中国医疗器械杂志最新文献

More than 70% of tumor patients require radiotherapy. Medical electron linear accelerators are important high-end radiotherapy equipment for tumor radiotherapy. With the application of artificial intelligence technology in medical electron linear accelerator, radiotherapy has evolved from ordinary radiotherapy to today's intelligent radiotherapy. This study introduces the development history, working principles and system composition of medical electron linear accelerators. It outlines the key technologies for improving the performance of medical linear electron accelerators, including beam control, multi-leaf collimator, guiding technology and dose evaluation. It also looks forward to the development trend of major radiotherapy technologies, such as biological guided radiotherapy, FLASH radiotherapy and intelligent radiotherapy, which provides references for the development of medical electron linear accelerators.

In the field of medical devices, there has been a long-term lack of a general technical requirements framework for reliability that can be applied in the development of high-risk active implantable medical devices. This study combines the requirements of YY/T 1837-2022 to comprehensively explain and explore the requirements for reliability work that can be performed at each stage of development of active implantable medical device products, and provides a reference for product reliability work in the industry.

Objective: A quality control (QC) system based on the electronic portal imaging device (EPID) system was used to realize the Multi-Leaf Collimator (MLC) position verification and dose verification functions on Primus and VenusX accelerators.

Methods: The MLC positions were calculated by the maximum gradient method of gray values to evaluate the deviation. The dose of images acquired by EPID were reconstructed using the algorithm combining dose calibration and dose calculation. The dose data obtained by EPID and two-dimensional matrix (MapCheck/PTW) were compared with the dose calculated by Pinnacle/TiGRT TPS for $\gamma$ passing rate analysis.

Results: The position error of VenusX MLC was less than 1 mm. The position error of Primus MLC was significantly reduced after being recalibrated under the instructions of EPID. For the dose reconstructed by EPID, the average $\gamma$ passing rates of Primus were 98.86% and 91.39% under the criteria of 3%/3 mm, 10% threshold and 2%/2 mm, 10% threshold, respectively. The average $\gamma$ passing rates of VenusX were 98.49% and 91.11%, respectively.

Conclusion: The EPID-based accelerator quality control system can improve the efficiency of accelerator quality control and reduce the workload of physicists.

Based on preprocessed MRI images of low back pain patients, this study extracted MRI image features that can reflect the dysfunction of low back pain patients, and proposed a stacking ensemble learning algorithm model based on algorithm diversity, which provided a reliable method and an implementation method for the accurate assessment of limb dysfunction in low back pain patients.

Based on the original data of cervical spine, the models of cervical C6 and C7 segments were reconstructed through medical image processing and reverse modeling operations, then the models were assembled to obtain the basic data of interbody fusion cage. According to the basic data, the structures of rectangular porous, gradient porous and octahedral porous interbody fusion cages were established respectively. Maximum force on the adult male neck was applied to the fusion device, and the stress, strain and maximum deformation of the fusion device were solved by finite element analysis. The elastic modulus decrease of the design, and the rectangular porosity structures with different porosity were analyzed and optimized. The results showed that the elastic modulus of the fusion cage with three structures decreased in varying degrees, and the porosity of the interbody fusion cage with rectangular structure was about 60%, which was the most decreased elastic modulus.

Objective: To explore the effect of routine reusable pipeline and disposable pipeline on ventilator quality control results.

Methods: 17 ventilators were randomly selected to conduct quality control using routine reusable pipeline and disposable pipeline respectively. Quality control data were recorded and then paired t-test method was used to analyze whether the difference between the two pipelines was significant or not.

Results: There were no significant differences in respiratory rate, tidal volume and end airway pressure between the two types of pipes ( P＞0.05). The airway peak pressure of routine reusable pipeline was significantly higher than disposable pipeline ( P＜0.05), but the difference was very small, only about 0.2 mbar which would not affect the conclusion of quality control.

Conclusion: Quality control of ventilator is not affected by routine reusable pipeline and disposable pipeline, which can be replaced by each other.

Naked-eye 3D display technology has excellent 3D visual effects and does not require wearable devices assistance. It can present the depth, position and complex structure information of 3D medical images, allowing viewers to obtain information about tissues and organs from different points, reducing cognitive load, contributing to medical teaching and opening up innovative methods for planning and diagnosis. Naked-eye 3D augmented reality display can display medical images in real 3D space, achieving virtual and real vision. It helps a lot to medical research. The applications of naked-eye 3D display technology in three major aspects of medical diagnosis, clinical surgery and rehabilitation training is reviewed in the study. It provides the direction for the subsequent research in medical field, thus assisting medical research and improving medical practice.

The critical control points in the production quality management of metal additive manufacturing medical devices, including personnel, hardware, design and development, procurement control, production management and quality control are summarized from the perspective of supervision. The typical cases are analyzed to provide reference for medical device regulatory authorities and enterprises.

To investigate the value of self-developed air-free laparoscopic auxiliary instruments in the clinical application of thyroid diseases. The clinical data of 70 transaxillary and 45 transareolar air-free laparoscopic surgeries for thyroid cancer and 40 conventional open surgeries were retrospectively compared. The transaxillary and transareolar laparoscopic groups had significantly longer operative times than the open group, while the postoperative satisfaction was higher in the endoscopic group than in the open group. This set of instruments has advantage of novel design, scientific structure, safe application. It can be compatible with a variety of thyroid and breast air-free laparoscopic procedures, which can promote the development and popularization of laparoscopic technology.

An early warning system of sudden cardiac death based on the Internet electrocardiograph and intelligent platform is designed to detect the signal of sudden cardiac death in time and save lives. The system is mainly composed of four parts: Internet electrocardiograph, mobile terminal, intelligent platform and 120 emergency center. It has been verified that the sudden cardiac death early warning system is reliable, suitable for remote electrocardiogram monitoring, and can provide diagnosis and early warning for people at risk of sudden cardiac death. The system realizes the miniaturization of ECG monitoring equipment, and has the advantages of intelligent diagnosis and rapid warning, and can be applied to the pre-hospital monitoring of high-risk groups of sudden cardiac death and has a good application value.