Prediction of microvascular invasion in hepatocellular carcinoma with magnetic resonance imaging using models combining deep attention mechanism with clinical features / 南方医科大学学报

OBJECTIVE@#To investigate the consistency and diagnostic performance of magnetic resonance imaging (MRI) for detecting microvascular invasion (MVI) of hepatocellular carcinoma (HCC) and the validity of deep learning attention mechanisms and clinical features for MVI grade prediction.@*METHODS@#This retrospective study was conducted among 158 patients with HCC treated in Shunde Hospital Affiliated to Southern Medical University between January, 2017 and February, 2020. The imaging data and clinical data of the patients were collected to establish single sequence deep learning models and fusion models based on the EfficientNetB0 and attention modules. The imaging data included conventional MRI sequences (T1WI, T2WI, and DWI), enhanced MRI sequences (AP, PP, EP, and HBP) and synthesized MRI sequences (T1mapping-pre and T1mapping-20 min), and the high-risk areas of MVI were visualized using deep learning visualization techniques.@*RESULTS@#The fusion model based on T1mapping-20min sequence and clinical features outperformed other fusion models with an accuracy of 0.8376, a sensitivity of 0.8378, a specificity of 0.8702, and an AUC of 0.8501 for detecting MVI. The deep fusion models were also capable of displaying the high-risk areas of MVI.@*CONCLUSION@#The fusion models based on multiple MRI sequences can effectively detect MVI in patients with HCC, demonstrating the validity of deep learning algorithm that combines attention mechanism and clinical features for MVI grade prediction.

Evaluation of three predictive models of knowledge-based treatment strategies for radiotherapy / 中华放射肿瘤学杂志

Objective:To compare the accuracy and generalized robustness of three predictive models of knowledge-based treatment strategies for radiotherapy for optimized model selection.Methods:The clinical radiotherapy plans of 45 prostate cancer (PC) cases and 25 nasopharyngeal cancer (NPC) cases were collected, and analyzed using three models (Z, L and S model), proposed by Zhu et al, Appenzoller et al and Shiraishi et al, respectively, to predict the dose-volume histogram (DVH) of bladder and rectum on PC cases and that of left and right parotid on NPC cases. The prediction error was measured by the difference of area under the predicted DVH and the clinical DVH curves (|V (pre_DVH)-V (clin_DVH)|), where a smaller prediction error implies a greater prediction accuracy. The accuracies of these three models were compared on the single organ at risk (OAR), and the generalized robustness of models was evaluated and compared by calculating the standard deviation of the prediction accuracy on different OAR. Results:For bladder and rectum, the prediction error of L model (0.114 and 0.163, respectively) was significantly higher than those values of Z and S models (≤0.071, P<0.05); for left parotid gland, the predicted error of S model (0.033) did not present significant difference from those values of Z and L models (≤0.025, P>0.05); for right parotid gland, S model (0.033) demonstrated significantly higher prediction error than those of Z and L models (≤0.028, P<0.05). Regarding different OAR, S model showed a lower standard deviation of prediction accuracy when comparing to Z and L models (0.016, 0.018 and 0.060, respectively). Conclusions:In the prediction of DVH in bladder and rectum of PC, Z and S models were more accurate than L model. In contrast, Z and L models demonstrated higher accuracy than S model in the prediction of left and right parotid glands of NPC. In respect to different OAR, the generalized robustness of S model was superior than the other two models.

Design of Smart Care Tele-Monitoring System for Mother and Fetus / 中国医疗器械杂志

<p><b>OBJECTIVE</b>To study and design a maternal and fetal monitoring system based on the cloud computing and internet of things, which can monitor and take smart care of the mother and fetus in 24 h.</p><p><b>METHODS</b>Using a new kind of wireless fetal monitoring detector and a mobile phone, thus the doctor can keep touch with hospital through internet. The mobile terminal was developed on the Android system, which accepted the data of fetal heart rate and uterine contraction transmitted from the wireless detector, exchange information with the server and display the monitoring data and the doctor's advice in real-time.</p><p><b>RESULTS</b>The mobile phone displayed the fetal heart rate line and uterine contraction line in real-time, recorded the fetus' grow process. It implemented the real-time communication between the doctor and the user, through wireless communication technology.</p><p><b>CONCLUSIONS</b>The system removes the constraint of traditional telephone cable for users, while the users can get remote monitoring from the medical institutions at home or in the nearest community at any time, providing health and safety guarantee for mother and fetus.</p>

Development of a new type intelligent high potential therapeutic apparatus / 生物医学工程学杂志

This article presents the development and design of a new type intelligent high potential therapeutic apparatus, by using Atmega1280 as its controller. The circuit transforms voltage from 220 V ac to 110 V ac and constitutes different circuits with relays. In order to get different treatment waveforms, inductance of various values is used in different circuits. The circuit generates appropriate treatment voltage with the transformer booster. Simultaneously, the corresponding control software was composed. Finally the hardware and software designs of the high potential therapeutic apparatus were completed. Result of the experiment showed that the high potential therapeutic apparatus worked steadily and the effect of treatment was satisfactory.

Positioning errors of CT common rail technique in intensity-modulated radiotherapy for nasopharyngeal carcinoma / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the value of CT common rail technique for application in intensity-modulated radiotherapy for nasopharyngeal carcinoma (NPC).</p><p><b>METHODS</b>Twenty-seven NPC patients underwent Somatom CT scans using the Siemens CTVision system prior to the commencement of the radiotherapy sessions. The acquired CT images were registered with the planning CT images using the matching function of the system to obtain the linear set-up errors of 3 directions, namely X (left to right), Y (superior to inferior), and Z (anterior to posterior). The errors were then corrected online on the moving couch.</p><p><b>RESULTS</b>The 27 NPC patients underwent a total of 110 CT scans and the displacement deviations of the X, Y and Z directions were -0.16∓1.68 mm, 0.25∓1.66 mm, and 0.33∓1.09 mm, respectively.</p><p><b>CONCLUSION</b>CT common rail technique can accurately and rapidly measure the space error between the posture and the target area to improve the set-up precision of intensity-modulated radiotherapy for NPC.</p>

Design of the multi-functional bone forceps characterized by gripping, bending and cutting / 生物医学工程学杂志

We have designed a sort of multi-functional bone forceps for use as orthopedic surgical instruments to grip, bend and cut the spicula. It is labor-saving and easily installed. Its left and right clamp bodies are connected by a rivet to hold the spicula, and the pressure-regulating shank is connected with the clamp seat body at the right top of the clamp body by a rivet. It is used to curve the spicula. At an appropriate location on the pressure-regulating shank is a pin-cutting chip. On the right body rotating disc-clamp, there is a rectangular open cutting groove to be in use for cutting the specula with the role of pin-cutting chip. Being characterized by the use of mechanical leverage, the manipulations of holding and bending are less arduous. After achieving the 90-degree bend, the operator can cut off the specula successfully. The operation is easy to perform and labor-saving; the forceps can further meet the actual clinical demand.

Development of a new head and neck location frame for PET and CT cross-modality medical image fusion in radiotherapy / 生物医学工程学杂志

A new head and neck location frame for positron emission tomography (PET) and computed tomography (CT) cross-modality medical image fusion in radiotherapy was developed. The solid mark bars of N form in the old designed CT location frame were replaced by closed hollow pipes which could be filled with different developer solutions before CT or PET scan, respectively. Nine points of external marker used for registration and fusion were obtained in CT images and PET images, respectively. The locations of the two sets of nine points showed the method of registration to be effective and accurate in achieving the PET and CT image fusion. This method, based on its characteristics of simple structure and easy-to-use, can be of wide application in clinical setting.

Design of a mechanical system for the balanceable system of ambulance / 生物医学工程学杂志

This is the design of a mechanical systems for use in the balanceable system of ambulance, which can keep the medical service bed at the ambulance level, whatever the terrain is. A level detector will detect the level state of the bed and turn it to a signal. The central processing unit will use this signal to analyse and control the movement of the motor. By this design (which uses the rolling rail as a drive transmission and makes three supports of the bed go up and down), the bed will keep level. With the use of this design, the balanceable system of ambulance can counteract 35 degrees. The error is controlled within +/- 1 degree. And the response time is within 0.3 s. The method of registration can be effective for keeping the bed at the ambulance level, and for reducing the chance of making the patient get hurt on the way to hospital.

A novel mechanical orientation system used for body precise radiotherapy / 生物医学工程学杂志

In the end of last century, there was a leap in the technological quality of radiotherapy, which is incarnated in three new technologies: Stereotactic radiation surgery (SRS), three-dimensional conformal radiation therapy (3D-CRT) and intensity modulated radiation therapy (IMRT). However, the achievement of these technologies has a close relationship with the precise orientation of tumour. Especially, in terms of body stereotactic precise radiation therapy, its body mechanical orientation system is the kernel to guarantee the accuracy of radiotherapy. This paper presents a novel mechanical orientation system for body precise radiotherapy. It is characterized by flexible adjustment, deft removal, easy disassembly and accurate orientation using apart structure to substitute old integer structure and adopting single segment Z shape orientation marker staff. The new mechanical orientation system guarantees the effect of tumour radiotherapy, which is worthy to be recommended for clinical use.

Research and experiment of compensator made by split method for static intensity-modulated radiation therapy / 医疗卫生装备

Objective To help the hospitals at all levels in China to realize IMRT by adding the accurate location equipments and TPS based on the existing general radiation therapy from research of the new method for static Intensity-modulated radiation therapy. Method Based on the controlled technique of CRT, a new split method for fabricating the three-dimensional physics compensator to achieve the IMRT was developed. Results The Experiment manifested that the compensator fabricated by the way could make the high dosage shape of target in accordance with the form of tumor and could adjust the distribution of the dosage according to remedy requirement. Conclusion The method is simple and feasible, and has brilliant clinical prospective and popularized significance.

Research of the refrigeration system of a new field portable blood refrigerator / 医疗卫生装备

This paper develops the refrigeration system of a new field portable b lood refrigerator. Based on inverse heat leak test, the hardcore of thermoelectr ic refrigerator and the match of the system are determined, and several key fact ors of refrigeration effect are analyzed. In the aspects of framework, size and noise, the blood refrigerator with a thermoelectric refrigeration system is bett er than the traditional one with a compress refrigeration system.

A Study on IMRT Beam Weight and Orientation Optimization based on Genetic Algorithm with Two Populations / 医疗卫生装备

Objective To study the application of the genetic algorithm with two populations in optimization of both IMRT beam weight and orientation.Methods The genetic algorithm with two populations was used to optimize IMRT beam weight and orientations with three dimensional pencil beam dose calculation model. The algorithm was implemented in Visual c#. Net. And the results were analyzed. Results The modest change of the beam orientation resulted in more conformal dose distribution in target volume, and large high dose area was included. Further more, genetic algorithm with two populations gave such a clinically acceptable computation time. Conclusion Little change had distinct influence on dose distribution when there were few beam orientations. The genetic algorithm with two populations was an effective and global optimization method because of its parallel, robust and global. It provided satisfying results when used to optimize IMRT beam weight and orientations

A Method for Calculating Scatter Dose of Irregular Fields / 实用放射学杂志

Objective To find a method for calculating the scatter dose of irregular fields. Methods The original Day function was improved to vary with radiation depth, and the improved Day function was used for irregular fields to calculate scatter dose. Results The accuracy was greatly improved by making Day function depend on radiation depth, and the error was within 1.5%. Conclusion This method can be used to calculate the scatter dose of irregular fields as well as rectangular fields.

Variational Model on Wavelet Domain for PET/CT Image Fusion / 医疗卫生装备

Objective To find a new algorithm for PET/CT image fusion.Methods A variational model was used based on the wavelet transform.Firstly,PET and CT images were decomposed using wavelet transform.Then,images in approximate channel and detail channel were fused according to the two proposed assumption.Finally,decomposed images were synthesized to form fused image.Results Compared with the results form MATLAB wavelet fusion toolbox,the experimental results showed that the new variational image fusion model could provide more accurate result for target location in radiotherapy planning.Conclusion According to experiments,the new algorithm can reach good results and meet requirement of clinical demands.

Selection of CR and DR / 医疗卫生装备

Selection of CR and DR is very important for digital radiology departments in modern hospitals. This paper discusses the components of CR and DR as well as their technical requirements.

Development of Long Pulse YAG Laser Treatment Machine / 医疗卫生装备

Objective To develop a laser treatment machine for the benign prostatic hyperplasia(BPH),which can both avoid the transurethral resection symptoms(TURS) and rapidly remove the big BPH.Methods The machine adopted a long plus laser with 80W average power and 1000W peak value power in order to rapidly vaporize the neoplasm.Because of its high power,short operation time and small thermal penetraction depth,it could avoid the post-operation edema of the organ is resulted from the concretion of traditional continuous-wavelength YAG laser.The control system based on AT89C51 dominated the laser power,and meanwhile,it monitored the process to protect the machine.It was connected with the Hospital Information System(HIS) via RS232.Results The chicken breast tissues were irradiated with the sample machine under water,and the groove irradiated by laser was 4mm in width and 2.5mm in depth with the irradiation speed of 5mm/s.The arbonation of tissue surface was slight and the thermal damage to the adjacent tissues was the minimal.Conclusion This machine can rapidly vaporize the neoplasm with the minimal thermal damage to the adjacent non-irradiated tissues.It is desirable for the treatment of big BPH.

Research on control circuit of a new CT simulation laser positioning system / 医疗卫生装备

CT laser simulation positioning system is a necessary auxiliary device for radiotherapy. Its main purpose is to position patients by simulating different kinds of treatment machine. In order to demarcate the mark of the iso-center, it is common to use the laser positioning device to indicate the iso-center. The kernel technology of the laser positioning system is the controlling of the step progress motor by using the MCS, which is to control the movement of step progress motor using the wheel of the motor. This design uses MCS-51 to control step progress motor by the way of exporting the rectangle wave form through I/O port of 8255 chip. The system configuration is simple, the operation is convenient and the positioning is precise.