Volume 27, Issue 11

We propose an automatic four-chamber heart segmentation system for the quantitative functional analysis of the heart from cardiac computed tomography (CT) volumes. Two topics are discussed: heart modeling and automatic model fitting to an unseen volume. Heart modeling is a nontrivial task since the heart is a complex nonrigid organ. The model must be anatomically accurate, allow manual editing, and provide sufficient information to guide automatic detection and segmentation. Unlike previous work, we explicitly represent important landmarks (such as the valves and the ventricular septum cusps) among the control points of the model. The control points can be detected reliably to guide the automatic model fitting process. Using this model, we develop an efficient and robust approach for automatic heart chamber segmentation in 3-D CT volumes. We formulate the segmentation as a two-step learning problem: anatomical structure localization and boundary delineation. In both steps, we exploit the recent advances in learning discriminative models. A novel algorithm, marginal space learning (MSL), is introduced to solve the 9-D similarity transformation search problem for localizing the heart chambers. After determining the pose of the heart chambers, we estimate the 3-D shape through learning-based boundary delineation. The proposed method has been extensively tested on the largest dataset (with 323 volumes from 137 patients) ever reported in the literature. To the best of our knowledge, our system is the fastest with a speed of 4.0 s per volume (on a dual-core 3.2-GHz processor) for the automatic segmentation of all four chambers.

我们提出了一种用于心脏计算机断层扫描（CT）容积定量功能分析的自动四腔心分割系统。讨论了两个主题：心脏建模和对未知容积的自动模型拟合。心脏建模是一项非平凡的任务，因为心脏是一个复杂的非刚性器官。模型必须解剖学准确，允许手动编辑，并提供足够的信息来指导自动检测和分割。与以往的工作不同，我们在模型的控制点中显式地表示了重要的标志点（如瓣膜和室间隔尖）。这些控制点可以可靠地检测到，以指导自动模型拟合过程。利用该模型，我们开发了一种高效且鲁棒的方法，用于三维CT容积中的自动心脏腔室分割。我们将分割公式化为一个两步学习问题：解剖结构定位和边界描绘。在这两个步骤中，我们利用了判别模型学习的最新进展。引入了一种新颖的算法——边缘空间学习（MSL）来解决用于定位心腔的9维相似变换搜索问题。在确定心腔的姿态后，我们通过基于学习的边界描绘来估计三维形状。该方法已在文献报道的最大数据集（来自137名患者的323个容积）上进行了广泛测试。据我们所知，我们的系统是最快的，所有四个腔室的自动分割速度为每个容积4.0秒（在双核3.2-GHz处理器上）。

Current ultrasound methods for measuring myocardial strain are often limited to measurements in one or two dimensions. Cardiac motion and deformation however are truly 3-D. With the introduction of matrix transducer technology, 3-D ultrasound imaging of the heart has become feasible but suffers from low temporal and spatial resolution, making 3-D strain estimation challenging. In this paper, it is...

当前测量心肌应变的超声方法通常局限于一个或两个维度。然而，心脏的运动和变形实际上是三维的。随着矩阵换能器技术的引入，心脏的三维超声成像已成为可能，但受限于较低的时间和空间分辨率，使得三维应变估计具有挑战性。本文...

Current magnetic resonance imaging (MRI) technology allows the determination of patient-individual coronary tree structure, detection of infarctions, and assessment of myocardial perfusion. Joint inspection of these three aspects yields valuable information for therapy planning, e.g., through classification of myocardium into healthy tissue, regions showing a reversible hypoperfusion, and infarcti...

当前的磁共振成像（MRI）技术允许确定患者个体化的冠状动脉树结构、检测梗死以及评估心肌灌注。联合检查这三个方面可为治疗计划提供有价值的信息，例如通过将心肌分类为健康组织、显示可逆性低灌注的区域以及梗死区...

This paper presents a novel method for registration of cardiac perfusion magnetic resonance imaging (MRI). The presented method is capable of automatically registering perfusion data, using independent component analysis (ICA) to extract physiologically relevant features together with their time-intensity behavior. A time-varying reference image mimicking intensity changes in the data of interest ...

本文提出了一种用于心脏灌注磁共振成像（MRI）配准的新方法。该方法能够自动配准灌注数据，使用独立成分分析（ICA）提取生理相关特征及其时间-强度行为。一个时变参考图像模拟感兴趣数据中的强度变化...

We present an adaptive algorithm which uses a fast electrophysiological (EP) model to estimate apparent electrical conductivity and local conduction velocity from noncontact mapping of the endocardial surface potential. Development of such functional imaging revealing hidden parameters of the heart can be instrumental for improved diagnosis and planning of therapy for cardiac arrhythmia and heart ...

我们提出了一种自适应算法，该算法使用快速电生理模型，通过心内膜表面电位的非接触标测来估计表观电导率和局部传导速度。开发这种揭示心脏隐藏参数的功能成像，有助于改善心律失常和心脏病的诊断和治疗规划。

Three-dimensional (3-D) cardiac activation imaging (3-DCAI) is a recently developed technique that aims at imaging the activation sequence throughout the the ventricular myocardium. 3-DCAI entails the modeling and estimation of the cardiac equivalent current density (ECD) distribution from which the activation time at any myocardial site is determined as the time point with the peak amplitude of l...

三维心脏激活成像（3-DCAI）是一种近期发展的技术，旨在成像整个心室心肌的激活序列。3-DCAI涉及对心脏等效电流密度（ECD）分布的建模和估计，从中任何心肌部位的激活时间被确定为具有峰值幅度的时间点...

A 3-D reconstruction of the coronary arteries offers great advantages in the diagnosis and treatment of cardiovascular disease, compared to 2-D X-ray angiograms. Besides improved roadmapping, quantitative vessel analysis is possible. Due to the heart's motion, rotational coronary angiography typically provides only 5-10 projections for the reconstruction of each cardiac phase, which leads to a str...

与传统二维X射线血管造影相比，三维冠状动脉重建在心血管疾病的诊断和治疗中具有显著优势。除了改进的路径规划外，还可以进行定量血管分析。由于心脏运动，旋转冠状动脉造影通常仅提供每个心动周期5-10个投影用于重建，这导致...

Due to the small size of training sets, statistical shape models often over-constrain the deformation in medical image segmentation. Hence, artificial enlargement of the training set has been proposed as a solution for the problem to increase the flexibility of the models. In this paper, different methods were evaluated to artificially enlarge a training set. Furthermore, the objectives were to st...

由于训练集规模较小，统计形状模型在医学图像分割中常常过度约束形变。因此，本文提出人工扩充训练集作为解决方案，以增加模型的灵活性。本文评估了不同的训练集人工扩充方法。此外，目标是...

Active shape models bear a great promise for model-based medical image analysis. Their practical use, though, is undermined due to the need to train such models on large image databases. Automatic building of point distribution models (PDMs) has been successfully addressed and a number of autolandmarking techniques are currently available. However, the need for strategies to automatically build in...

主动形状模型在基于模型的医学图像分析中具有巨大潜力。然而，由于需要在大型图像数据库上训练此类模型，其实用性受到影响。点分布模型（PDM）的自动构建已成功解决，目前已有多种自动标记技术可用。然而，自动构建强度模型策略的需求仍然存在...

Three-dimensional (3-D) stress echocardiography is a novel technique for diagnosing cardiac dysfunction. It involves evaluating wall motion of the left ventricle, by visually analyzing ultrasound images obtained in rest and in different stages of stress. Since the acquisitions are performed minutes apart, variabilities may exist in the visualized cross-sections. To improve anatomical correspondenc...

三维（3-D）应力超声心动图是一种诊断心脏功能异常的新技术。它通过视觉分析在静息和不同应力阶段获取的超声图像来评估左心室壁的运动。由于采集间隔几分钟，可视化的截面可能存在变异性。为改善解剖对应...

The diagnosis of cardiac disease using dual-isotope myocardial perfusion SPECT (MPS) is based on the defect status in both stress and rest images, and can be modeled as a three-class task of classifying patients as having no, reversible, or fixed perfusion defects. Simultaneous acquisition protocols for dual-isotope MPS imaging have gained much interest due to their advantages including perfect re...

使用双同位素心肌灌注SPECT（MPS）诊断心脏疾病基于负荷和静息图像中的缺损状态，可以建模为将患者分类为无缺损、可逆缺损或固定缺损的三类任务。同时采集双同位素MPS成像方案因其包括完美重...等优势而受到广泛关注。

The 11 papers in this special issue focus on the functional imaging of the heart and the rapid progression of all modalities towards 4-D imaging.

本特刊的11篇论文聚焦于心脏功能成像以及所有模态向4D成像的快速进展。

Provides a listing of current committee members and society officers.

提供当前委员会成员和学会官员的列表。

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

为有意投稿的作者提供手稿提交的说明和指南。

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广告：质量不妥协。

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广告：IEEE，自1884年起引领该领域。

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本页或这些页特意留空。

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

介绍本期期刊的目录。