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Clinical application of improved 2D computer-assisted fluoroscopic navigation through simulating a 3D vertebrae image to guide pedicle screw internal fixation
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作者 刘恩志 《外科研究与新技术》 2011年第2期94-94,共1页
Objective To study the effect of using improved 2D computer-assisted fluoroscopic navigation through simulating 3D vertebrae image to guide pedicle screw internal fixation.Methods Posterior pedicle screw internal fixa... Objective To study the effect of using improved 2D computer-assisted fluoroscopic navigation through simulating 3D vertebrae image to guide pedicle screw internal fixation.Methods Posterior pedicle screw internal fixation,distraction 展开更多
关键词 Clinical application of improved 2D computer-assisted fluoroscopic navigation through simulating a 3D vertebrae image to guide pedicle screw internal fixation
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A comparative study of the morphometry of sperm head components in cattle, sheep, and pigs with a computer-assisted fluorescence method 被引量:1
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作者 Jesus L Yaniz Sara Capistros +2 位作者 Sandra Vicente-Fiel Carlos O Hidalgo Pilar Santolaria 《Asian Journal of Andrology》 SCIE CAS CSCD 2016年第6期840-843,共4页
The aim of this study was to compare the sperm nuclear and acrosomal morphometry of three species of domestic artiodactyls; cattle (Bos taurus), sheep (Ovis aries), and pigs (Sus scrofa). Semen smears of twenty ... The aim of this study was to compare the sperm nuclear and acrosomal morphometry of three species of domestic artiodactyls; cattle (Bos taurus), sheep (Ovis aries), and pigs (Sus scrofa). Semen smears of twenty ejaculates from each species were fixed and labeled with a propidium iodide-Pisum sativum agglutinin (PI/PSA) combination. Digital images of the sperm nucleus, acrosome, and whole sperm head were captured and analyzed. The use of the PI/PSA combination and CASA-Morph fluorescence-based method allowed the capture, morphometric analysis, and differentiation of most sperm nuclei, acrosomes and whole heads, and the assessment of acrosomal integrity with a high precision in the three species studied. For the size of the head and nuclear area, the relationship between the three species may be summarized as bull 〉 ram 〉 boar. However, for the other morphometric parameters (length, width, and perimeter), there were differences in the relationships between species for sperm nuclei and whole sperm heads. Bull sperm acrosomes were clearly smaller than those in the other species studied and covered a smaller proportion of the sperm head. The acrosomal morphology, small in the bull, large and broad in the sheep, and large, long, and with a pronounced equatorial segment curve in the boar, was species-characteristic. It was concluded that there are clear variations in the size and shape of the sperm head components between the three species studied, the acrosome being the structure showing the most variability, allowing a clear distinction of the spermatozoa of each species. 展开更多
关键词 ARTIODACTYLS computer-assisted sperm morphometry analysis fluorescence microscopy image analysis sperm morphometry
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Artificial intelligence-based diagnosis of hallux valgus interphalangeus using anteroposterior foot radiographs
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作者 Konrad Kwolek Artur Gadek +3 位作者 Kamil Kwolek Agnieszka Lechowska-Liszka Michal Malczak Henryk Liszka 《World Journal of Orthopedics》 2025年第6期86-98,共13页
BACKGROUND A recently developed method enables automated measurement of the hallux valgus angle(HVA)and the first intermetatarsal angle(IMA)from weightbearing foot radiographs.This approach employs bone segmentation t... BACKGROUND A recently developed method enables automated measurement of the hallux valgus angle(HVA)and the first intermetatarsal angle(IMA)from weightbearing foot radiographs.This approach employs bone segmentation to identify anatomical landmarks and provides standardized angle measurements based on established guidelines.While effective for HVA and IMA,preoperative radiograph analysis remains complex and requires additional measurements,such as the hallux interphalangeal angle(IPA),which has received limited research attention.AIM To expand the previous method,which measured HVA and IMA,by incorporating the automatic measurement of IPA,evaluating its accuracy and clinical relevance.METHODS A preexisting database of manually labeled foot radiographs was used to train a U-Net neural network for segmenting bones and identifying landmarks necessary for IPA measurement.Of the 265 radiographs in the dataset,161 were selected for training and 20 for validation.The U-Net neural network achieves a high mean Sørensen-Dice index(>0.97).The remaining 84 radiographs were used to assess the reliability of automated IPA measurements against those taken manually by two orthopedic surgeons(OA and OB)using computer-based tools.Each measurement was repeated to assess intraobserver(OA1 and OA2)and interobserver(O_(A2) and O_(B))reliability.Agreement between automated and manual methods was evaluated using the Intraclass Correlation Coefficient(ICC),and Bland-Altman analysis identified systematic differences.Standard error of measurement(SEM)and Pearson correlation coefficients quantified precision and linearity,and measurement times were recorded to evaluate efficiency.RESULTS The artificial intelligence(AI)-based system demonstrated excellent reliability,with ICC3.1 values of 0.92(AI vs OA2)and 0.88(AI vs O_(B)),both statistically significant(P<0.001).For manual measurements,ICC values were 0.95(OA2 vs OA1)and 0.95(OA2 vs OB),supporting both intraobserver and interobserver reliability.Bland-Altman analysis revealed minimal biases of:(1)1.61°(AI vs O_(A2));and(2)2.54°(AI vs O_(B)),with clinically acceptable limits of agreement.The AI system also showed high precision,as evidenced by low SEM values:(1)1.22°(O_(A2) vs O_(B));(2)1.77°(AI vs O_(A2));and(3)2.09°(AI vs O_(B)).Furthermore,Pearson correlation coefficients confirmed strong linear relationships between automated and manual measurements,with r=0.85(AI vs O_(A2))and r=0.90(AI vs O_(B)).The AI method significantly improved efficiency,completing all 84 measurements 8 times faster than manual methods,reducing the time required from an average 36 minutes to just 4.5 minutes.CONCLUSION The proposed AI-assisted IPA measurement method shows strong clinical potential,effectively corresponding with manual measurements.Integrating IPA with HVA and IMA assessments provides a comprehensive tool for automated forefoot deformity analysis,supporting hallux valgus severity classification and preoperative planning,while offering substantial time savings in high-volume clinical settings. 展开更多
关键词 computer-assisted Diagnosis Artificial Intelligence in Orthopedics Hallux Valgus Foot Deformities Acquired Machine Learning Diagnostic imaging computer-assisted image Interpretation
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Extravasated contrast volumetric assessment on computed tomography angiography in gastrointestinal bleeding:A useful predictor of positive angiographic findings
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作者 Laura Maria Cacioppa Chiara Floridi +11 位作者 Alessandra Bruno NicolòRossini Tommaso Valeri Alessandra Borgheresi Riccardo Inchingolo Francesco Cortese Giacomo Novelli Alessandro Felicioli Mario Torresi Pietro Boscarato Letizia Ottaviani Andrea Giovagnoni 《World Journal of Radiology》 2024年第5期115-127,共13页
BACKGROUND Gastrointestinal bleeding(GIB)is a severe and potentially life-threatening condition,especially in cases of delayed treatment.Computed tomography angiography(CTA)plays a pivotal role in the early identifica... BACKGROUND Gastrointestinal bleeding(GIB)is a severe and potentially life-threatening condition,especially in cases of delayed treatment.Computed tomography angiography(CTA)plays a pivotal role in the early identification of upper and lower GIB and in the prompt treatment of the haemorrhage.AIM To determine whether a volumetric estimation of the extravasated contrast at CTA in GIB may be a predictor of subsequent positive angiographic findings.METHODS In this retrospective single-centre study,35 patients(22 men;median age 69 years;range 16-92 years)admitted to our institution for active GIB detected at CTA and further submitted to catheter angiography between January 2018 and February 2022 were enrolled.Twenty-three(65.7%)patients underwent endoscopy before CTA.Bleeding volumetry was evaluated in both arterial and venous phases via a semi-automated dedicated software.Bleeding rate was obtained from volume change between the two phases and standardised for unit time.Patients were divided into two groups,according to the angiographic signs and their concordance with CTA.RESULTS Upper bleeding accounted for 42.9%and lower GIB for 57.1%.Mean haemoglobin value at the admission was 7.7 g/dL.A concordance between positive CTA and direct angiographic bleeding signs was found in 19(54.3%)cases.Despite no significant differences in terms of bleeding volume in the arterial phase(0.55 mL vs 0.33 mL,P=0.35),a statistically significant volume increase in the venous phase was identified in the group of patients with positive angiography(2.06 mL vs 0.9 mL,P=0.02).In the latter patient group,a significant increase in bleeding rate was also detected(2.18 mL/min vs 0.19 mL/min,P=0.02).CONCLUSION In GIB of any origin,extravasated contrast volumetric analysis at CTA could be a predictor of positive angiography and may help in avoiding further unnecessary procedures. 展开更多
关键词 Gastrointestinal haemorrhage Computed tomography angiography Volumetric analysis computer-assisted image interpretation Therapeutic embolization Transcatheter arterial embolization
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滤波反投影法和OSEM重建图像测量心功能参数的比较 被引量:5
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作者 李家俊 田月琴 何作祥 《中华核医学杂志》 CAS CSCD 北大核心 2011年第3期183-186,共4页
目的比较静息门控心肌显像滤波反投影法(FBP)和OSEM重建图像后用定量门控心肌断层显像(QGS)、四维模型心肌断层显像(4D—MSPECT)、爱莫瑞心脏工具箱(ECToolbox)软件测量的心功能参数。方法临床疑诊或确诊冠心病患者144例,均行^... 目的比较静息门控心肌显像滤波反投影法(FBP)和OSEM重建图像后用定量门控心肌断层显像(QGS)、四维模型心肌断层显像(4D—MSPECT)、爱莫瑞心脏工具箱(ECToolbox)软件测量的心功能参数。方法临床疑诊或确诊冠心病患者144例,均行^99Tc^m-MIBI静息门控心肌SPECT显像,所有患者均用FBP和OSEM重建图像,用QGS、4D—MSPECT、ECToolbox软件计算心功能参数LVEF,EDV和ESV,采用Bland—Altman法检验2种重建方法的一致性,配对t检验方法检验心功能参数差异,相关性分析用直线回归分析。结果FBP和OSEM重建测量的心功能参数一致性和相关性好(r均〉0.93,P均〈0.001)。QGS软件FBP重建测得的EDV低于OSEM重建测得的EDV,其他2种软件为FBP高于OSEM[QGS:(82.2±39.1)ml和(83.5±40.8)ml,t=-2.53,P〈0.05;4D—MSPECT:(93.5±46.9)ml和(88.8±45.2)ml,t=5.95,P〈0.01;ECToolbox:(106.4±51.1)ml和(100.8±49.0)ml,t=3.99,P〈0.01]。对于ESV,4D-MSPECT软件FBP测量值高于OSEM[(37.5±41.4)ml和(34.8±37.6)ml,t=3.92,P〈0.01]。QGS软件FBP测得的LVEF低于OSEM测得的LVEF[(62.1±16.9)%和(63.1±16.1)%,t=-3.14,P〈0.01]。ECToolbox软件FBP测得的LVEF高于用OSEM测得的LVEF[(74.1±18.8)%和(71.3±17.1)%,t=5.28,P〈0.01]。结论2种重建方法所测量的心功能参数虽然相关性和一致性很好,但某些参数值差异有统计学意义。 展开更多
关键词 冠状动脉疾病 体层摄影术 发射型计算机 单光子 图像处理 计算机辅助 MIBI
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人脸三维测量中的立体视觉 被引量:1
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作者 邓雁萍 李保洲 刘志敏 《上海交通大学学报》 EI CAS CSCD 北大核心 1998年第9期97-99,共3页
探讨了立体视觉在人脸外形测量中的应用,针对牙齿整容手术模拟时必须测量面部皮肤表面一些指定点三维信息的问题,建立了一种双目成象系统.根据人脸的特征,提出了人机交互确定特征点并结合先验知识进行图象匹配的新方法,通过受试者... 探讨了立体视觉在人脸外形测量中的应用,针对牙齿整容手术模拟时必须测量面部皮肤表面一些指定点三维信息的问题,建立了一种双目成象系统.根据人脸的特征,提出了人机交互确定特征点并结合先验知识进行图象匹配的新方法,通过受试者的正面和左右90°侧面三组图象、成象系统的全局坐标系与面部局部坐标系之间的几何位置,确定指定点在面部局部坐标系中的坐标值.误差校正项的引入有效地提高了系统的精度,实验结果表明了该系统的合理性. 展开更多
关键词 医学图象处理 立体视觉 人脸外形测量 图象匹配
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脑动脉瘤的MRI、MRA诊断 被引量:1
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作者 赵英 戴敏方 +1 位作者 赵新湘 沈永安 《医学影像学杂志》 2004年第5期344-347,共4页
目的 :探讨常规MRI、MRA以及不同后处理方法对脑动脉瘤的显示能力及诊断价值。方法 :应用磁共振T1、T2 WI以及 3D TOF MRA对 4 4例患者进行检查 ,并使用最大信号强度投影 (MIP)、表面遮盖成像 (SSD)、多平面重建 (MPR)、容积重建 (VR)... 目的 :探讨常规MRI、MRA以及不同后处理方法对脑动脉瘤的显示能力及诊断价值。方法 :应用磁共振T1、T2 WI以及 3D TOF MRA对 4 4例患者进行检查 ,并使用最大信号强度投影 (MIP)、表面遮盖成像 (SSD)、多平面重建 (MPR)、容积重建 (VR)等方法进行后处理。结果 :4 4例患者MRI均发现单发病灶 ,呈类圆形、梭形、不规则形、葫芦状等 ,边界清楚。病灶较特异的信号表现为 ,流空低信号、涡流信号 (混杂信号 )及部分病灶周围的血流伪影。MRA可清晰显示动脉瘤部位、形态、大小 ,选择适当后处理方法显示瘤体生长方向、瘤颈形态以及与载瘤血管的关系 ,为外科手术治疗提供依据。结论 :MRI、MRA为无创性显示脑血管的有效方法 ,提高对脑动脉瘤常规MRI、MRA典型征象的认识 ,熟练掌握并灵活运用MRA后处理方法可以有效提高磁共振对脑动脉瘤的诊断率。 展开更多
关键词 脑动脉瘤 磁共振成像 后处理方法
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Cholesterol crystal binding of biliary immunoglobulin A: visualization by fluorescence light microscopy 被引量:6
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作者 Frank Lammert Stefan Südfeld +1 位作者 Norbert Busch Siegfried Matern 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第2期198-202,共5页
AIM: To assess potential contributions of biliary IgA for crystal agglomeration into gallstones, we visualized cholesterol crystal binding of biliary IgA. METHODS: Crystal binding biliary proteins were extracted from ... AIM: To assess potential contributions of biliary IgA for crystal agglomeration into gallstones, we visualized cholesterol crystal binding of biliary IgA. METHODS: Crystal binding biliary proteins were extracted from human gallbladder bile using lectin affinity chromatography.Biliary IgA was isolated from the bound protein fraction by immunoaffinity chromatography. Pure cholesterol monohydrate crystals were incubated with biliary IgA and fluoresceine isothiocyanate (FITC)conjugated anti IgA at 37 degree. Samples were examined under polarizing and fluorescence light microscopy with digital image processing. RESULTS: Binding of biliary IgA to cholesterol monohydrate crystals could be visualized with FITC conjugated anti IgA antibodies.Peak fluorescence occurred at crystal edges and dislocations. Controls without biliary IgA or with biliary IgG showed no significant fluorescence. CONCLUSION: Fluorescence light microscopy provided evidence for cholesterol crystal binding of biliary IgA. Cholesterol crystal binding proteins like IgA might be important mediators of crystal agglomeration and growth of cholesterol gallstones by modifying the evolving crystal structures in vivo. 展开更多
关键词 Crystallization Bile CHOLELITHIASIS CHOLESTEROL Chromatography Affinity Fluorescent Antibody Technique Humans image Processing computer-assisted Immunoglobulin A Secretory Microscopy Fluorescence Research Support Non-U.S. Gov't
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Morphometric study on Leydig cells in capsulotomized testis of rats 被引量:1
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作者 QinDN LungMA 《Asian Journal of Andrology》 SCIE CAS CSCD 2002年第1期49-53,共5页
AIM: To further clarify the changes occurred in the testicular capsulotomized rats. METHODS: In testicular capsulotomized and sham-operated rats, the cross sectional area, the nucleus diameter and the number of Leydig... AIM: To further clarify the changes occurred in the testicular capsulotomized rats. METHODS: In testicular capsulotomized and sham-operated rats, the cross sectional area, the nucleus diameter and the number of Leydig cells were morphologically analyzed by the Vidas Image Processing System connected to a microscope. RESULTS: In the capsulotomized animals, the cross sectional area of Leydig cells was gradually increased from 30 days onwards. There was no obvious change in the nucleus diameter of Leydig cells. However, The Leydig cell number was significantly increased from day 30 onwards. CONCLUSION: In rats, testicular capsulotomy may induce hyperplasia/hypertrophy of Leydig cells in the testis. 展开更多
关键词 ANIMALS Cell Count Cell Nucleus image Processing computer-assisted Leydig Cells Male RATS Rats Sprague-Dawley TESTIS
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鼻内镜下数码照相机豚鼠中耳成像技术
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作者 徐志华 王继群 +2 位作者 贾海英 孙瑾 山艳春 《中国耳鼻咽喉头颈外科》 北大核心 2008年第5期315-316,共2页
耳鼻咽喉解剖结构复杂且部位隐蔽,较难直接视及,随着鼻内镜及数字图像采集装置广泛应用,极大促进了本专业的发展。在临床科研工作中常会遇到一些认为有必要保存下来的病例影像资料,由于各种原因导致缺乏数字图像采集装置,使许多病... 耳鼻咽喉解剖结构复杂且部位隐蔽,较难直接视及,随着鼻内镜及数字图像采集装置广泛应用,极大促进了本专业的发展。在临床科研工作中常会遇到一些认为有必要保存下来的病例影像资料,由于各种原因导致缺乏数字图像采集装置,使许多病例资料无法保留,且数字图像采集装置受采集芯片的限制,采集的图像像素相对较低。本研究旨在探索鼻内镜下利用普通数码相机拍摄清晰图像的方法,应用数码相机镜头直接接触内镜目镜,将所观察的图像拍摄下来,取得了良好的效果。 展开更多
关键词 内窥镜(Endoscopes) 豚鼠(Guinea Pigs) 中耳(Ear Middle) 图像处理 计算机辅助(image Processing computer-assisted)
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重建平面位移场的约束与余场补偿迭代算法
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作者 衡伟 《数据采集与处理》 CSCD 1995年第3期250-254,共5页
讨论由物体边界位移的测试值作为投影值来重建物体内部应变分量的双重迭代代数方法。该方法将图象重建理论应用于力学之中,用以变形协调方程作为约束条件求解位移场几何方程组的迭代过程作为内层迭代,并用其结果的投影值余场来逐次修... 讨论由物体边界位移的测试值作为投影值来重建物体内部应变分量的双重迭代代数方法。该方法将图象重建理论应用于力学之中,用以变形协调方程作为约束条件求解位移场几何方程组的迭代过程作为内层迭代,并用其结果的投影值余场来逐次修正的方法作为外层迭代,使重建算法的收敛速度及精度大为提高,尤其利于消除待重建的应变场各分量之间数据不一致所产生的影响。 展开更多
关键词 位移度测量 代数法 约束迭代法 余场法 激光测试
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基于图像处理技术的房屋裂缝宽度变化实时监测研究
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作者 杨钢 吴建超 +2 位作者 乔岳强 胡庆 汤勇 《四川建筑科学研究》 2018年第4期13-18,共6页
基于MATLAB数字图像处理技术,对房屋裂缝宽度变化进行实时监测,依次对采集裂缝图像进行灰度化、图像滤波、二值化、目标区域分割标记和像素标定等处理,计算获得图像裂缝最大宽度值及单次变化值、人工标志间距离变化值。通过与实测数据相... 基于MATLAB数字图像处理技术,对房屋裂缝宽度变化进行实时监测,依次对采集裂缝图像进行灰度化、图像滤波、二值化、目标区域分割标记和像素标定等处理,计算获得图像裂缝最大宽度值及单次变化值、人工标志间距离变化值。通过与实测数据相比,运用本文提出的计算方法获得房屋裂缝检测数据的识别精度为99.19%。利用MATLAB图像处理技术获得人工标志间距离变化值与最大裂缝宽度变化值累计相对误差为0.16%,人工标志间距离变化能够反映裂缝宽度变化情况。对于实际情况中无法寻找裂缝最大宽度处,而进行裂缝宽度变化实时监测时,可用人工标志间距离变化反映裂缝宽度变化情况。 展开更多
关键词 房屋裂缝 图像处理 裂缝宽度 实时监测 MATLAB
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用计算机仿真技术研究烟尘对图像的影响
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作者 武英 《南京晓庄学院学报》 2001年第4期38-41,共4页
文中讨论了不良天气条件对于成像产生的影响 ,着重探讨了烟尘即霾气溶胶粒子对图像的衰减作用 ,由晴天图像生成了受烟尘影响的图像。仿真软件由MATLAB语言编写 ,操作简单明了。
关键词 烟尘 衰减 仿真 图像处理
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3-Dimensional liver volume assessment in patients with hepatitis B virus-related liver cirrhosis during long-term oral nucleos(t)ide analogues therapy 被引量:6
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作者 Chang Hun Lee In Hee Kim +8 位作者 Jin Chang Moon Seung Young Seo Seong Hun Kim Sang Wook Kim Seung Ok Lee Soo Teik Lee Dae Ghon Kim Jae Do Yang Hee Chul Yu 《World Journal of Gastroenterology》 SCIE CAS 2017年第2期297-305,共9页
AIMTo assess the effect of long-term oral nucleos(t)ide analogues (NUCs) therapy on liver volume change in patients with suppress hepatitis B virus (HBV)-related liver cirrhosis.METHODSWe reviewed the data of na&#... AIMTo assess the effect of long-term oral nucleos(t)ide analogues (NUCs) therapy on liver volume change in patients with suppress hepatitis B virus (HBV)-related liver cirrhosis.METHODSWe reviewed the data of na&#x000ef;ve patients with HBV-related liver cirrhosis, who had taken oral NUCs therapy, between 2003 and 2007 at Chonbuk University Hospital. We analyzed two consecutive sets of abdominal computerized tomography scans-one at the time of treatment initiation and another at the second-year follow-up. Liver volume was calculated by 3-dimensional liver extraction volumetry program.RESULTSA total of 55 patients (34 males) were included. There was 114.3 mL &#x000b1; 167.8 mL (12.9% &#x000b1; 17.9%) of increase in liver volume during the two years of NUCs therapy (993.8 mL &#x000b1; 242.8 mL at baseline vs 1108.1 mL &#x000b1; 263.3 mL at two-year follow-up, P &#x0003c; 0.001). The ratio of the measured baseline liver volume to the estimated standard liver volume was improved from 70.8% to 78.0%. An increase in liver volume was shown not only in patients with compensated cirrhosis (P = 0.046) but also in those with decompensated cirrhosis (P &#x0003c; 0.001). Significant factors for volume increases were Child-Turcotte-Pugh grade and model for end-stage liver disease score improvement without virological breakthrough. In multiple linear regression analysis, delta albumin and delta alanine aminotransferase levels showed a significant association with the increase in liver volume (P = 0.002 and 0.005, respectively).CONCLUSIONLong-term oral NUCs therapy in patients with HBV-related liver cirrhosis lead to significant increase in liver volume assessed with 3-dimensional liver extraction volumetry program. 展开更多
关键词 Antiviral agents Liver cirrhosis Liver regeneration image processing computer-assisted
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Advances in deep learning for computed tomography denoising 被引量:5
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作者 Sung Bin Park 《World Journal of Clinical Cases》 SCIE 2021年第26期7614-7619,共6页
Computed tomography(CT)has seen a rapid increase in use in recent years.Radiation from CT accounts for a significant proportion of total medical radiation.However,given the known harmful impact of radiation exposure t... Computed tomography(CT)has seen a rapid increase in use in recent years.Radiation from CT accounts for a significant proportion of total medical radiation.However,given the known harmful impact of radiation exposure to the human body,the excessive use of CT in medical environments raises concerns.Concerns over increasing CT use and its associated radiation burden have prompted efforts to reduce radiation dose during the procedure.Therefore,low-dose CT has attracted major attention in the radiology,since CT-associated x-ray radiation carries health risks for patients.The reduction of the CT radiation dose,however,compromises the signal-to-noise ratio,which affects image quality and diagnostic performance.Therefore,several denoising methods have been developed and applied to image processing technologies with the goal of reducing image noise.Recently,deep learning applications that improve image quality by reducing the noise and artifacts have become commercially available for diagnostic imaging.Deep learning image reconstruction shows great potential as an advanced reconstruction method to improve the quality of clinical CT images.These improvements can provide significant benefit to patients regardless of their disease,and further advances are expected in the near future. 展开更多
关键词 DENOISING Deep learning computer-assisted imaging processing Iterative reconstruction Radiation dose
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Reproducibility of thrombus volume quantification in multicenter computed tomography pulmonary angiography studies 被引量:4
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作者 Audrey E Kaufman Alison N Pruzan +7 位作者 Ching Hsu Sarayu Ramachandran Adam Jacobi Indravadan Patel Lee Schwocho Michele F Mercuri Zahi A Fayad Venkatesh Mani 《World Journal of Radiology》 CAS 2018年第10期124-134,共11页
AIM To evaluate reproducibility of pulmonary embolism(PE) clot volume quantification using computed tomography pulmonary angiogram(CTPA) in a multicenter setting.METHODS This study was performed using anonymized data ... AIM To evaluate reproducibility of pulmonary embolism(PE) clot volume quantification using computed tomography pulmonary angiogram(CTPA) in a multicenter setting.METHODS This study was performed using anonymized data in conformance with HIPAA and IRB Regulations(March 2015-November 2016). Anonymized CTPA data was acquired from 23 scanners from 18 imaging centers using each site's standard PE protocol. Two independent analysts measured PE volumes using a semi-automated region-growing algorithm on an FDA-approved image analysis platform. Total thrombus volume(TTV) was calculated per patient as the primary endpoint. Secondary endpoints were individual thrombus volume(ITV), Qanadli score and modified Qanadli score per patient. Inter-and intra-observer reproducibility were assessed using intra-class correlation coefficient(ICC) and BlandAltman analysis. RESULTS Analyst 1 found 72 emboli in the 23 patients with a mean number of emboli of 3.13 per patient with a range of 0-11 emboli per patient. The clot volumes ranged from 0.0041-47.34 cm3(mean +/-SD, 5.93 +/-10.15 cm3). On the second read, analyst 1 found the same number and distribution of emboli with a range of volumes for read 2 from 0.0041 – 45.52 cm3(mean +/-SD, 5.42 +/-9.53 cm3). Analyst 2 found 73 emboli in the 23 patients with a mean number of emboli of 3.17 per patient with a range of 0-11 emboli per patient. The clot volumes ranged from 0.00459-46.29 cm3(mean +/-SD, 5.91 +/-10.06 cm3). Inter-and intraobserver variability measurements indicated excellent reproducibility of the semi-automated method for quantifying PE volume burden. ICC for all endpoints was greater than 0.95 for inter-and intra-observer analysis. Bland-Altman analysis indicated no significant biases.CONCLUSION Semi-automated region growing algorithm for quantifying PE is reproducible using data from multiple scanners and is a suitable method for image analysis in multicenter clinical trials. 展开更多
关键词 Pulmonary EMBOLISM ARTERIES Computed tomography angiography computer-assisted image analysis THROMBOLYTIC therapy
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Effect of varying computed tomography acquisition and reconstruction parameters on semi-automated clot volume quantification 被引量:3
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作者 Audrey E Kaufman Alison N Pruzan +4 位作者 Ching Hsu Sarayu Ramachandran Adam Jacobi Zahi A Fayad Venkatesh Mani 《World Journal of Radiology》 CAS 2018年第3期24-29,共6页
AIM To examine effects of computed tomography(CT)image acquisition/reconstruction parameters on clot volume quantification in vitro for research method validation purposes.METHODS This study was performed in conforman... AIM To examine effects of computed tomography(CT)image acquisition/reconstruction parameters on clot volume quantification in vitro for research method validation purposes.METHODS This study was performed in conformance with HIPAA and IRB Regulations(March 2015-November 2016).A ten blood clot phantom was designed and scanned on a dual-energy CT scanner(SOMATOM Force,Siemens Healthcare Gm BH,Erlangen,Germany)with varying pitch,iterative reconstruction,energy level and slicethickness.A range of clot and tube sizes were used in an attempt to replicate in vivo emboli found within central and segmental branches of the pulmonary arteries in patients with pulmonary emboli.Clot volume was the measured parameter and was analyzed by a single image analyst using a semi-automated region growing algorithm implemented in the FDA-approved Siemens syngo.via image analysis platform.Mixed model analysis was performed on the data.RESULTS On the acquisition side,the continuous factor of energy showed no statistically significant effect on absolute clot volume quantification(P=0.9898).On the other hand,when considering the fixed factor of pitch,there were statistically significant differences in clot volume quantification(P<0.0001).On the reconstruction side,with the continuous factor of reconstruction slice thickness no statistically significant effect on absolute clot volume quantification was demonstrated(P=0.4500).Also on the reconstruction side,with the fixed factor of using iterative reconstructions there was also no statistically significant effect on absolute clot volume quantification(P=0.3011).In addition,there was excellent R^2 correlation between the scale-measured mass of the clots both with respect to the CT measured volumes and with respect to volumes measure by the water displacement method.CONCLUSION Aside from varying pitch,changing CT acquisition parameters and using iterative reconstructions had no significant impact on clot volume quantification with a semi-automated region growing algorithm. 展开更多
关键词 Computed tomography ANGIOGRAPHY RADIOGRAPHIC phantom computer-assisted image analysis Pulmonary EMBOLISM THROMBOLYTIC therapy
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Factors correlating with acoustic radiation force impulse elastography in chronic hepatitis C 被引量:7
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作者 Toru Nishikawa Senju Hashimoto +13 位作者 Naoto Kawabe Masao Harata Yoshifumi Nitta Michihito Murao Takuji Nakano Yuko Mizuno Hiroaki Shimazaki Toshiki Kan Kazunori Nakaoka Yuka Takagawa Masashi Ohki Naohiro Ichino Keisuke Osakabe Kentaro Yoshioka 《World Journal of Gastroenterology》 SCIE CAS 2014年第5期1289-1297,共9页
AIM: To investigate the factors other than fibrosis stage correlating with acoustic radiation force impulse (ARFI) elastograpy in chronic hepatitis C.
关键词 Acoustic radiation force impulse Body mass index Chronic hepatitis C computer-assisted morphometric image analysis Fibrosis stage Hyaluronic acid Liver stiffness measurement Transient elastography Velocity of shear wave
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Retinal vessels caliber changes after strabismus surgery:results of 6mo follow-up 被引量:2
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作者 Ji-Peng Li Jing Fu +3 位作者 Jin-Qiong Zhou Xiao-Zhen Wang Wen-Ying Wang Ning-Pu Liu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第9期1325-1328,共4页
AIM:To evaluate the effect of strabismus surgery on retinal vessels calibers with digital color fundus photographs.METHODS:Two hundred consecutive strabismus patients underwent surgery,and 118 patients(female/male,... AIM:To evaluate the effect of strabismus surgery on retinal vessels calibers with digital color fundus photographs.METHODS:Two hundred consecutive strabismus patients underwent surgery,and 118 patients(female/male,55/63) who finished 6-month follow-up were finally included in this study.Optic disc-centered digital color fundus photographs of both eyes of all patients were taken prior to surgery and 6mo post surgery.The retinal vascular caliber of 116 operated eyes were measured using the computer program IVAN.The operated eyes were divided into 3 groups according to the surgical methods,recession of one muscle,one muscle recession and one muscle folding,one muscle resection and one muscle recession.The effect of number of altered muscles on retinal vessels was analyzed using statistic software SPSS 16.0.RESULTS:The mean age was 12.4±8.6y.Averaged central retinal artery equivalent(CRAE) of all patients was 120.31 ±23.02 μm preoperatively,and 122.87 ±15.93 μm six months after surgery.Averaged central retinal vein equivalent(CRVE) was 171.11 ±31.73 μm preoperatively and175.02±21.00 μm postoperatively.There was no significant difference of averaged CRAE(P=0.22) or CRVE(P=0.19)before and after operation.Averaged arteriole to venule ratio(AVR) was 0.71 ±0.07 before surgery and 0.70±0.07 after surgery.Comparison of preoperative and postoperative retinal vessels calibers among different surgical groups did not show significant differences.Also,there was no advantage of rectus muscle folding to muscle resection.CONCLUSION:Up to 6mo after strabismus surgery,the retinal vascular calibers were not altered.No more than two muscles in one surgery are safe for retinal perfusion. 展开更多
关键词 STRABISMUS retinal vascular caliber image processing computer-assisted
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内耳体素模型三维可视化 被引量:3
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作者 杨晓凯 吴曙智 陈晓素 《中国耳鼻咽喉头颈外科》 CSCD 2016年第11期668-670,共3页
内耳结构精细而复杂,位于颞骨岩部骨质内,又称为迷路,由半规管、前庭、耳蜗三部分组成。迷路内充满淋巴液,临床MRI检查可以获取清晰影像,但不能或仅能部分显示膜迷路结构-([1])。内耳三维可视化和空间方向测量对于临床和研究都非常重... 内耳结构精细而复杂,位于颞骨岩部骨质内,又称为迷路,由半规管、前庭、耳蜗三部分组成。迷路内充满淋巴液,临床MRI检查可以获取清晰影像,但不能或仅能部分显示膜迷路结构-([1])。内耳三维可视化和空间方向测量对于临床和研究都非常重要,其三维显示方式主要为表面绘制技术和体绘制技术。 展开更多
关键词 迷路(Labyrinth) 磁共振成像(Magnetic Resonance imaging) 成像 三维(imaging Three-Dimensional) 图像处理 计算机辅助(image Processing computer-assisted)
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