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Pulmonary Edema and Pleural Effusion Detection Using Efficient Net-V1-B4 Architecture and AdamW Optimizer from Chest X-Rays Images
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作者 Anas AbuKaraki Tawfi Alrawashdeh +4 位作者 Sumaya Abusaleh Malek Zakarya Alksasbeh Bilal Alqudah Khalid Alemerien Hamzah Alshamaseen 《Computers, Materials & Continua》 SCIE EI 2024年第7期1055-1073,共19页
This paper presents a novelmulticlass systemdesigned to detect pleural effusion and pulmonary edema on chest Xray images,addressing the critical need for early detection in healthcare.A new comprehensive dataset was f... This paper presents a novelmulticlass systemdesigned to detect pleural effusion and pulmonary edema on chest Xray images,addressing the critical need for early detection in healthcare.A new comprehensive dataset was formed by combining 28,309 samples from the ChestX-ray14,PadChest,and CheXpert databases,with 10,287,6022,and 12,000 samples representing Pleural Effusion,Pulmonary Edema,and Normal cases,respectively.Consequently,the preprocessing step involves applying the Contrast Limited Adaptive Histogram Equalization(CLAHE)method to boost the local contrast of the X-ray samples,then resizing the images to 380×380 dimensions,followed by using the data augmentation technique.The classification task employs a deep learning model based on the EfficientNet-V1-B4 architecture and is trained using the AdamW optimizer.The proposed multiclass system achieved an accuracy(ACC)of 98.3%,recall of 98.3%,precision of 98.7%,and F1-score of 98.7%.Moreover,the robustness of the model was revealed by the Receiver Operating Characteristic(ROC)analysis,which demonstrated an Area Under the Curve(AUC)of 1.00 for edema and normal cases and 0.99 for effusion.The experimental results demonstrate the superiority of the proposedmulti-class system,which has the potential to assist clinicians in timely and accurate diagnosis,leading to improved patient outcomes.Notably,ablation-CAM visualization at the last convolutional layer portrayed further enhanced diagnostic capabilities with heat maps on X-ray images,which will aid clinicians in interpreting and localizing abnormalities more effectively. 展开更多
关键词 image classification decision support system EfficientNet-V1-B4 AdamW optimizer pulmonary edema pleural effusion chest X-rays
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基于4D-CT的三种呼吸门控技术对肺癌立体定向放射治疗计划靶区及正常组织器官体积、受照剂量的影响
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作者 管浩然 闫冰 +3 位作者 李骁扬 李迪迪 吴广军 吴齐兵 《陕西医学杂志》 CAS 2024年第7期926-930,共5页
目的:探讨基于4D-CT的三种呼吸门控技术对肺癌立体定向放射治疗(SBRT)计划靶区及正常组织器官体积、受照剂量的影响。方法:收集108例肺癌患者的病例资料,比较患者在基于4D-CT的三种呼吸门控技术下接受SBRT治疗的肿瘤靶区(GTV)、计划靶区... 目的:探讨基于4D-CT的三种呼吸门控技术对肺癌立体定向放射治疗(SBRT)计划靶区及正常组织器官体积、受照剂量的影响。方法:收集108例肺癌患者的病例资料,比较患者在基于4D-CT的三种呼吸门控技术下接受SBRT治疗的肿瘤靶区(GTV)、计划靶区(PTV)体积和受照剂量,并比较三种呼吸门控技术下正常组织的受照剂量。结果:三种不同技术下,患者GTV与PTV体积比较存在统计学意义差异(均P<0.05),其中自由呼吸(FB)技术下的GTV与PTV体积较主动呼吸控制(ABC)、呼吸门控(RG)技术下高,RG技术下GTV与PTV体积较ABC技术下高(均P<0.05);三种不同技术下PTV受照剂量参数靶区适形度指数(CI)水平差异无统计学意义(均P>0.05);三种不同技术下PTV受照剂量参数靶区剂量均匀性指数(HI)、GI水平差异有统计学意义(均P<0.05);其中FB技术下的GI较ABC技术和RG技术下低,HI水平较ABC技术和RG技术下高,ABC技术下的HI水平较RG技术下低(均P<0.05);三种不同技术下心脏、大血管、气管、食管以及脊髓的受照剂量比较差异无统计学意义(均P>0.05);三种不同技术下双肺V_(5)、V_(20)以及平均照射剂量(MLD)比较差异有统计学意义(均P<0.05);FB技术下的V_(5)、V_(20)以及MLD较ABC、RG技术下高,RG技术下V_(5)、V_(20)以及MLD较ABC技术下高(均P<0.05)。结论:基于4D-CT的ABC与RG技术相较于FB技术更有利于缩小靶区体积,提高治疗剂量,同时更有利于降低病灶危及器官与组织的受照剂量。 展开更多
关键词 4d-ct 呼吸门控技术 肺癌 立体定向放射治疗 计划靶区 受照剂量
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Geant4 simulation of fast-electron bremsstrahlung imaging at the HL-3 tokamak
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作者 Shi-Kui Cheng Yi-Po Zhang +4 位作者 Yue-Jiang Shi Jie Zhang Shuai Guan Hong-Bing Xu Qiu-Lei Yang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第9期213-229,共17页
To further research on high-parameter plasma,we plan to develop a two-dimensional hard X-ray(HXR)imaging system at the HL-3 tokamak to measure HXRs with energies ranging from 20 to 300 keV.The application of an array-... To further research on high-parameter plasma,we plan to develop a two-dimensional hard X-ray(HXR)imaging system at the HL-3 tokamak to measure HXRs with energies ranging from 20 to 300 keV.The application of an array-structured detector ensures that this system can measure HXR-radiation spectra from the entire plasma cross section.Therefore,it is suitable for the study of fast-electron physics,such as radio-frequency wave current drives,fast electrons driving instabilities,and plasma disruptions in fusion research.In this study,we develop a simulation for calculating fast-electron bremsstrahlung in the HL-3 tokamak based on the Monte Carlo simulation code Geant4,in which the plasma geometry and forward scattering of fast-electron bremsstrahlung are considered.The preliminary calculation results indicate that the HXR energy deposi-tion on the detector is symmetrically distributed,even though the plasma distribution is asymmetric owing to the toroidal effect.These simulation results are helpful in constructing the relationship between the energy deposition on the detector and parameter distribution on the plasma cross section during HL-3 experiments.This is beneficial for the reconstruction of the fast-electron-distribution function and for optimizing the design of the HXR-imaging system. 展开更多
关键词 GEANT4 SIMULATION HL-3 TOKAMAK Fast-electron bremsstrahlung Hard X-ray imaging
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Comparison of displacement damage effects on the dark signal in CMOS image sensors induced by CSNS back-n and XAPR neutrons
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作者 Yuan-Yuan Xue Zu-Jun Wang +3 位作者 Wu-Ying Ma Min-Bo Liu Bao-Ping He Shi-Long Gou 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期29-40,共12页
This study investigates the effects of displacement damage on the dark signal of a pinned photodiode CMOS image sensor(CIS)following irradiation with back-streaming white neutrons from white neutron sources at the Chi... This study investigates the effects of displacement damage on the dark signal of a pinned photodiode CMOS image sensor(CIS)following irradiation with back-streaming white neutrons from white neutron sources at the China spallation neutron source(CSNS)and Xi'an pulsed reactor(XAPR).The mean dark signal,dark signal non-uniformity(DSNU),dark signal distribution,and hot pixels of the CIS were compared between the CSNS back-n and XAPR neutron irradiations.The nonionizing energy loss and energy distribution of primary knock-on atoms in silicon,induced by neutrons,were calculated using the open-source package Geant4.An analysis combining experimental and simulation results showed a noticeable proportionality between the increase in the mean dark signal and the displacement damage dose(DDD).Additionally,neutron energies influence DSNU,dark signal distribution,and hot pixels.High neutron energies at the same DDD level may lead to pronounced dark signal non-uniformity and elevated hot pixel values. 展开更多
关键词 Displacement damage effects CMOS image sensor(CIS) CSNS back-n XAPR neutrons Geant4 Dark signal non-uniformity(DSNU)
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腹部呼吸幅度与基于4D-CT测量膈肌运动范围及肺体积变化量相关性研究
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作者 罗翊铭 陆显发 杨第炸 《中国科技期刊数据库 医药》 2024年第4期0076-0080,共5页
通过研究腹部呼吸幅度、膈肌运动范围和肺体积变化量之间的关系,为临床医生在勾画治疗靶区外扩范围提供参考。方法 选取24例肺癌患者,对每个患者的呼吸幅度、膈肌运动范围、肺部体积进行测量,采用SPSS25.0软件中的Pearsons双变量相关性... 通过研究腹部呼吸幅度、膈肌运动范围和肺体积变化量之间的关系,为临床医生在勾画治疗靶区外扩范围提供参考。方法 选取24例肺癌患者,对每个患者的呼吸幅度、膈肌运动范围、肺部体积进行测量,采用SPSS25.0软件中的Pearsons双变量相关性和独立样本t检验进行数据分析。结果 膈肌运动范围与肺体积变化量具有性相关且,右膈肌运动范围与右肺体积变化量呈显著性相关(P<0.05,r=0.9);左膈肌运动范围与左肺体积变化量呈中度相关(P<0.05,r=0.432)。相较于左膈肌,右膈肌运动范围较大,且个体差异性更大,右肺在呼吸周期中体积变化较左肺也偏大,呼吸幅度对双肺体积变化影响较小。结论 膈肌运动范围与肺体积变化量具有性相性,呼吸幅度与双肺体积变化量之间不具有统计学差异。 展开更多
关键词 腹部呼吸幅度 基于4d-ct测量膈肌 运动范围 肺体积变化量
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A cloud optical and microphysical property product for the advanced geosynchronous radiation imager onboard China's Fengyun-4 satellites: The first version 被引量:1
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作者 Chao Liu Yuxing Song +5 位作者 Ganning Zhou Shiwen Teng Bo Li Na Xu Feng Lu Peng Zhang 《Atmospheric and Oceanic Science Letters》 CSCD 2023年第3期52-57,共6页
风云四号作为中国新一代静止气象卫星,提供了高时空分辨率的监测产品。本文介绍风云四号搭载的先进地球同步轨道辐射成像仪AGRI的云光学和微物理特性产品.该产品包含了基于双光谱通道反演的云光学厚度和云粒子有效半径产品,以及基于机... 风云四号作为中国新一代静止气象卫星,提供了高时空分辨率的监测产品。本文介绍风云四号搭载的先进地球同步轨道辐射成像仪AGRI的云光学和微物理特性产品.该产品包含了基于双光谱通道反演的云光学厚度和云粒子有效半径产品,以及基于机器学习的云识别和云相态产品。与时空匹配的主动卫星观测结果对比显示,该产品的云识别和云相态的准确率分别在95%和85%;该产品提供的云光学厚度和云有效粒径与经典的MODIS产品的相关系数达到0.76和0.63.团队将持续优化和更新该云光学和微物理特性定量产品,服务风云四号卫星定量应用。 展开更多
关键词 风云四号 先进地球同步轨道辐射成像仪 云相态 云光学厚度 云有效粒子半径
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Four-Dimensional Computerized Tomography (4D-CT) Reconstruction Based on the Similarity Measure of Spatial Adjacent Images 被引量:9
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作者 ZHANG Shu-xu ZHOU Ling-hong +3 位作者 CHEN Guang-jie LIN Sheng-qu YE Yu-sheng ZHANG Hai-nan 《Chinese Journal of Biomedical Engineering(English Edition)》 2008年第3期106-113,共8页
Objective:To investigate the feasibility of a 4D-CT reconstruction method based on the similarity principle of spatial adjacent images and mutual information measure. Methods:A motor driven sinusoidal motion platform ... Objective:To investigate the feasibility of a 4D-CT reconstruction method based on the similarity principle of spatial adjacent images and mutual information measure. Methods:A motor driven sinusoidal motion platform made in house was used to create one-dimensional periodical motion that was along the longitudinal axis of the CT couch. The amplitude of sinusoidal motion was set to an amplitude of ±1 cm. The period of the motion was adjustable and set to 3.5 s. Phantom objects of two eggs were placed in a Styrofoam block, which in turn were placed on the motion platform. These objects were used to simulate volumes of interest undergoing ideal periodic motion. CT data of static phantom were acquired using a multi-slice general electric (GE) LightSpeed 16-slice CT scanner in an axial mode. And the CT data of periodical motion phantom were acquired in an axial and cine-mode scan. A software program was developed by using VC++ and VTK software tools to resort the CT data and reconstruct the 4D-CT. Then all of the CT data with same phase were sorted by the program into the same series based on the similarity principle of spatial adjacent images and mutual information measure among them, and 3D reconstruction of different phase CT data were completed by using the software. Results:All of the CT data were sorted accurately into different series based on the similarity principle of spatial adjacent images and mutual information measures among them. Compared with the unsorted CT data, the motion artifacts in the 3D reconstruction of sorted CT data were reduced significantly, and all of the sorted CT series result in a 4D-CT that reflected the characteristic of the periodical motion phantom. Conclusion:Time-resolved 4D-CT reconstruction can be implemented with any general multi-slice CT scanners based on the similarity principle of spatial adjacent images and mutual information measure.The process of the 4D-CT data acquisition and reconstruction were not restricted to the hardware or software of the CT scanner and has the feasibility ,which extensive applicability. 展开更多
关键词 PHANTOM four-dimensional computed tomography 4d-ct reconstruc-tion SIMILARITY motion artifacts mutual information
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Magnetic resonance imaging evaluation of head and neck involvement in IgG4-related disease
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作者 Umur Anil Pehlivan Kamil Karaali +8 位作者 Hatice Deniz Ilhan Mehmet Soy Didem Arslan Omer Kaya Rabia Miray Kisla-Ekinci Burcak Cakir-Pekoz Ummuhan Cay Arbil Acikalin Ahmet Muhtesem Agildere 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2023年第6期276-283,共8页
Objective:To evaluate the radiological features of IgG4-related disease(IgG4-RD)in the head and neck region.Methods:In this radiology-based study,radiological features,clinical,laboratory,pathological findings,and pro... Objective:To evaluate the radiological features of IgG4-related disease(IgG4-RD)in the head and neck region.Methods:In this radiology-based study,radiological features,clinical,laboratory,pathological findings,and prognosis of nine patients with head and neck involvement diagnosed with IgG4-RD were investigated retrospectively.Results:The median age of the patients was 38 years(range:2.5-79 years),and there were six males and three females.The most common symptoms and clinical findings of the patients were eyelid and lacrimal gland swelling,painless exophthalmos,and ophthalmoplegia.The most common site of involvement on MRI was the orbit.Orbital involvement was followed by branches of the trigeminal nerve,sinonasal cavity,cervical lymph nodes,and dural involvement.The most common and remarkable imaging features were T2 hypointensity and diffuse homogeneous contrast enhancement.Conclusions:Head and neck involvement of the IgG4-RD,has specific imaging features that can help with diagnosis.Thus,early diagnosis and better outcomes can be achieved with increasing awareness of these features of this relatively new pathology. 展开更多
关键词 IGG4 Head and neck imaging Magnetic resonance imaging ORBIT Perineural spreading
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Image Recognition Based on Deep Learning with Thermal Camera Sensing
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作者 Wen-Tsai Sung Chin-Hsuan Lin Sung-Jung Hsiao 《Computer Systems Science & Engineering》 SCIE EI 2023年第7期505-520,共16页
As the COVID-19 epidemic spread across the globe,people around the world were advised or mandated to wear masks in public places to prevent its spreading further.In some cases,not wearing a mask could result in a fine... As the COVID-19 epidemic spread across the globe,people around the world were advised or mandated to wear masks in public places to prevent its spreading further.In some cases,not wearing a mask could result in a fine.To monitor mask wearing,and to prevent the spread of future epidemics,this study proposes an image recognition system consisting of a camera,an infrared thermal array sensor,and a convolutional neural network trained in mask recognition.The infrared sensor monitors body temperature and displays the results in real-time on a liquid crystal display screen.The proposed system reduces the inefficiency of traditional object detection by providing training data according to the specific needs of the user and by applying You Only Look Once Version 4(YOLOv4)object detection technology,which experiments show has more efficient training parameters and a higher level of accuracy in object recognition.All datasets are uploaded to the cloud for storage using Google Colaboratory,saving human resources and achieving a high level of efficiency at a low cost. 展开更多
关键词 image recognition convolutional neural network YOLOv4 thermal camera sensing
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Simultaneous Morphologies and Luminescence Control of NaYF_(4)∶Yb/Er Nanophosphors by Surfactants for Cancer Cell Imaging
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作者 盛洋怡 程璐 +3 位作者 宋岳林 王兆洁 蒋伟忠 陈志钢 《Journal of Donghua University(English Edition)》 CAS 2023年第2期127-133,共7页
Hydrophilic rare-earth up-conversion nanophosphors(UCNPs)with small sizes and a strong up-conversion luminescence have attracted much interest.Herein the simultaneous control of morphologies and the up-conversion lumi... Hydrophilic rare-earth up-conversion nanophosphors(UCNPs)with small sizes and a strong up-conversion luminescence have attracted much interest.Herein the simultaneous control of morphologies and the up-conversion luminescence intensities was reported for NaYF_(4)∶Yb/Er nanophosphors by a facile hydrothermal procedure with different surfactants.With the change of the surfactants from polyvinylpyrrolidone(PVP)to sodium citrate(CIT),edetate disodium(EDTA)or sodium dodecyl benzenesulfonate(SDBS),the morphology of NaYF_(4)∶Yb/Er nanophosphors transformed from nanoparticles with a diameter of about 70.0 nm to hexagonal nanoblocks with a thickness of about 125.0 nm and a length of about 240.0 nm,nanorods with a diameter of about 700.0 nm and a length of about 2.6μm,or nanowires with a diameter of 250.0 nm and a length of about 3.2μm.Simultaneously,their up-conversion luminescence intensity went down gradually under laser irradiation at a wavelength of 980 nm due to the increase of photobleaching.PVP-capped NaYF_(4)∶Yb/Er nanoparticles exhibited the smallest size and the strongest up-conversion luminescence intensity.Biological experiment results revealed that NaYF_(4)∶Yb/Er nanophosphors exhibited a high biocompatibility and could be used as biological labels with a perfect signal-to-noise ratio for cancer cell imaging. 展开更多
关键词 NaYF_(4) NANOPHOSPHOR LUMINESCENCE surfactant adjustable morphology cancer cell imaging
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乳腺数字X射线联合MRI对Bi-RADS 4级可疑恶性微钙化患者的诊断价值
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作者 刘兆丰 金静强 马立岩 《中国医药导报》 CAS 2024年第18期156-158,163,共4页
目的探讨乳腺数字X射线联合磁共振成像(MRI)评估Bi-RADS 4级可疑恶性微钙化的诊断价值。方法选取2021年6月至2023年7月江苏省昆山市第二人民医院行手术治疗的79例乳腺Bi-RADS 4级可疑恶性微钙化患者为研究对象,所有患者均进行乳腺数字X... 目的探讨乳腺数字X射线联合磁共振成像(MRI)评估Bi-RADS 4级可疑恶性微钙化的诊断价值。方法选取2021年6月至2023年7月江苏省昆山市第二人民医院行手术治疗的79例乳腺Bi-RADS 4级可疑恶性微钙化患者为研究对象,所有患者均进行乳腺数字X射线、MRI检查。以病理结果为“金标准”,分析良性、恶性患者乳腺数字X射线图像特征、MRI特征,分析不同检查方法的诊断效能。结果以病理检查结果为“金标准”,恶性患者34例,良性患者45例,其中乳腺纤维腺瘤21例、乳腺囊性增生12例、乳腺炎12例。良、恶性患者乳腺微钙化、无定型、粗糙不均质分布比较,差异有统计学意义(P<0.05)。良、恶性患者时间-信号强度曲线各型占比比较,差异有统计学意义(P<0.05)。乳腺数字X射线联合MRI检查的特异度、准确度高于单一检测,差异有统计学意义(P<0.05)。乳腺数字X射线、MRI、乳腺数字X射线联合MRI检查与“金标准”一致性一般,Kappa值分别为0.625、0.630、0.726。结论乳腺数字X射线联合MRI检查诊断Bi-RADS 4级可疑恶性微钙化的价值较高,有助于临床医生准确地判断可疑微钙化患者的恶性可能性。 展开更多
关键词 乳腺数字X射线 磁共振成像 Bi-RADS 4 恶性 微钙化
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^(18)F-FDG-(OAc)_(4)的合成及其在小鼠体内的生物分布
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作者 何正中 庞丁华 +5 位作者 李宁 张实来 杨洪 蒙小飞 杨志 肖国有 《中国医疗设备》 2024年第5期26-30,共5页
目的分析正电子药物合成器合成基氟-18标记的四乙酰脱氧葡糖[1,3,4,6-四乙酰基-O-2-^(18)F-2-脱氧-β-D葡萄糖,简称^(18)F-FDG-(OAc)_(4)]的稳定性和实用性。方法基于合成器及其合成工艺流程,进行^(18)F-FDG-(OAc)4合成产量和质量控制... 目的分析正电子药物合成器合成基氟-18标记的四乙酰脱氧葡糖[1,3,4,6-四乙酰基-O-2-^(18)F-2-脱氧-β-D葡萄糖,简称^(18)F-FDG-(OAc)_(4)]的稳定性和实用性。方法基于合成器及其合成工艺流程,进行^(18)F-FDG-(OAc)4合成产量和质量控制及其与氟-18标记的脱氧葡萄糖(2-[18F]-氟-2-脱氧-D-葡萄糖,简称18F-FDG)在小鼠体内的生物分布异同分析。结果连续3批合成^(18)F-FDG-(OAc)4的成功率为100%,产率分别为59.64%、60.61%、59.72%,产品溶液为无色透明溶液,放射性化学纯度≥96%(Rf值为0.8~0.9),放射性核纯度为100%。^(18)F-FDG-(OAc)_(4)与18F-FDG注入小鼠,后各个脏器的放射性摄取均无差别,差异无统计学意义(P>0.05)。结论正电子药物合成器合成^(18)F-FDG-(OAc)4的流程简单、便捷,合成成功率和合成产率较高,具有较强的稳定性和实用性。 展开更多
关键词 ^(18)F-FDG-(OAc)_(4) 18F-FDG 显像剂制备 生物分布
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IMR算法与iDose^(4)算法对低剂量左房肺静脉CT图像质量影响的对比研究
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作者 杜国相 梁志梅 +3 位作者 李敏 罗瑛译 卢炳丰 李伟雄 《中国临床新医学》 2024年第10期1148-1152,共5页
目的比较全模型迭代重建(IMR)算法与混合迭代重建(iDose 4)算法对低剂量左房肺静脉CT图像质量的影响。方法招募2020年1月至12月因房颤于广西医科大学第二附属医院行射频消融术的患者30例,均接受低剂量左房肺静脉CT检查,管电压80 kV,管电... 目的比较全模型迭代重建(IMR)算法与混合迭代重建(iDose 4)算法对低剂量左房肺静脉CT图像质量的影响。方法招募2020年1月至12月因房颤于广西医科大学第二附属医院行射频消融术的患者30例,均接受低剂量左房肺静脉CT检查,管电压80 kV,管电流350 mA,扫描结束后采用IMR算法(IMR组)和iDose 4算法(iDose 4组)重建图像,对两组图像质量进行主观评分。于右上肺静脉(RSPV)、右下肺静脉(RIPV)、左上肺静脉(LSPV)、左下肺静脉(LIPV)开口处勾画感兴趣区(ROI),于左心房中心层面对左心房、降主动脉及胸壁脂肪勾画ROI。ROI选择密度均匀处勾画,记录各ROI内CT值和噪声值(SD值),计算左心房、RSPV、RIPV、LSPV、LIPV的对比噪声比(CNR)和信噪比(SNR),对比两组图像的客观评分。结果两名放射科医师对IMR组和iDose 4组图像的主观评价一致性高,组间相关系数(ICC)分别为0.895(P<0.001)、0.920(P<0.001)。IMR组图像质量主观评分显著高于iDose 4组[(4.50±0.57)分vs(3.86±0.68)分;t=3.898,P<0.001]。IMR组左心房、RSPV、RIPV、LSPV、LIPV的图像噪声值(SD值)低于iDose 4组,SNR和CNR高于iDose 4组,差异有统计学意义(P<0.05)。IMR组左心房、RSPV、RIPV、LSPV、LIPV的CT值低于iDose 4组,差异有统计学意义(P<0.05)。结论相较于iDose 4算法,IMR算法可显著降低低剂量左房肺静脉CT图像的噪声,提高SNR和CNR,从而提高图像质量,值得在临床中推广。 展开更多
关键词 左房肺静脉CT 全模型迭代重建算法 混合迭代重建算法 图像质量
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AD小鼠脑胶质淋巴系统CSF流入量与年龄的关系:基于9.4 T DCE-MRI的可视化研究
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作者 江心雨 苏云燕 +1 位作者 胡春洪 张龙江 《磁共振成像》 CAS CSCD 北大核心 2024年第4期113-119,共7页
目的基于9.4 T动态对比增强(dynamic contrast-enhanced,DCE)-MRI探索不同月龄的阿尔茨海默病(Alzheimer's disease,AD)模型小鼠脑胶质淋巴系统的脑脊液(cerebrospinal fluid,CSF)流入变化,以阐明随年龄增长脑胶质淋巴系统清除的变... 目的基于9.4 T动态对比增强(dynamic contrast-enhanced,DCE)-MRI探索不同月龄的阿尔茨海默病(Alzheimer's disease,AD)模型小鼠脑胶质淋巴系统的脑脊液(cerebrospinal fluid,CSF)流入变化,以阐明随年龄增长脑胶质淋巴系统清除的变化规律及水通道蛋白4(aquaporin4,AQP4)在脑胶质淋巴系统清除中的作用。材料与方法取2、4、6和8月龄的APP/PS1 AD小鼠和野生型(wild-type,WT)小鼠,每组1只,共8组,向小脑延髓池中注射钆喷酸葡胺(Gadopentetate dimeglumine,Gd-DTPA)后第30 min完成第一次DCE-MRI扫描,以后每15 min采集一次,共完成8次扫描。随后在DCE-MRI扫描之前,使用AQP4抑制剂N-(1,3,4-噻二唑基)烟酰胺[N-(1,3,4-Thiadiazolyl)nicotinamide,TGN-020]对2月龄WT小鼠进行处理。采用免疫荧光法检测AQP4和β-淀粉样蛋白随月龄增长的表达变化。结果在APP/PS1小鼠模型的疾病早期,观察到随月龄增加,淀粉样蛋白逐渐累积,CSF流入信号强度均值从增加到降低,其中4至6月龄小鼠淀粉样蛋白的累积速率缓慢,对应于相应月龄CSF流入信号强度均值最高(4月龄为2711.67±1270.25;6月龄为2632.25±729.65)。同时,AQP4表现出随月龄增加极化程度降低的变化过程。随后,经AQP4抑制剂TGN-020处理后,观察到脑胶质淋巴系统的CSF流入信号强度均值降低(由3578.08±1199.95下降为1655.42±377.96;P=0.06)。结论在AD疾病的早期阶段(8月龄前),6月龄的脑胶质淋巴系统利用更明显,此阶段可能作为AD治疗的窗口期。AQP4在脑胶质淋巴系统中起着重要作用,可能作为研究和治疗AD的靶点。 展开更多
关键词 脑胶质淋巴系统 阿尔茨海默病 9.4 T磁共振成像 动态对比增强磁共振成像 水通道蛋白4 APP/PS1小鼠
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声触诊组织成像对TI-RADS4类甲状腺实性结节鉴别诊断的价值研究 被引量:1
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作者 谢晓玮 罗玉洁 卓晓英 《影像技术》 CAS 2024年第1期39-44,共6页
目的:探讨声触诊组织成像技术(VTI)在鉴别TI-RADS4类甲状腺实性结节良恶性中的应用价值。方法:2020年10月-2021年10月,我院甲乳外科收治的92例患者105个经常规超声(conventional ultrasonography,CUS)诊断为TI-RADS4类的甲状腺结节。弹... 目的:探讨声触诊组织成像技术(VTI)在鉴别TI-RADS4类甲状腺实性结节良恶性中的应用价值。方法:2020年10月-2021年10月,我院甲乳外科收治的92例患者105个经常规超声(conventional ultrasonography,CUS)诊断为TI-RADS4类的甲状腺结节。弹性检查:行VTI成像,获取VTI弹性图,找出VTI面积比(AR)鉴别TI-RADS4类甲状腺实性结节良恶性的最佳截点,以病理诊断为金标准,分析CUS及VTI技术诊断TI-RADS4类甲状腺实性结节的灵敏度、特异度和准确度。结果:以AR=1.28作为诊断TI-RADS 4类甲状腺恶性结节的最佳截点,灵敏度为81.7%,特异度为92.1%,准确度为86.3%。结论:CUS联合VTI技术诊断TI-RADS4类甲状腺实性结节的准确度明显增高。 展开更多
关键词 声触诊组织成像 TI-RADS4 甲状腺实性结节
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MRI动态增强成像联合血清PCSK9、TM4SF1诊断乳腺癌的临床价值
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作者 韩晓凤 侯宗宾 +1 位作者 李小潘 梁仁杰 《中国CT和MRI杂志》 2024年第11期89-91,共3页
目的探讨磁共振成像(MRI)动态增强联合血清前蛋白转化酶枯草溶菌素9(PCSK9)、四跨膜蛋白超家族成员1(TM4SF1)诊断乳腺癌的临床价值。方法选取2020年2月至2022年6月本院收治的乳腺癌患者102例作为乳腺癌组,另选同期乳腺良性肿瘤患者102例... 目的探讨磁共振成像(MRI)动态增强联合血清前蛋白转化酶枯草溶菌素9(PCSK9)、四跨膜蛋白超家族成员1(TM4SF1)诊断乳腺癌的临床价值。方法选取2020年2月至2022年6月本院收治的乳腺癌患者102例作为乳腺癌组,另选同期乳腺良性肿瘤患者102例,作为对照组,两组患者均进行MRI动态增强成像检查;采用酶联免疫吸附法(ELISA)检测血清PCSK9、TM4SF1水平;受试者工作特征(ROC)曲线分析血清PCSK9、TM4SF1对乳腺癌的临界诊断点;采用四格表分析MRI动态增强成像联合血清PCSK9、TM4SF1对乳腺癌的诊断价值。结果乳腺癌病灶部位较良性组相比其癌旁组织分界不清,边缘表现不规则,强化不均匀。乳腺癌组血清PCSK9、TM4SF1水平显著高于良性组(P<0.05)。根据ROC曲线得知,血清PCSK9诊断乳腺癌的AUC为0.929,血清TM4SF1诊断乳腺癌的AUC为0.880,二者联合诊断乳腺癌的AUC为0.959。MRI动态增强成像在乳腺癌诊断中准确度为89.22%,灵敏度为84.31%,特异度为94.12%;PCSK9在乳腺癌诊断中准确度为84.31%,灵敏度为78.43%,特异度为90.20%;TM4SF1在乳腺癌诊断中准确度为83.82%,灵敏度为77.45%,特异度为90.20%;三者联合检测在乳腺癌诊断中准确度为90.24%,灵敏度为88.24%,特异度为92.23%。MRI动态增强成像、血清PCSK9、TM4SF1与肿瘤直径、TNM分期、淋巴结转移和分类风险有关(P<0.05)。结论乳腺癌血清PCSK9、TM4SF1水平均升高,MRI动态增强成像联合血清PCSK9、TM4SF1可提高乳腺癌的诊断价值。 展开更多
关键词 乳腺癌 磁共振成像动态增强扫描 前蛋白转化酶枯草溶菌素9 四跨膜蛋白超家族成员1 诊断
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Immunoglobulin G4-related spinal pachymeningitis:A case report
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作者 Tae-Seok Chae Da-Sol Kim +4 位作者 Gi-Wook Kim Yu Hui Won Myoung-Hwan Ko Sung-Hee Park Jeong-Hwan Seo 《World Journal of Clinical Cases》 SCIE 2024年第32期6551-6558,共8页
BACKGROUND Immunoglobulin G4-related disease(IgG4-RD)is a complex immune-mediated condition that causes fibrotic inflammation in several organs.A significant clinical feature of IgG4-RD is hypertrophic pachymeningitis... BACKGROUND Immunoglobulin G4-related disease(IgG4-RD)is a complex immune-mediated condition that causes fibrotic inflammation in several organs.A significant clinical feature of IgG4-RD is hypertrophic pachymeningitis,which manifests as inflammation of the dura mater in intracranial or spinal regions.Although IgG4-RD can affect multiple areas,the spine is a relatively rare site compared to the more frequent involvement of intracranial structures.CASE SUMMARY A 70-year-old male presented to our hospital with a two-day history of fever,altered mental status,and generalized weakness.The initial brain magnetic resonance imaging(MRI)revealed multiple small infarcts across various cerebral regions.On the second day after admission,a physical examination revealed motor weakness in both lower extremities and diminished sensation in the right lower extremity.Electromyographic evaluation revealed findings consistent with acute motor sensory neuropathy.Despite initial management with intravenous immunoglobulin for presumed Guillain-Barrésyndrome,the patient exhibited progressive worsening of motor deficits.On the 45th day of hospitalization,an enhanced MRI of the entire spine,focusing specifically on the thoracic 9 to lumbar 1 vertebral level,raised the suspicion of IgG4-related spinal pachymeningitis.Subsequently,the patient was administered oral prednisolone and participated in a comprehensive rehabilitation program that included gait training and lower extremity strengthening exercises.CONCLUSION IgG4-related spinal pachymeningitis,diagnosed on MRI,was treated with corticosteroids and a structured rehabilitation regimen,leading to significant improvement. 展开更多
关键词 Immunoglobulin G4 related disease Immunoglobulin G4 related spinal pachymeningitis Manual motor test ELECTROMYOGRAPHY Magnetic resonance imaging Case report
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Sonazoid超声造影在BI-RADS 4类乳腺结节诊疗中的应用价值研究
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作者 王瑞琦 马晓娟 段鹤立 《中国医学装备》 2024年第5期74-78,共5页
目的:探讨Sonazoid超声造影定性与定量分析在诊断乳腺影像报告和数据系统(BI-RADS)4类乳腺病变中的临床应用价值。方法:收集2022年4月至2023年4月于成都市第一人民医院行穿刺活检或手术的乳腺病变患者53例(53个病灶均为BI-RADS4类)。根... 目的:探讨Sonazoid超声造影定性与定量分析在诊断乳腺影像报告和数据系统(BI-RADS)4类乳腺病变中的临床应用价值。方法:收集2022年4月至2023年4月于成都市第一人民医院行穿刺活检或手术的乳腺病变患者53例(53个病灶均为BI-RADS4类)。根据乳腺结节病理结果将患者分为良性组(34例)和恶性组(19例)。所有患者在穿刺活检或者手术前均已行Sonazoid超声造影(CEUS)检查,比较良性组和恶性组乳腺结节造影定性与定量指标之间的差异,选取具有统计学差异的指标纳入回归方程,分别绘制受试者工作特征(ROC)曲线,获得ROC曲线下面积(AUC)。使用Sonoliver软件将造影时乳腺结节与周围正常组织的增强强度差异编码成直观的彩色图像,生成动态血管模型(DVP)参数图,分析在乳腺良、恶性结节中图像颜色的差异。结果:乳腺结节的Sonazoid超声造影定性指标观察中,恶性组乳腺结节多表现为增强范围扩大[13例(占68.4%)],不均匀增强[14例(占73.7%)],周围有穿支血流[12例(占63.2%)],与良性组比较差异均有统计学意义(x^(2)=10.268、9.642、5.717,P<0.05);乳腺结节的Sonazoid超声造影定量指标观察中,恶性组乳腺结节造影的上升时间(RT)、平均渡越时间(m TT)时长小于良性组,差异有统计学意义(Z=-1.985、-2.272,P<0.05)。将上述指标纳入多因素分析,分别建立定性、定量指标预测恶性结节的回归方程,定性、定量分析的ROC曲线下面积分别为0.723、0.902,定性分析结果优于定量分析,差异有统计学意义(Z=-1.965,P<0.05)。在DVP参数图像中,良性组34例结节中有23例(占67.6%)结节表现为病灶,感兴趣区域(ROI)内大部分呈较单调的红、黄色填充;恶性组19例中有15例(占78.9%)结节的ROI内呈紊乱不规则分散或团块状的斑片状红黄色填充。结论:Sonazoid超声造影能够鉴别乳腺BI-RADS 4类结节的良恶性,定性指标的诊断效能优于定量指标。 展开更多
关键词 乳腺病变 示卓安(Sonazoid)造影剂 超声造影(CEUS) 乳腺影像报告和数据系统(BI-RADS)4
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A low-power high-quality CMOS image sensor using 1.5 V 4T pinned photodiode and dual-CDS column-parallel single-slope ADC
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作者 Wenjing Xu Jie Chen +3 位作者 Zhangqu Kuang Li Zhou Ming Chen Chengbin Zhang 《Journal of Semiconductors》 EI CAS CSCD 2022年第8期53-59,共7页
This paper presents a low-power high-quality CMOS image sensor(CIS)using 1.5 V 4T pinned photodiode(4T-PPD)and dual correlated double sampling(dual-CDS)column-parallel single-slope ADC.A five-finger shaped pixel layer... This paper presents a low-power high-quality CMOS image sensor(CIS)using 1.5 V 4T pinned photodiode(4T-PPD)and dual correlated double sampling(dual-CDS)column-parallel single-slope ADC.A five-finger shaped pixel layer is proposed to solve image lag caused by low-voltage 4T-PPD.Dual-CDS is used to reduce random noise and the nonuniformity between columns.Dual-mode counting method is proposed to improve circuit robustness.A prototype sensor was fabricated using a 0.11μm CMOS process.Measurement results show that the lag of the five-finger shaped pixel is reduced by 80%compared with the conventional rectangular pixel,the chip power consumption is only 36 mW,the dynamic range is 67.3 dB,the random noise is only 1.55 e^(-)_(rms),and the figure-of-merit is only 1.98 e^(-)·nJ,thus realizing low-power and high-quality imaging. 展开更多
关键词 CMOS image sensor 4T pinned photodiode single-slope ADC correlated double sample counting method
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水通道蛋白4抗体阴性视神经炎临床与磁共振影像研究
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作者 温延斌 郭年波 +2 位作者 栾丽娟 刘平兰 刘其生 《上海医药》 CAS 2024年第17期73-76,共4页
目的:通过水通道蛋白4(AQP4)抗体阴性视神经炎临床与磁共振影像研究,探讨影响视神经的独立危险因素。方法:回顾性分析我院50例AQP4抗体阴性视神经炎患者的临床资料。结果:在基线水平上及治疗后的随访终点发现50例患者中分别有85、26只... 目的:通过水通道蛋白4(AQP4)抗体阴性视神经炎临床与磁共振影像研究,探讨影响视神经的独立危险因素。方法:回顾性分析我院50例AQP4抗体阴性视神经炎患者的临床资料。结果:在基线水平上及治疗后的随访终点发现50例患者中分别有85、26只眼睛的最佳矫正视力低于0.1;急性期视神经炎患者核磁共振成像(MRI)有36例出现多节段受累;多元逐步回归分析发现,基线视力水平、视神经受累节段数量是影响视神经的独立危险因素(P<0.05);分析随访资料发现,单相病程、疾病复发、转变为视神经脊髓炎谱系疾病分别为40例、9例、1例。结论:AQP4抗体阴性视神经炎病发率较高,预后视功能较差;易复发,但不易转变为视神经脊髓炎谱系疾病。 展开更多
关键词 视神经炎 水通道蛋白4 抗体 临床资料 磁共振影像
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