The article introduces the clinical testing method for the product of patient monitor, the definition of direct measurement and indirect measurement method, and the different testing methods. The clinical testing methods for none invasive blood pressure, pulse oxygen saturation and ECG analysis have significant value, which are important solutions to test the safety and effectiveness of medical devices by using the equivalent analysis method. These methods above are also provided as reference for other medical devices' clinical testing.
Equipment Failure Analysis ; Equipment Safety ; Equipment and Supplies ; standards ; Humans

In an effort to overcome the drawbacks of distraction osteogenesis using the Ilizarov external fixator, intramedullary lengthening devices have been developed and applied for long bone distraction osteogenesis. Several successful cases have been reported, leading to the next generation of distraction osteogenesis. However, intramedullary lengthening devices have their own problems, such as device failure, difficulty of control of the lengthening degree. The authors report on a case of device failure during distraction osteogenesis using ISKD(R) (Orthofix Inc.) in the distraction phase, and the strategy that involved switching to a lengthening over nail system, which uses the Ilizarov external fixator, in order to obtain the target length.
Equipment Failure ; Equipment Failure Analysis ; External Fixators ; Osteogenesis, Distraction*

In this paper, the common errors in medical devices test reports are classified and analyzed. And then the main 11 influence factors for these inspection report errors are summarized. The hierarchy model was also developed and verified by presentation data using MATLAB. The feasibility of comprehensive weights quantitative comparison has been analyzed by using the analytic hierarchy process. In the end, this paper porspects the further research direction.
Equipment Failure Analysis ; Equipment and Supplies ; standards ; Models, Theoretical

According to the structural characteristics of spiral CT systems and our experiences, some relevant solutions to common malfunctions in daily maintenance are suggested.
Computers ; Equipment Design ; Equipment Failure ; Equipment Failure Analysis ; methods ; Humans ; Maintenance ; Tomography, Spiral Computed ; instrumentation

An introduction of an intelligent testing instrument for medical electrical equipment security is given in this article. The realization of its testing functions is based on a single-chip processor, the high-voltage control circuit and the relay combination network technology. It can be used to test security parameters such as the continuous leakage current, patient auxiliary current, dielectric strength and protective earth impedance. It is suitable for the medical electricity security testing of Kind I, II and Type B, BF, CF (internal power supply) medical electrical equipments.
Electricity ; Equipment Design ; Equipment Failure Analysis ; instrumentation ; methods ; Equipment Safety ; instrumentation ; methods ; Software Design

To evaluate the fatigue behavior of nitinol stents, we used the finite element method to simulate the manufacture processes of nitinol stents, including expanding, annealing, crimping, and releasing procedure in applications of the clinical treatments. Meanwhile, we also studied the effect of the crown area dimension of stent on strain distribution. We then applied a fatigue diagram to investigate the fatigue characteristics of nitinol stents. The results showed that the maximum strain of all three stent structures, which had different crown area dimensions under vessel loads, located at the transition area between the crown and the strut, but comparable deformation appeared at the inner side of the crown area center. The cause, of these results was that the difference of the area moment of inertia determined by the crown dimension induced the difference of strain distribution in stent structure. Moreover, it can be drawn from the fatigue diagrams that the fatigue performance got the best result when the crown area dimension equaled to the intermediate value. The above results proved that the fatigue property of nitinol stent had a close relationship with the dimension of stent crown area, but there was no positive correlation.
Alloys ; Computer Simulation ; Equipment Failure Analysis ; Finite Element Analysis ; Stents

This article reviews the recent progress of the finite element analysis (FEA) researches focusing on various expansion types, fatigue durability and the flexibility of the stents.
Equipment Failure Analysis ; Finite Element Analysis ; Prosthesis Design ; Stents

Based on the structure and principle of transducers for medical ventilators, this paper analyzes the causes of transducers' failures, and introduces some corresponding calibration methods. Besides, some suggestions about how to reduce different kind of transducer failures are put forward.
Calibration ; Equipment Failure ; Equipment Failure Analysis ; methods ; standards ; Equipment Safety ; methods ; Maintenance ; Respiration, Artificial ; instrumentation ; Transducers ; Ventilators, Mechanical

The AB 7300 Real-time PCR Systems in our hospital have been detected malfunction for three times in a short term. The detection indicated the major reason for the malfunction attributed to the fuse of the solder of the COVER at the same position with the serial number 4344490 D1. This article explicitly introduces how to detect and maintain this equipment. It serves as a good reference for colleagues. Meanwhile the author raises five issues for further exploration and discussion.
Equipment Failure Analysis ; Maintenance ; methods ; Polymerase Chain Reaction ; instrumentation ; methods

The aim of this study was to compare the accuracy of four different methods for measuring wear using an apparatus that simulates known amounts of three dimensional wear. Wear was measured using the manual methods reported by Charnley, Livermore, Dorr and Wan and the computerized method reported by Devane. Only the method reported by Devane measured the three-dimensional (superior and anterior) wear with a reasonable accuracy, with a mean measurement error of 0.21 mm. With superior wear alone, Charnley's method underestimated the extent of wear by 16.6%, with a mean error of 0.35 mm; Livermore's method estimated wear to within 9.5%, with a mean error of 0.16 mm; Devane's method estimated wear to within 9.5%, with a mean error of 0.15 mm; and Dorr's method underestimated wear by 25.4%, with a mean error of 0.56 mm. Dorr's method was modified as a result of the experimental tests. The clinical application of the new method showed comparable data to that using the Devane method. In conclusion, this new method can be used to estimate the average wear in groups of patients accurately.
Equipment Failure Analysis/instrumentation/methods ; *Hip Prosthesis ; Human ; *Polyethylene ; *Prosthesis Failure ; Stress, Mechanical