the upgrade.
RESULTS:
After the upgrade, the cyclotron failure rate decreased by 86.2%, the average capacity increased by 45%.
CONCLUSIONS
After the upgrade of MINItrace cyclotron, the failure rate is sharply reduced, and the production efficiency is grately improved.
Cyclotrons/standards*
;
Equipment Failure
;
Retrospective Studies
3.Summary of Fault Maintenance Experience of Multifunctional Digital Flat Plate Radiography System-Carestream DR7500.
Liangning YU ; Zhicheng YANG ; Junjie ZHANG ; Haiyan JING
Chinese Journal of Medical Instrumentation 2020;44(5):467-470
This paper is a summary of the three types of faults that have occurred in the recent years in the Carestream DR7500:hardware failure, software failure, and communication failure. The specific cases of three types of faults are introduced in a case-by-case basis.
Equipment Failure
;
Maintenance
;
Radiographic Image Enhancement
4.General Troubleshooting and Preventive Maintenance of the Digestive Electron Microscope System.
Yewei WANG ; Guoqing XU ; Jun FAN ; Chai YANG
Chinese Journal of Medical Instrumentation 2019;43(5):388-390
OBJECTIVE:
Improve the integrity of the digestive electron microscope equipment and reduce the cost of equipment failure maintenance.
METHODS:
By studying the composition and function of the digestive electron microscope system and analyzing the causes of common faults, a targeted preventive maintenance plan is developed, equipment users are graded, and a training system is established.
RESULTS:
The user of the device can skillfully analyze the cause of the malfunction and timely deal with the sudden failure of the diagnosis and treatment, thereby reduce the risk of diagnosis and treatment and the investment in hospital maintenance.
CONCLUSIONS
Through the analysis and processing of the digestive electron microscope system, point detection leakage, grading training, preventive maintenance can significantly improve the equipment integrity rate, reduce the risk of clinical diagnosis and treatment, effectively reduce the number of equipment failures, and reduce maintenance costs.
Equipment Failure
;
Maintenance and Engineering, Hospital
;
Microscopy, Electron
;
instrumentation
5.Research on Fault Risk Identification and Control of CT Simulator Based on FMEA.
Fan BI ; Haisheng HU ; Wenyong TU
Chinese Journal of Medical Instrumentation 2019;43(4):303-306
OBJECTIVE:
To explore the high-risk fault risk of CT simulator and the main causes of the risk, and to put forward effective risk management strategies.
METHODS:
The failure mode and effect analysis method was used to identify and control the operational fault risk of CT simulator.
RESULTS:
5 major fault components, 8 fault failure models and 17 failure causes were analyzed. The top 5 failure causes are:anode target surface burn caused by direct scanning without warming up the tube (590.4), tube failure (518.2), burnout of joints caused by aging of high voltage cables (424.2), motor carbon brush wear (304.8) and belt break (296.4).
CONCLUSIONS
The failure mode and effect analysis method can effectively identify the risk of equipment failure, and thus specifically formulate risk management and control measures to ensure the normal operation of equipment and the safety of doctors and patients.
Equipment Failure
;
statistics & numerical data
;
Humans
;
Risk Management
;
methods
;
Tomography, X-Ray Computed
;
standards
6.Design of an axial blood pump of diffuser with splitter blades and cantilevered main blades.
Guangmao LIU ; Jian XI ; Haibo CHEN ; Yan ZHANG ; Jianfeng HOU ; Jianye ZHOU ; Hansong SUN ; Shengshou HU
Journal of Biomedical Engineering 2019;36(3):379-385
An implantable axial blood pump was designed according to the circulation assist requirement of severe heart failure patients of China. The design point was chosen at 3 L/min flow rate with 100 mm Hg pressure rise when the blood pump can provide flow rates of 2-7 L/min. The blood pump with good hemolytic and anti-thrombogenic property at widely operating range was designed by developing a structure that including the spindly rotor impeller structure and the diffuser with splitter blades and cantilevered main blades. Numerical simulation and particle image velocimetry (PIV) experiment were conducted to analyze the hydraulic, flow fields and hemolytic performance of the blood pump. The results showed that the blood pump could provide flow rates of 2-7 L/min with pressure rise of 60.0-151.3 mm Hg when the blood pump rotating from 7 000 to 11 000 r/min. After adding the splitter blades, the separation flow at the suction surface of the diffuser has been reduced efficiently. The cantilever structure changed the blade gap from shroud to hub that reduced the tangential velocity from 6.2 m/s to 4.3-1.1 m/s in blade gap. Moreover, the maximum scalar shear stress of the blood pump was 897.3 Pa, and the averaged scalar shear stress was 37.7 Pa. The hemolysis index of the blood pump was 0.168% calculated with Heuser's hemolysis model. The PIV and simulated results showed the overall agreement of flow field distribution in diffuser region. The blood damage caused by higher shear stress would be reduced by adopting the spindle rotor impeller and diffuser with splitter blades and cantilevered main blades. The blood could flow smoothly through the axial blood pump with satisfactory hydraulics performance and without separation flow.
China
;
Computer Simulation
;
Equipment Design
;
Heart Failure
;
therapy
;
Heart-Assist Devices
;
Hemolysis
;
Humans
;
Models, Cardiovascular
7.Efficiency of Air Bubble Removal in Preparation of Low-Profile Angioplasty Balloon Catheter: Bench-Top Comparison of Six Methods
Joon Ho CHOI ; Seon Moon HWANG ; Deok Hee LEE
Neurointervention 2019;14(1):27-34
PURPOSE: Complete removal of air bubbles from balloons for neurovascular angioplasty is cumbersome. We compared the preparation difficulty, air removal efficiency, and air collection pattern of six different balloon catheter preparation methods to propose a better preparation method for both initial and second balloon uses, especially for small-profile angioplasty balloon catheters. MATERIALS AND METHODS: A total of 18 neurovascular angioplasty balloon catheters with nominal diameters of 2 mm were prepared to test six different preparation methods: the instruction for use method (method A), simplified method using a syringe (method B) and four newly devised preparation methods using inflating devices (methods C–F). Serial radiographs were obtained while the balloons were gradually inflated. We measured the time for each preparation and the bubble number, analyzed their distribution in the balloon, and calculated the contrast filling ratio (contrast filling area/total balloon area) for initial and second ballooning. The whole process was repeated three times. RESULTS: The preparation time varied widely (11.5 seconds [method D] to 73.3 seconds [method A]). On initial inflation, the contrast filling ratio at 8 atm was the highest (100%) with methods A and F. On second inflation, the ratio was again highest with method A (99.5%), followed by method F (99.2%). Initial ballooning tended to show a uniform pattern of single bubble in the distal segment of the balloon; in contrast, second ballooning showed varying patterns in which the bubbles were multiple and randomly distributed. CONCLUSION: None of the six methods were able to completely exclude air bubbles from the balloon catheters including the second ballooning; however, the method of repeating aspiration with high-volume inflating device (method F) could be a practical option considering the simplicity and efficiency of preparation.
Angioplasty
;
Angioplasty, Balloon
;
Catheters
;
Clothing
;
Embolism, Air
;
Equipment Failure
;
Inflation, Economic
;
Intracranial Arteriosclerosis
;
Methods
;
Syringes
8.Feasibility of Revision Cochlear Implant Surgery for Better Speech Comprehension
Kyurin HWANG ; Jae Yong LEE ; Hyeon Seok OH ; Byung Don LEE ; Jinsei JUNG ; Jae Young CHOI
Journal of Audiology & Otology 2019;23(2):112-117
BACKGROUND AND OBJECTIVES: The purpose of this study was to evaluate the efficacy of revision cochlear implant (CI) surgery for better speech comprehension targeting patients with low satisfaction after first CI surgery. SUBJECTS AND METHODS: Eight patients who could not upgrade speech processors because of an too early CI model and who wanted to change the whole system were included. After revision CI surgery, we compared speech comprehension before and after revision CI surgery. Categoies of Auditory Performance (CAP) score, vowel and consonant confusion test, Ling 6 sounds, word and sentence identification test were done. RESULTS: The interval between surgeries ranged from eight years to 19 years. Same manufacturer’s latest product was used for revision surgery in six cases of eight cases. Full insertion of electrode was possible in most of cases (seven of eight). CAP score (p-value=0.01), vowel confusion test (p-value=0.041), one syllable word identification test (p-value=0.026), two syllable identification test (p-value=0.028), sentence identification test (pvalue=0.028) had significant improvement. Consonant confusion test (p-value=0.063), Ling 6 sound test (p-value=0.066) had improvement but it is not significant. CONCLUSIONS: Although there are some limitations of our study design, we could identify the effect of revision (upgrade) CI surgery indirectly. So we concluded that if patient complain low functional gain or low satisfaction after first CI surgery, revision (device upgrade) CI surgery is meaningful even if there is no device failure.
Cochlear Implants
;
Comprehension
;
Electrodes
;
Equipment Failure
;
Humans
9.The Present and Future of Vagus Nerve Stimulation
Journal of Korean Neurosurgical Society 2019;62(3):344-352
Epilepsy is one of the major chronic neurological diseases affecting many patients. Resection surgery is the most effective therapy for medically intractable epilepsy, but it is not feasible in all patients. Vagus nerve stimulation (VNS) is an adjunctive neuromodulation therapy that was approved in 1997 for the alleviation of seizures; however, efforts to control epilepsy by stimulating the vagus nerve have been studied for over 100 years. Although its exact mechanism is still under investigation, VNS is thought to affect various brain areas. Hence, VNS has a wide indication for various intractable epileptic syndromes and epilepsy-related comorbidities. Moreover, recent studies have shown anti-inflammatory effects of VNS, and the indication is expanding beyond epilepsy to rheumatoid arthritis, chronic headaches, and depression. VNS yields a more than 50% reduction in seizures in approximately 60% of recipients, with an increase in reduction rates as the follow-up duration increases. The complication rate of VNS is 3–6%, and infection is the most important complication to consider. However, revision surgery was reported to be feasible and safe with appropriate measures. Recently, noninvasive VNS (nVNS) has been introduced, which can be performed transcutaneously without implantation surgery. Although more clinical trials are being conducted, nVNS can reduce the risk of infection and subsequent device failure. In conclusion, VNS has been demonstrated to be beneficial and effective in the treatment of epilepsy and various diseases, and more development is expected in the future.
Arthritis, Rheumatoid
;
Brain
;
Comorbidity
;
Depression
;
Drug Resistant Epilepsy
;
Epilepsy
;
Equipment Failure
;
Follow-Up Studies
;
Headache Disorders
;
Humans
;
Seizures
;
Transcutaneous Electric Nerve Stimulation
;
Vagus Nerve Stimulation
;
Vagus Nerve
10.Research on Classifed Punishments on Manufacturers of Unconformity Products in Supervision and Sampling Inspection of Medical Devices.
Pei LI ; Xin LI ; Xiaolong QIANG ; Fenglian MA ; Zhiqiang WU
Chinese Journal of Medical Instrumentation 2018;42(6):440-443
Theories of classified management which are based on risk governance are introduced into the newly revised , but the punishments on the manufacturers of unconformity products are not classified based on the severity and risks caused by the test items. This article analysed the disadvantages of current punishment measures on the manufacturers of unconformity products and the theoretical basis of classified punishments. The feasibility of classified punishments had also been studied and some basis of discretionary punishments was provided under the current regulations.
Equipment Failure
;
Equipment and Supplies
;
standards
;
Punishment

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