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The effect of subbranch for the quantification of local hemodynamic environment in the coronary artery:a computed tomography angiography–based computational fluid dynamic analysis

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Emergency and Critical Care Medicine 2022年第4期2卷 181-190页

作者： Yibing Shi Jin Zheng Ning Yang Yang Chen Jingxi Sun Ying Zhang Xuanxuan Zhou Yongguang Gao Suqing Li Haijing Zhu Julio Acosta-Cabronero Ping Xia zhongzhao teng Department of Radiology Xuzhou Central HospitalXuzhou Clinical School of Xuzhou Medical UniversityXuzhouJiangsuChina Department of Radiology University of CambridgeUnited Kingdom Nanjing Jingsan Medical Science and Technology LtdJiangsuChina PLA Rocket Force Characteristic Medical Centre BeijingChina Tenoke LtdCambridgeUnited Kingdom.

Background:Hemodynamic parameters derived from computed tomography angiography–based computational fluid dynamics(CFD)analysis have been widely used for clinical decision-making and researches to assess the vulnerability of atherosclerotic plaques and explain the initialization and development of *** in the CFD model might affect the accuracy of hemodynamic parameters,but the effectiveness has been least ***:A coronary artery baseline model was generated with focal stenosis at the proximal left anterior descending *** comparing models were created by systematically removing various subbranches to examine the changes in hemodynamic parameters,including time-averaged pressure(TAP),time-averaged wall shear stress(TAWSS),oscillatory shear index(OSI),and particle relative residence time(RRT).Changes in these parameters were assessed quantitatively around the stenosis and near the region where subbranches were ***:The removal of subbranches caused a significant change in outflow rate,and there was generally a decrease in all CFD parameters in the regions of interest with a decrease in outflow *** subbranch removal had a significant impact on the calculation of TAWSS,OSI,and RRT,whereas TAP was insensitive to the removal with approximately 0.25%variation in all 19 *** local effect from removing branch segments generally became negligible after 5 diameters away from the cutting-off position,but the decrease could be affected by other factors,such as a large ***:The outflow rate is a dominant factor for the calculation of TAP,TAWSS,OSI,and *** of subbranches has a minor effect on the TAP calculation,but its effect is considerable on the TAWSS,OSI,and *** effect of subbranch removal is limited in a region with 5 local diameters.

关键词： Coronary artery Hemodynamics Pressure Shear stress Side branch Stenosis

Study on cartilaginous and muscular strains of rat trachea

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Science China(Life Sciences) 2004年第6期47卷 485-493页

作者： teng zhongzhao1, LIU Zhaorong1, LIN Yihan1, WANG Yiqin2, LI Fufeng2 & GONG Keqin1 1. Department of Mechanics & Engineering Science, Fudan University, Shanghai 200433, China 2. Shanghai Traditional Medical University, Shanghai 200032, China Correspondence should be addressed to teng zhongzhao Department of Mechanics & Engineering Science Fudan UniversityShanghai 200433China Shanghai Traditional Medical University Shanghai 200032China

This paper introduces a new method, termed Twice Cutting, for obtaining the zero-stress states of cartilage and muscle of trachea. The method applied cuts at the two junc- tions of tracheal cartilage and muscle perpendicular to the tangent lines of cartilage at its tips. The cartilaginous and muscular opening angles are defined for the first time in Twice Cutting methods. Based on the analysis of cartilaginous and muscular geometric information in no-load and zero-stress states, it is found that there are compressive and tensile residual strains in the inner and outer walls of the cartilage respectively. Residual strains at the muscular inner wall of tracheal rings near bifurcation are negative, whereas those of other rings are positive, and re- sidual strains at outer wall of all rings are positive. This phenomenon of tracheal muscle residual strains is different from those of vessel etc. The results also show that the absolute values of cartilaginous strains are considerably smaller than that of muscular ones, with the ratio being around 0.05. The values of all the tracheal parameters, including residual strains and opening angles, are reducing with the increasing value of tracheal rings’ position. So the consequences obtained in this paper not only indicate that the trachea is a non-uniform tissue along the circumferential and axial directions, but also reveal the differences between the trachea and other living tissues, such as vessel, esophagus. This is a basic research for further work, such as determining stress in trachea, to which the cartilaginous and muscular zero-stress states should be referred.

关键词： trachea, residual strain, opening angle, remodeling.

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The role of porosity and 3D cross-stent configuration of multiple overlapping uncovered stents in the management of complex aortic aneurysms-Insights from haemodynamics

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Medicine in Novel Technology and Devices 2019年第3期3卷 34-42页

作者： Shuo Wang Yongxue Zhang Jianxuan Feng Yuan Huang Pinjing Hui Jonathan H.Gillard Qingsheng Lu zhongzhao teng Department of Radiology University of CambridgeUK Department of Vascular Surgery Changhai HospitalShanghaiChina EPSRC Centre for Mathematical and Statistical Analysis of Multimodal Clinical Imaging University of CambridgeUK Department of Stroke Center The First Affiliated Hospital of Soochow UniversitySuzhouChina Department of Engineering University of CambridgeUK Beijing Advanced Innovation Center for Biomedical Engineering Beihang UniversityBeijingChina

Background:Multiple overlapping uncovered stents(MOUS)have been introduced to manage complex aortic aneurysms with vital branches *** has been shown that the porosity is a key determinant of the treatment ***,the role of 3D cross-stent configuration remains ***:One patient with a complex aortic aneurysm judged not suitable for open surgery nor endovascular repair was invited to participate this *** total,four bare metal stents were deployed.3D lesion geometry was reconstructed based on pre-and post-operative CTA,and the zero-pressure configuration was recovered using an inverse *** haemodynamic parameters,including wall shear stress(WSS),oscillatory shear index(OSI),and particle relative resident time(RRT),as well as the vessel structural stress(VSS),were quantified using one-way fluid-structure interaction(FSI)*** comparison to MOUS,a corresponding compact model was reconstructed by projecting inner layer stents to the most outer layer to form a single layer to eliminate the 3D cross-stent configuration and one-way FSI analysis was ***:Results obtained showed that the porosity decreased linearly with the number of *** the 1st stent was deployed,the mean velocity decreased 36.4%and further reduction of 49.3%,59.8%,and 62.8%were observed when the 2nd,3rd and 4th stents were *** also decreased with the number of stents deployed,and both OSI and RRT increased,but the increase was very minor with the 4th *** deployment induced high VSS concentration in the landing zone while the VSS and pressure in the sac remained nearly *** compact model yielded a small difference in the value of flow-related parameters and 10%–20%reduction in ***:Compared with porosity,the 3D cross-stent of MOUS configuration plays a minor role in the modulation of local haemodynamics.A compact model does not reduce high VSS concentration in the diseased region significantly.

关键词： Aortic aneurysm Bare metal stent Branch Porosity Mechanics

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影像技术在动脉粥样硬化性疾病中的应用进展

中国动脉硬化杂志 2022年第1期30卷 77-82页

作者：史张刘崎滕忠照陆建平海军军医大学第一附属医院上海市200433 剑桥大学影像学系剑桥郡英国

随着全身血管成像技术的迅速发展,动脉粥样硬化所形成的血管狭窄和斑块能够达到可视化定性及定量评估。多模态成像可通过评估血管壁斑块的组成和代谢过程来进行心脑血管风险的预测。本文概述了当前影像技术在动脉粥样硬化性疾病中的应... 详细信息

随着全身血管成像技术的迅速发展,动脉粥样硬化所形成的血管狭窄和斑块能够达到可视化定性及定量评估。多模态成像可通过评估血管壁斑块的组成和代谢过程来进行心脑血管风险的预测。本文概述了当前影像技术在动脉粥样硬化性疾病中的应用进展。

关键词：动脉粥样硬化超声计算机断层扫描磁共振分子影像

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基于双解码器网络的岩心CT图像分割

智能计算机与应用 2024年第2期14卷 156-161页

作者：陈忠照滕奇志吴晓红何海波四川大学电子信息学院成都610065 成都西图科技有限公司成都610065

在石油地质领域,分析岩心内部微观孔隙结构的形态分布、特征参数,对研究油气资源的渗流特性和储集性能具有重要意义。岩心CT图像具有噪点多、比度低、亮度不均匀的特点,目前实际工程运用的孔隙提取方法,仍然存在着需要大量人工交互且分... 详细信息

在石油地质领域,分析岩心内部微观孔隙结构的形态分布、特征参数,对研究油气资源的渗流特性和储集性能具有重要意义。岩心CT图像具有噪点多、比度低、亮度不均匀的特点,目前实际工程运用的孔隙提取方法,仍然存在着需要大量人工交互且分割精度较低的问题。针对这些问题,本文提出了基于双解码器网络的分割方法,构建了岩心CT图像分割数据集,用图像预处理网络分支,辅助训练图像分割网络。实验结果表明,本方法的模型参数量仅有33.3 MB,像素精度PA能达到91.41%,平均检测交并比MIoU能达到85.32%,具有模型小、推理速度快、分割精度高的优点。

关键词：岩心CT图像图像分割深度学习

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Tracheal compliance and limit flow rate changes in a murine model of asthma

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Science China(Life Sciences) 2008年第10期51卷 922-931页

作者： teng zhongzhao1, WANG YiQin2, LI FuFeng2, YAN HaiXia2 & LIU ZhaoRong3 1 Department of Mathematical Sciences, Worcester Polytechnic Institute, Worcester, MA, 01609, USA 2 Syndrome Laboratory of TCM, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China 3 Department of Mechanics and Engineering Science, Fudan University, Shanghai 200433, China Department of Mathematical Sciences Worcester Polytechnic Institute Worcester USA Syndrome Laboratory of TCM Shanghai University of Traditional Chinese Medicine Shanghai China Department of Mechanics and Engineering Science Fudan University Shanghai China

Trachea is the unique passage for air to flow in and out. Its tone is of importance for the respiration system. However, investigation on how tracheal tone changes due to asthma is limited. Aiming at studying how the mechanical property changes due to asthma as well as the compliance and flow limitation, the following methods are adopted. Static and passive pressure-volume tests of rats' trachea of the asthmatic and control groups are carried out and a new type of tube law is formulated to fit the experimental data, based on which changes of compliance and limit flow rate are investigated. In order to give explanation to such changes, histological examinations with tracheal soft tissues are made. The results show that compliance, limit flow rate and material constants included in the tube law largely depend on the longitudinal stretching ratio. Compared with the control group, the tracheal compliance of asthmatic animals decreases significantly, which results in an increased limit flow rate. Histological studies indicate that asthma can lead to hyperplasia/hypertrophy of smooth muscle cells, and increase elastin and collagen fibres in the muscular membrane. Though decreasing compliance increases sta- bility, during the onset of asthma, limit flow rate is much smaller due to the lower transmural pressure. Asthma leads to a stiffer trachea and the obtained results reveal some aspects relevant to asthma-induced tracheal remodelling.

关键词： trachea asthma collapse tube law compliance limit flow rate remodelling

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