中国医疗器械杂志最新文献

Objective: To evaluate the feasibility and accuracy of cone-beam CT (CBCT) images for radiotherapy dose calculation in pelvic tumors.

Methods: An improved volumetric density coverage method was used to establish CT value-relative electron density (RED) curves for CBCT images. The planning CT plans were transferred to the CBCT images, and the constructed density curves were applied to calculate doses for CBCT plans while maintaining the optimization parameters unchanged. Dose calculation deviations between the two plans were analyzed.

Results: The mean differences in dosimetric parameters for the target volume and organs at risk (OAR) between the two plans were less than 1% and 1.5%, respectively. The target conformity index (CI), homogeneity index (HI), and gamma passing rates were highly consistent, with no statistically significant differences.

Conclusion: CBCT images corrected by this method can be used for dose calculation in pelvic tumor radiotherapy planning.

Surgical robots represent one of the important diagnostic and treatment methods in the field of surgery. In recent years, artificial intelligence (AI) has been increasingly used in the field of surgical medicine, especially in the field of robotic-assisted surgery. This article reviews the common modes of AI in surgical robotics, enumerates the surgical robots available in the market, and summarizes some difficulties and challenges in the application of AI in surgical robotics through literature reviews, website visits and investor press releases analysis of target companies.

In order to improve the effect of transcranial electrical stimulation treatment and realize personalized treatment for patients with varying severity levels, this paper designed an integrated four-channel EEG recording multimodal transcranial electrical stimulation system. This system can conduct real-time monitoring on EEG and related characteristic analysis before stimulation, in stimulation, and after stimulation. This enables physicians and researchers to resolve real-time brain states, evaluate transcranial electrical stimulation effect, and then artificially adjust the stimulation parameters. After relevant testing and verification, the system can select four stimulation modes: TACS, TDCS, TPCS and TRNS, which can output the constant stimulation current of 0.03 mA accuracy in the range of ±2 mA and the stimulation frequency of low frequency of 0~4 kHz (precision of 0.01 Hz) and high frequency 50~100 kHz, which can obtain more accurate EEG signals under stimulation interference, demonstrating a good market application prospect.

This study investigated a novel coronary knobby scoring balloon through finite element analysis (FEA) and in vitro anti-slippage testing, evaluating its dilation process under various vascular conditions and comparing it with other balloons. The FEA results indicated that in the cases of healthy artery and diseased artery with different stenosis rates, the stress on the vessels caused by the knobby scoring balloon was significantly smaller than that of the scoring balloon, and was close to that of the plain balloon. In vitro anti-slippage testing showed that the slippage distance of a plain balloon was 0.11±0.06 mm, and there was no slippage for knobby scoring balloon under nominal pressure. Knobby scoring balloon can effectively expand calcified lesion while providing anti-slippage function, and has a lower risk of vascular injury.

This study aims to ensure the effectiveness of medical ultrasound diagnostic equipment in clinical applications by testing multiple key performance indicators using tissue-mimicking phantoms and exploring the changes in these performance indicators over time. Firstly, 17 in-service medical ultrasound diagnostic equipments were selected, and their depth of penetration, dead zone, lateral resolution, axial resolution, geometric position error, and cystic focal diameter error were tested according to the verification regulations. In addition, the study retrospectively analyzed the performance testing data of 19 medical ultrasound diagnostic equipments over the past three consecutive years and conducted statistical analysis. Through the testing, all performance indicators of the 17 equipments met the requirements of the verification regulations, indicating that they can stably and reliably provide high-quality ultrasound diagnostic images and data in clinical applications. Meanwhile, retrospective data showed that with the increase with the increase in service life, the resolving ability at the far field of the 19 equipments decreased, and the cystic focal diameter error increased. Therefore, it is recommended that medical institutions establish a regular testing and maintenance system for medical ultrasound diagnostic equipment, conducting regular performance evaluations and maintenance to ensure its good working condition.

Objective: The study investigates the performance parameters of a nebulizer for pressurized intraperitoneal aerosol chemotherapy (PIPAC).

Methods: Laser diffraction spectroscopy was used to measure the median droplet diameter ( D ₅₀) and spray angle during the steady-state aerosol phase.

Results: The minimum droplet diameter of aerosol was achieved when using a nozzle of 0.2 mm diameter and 0.07 mm thickness. The nebulizer could not produce steady-state aerosol when the liquid flow rate was less than or equal to 0.3 mL/s. When the liquid flow rate was greater than or equal to 0.5 mL/s, as the working pressure increased, the median particle size gradually decreased and the spray angle gradually increased. When the pressure is greater than or equal to 200 psi（1 psi=6 894.76 Pa）, as the liquid flow rate increased, the spray angle gradually increased. At a flow rate of 0.7 mL/s and working pressure of 300 psi, the median droplet diameter of aerosol D ₅₀ was 16 μm with a spray angle up to 89.2°.

Conclusion: As a novel intraperitoneal drug delivery technology, PIPAC requires further research focusing on reducing droplet size, expanding drug distribution, improving tissue permeability, and increasing drug concentration.

As a new type of high-risk packaging container, prefilled syringes are more widely used, and concerns regarding their effectiveness, stability and safety in clinical use have become prominent increasingly. However, the leachable substances from prefilled syringes may cause harm to humans in different degrees. Therefore, this paper reviews the research progress of leachable substances in prefilled syringes, which is not only of great significance for the quality control of prefilled syringe products, but also contributes to the healthy development of the industry.

To address the limitations of traditional minimally invasive thermal ablation technology such as poor conformability, carbonization and electromagnetic radiation, this paper proposes a steam thermal ablation technology that uses saturated steam internal energy to replace the traditional electromagnetic radiation energy. Through the steam thermal ablation system and the steam thermal ablation needle designed based on simulation, the ex vivo pig liver experiments were carried out. The results have the characteristics of the maximum ablation axis ratio (short diameter / long diameter) and non-carbonization with the same type of thermal ablation technology. Based on the near-infrared light, in this paper the curative effect of the reduced scattering coefficient of the steam thermal ablation results was evaluated. The reduced scattering coefficients of the coagulation area all exceeded 16, reaching the completely damaged state, which verified that the steam thermal ablation can effectively inactivate the tumor cells.

This study establishes a high-performance liquid chromatography (HPLC) method for the determination of acetate content in hemodialysis solutions and dialysis concentrates. In this study, Synergi Polar-RP column is utilized. Phosphate buffered saline (50 mmol/L, pH=2.5) is used as a mobile phase. The flow rate is 1.0 mL/min. The wavelength of detection is 212 nm. Results show that the linear relationship of acetate is good in the range of 0.1~20 mmol/L, r =0.999 9 and the spike recoveries are from 98.9%~99.5%, RSD<0.5% ( n=3). This method can easily and accurately determine the acetate content in hemodialysis solutions and dialysis concentrates, and can be applied to quality control in the production and use of such products.

In this study, the pre-market regulatory requirements for typical Class Ⅱ wound dressings, as well as the status of testing and post-market adverse events monitoring, were reviewed from the perspective of the whole lifecycle of medical devices. Additionally, the regulatory requirements for wound dressings in China, the United States, and the European Union were compared. Supplementary research was also conducted on Class Ⅰ and Ⅱ liquid and paste dressing products. Furthermore, this study analyzed the issues in the registration and application of typical Class Ⅱ wound dressings and provided regulatory recommendations, aiming to offer technical references for the review and approval, inspection and testing, and post-market supervision of wound dressing products.