Volume 24, Issue 4

Hemodynamic factors are thought to be implicated in the progression and rupture of intracranial aneurysms. Current efforts aim to study the possible associations of hemodynamic characteristics such as complexity and stability of intra-aneurysmal flow patterns, size and location of the region of flow impingement with the clinical history of aneurysmal rupture. However, there are no reliable methods for measuring blood flow patterns in vivo. In this paper, an efficient methodology for patient-specific modeling and characterization of the hemodynamics in cerebral aneurysms from medical images is described. A sensitivity analysis of the hemodynamic characteristics with respect to variations of several variables over the expected physiologic range of conditions is also presented. This sensitivity analysis shows that although changes in the velocity fields can be observed, the characterization of the intra-aneurysmal flow patterns is not altered when the mean input flow, the flow division, the viscosity model, or mesh resolution are changed. It was also found that the variable that has the greater impact on the computed flow fields is the geometry of the vascular structures. We conclude that with the proposed modeling pipeline clinical studies involving large numbers cerebral aneurysms are feasible.

血流动力学因素被认为与颅内动脉瘤的进展和破裂有关。当前的研究旨在探究血流动力学特征（如动脉瘤内血流模式的复杂性和稳定性、血流冲击区域的大小和位置）与动脉瘤破裂临床史之间的可能关联。然而，目前尚无可靠的方法在体内测量血流模式。本文介绍了一种基于医学图像对脑动脉瘤血流动力学进行患者特异性建模和表征的高效方法。同时，还呈现了在预期生理条件下多个变量变化对血流动力学特征影响的敏感性分析。该敏感性分析表明，尽管可以观察到速度场的变化，但当平均输入流量、流量分配、黏度模型或网格分辨率改变时，动脉瘤内血流模式的表征并未改变。研究还发现，对计算流场影响最大的变量是血管结构的几何形状。我们得出结论，利用所提出的建模流程，涉及大量脑动脉瘤的临床研究是可行的。

In optoacoustic imaging, short laser pulses irradiate highly scattering human tissue and adiabatically heat embedded absorbing structures, such as blood vessels, to generate ultrasound transients by means of the thermoelastic effect. We present an optoacoustic vascular imaging system that records these transients on the skin surface with an ultrasound transducer array and displays the images onlin...

在光声成像中，短激光脉冲照射高度散射的人体组织，并绝热加热嵌入的吸收结构（如血管），通过热弹性效应产生超声瞬变。我们提出了一种光声血管成像系统，该系统利用超声换能器阵列在皮肤表面记录这些瞬变，并在线显示图像...

An automated image analysis method for quantification of in vitro angiogenesis is presented. The method is designed for in vitro angiogenesis assays that are based on co-culturing endothelial cells with fibroblasts. Such assays are used in many current studies in which anti-angiogenic agents for the treatment of cancer are being sought. This search requires accurate quantification of the stimulato...

提出了一种用于定量体外血管生成的自动图像分析方法。该方法专为基于内皮细胞与成纤维细胞共培养的体外血管生成实验而设计。此类实验用于许多当前寻求治疗癌症的抗血管生成药物的研究中。这种研究需要准确定量刺激物...

Vessel tree reconstruction in volumetric data is a necessary prerequisite in various medical imaging applications. Specifically, when considering the application of automated lung nodule detection in thoracic computed tomography (CT) scans, vessel trees can be used to resolve local ambiguities based on global considerations and so improve the performance of nodule detection algorithms. In this stu...

在体积数据中进行血管树重建是各种医学成像应用中的必要前提。具体来说，在考虑胸部计算机断层扫描（CT）中自动肺结节检测的应用时，血管树可用于基于全局考虑解决局部歧义，从而提高结节检测算法的性能。在本研究中...

The simulation of blood flow past endovascular devices such as coils and stents is a challenging problem due to the complex geometry of the devices. Traditional unstructured grid computational fluid dynamics relies on the generation of finite element grids that conform to the boundary of the computational domain. However, the generation of such grids for patient-specific modeling of cerebral aneur...

由于血管内装置（如线圈和支架）的几何形状复杂，模拟血液流过这些装置是一个具有挑战性的问题。传统的非结构化网格计算流体动力学依赖于生成符合计算域边界的有限元网格。然而，为脑动脉瘤的患者特异性模型生成此类网格...

This paper presents a new method for deformable model-based segmentation of lumen and thrombus in abdominal aortic aneurysms from computed tomography (CT) angiography (CTA) scans. First the lumen is segmented based on two positions indicated by the user, and subsequently the resulting surface is used to initialize the automated thrombus segmentation method. For the lumen, the image-derived deforma...

本文提出一种基于可变形模型的新方法，用于从计算机断层扫描（CT）血管造影（CTA）图像中分割腹主动脉瘤的管腔和血栓。首先根据用户指定的两个位置分割管腔，然后使用所得表面初始化自动血栓分割方法。对于管腔，基于图像的可变形...

We present a method for visualizing vasculature based on clinical computed tomography or magnetic resonance data. The vessel skeleton as well as the diameter information per voxel serve as input. Our method adheres to these data, while producing smooth transitions at branchings and closed, rounded ends by means of convolution surfaces. We examine the filter design with respect to irritating bulges...

我们提出了一种基于临床计算机断层扫描或磁共振数据的血管可视化方法。血管骨架及每个体素的直径信息作为输入。我们的方法遵循这些数据，同时通过卷积表面在分支处产生平滑过渡和封闭的圆形末端。我们研究了滤波设计以避免恼人的凸起...

A method for prospective motion correction of X-ray imaging of the heart is presented. A 3D+t coronary model is reconstructed from a biplane coronary angiogram obtained during free breathing. The deformation field is parameterized by cardiac and respiratory phase, which enables the estimation of the state of the arteries at any phase of the cardiac-respiratory cycle. The motion of the three-dimens...

提出了一种用于心脏X光成像的前瞻性运动校正方法。从自由呼吸期间采集的双平面冠状动脉造影中重建了一个3D+t冠状动脉模型。变形场由心脏和呼吸相位参数化，从而能够估计冠状动脉在心脏-呼吸周期任何相位时的状态。三维...

Intravascular ultrasound (IVUS) elastography visualizes local radial strain of arteries in so-called elastograms to detect rupture-prone plaques. However, due to the unknown arterial stress distribution these elastograms cannot be directly interpreted as a morphology and material composition image. To overcome this limitation we have developed a method that reconstructs a Young's modulus image fro...

血管内超声（IVUS）弹性成像在所谓的弹性图中可视化动脉的局部径向应变，以检测易破裂的斑块。然而，由于未知的动脉应力分布，这些弹性图不能直接解释为形态和材料组成图像。为了克服这一限制，我们开发了一种方法，该方法重建杨氏模量图像...

We propose an anatomy-based approach for an efficient construction of a three-dimensional human normal cerebral arterial model from segmented and skeletonized angiographic data. The centerline-based model is used for an accurate angiographic data representation. A vascular tree is represented by tubular segments and bifurcations whose construction takes into account vascular anatomy. A bifurcation...

我们提出了一种基于解剖学的方法，从分割和骨架化的血管造影数据中高效构建三维人类正常脑动脉模型。基于中心线的模型用于精确的血管造影数据表示。血管树由管状段和分叉表示，其构建考虑了血管解剖学。一个分叉...

We have developed two new algorithms for the measurement of blood flow from dynamic X-ray angiographic images. Both algorithms aim to improve on existing techniques. First, a model-based (MB) algorithm is used to constrain the concentration-distance curve matching approach. Second, a weighted optical flow algorithm (OP) is used to improve on point-based optical flow methods by averaging velocity e...

我们开发了两种新的算法，用于从动态X射线血管造影图像中测量血流。两种算法都旨在改进现有技术。首先，基于模型（MB）的算法用于约束浓度-距离曲线匹配方法。其次，加权光流算法（OP）用于通过平均速度来改进基于点的光流方法...

The association between vascular wall shear stress (WSS) and the local development of atherosclerotic plaque makes estimation of in vivo WSS of considerable interest. Three-dimensional ultrasound (3DUS) combined with computational fluid dynamics (CFD) provides a potentially valuable tool for acquiring subject-specific WSS, but the interoperator and intraoperator variability associated with WSS cal...

血管壁剪切应力（WSS）与动脉粥样硬化斑块局部发展之间的关联使得体内WSS的估算具有相当大的意义。三维超声（3DUS）与计算流体动力学（CFD）相结合为获取个体特异性WSS提供了潜在有价值的工具，但与WSS计算相关的操作者间和操作者内变异性...

Provides a listing of current staff, committee members and society officers.

提供当前工作人员、委员会成员及学会官员名单。

Provides notice of upcoming special issue(s) of interest to practitioners and researchers.

向从业者和研究人员提供即将出版的专题特刊的通知。

Provides notice of upcoming conference events of interest to practitioners and researchers.

提供关于即将举行的会议活动的通知，这些活动对从业者和研究人员具有吸引力。

Describes the above-named upcoming conference event. May include topics to be covered or calls for papers.

描述上述即将举行的会议事件。可能包括涵盖的主题或征文通知。

Provides instructions and guidelines to prospective authors who wish to submit manuscripts.

为有意投稿的作者提供指导和说明。

Presents the table of contents for this issue of the periodical.

呈现本期刊物的目录。