中国医疗器械杂志最新文献

The gradual acceleration of the aging population in China has led to an increased demand for mobility aids, and the reliability of domestic wheeled walking-aid is one of their important attributes, but there is little research on the reliability of mobility aids. This paper conducts the failure mode, effects and criticality analysis on domestic wheeled walking-aid. By collecting, collating and analyzing the 26 failure modes, the key modules are the chassis and the lifting system. The key modules are obtained, and the failure data is analyzed to find out that the lifetime distribution model is log-normal and the 0.95 lower confidence limit for reliability life of product t _0.9 is 2489.4 hours. The study aims to provide ideas for the reliability analysis of other active medical devices and calls for the formation of a reliability study review point for the industry that meets the requirements of Chinese medical device regulations.

Through the effective application of Essential Principles of Safety and Performance of Medical Devices and IVD Medical Devices (EP), to continuously improve the corresponding management tools to ensure the safety and effectiveness of medical device in the quality management system, risk management system, evaluation of safety and effectiveness for the supervision departments and manufacturers. The current status of the application of EP and the application issues are analyzed in the study. Take artificial joint products for example, the idea of using EP in quality management system, risk management system and evaluation of safety and effectiveness is investigated, and several thoughts are proposed. Supervision departments should strengthen the unified understanding of EP, develop requirements according to the classification of medical device，and refine specific execution requirements.

This study conducted statistics on the special review applications for Class Ⅱ innovative medical devices in Shanghai from April 2020 to April 2023. It summarized and analyzed common problems in the innovation review application stage, and gave suggestions for applicants and reviewers in order to further improve the quality of innovation application and improve the pass rate of innovation applications.

Different porous structures were studied through finite element analysis and then optimal porous structure was selected for the orthopedic applications. The optimal Voronoi structure was designed and fabricated using 3D printing. The mechanical properties and osseointegration ability were both investigated. The mechanical tests showed that the tensile strength, compressive strength and bending strength of Voronoi structures were obviously higher than that of the human bone, and the modulus of Voronoi structures were similar to human bone. In addition, the animal experimental results exhibited that obvious bone ingrowth was found from Month 1 to Month 6. This study provides some theoretical references for the orthopedic application of porous structures.

The development history of pMBRT, the biological role of minibeam, the mechanism of minibeam protection of tissues, the generation of minibeam (collimator method and magnetic focusing method), and the analysis of advantages and disadvantages of proton minibeam matrix arrays is introduced with advanced proton minibeam arrays (pMBRT). It is proposed that the combination of proton minibeam arrays and magnetic resonance fields can help to exploit the normal tissue protective function of pMBRT, and improve the precision of proton therapy.

Adhesives have emerged as an effective method for wound closure, hemostasis and tissue engineering in recent years, which not only are suitable for the adhesion of wet tissues, but also can adapt to the peristalsis and mechanical stretching of tissues and organs, especially for arteries and organize bleeding. With the further development of technology, existing adhesives can be modified through different strategies, and new materials are explored, giving new properties and uses to adhesives, such as drug delivery, temperature sensitivity, light sensitivity and so on. Nevertheless, there are many questions about the design and practical clinical application of adhesives in the future. The recent research progress of traditional adhesives and their application in hemostasis is reviewed, and the design and development ideas of future adhesives are discussed in the study.

Vector flow imaging (VFI) is an innovative ultrasound flow measurement technology. Compared with the traditional color Doppler and spectral Doppler, VFI has the advantages of independence of angle correction and direct acquisition of real-time amplitude and direction of flow. Transverse oscillation (TO) method is one of the effective methods for vector flow imaging. However, a complete and detailed algorithm validation process based on commercial ultrasound machines is still lacking due to more complex convex probes. This study starts with introducing the imaging process and principle of transverse oscillation vector flow technique, and calculates the error between the set velocity value and the measured velocity value through the simulation experiment, and verifies the error between the set velocity value and the measured velocity value through the Doppler flow phantom experiment. Among them, the velocity value measured by the TO vector flow technique in the simulation experiment is 0.48 m/s and the preset value is 0.50 m/s, the error between them is -4%. The velocity values are 8.33, 11.14, 14.44 and 16.67 cm/s measured by the Doppler flow phantom experiment, the actual velocity values are 7.97, 10.78, 14.06 and 17.34 cm/s, the errors between them are all within ±5%. Both experiments verify the feasibility of using vector flow technique on abdominal convex probe.

In the past 20 years, near infrared spectrum technology has been widely used in human body monitoring due to its non-invasive and real-time characteristics. Oxygen, as the main metabolic substance of the human body, is consumed the most in brain tissue. In order to prevent complications caused by a decrease in brain tissue oxygen during treatment, the patient's brain tissue blood oxygen saturation needs to be monitored in real time. Currently, most of the clinically used non-invasive cerebral blood oxygen detection equipments use dual wavelengths. Other substances on the detection path will cause errors in the measurement results. Therefore, this article proposes a three-wavelength method based on the basic principle of non-invasive monitoring of cerebral blood oxygen using near-infrared spectrum. The brain tissue oxygen saturation monitoring method of detecting light sources was initially verified through the built system, laying the foundation for subsequent system engineering.

The monitoring unit used in the nuclear magnetic resonance system, as an important unit of the system, faces a high thermal risk during its entire life cycle. This paper ensures the high efficiency and reliability of the thermal design of the product module from the two dimensions of structural design and device derating design. In order to reduce the risk of thermal design of electronic modules and comprehensively verify the effectiveness of thermal design of electronic modules, the design verification is carried out by combining simulation and experiment. In the simulation process, by establishing a thermal simulation model at the circuit board level, the crustal temperature of the core device is numerically calculated, and the index is compared with the thermal design index value and the test value, on the one hand, to verify the correctness of the simulation model. On the other hand, the validity of thermal design is verified. In the testing process, a thermal test platform for product modules is built, and the thermal characteristics test values of the core components of the module under extreme electrical conditions are obtained, and the corresponding conversion methods are used to predict the thermal performance and thermal design margin of the product at different altitudes. The results show that the electronic module can meet the thermal design requirements in terms of structural design and derating design of core components, and can ensure that the product module can work safely and reliably during the entire life cycle of the NMR system.

Vascular cognitive impairment（VCI） is a group of syndromes ranging from mild cognitive impairment to dementia caused by cerebrovascular disease, due to the lack of sensitivity and specific biomarkers, it is difficult to identify and diagnose early. Abnormal connectivity is observed in brain regions of patients with vascular cognitive disorders, locates mainly in the default mode network（DMN）, and changes in their abnormal functional connectivity correlated with the degree of patients' cognitive impairment. Resting-state functional magnetic resonance imaging(rs-fMRI) is a commonly used method to detect the internal activity of the brain at resting state. The use of various rs-fMRI to study abnormal changes in the DMN in patients with VCI is useful to further investigate the pathogenesis of VCI and provide an objective basis for imaging. This article mainly reviews the application of rs-fMRI in the DMN in patients with VCI, bringing new perspectives for the correct diagnosis and assessment of VCI.