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X射线图像和CT图像的多维配准

电子学报 2002年第10期30卷 1573-1576页

作者：张惠 pascal haigron 舒华忠罗立民东南大学生物医学工程系影像实验室江苏南京210096 法国雷恩第一大学信号与图像处理实验室法国雷恩35042

在本文中 ,我们提出了一种基于Chamfer3 4距离变换和Powell优化的方法 ,用于X射线图像和CT图像间的配准 .该方法首先从X射线图像中分割出目标物体 .通过使用投影模型和优化方法 ,得到了准确的投影矩阵 .该方法同样被用于医学介入手术中 ... 详细信息

在本文中 ,我们提出了一种基于Chamfer3 4距离变换和Powell优化的方法 ,用于X射线图像和CT图像间的配准 .该方法首先从X射线图像中分割出目标物体 .通过使用投影模型和优化方法 ,得到了准确的投影矩阵 .该方法同样被用于医学介入手术中 ,处理从三维图像工作站中获取的主动漫游的数据 .

关键词：校准矩阵图像分割距离变换 Powell优化 X射线图像 CT图像多维配准

VIRTUAL REALITY BASED THREE-DIMENSIONAL GUIDE WIRE PROPAGATION SIMULATION FOR ENDOVASCULAR INTERVENTION

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Transactions of Nanjing University of Aeronautics and Astronautics 2010年第1期27卷 62-69页

作者：周正东 pascal haigron Vincent Guilloux Antoine Lucas 南京航空航天大学材料科学与技术学院法国国家健康与医学研究院雷恩第一大学信号与图像处理实验室中法生物医学信息研究中心法国国家健康与医学研究院临床高新技术研究中心雷恩第一大学附属医院

The virtual reality based motion simulation of the guide wire and the catheter inside specific vascular structures can benefit a lot for the endovascular intervention. A fast and well-performed collision cancellation algorithm is proposed based on the geometric analysis and the angular propagation （AP）, and a 3-D real-time interactive system is developed for the motion simulation of the guide wire and the catheter inside the specific patient vascular. The guide wire or the catheter is modeled as the ＂multi-body＂ representation and properties are defined by its intrinsic characteristics. The motion of the guide wire or the catheter inside the vascular is guided by the collision detection and the collision cancellation algorithm. Finally, a relaxation procedure is used to achieve more realistic status. Experimental results show that the behavior of the guide wire or the catheter depends on the defined parameters. The real-time simulation can be achieved. The result shows that the simulation system is effective and promising.

关键词： catheters virtual reality guide wire multi-body model endovascular intervention

FEM model for real-time guide wire simulation in vasculature

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Journal of Southeast University(English Edition) 2008年第1期24卷 50-54页

作者：张秋葵 pascal haigron 罗立民舒华忠东南大学影像科学与技术试验室南京210096 雷恩第一大学信号与图像处理实验室法国雷恩35042

A model suitable for describing the mechanical response of thin elastic objects is proposed to simulate the deformation of guide wires in minimally invasive interventions. The main objective of this simulation is to provide doctors an opportunity to rehearse the surgery and select an optimal operation plan before the real surgery. In this model the guide wire is discretized with the multi-body representation and its elastic energy derivate from elastic theory is a polynomial function of the nodal displacements. The vascular structure is represented by a tetrahedron mesh extended from the triangular mesh of the artery, which can be extracted from the patient＇s CT image data. The model applies the energy decline process of the conjugate gradient method to the deformation simulation of the guide wire. Experimental results show that the polynomial relationship between elastic energy and nodal displacements tremendously simplifies the evaluation of the conjugate gradient method and significantly improves the model＇s efficiency. Compared with models depending on an explicit scheme for evaluation, the new model is not only non-conditionally stable but also more efficient. The model can be applied to the real-time simulation of guide wire in a vascular structure.

关键词： deformable model finite element method real-time simulation guide wire

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基于场景分析的交互式漫游

东南大学学报（自然科学版） 2001年第2期31卷 18-22页

作者：张惠傅瑶 pascal haigron 罗立民东南大学影像科学与技术实验室南京210096 法国雷恩第一大学信号与图像处理实验室雷恩35042

从CT和MRI设备中获取的三维体积图像 ,允许我们对三维解剖结构进行任意的观察 .一般主动漫游的路径计算方法 ,都是基于中轴提取等算法的 .本文在光线跟踪模型进行绘制的基础上 ,提出了一种基于深度场景分析的路径计算方法 ,通过交互选... 详细信息

从CT和MRI设备中获取的三维体积图像 ,允许我们对三维解剖结构进行任意的观察 .一般主动漫游的路径计算方法 ,都是基于中轴提取等算法的 .本文在光线跟踪模型进行绘制的基础上 ,提出了一种基于深度场景分析的路径计算方法 ,通过交互选择得到了沿管状器官内部进行漫游的路径 ,并将其应用到了虚拟内窥镜系统当中 .

关键词：主动漫游光线跟踪深度场景分析虚拟内窥镜交互式漫游

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交互式虚拟内窥镜系统

中国图象图形学报（A辑） 2002年第1期7卷 36-43页

作者：张惠舒华忠 pascal haigron 罗立民东南大学生物医学工程系影象科学与技术实验室南京210096 法国雷恩第一大学信号与图象处理实验室雷恩35042

计算机图形图象技术与虚拟现实技术应用于医学内窥镜系统 ,产生了虚拟内窥镜技术 ,为了将虚拟现实技术应用在医学图象处理方面 ,以方便医生进行虚拟手术与无创诊断 .在综合利用各种计算机图形、图象技术的基础上 ,提出了完整的交互式虚... 详细信息

计算机图形图象技术与虚拟现实技术应用于医学内窥镜系统 ,产生了虚拟内窥镜技术 ,为了将虚拟现实技术应用在医学图象处理方面 ,以方便医生进行虚拟手术与无创诊断 .在综合利用各种计算机图形、图象技术的基础上 ,提出了完整的交互式虚拟内窥镜系统的框架 ,同时对系统结构和各种模型进行了分析和讨论 ,还针对系统的实时性和绘制结果的逼真性要求 ,提出了基于 Object Cache和扩展的区域增长方法 ,并将其应用到医学图象处理当中 ,得到了较好的效果 .该系统较好地解决了虚拟现实与可视化中实时性和绘制精度两方面的要求。

关键词：计算机图形学虚拟现实虚拟内窥镜 Object Cache 扩展区域增长法医学图象可视化医学内窥镜

Projection registration of X-ray image and CT image

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Journal of Southeast University(English Edition) 2003年第1期19卷 26-30页

作者：张惠罗立民舒华忠李松毅 pascal haigron 东南大学生物科学与医学工程系南京2113096 法国雷恩第一大学信号与图像处理实验室法国雷恩35042

A methodology for alignment of an X-ray image and a CT image, based on the Chamfer 3-4 distance transform and simulated annealing optimization algorithm is presented. Firstly, an initial transformation matrix is constructed. For the convenience of computing, geometric models of the X-ray device to reconstruct the calibration matrix are used. Then, by defining the distance between the 3-D protective and the 2-D object image, we optimize this distance matching problem, using the simulated annealing algorithm. This method is also integrated into medical intra-operation, dealing with the data set acquired from 3-D image workstation and active navigation.

关键词： image registration calibration matrix image segmentation distance transformation simulated annealing

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γ-射线血管内照射治疗计划系统的研制

东南大学学报（自然科学版） 2002年第4期32卷 586-589页

作者：於文雪李松毅 pascal haigron 罗立民 Antoine Lucas Cecile Moisan 东南大学生物科学与医学工程系南京210096 LaboratoireTraitementduSignaletdel’Image

介绍了研究开发的三维血管内照射治疗计划系统 .该治疗计划系统建立在三维医学图像和临床上常用的γ射线源基础之上 ,集成了放射源剂量学数据管理、三维图像处理、治疗计划设计、剂量分布计算与显示、治疗计划评估和打印输出等功能模块 ... 详细信息

介绍了研究开发的三维血管内照射治疗计划系统 .该治疗计划系统建立在三维医学图像和临床上常用的γ射线源基础之上 ,集成了放射源剂量学数据管理、三维图像处理、治疗计划设计、剂量分布计算与显示、治疗计划评估和打印输出等功能模块 .为了验证治疗计划的有效性 ,文中给出了 2组实验数据 ,一组是与GammaMed治疗计划系统的对比结果。

关键词：血管内照射治疗计划系统剂量分布计算三维图像处理冠状动脉粥样硬化性心脏病 γ-射线研制

Long-COVID-19: the persisting imprint of SARS-CoV-2 infections on the innate immune system

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Signal Transduction and Targeted Therapy 2024年第1期9卷 12-13页

作者： Marianne Boes pascal Falter-Braun Center for Translational Immunology and Department of Pediatric Immunology University Medical Center UtrechtUtrecht UniversityUtrechtThe Netherlands Institute of Network Biology(INET) Molecular Targets and Therapeutics Center(MTTC)Helmholtz MunichNeuherbergGermany Microbe-Host Interactions Faculty of BiologyLudwig-Maximilians-Universität MünchenPlanegg-MartinsriedGermany

In a recent Cell publication,Cheong et *** how COVID-19 causes IL-6 induced epigenetic reprogramming of human immune stem cells,which causes lasting alterations in the composition and response characteristics of circulating immune cells.1 The study provides important insights into the mechanisms by which SARSCoV-2 infections impact the human immune system and is an important hook into unraveling the mechanisms of post-acute sequelae of COVID-19(PASC)commonly referred to as longCOVID.

关键词： system COV programming

On-the-fly precision spectroscopy with a dual-modulated tunable diode laser and Hz-level referencing to a cavity

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Advanced Photonics 2024年第4期6卷 36-44页

作者： Shuangyou Zhang Toby Bi pascal Del’Haye Max Planck Institute for the Science of Light Friedrich-Alexander Universit?t Erlangen-Nürnberg Department of Physics

Advances in laser spectroscopy have enabled many scientific breakthroughs in physics, chemistry,biology, and astronomy. Optical frequency combs pushed measurement limits with ultrahigh-frequency accuracy and fast-measurement speed, while tunable-diode-laser spectroscopy is used in scenarios that require high power and continuous spectral coverage. Despite these advantages of tunable-diode-laser spectroscopy, it is challenging to precisely determine the instantaneous laser frequency because of fluctuations in the scan speed. Here, we demonstrate a simple spectroscopy scheme with a frequencymodulated diode laser that references the laser on-the-fly to a fiber cavity. The fiber cavity's free spectral range is on-the-fly calibrated with sub-10-Hz frequency precision. We achieve a relative precision of the laser frequency of 2 × 10-8for an 11-THz frequency range at a measurement speed of 1 THz∕s. This is an improvement of more than 2 orders of magnitude compared to existing diode-laser-spectroscopy *** scheme provides precise frequency calibration markers, while simultaneously tracking the instantaneous scan speed of the laser. We demonstrate the versatility of our method through various applications, including dispersion measurement of a fiber, ultrahigh-Q microresonators, and spectroscopy of a hydrogen fluoride gas cell. The simplicity, robustness, and low cost of this spectroscopy scheme are valuable for out-of-the-lab applications like lidar and environmental monitoring.

关键词： frequency comb gas spectroscopy integrated photonics radio-frequency modulation tunable laser spectroscopy