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Microscopy cell image analysis is a fundamental tool for biological research. In particular, multivariate fluorescence microscopy is used to observe different aspects of cells in cultures. It is still common practice to perform analysis tasks by visual inspection of individual cells which is time consuming, exhausting and prone to induce subjective bias. This makes automatic cell image analysis essential for large scale, objective studies of cell cultures. Traditionally the task of automatic cell analysis is approached through the use of image segmentation methods for extraction of cells' locations and shapes. Image segmentation, although fundamental, is neither an easy task in computer vision nor is it robust to image quality changes. This makes image segmentation for cell detection semi-automated requiring frequent tuning of parameters. We introduce a new approach for cell detection and shape estimation in multivariate images based on the sliding band filter (SBF). This filter's design makes it adequate to detect overall convex shapes and as such it performs well for cell detection. Furthermore, the parameters involved are intuitive as they are directly related to the expected cell size. Using the SBF filter we detect cells' nucleus and cytoplasm location and shapes. Based on the assumption that each cell has the same approximate shape center in both nuclei and cytoplasm fluorescence channels, we guide cytoplasm shape estimation by the nuclear detections improving performance and reducing errors. Then we validate cell detection by gathering evidence from nuclei and cytoplasm channels. Additionally, we include overlap correction and shape regularization steps which further improve the estimated cell shapes. The approach is evaluated using two datasets with different types of data: a 20 images benchmark set of simulated cell culture images, containing 1000 simulated cells; a 16 images Drosophila melanogaster Kc167 dataset containing 1255 cells, stained for DNA and actin. Both image datasets present a difficult problem due to the high variability of cell shapes and frequent cluster overlap between cells. On the Drosophila dataset our approach achieved a precision/recall of 95%/69% and 82%/90% for nuclei and cytoplasm detection respectively and an overall accuracy of 76%.

显微细胞图像分析是生物学研究的基本工具。特别是，多变量荧光显微镜用于观察培养细胞的不同方面。目前，通过视觉检查单个细胞来执行分析任务仍然是常见做法，这既耗时又容易产生主观偏差。这使得自动细胞图像分析对于大规模、客观的细胞培养研究至关重要。传统上，自动细胞分析的任务通过使用图像分割方法提取细胞的位置和形状来实现。图像分割虽然是基础，但在计算机视觉中并非易事，也不鲁棒于图像质量变化。这使得用于细胞检测的图像分割半自动化，需要频繁调整参数。本文提出了一种基于滑动带滤波器（SBF）的多变量图像中细胞检测和形状估计的新方法。该滤波器的设计使其足以检测整体凸形状，因此在细胞检测中表现良好。此外，涉及的参数直观，因为它们直接与预期的细胞大小相关。使用SBF滤波器，我们检测细胞核和细胞质的位置和形状。基于每个细胞在细胞核和细胞质荧光通道中具有近似相同形状中心的假设，我们通过核检测指导细胞质形状估计，提高性能并减少误差。然后通过从核和细胞质通道收集证据来验证细胞检测。此外，我们还包括重叠校正和形状正则化步骤，进一步改进估计的细胞形状。该方法使用两个不同类型的数据集进行评估：一个包含1000个模拟细胞的20张模拟细胞培养图像基准集；一个包含1255个细胞、标记DNA和肌动蛋白的16张黑腹果蝇Kc167数据集。由于细胞形状的高度变异和细胞之间频繁的簇重叠，这两个图像数据集都提出了难题。在果蝇数据集上，我们的方法在核检测和细胞质检测上分别达到了95%/69%和82%/90%的精确率/召回率，总体准确率为76%。

From a set of longitudinal three-dimensional scans of the same anatomical structure, the authors have accurately modeled the temporal shape and size changes using a linear shape model. On a total of 31 computed tomography scans of the mandible from six patients, 14,851 semilandmarks are found automatically using shape features and a new algorithm called geometry-constrained diffusion. The semiland...

作者利用一组同一解剖结构的纵向三维扫描，通过线性形状模型精确模拟了时间上的形状和大小变化。基于六名患者的31次下颌骨CT扫描，使用形状特征和一种名为几何约束扩散的新算法自动找到了14851个半地标。半地标...

To noninvasively quantify tissue elasticity for differentiating malignancy of soft tissue, the authors previously proposed a two-dimensional (2-D) mechanical inverse problem in which simultaneous partial differential equations (PDE's) represented the target distribution globally of relative shear moduli with respect to reference shear moduli such that the relative values could be determined from s...

为了无创量化组织弹性以区分软组织恶性，作者先前提出了一个二维（2-D）力学逆问题，其中联立偏微分方程（PDE）全局地表示了相对于参考剪切模量的相对剪切模量目标分布，从而可以从应变测量确定相对值...

This paper describes the usefulness of computer assistance in the acquisition of "good" images for stenosis diagnosis and quantification in coronary angiography. The system recommends the optimal viewpoints from which stenotic lesions can be observed clearly based on images obtained from initial viewpoints. First, the viewpoint dependency of the apparent severity of a stenotic lesion is experiment...

本文描述了计算机辅助在冠状动脉造影中获取用于狭窄诊断和量化的“良好”图像方面的实用性。该系统根据从初始视点获取的图像，推荐能够清晰观察狭窄病变的最佳视点。首先，通过实验研究了狭窄病变表观严重程度的视点依赖性...

This paper presents microwave tomographic reconstructions of the complex permittivity of lossy dielectric objects immersed in water from experimental multiview near-field data obtained with a 2.35-GHz planar active microwave camera. An iterative reconstruction algorithm based on the Levenberg-Marquardt method was used to solve the nonlinear matrix equation which results when applying a moment meth...

本文介绍了利用2.35 GHz平面有源微波相机获得的实验多视近场数据，对浸没在水中的有耗介电物体的复介电常数进行微波层析重建。采用基于Levenberg-Marquardt方法的迭代重建算法来求解应用矩量法时产生的非线性矩阵方程...

This paper describes research work motivated by an innovative medical application: computer-assisted transbronchial biopsy. This project involves the registration, with no external localization device, of a preoperative three-dimensional (3-D) computed tomography (CT) scan of the thoracic cavity (showing a tumor that requires a needle biopsy), and an intraoperative endoscopic two-dimensional (2-D)...

本文描述了由一项创新医学应用（计算机辅助经支气管活检）所驱动的研究工作。该项目涉及在无外部定位设备的情况下，将术前三维胸部CT扫描（显示需要针吸活检的肿瘤）与术中二维内镜图像进行配准...

The performance of photoacoustic microscopy (PAM) degrades due to the turbidity of the skull that introduces attenuation and distortion of both laser and stimulated ultrasound. In this manuscript, we demonstrated that a newly developed skull optical clearing solution (SOCS) could enhance not only the transmittance of light, but also that of ultrasound in the skull in vitro. Thus the photoacoustic ...

由于颅骨的混浊性导致激光和激发超声的衰减和畸变，光声显微镜（PAM）的性能下降。在本文中，我们证明了一种新开发的颅骨光学透明溶液（SOCS）不仅能增强颅骨中光的透过率，还能增强超声的透过率（体外实验）。因此，光声...

Describes a probabilistic framework for modeling single-trial functional magnetic resonance (fMR) images based on a parametric model for the hemodynamic response and Markov random field (MRF) image models. The model is fitted to image data by maximizing a lower bound on the log likelihood. The result is an approximate maximum a posteriori estimate of the joint distribution over the model parameter...

描述了一个基于血流动力学反应参数模型和马尔可夫随机场(MRF)图像模型对单次试验功能磁共振图像进行概率建模的框架。该模型通过最大化对数似然的下界来拟合图像数据。结果是对模型参数联合分布的近似最大后验估计。

This paper describes fusion of three-dimensional (3-D) ultrasound (US) and magnetic resonance imaging (MRI) data sets, without the assistance of external fiducial markers or external position sensors. Fusion of these two modalities combines real-time 3-D ultrasound scans of soft tissue with the larger anatomical framework from MRI. The complementary information available from multiple imaging moda...

本文描述了在不使用外部基准标记或外部位置传感器的情况下，三维超声与磁共振成像数据集的融合。这两种模态的融合将软组织的实时三维超声扫描与MRI提供的更大解剖框架相结合。多模态成像提供的互补信息...

Many image-reconstruction methods have been proposed to improve the spatial resolution of positron emission tomography (PET) images and, thus, to produce better quantification. However, these techniques, which are designed for static images, may be inadequate for good reconstruction from dynamic data. The authors present a simple, but effective, reconstruction approach intended specifically for dy...

已提出许多图像重建方法来提高正电子发射断层扫描（PET）图像的空间分辨率，从而产生更好的量化结果。然而，这些专为静态图像设计的技术可能不足以从动态数据中实现良好的重建。作者提出了一种简单而有效的重建方法，专门用于动态...

Presents a validation study of an optical-flow method for the rapid estimation of myocardial displacement in magnetic resonance tagged cardiac images. This registration and change visualization (RCV) software uses a hierarchical estimation technique to compute the flow field that describes the warping of an image of one cardiac phase into alignment with the next. This method overcomes the requirem...

介绍了一种用于快速估计磁共振标记心脏图像中心肌位移的光流方法的验证研究。该配准与变化可视化（RCV）软件使用分层估计技术来计算描述一个心脏相位图像变形以与下一个相位对齐的光流场。该方法克服了需要...

A convolutional backprojection algorithm is derived for a fan beam geometry that has its center-of-rotation displaced from the midline of the fan beam. In single photon emission computed tomography (SPECT), where a transaxial converging collimator is used with a rotating gamma camera, it is difficult to precisely align the collimator so that the mechanical center-of-rotation is colinear with the m...

中文摘要翻译待生成

In this article, multiresolution analysis, specifically the discrete wavelet transform modulus-maxima (mod-max) method, is utilized for the extraction of mammographic mass shape features. These shape features are used in a classification system to classify masses as round, nodular, or stellate. The multiresolution shape features are compared with traditional uniresolution shape features for their ...

本文采用多分辨率分析，特别是离散小波变换模极大值（mod-max）方法，用于提取乳腺肿块形状特征。这些形状特征用于分类系统，将肿块分为圆形、结节状或星状。将多分辨率形状特征与传统的单分辨率形状特征进行比较...

Advances in visualization technology and specialized graphic workstations allow clinicians to virtually interact with anatomical structures contained within sampled medical-image datasets. A hindrance to the effective use of this technology is the difficult problem of image segmentation. In this paper, the authors utilize a recently proposed oscillator network called the locally excitatory globall...

可视化技术和专业图形工作站的进步使得临床医生能够与采样医学图像数据集中的解剖结构进行虚拟交互。有效利用这一技术的障碍是图像分割这一难题。在本文中，作者利用了一种最近提出的振荡器网络，称为局部兴奋全局...

Motion and deformation analysis of the myocardium are of utmost interest in cardiac imaging. Part of the research is devoted to the estimation of the heart function by analysis of the shape changes of the left-ventricular endocardial surface. However, most clinically used shape-based approaches are often two-dimensional (2-D) and based on the analysis of the shape at only two cardiac instants. Thr...

心肌的运动和形变分析在心脏成像中至关重要。部分研究致力于通过分析左心室内膜表面的形状变化来评估心脏功能。然而，大多数临床使用的基于形状的方法通常是二维（2-D）的，并且仅基于两个心脏瞬间的形状分析。...

Describes a method for identification of brain structures from MRI data sets. The bulk of the paper concerns an automatic system for finding the anterior and posterior commissures [(AC) and (PC)] in the midsagittal plane. These landmarks are key for the definition of the Talairach space, commonly used in stereotactic neurosurgery, in the definition of common coordinate systems for the pooling of f...

描述了一种从MRI数据集中识别脑结构的方法。论文主要涉及一个自动系统，用于在正中矢状面上寻找前连合和后连合。这些标志点对于定义Talairach空间至关重要，该空间常用于立体定向神经外科以及定义用于汇总数据的共同坐标系。

An approach for tracking and quantifying the nonrigid, nonuniform motion of the left ventricular (LV) endocardial wall from two-dimensional (2-D) cardiac image sequences, on a point-by-point basis over the entire cardiac cycle, is presented. Given a set of boundaries, motion computation involves first matching local segments on one contour to segments on the next contour in the sequence using a sh...

提出了一种在整个心动周期中逐点追踪和量化左心室心内膜壁非刚性、非均匀运动的方法，该方法基于二维心脏图像序列。给定一组边界，运动计算首先涉及使用形状匹配将一个轮廓上的局部段与序列中下一个轮廓上的段进行匹配。

We present for the first time a full three-dimensional (3-D) reconstruction of absorption images of breast from continuous-wave (cw) measurements performed on a premenopausal woman. Our 3-D optical images clearly reveal a large primary tumor as well as a small secondary tumor in a separate location of the breast. The multiple tumors identified by our 3-D optical imaging have been confirmed by the ...

我们首次展示了在一位绝经前女性身上进行的连续波（CW）测量所得到的乳腺吸收图像的全三维（3D）重建。我们的3D光学图像清晰地揭示了乳腺内一个大的原发肿瘤以及另一个位置的一个小的继发肿瘤。我们的3D光学成像识别出的多个肿瘤已通过...得到证实。

This paper reports the results of a complete circumferential scan of a human tooth and its underlying dentino-enamel junction using ultrasound at frequencies in the 10-MHz range. The imagery shows clearly a two-dimensional contour of the dentino-enamel junction with a depth and lateral resolution of approximately 100 /spl mu/m and 750 /spl mu/m, respectively. The resulting sonograph is compared wi...

本文报道了使用10 MHz频率范围内的超声波对人体牙齿及其下方的牙本质-釉质连接处进行完整圆周扫描的结果。图像清晰地显示了牙本质-釉质连接的二维轮廓，深度分辨率约为100微米，横向分辨率约为750微米。生成的声像图与...进行比较。

Proposes and validates the hypothesis that one can use differential shape properties of the myocardial surfaces to recover dense field motion from standard three-dimensional (3-D) image sequences (MRI and CT). Quantitative measures of left ventricular regional function can be further inferred from the point correspondence maps. The noninvasive, algorithm-derived results are validated on two levels...

提出并验证了一种假设，即可以利用心肌表面的微分形状特性从标准三维（3-D）图像序列（MRI和CT）中恢复密集场运动。进一步可以从点对应图中推断出左心室区域功能的定量测量。无创、算法推导的结果在两个层面上得到验证...

A technique for the contrast enhancement of a picture is proposed. The method is derived from the entropy concept of information theory. The originality of the algorithm rests on the use of a local contrast to define the digital entropy. The basic idea of the treatment is to enhance the contrast by transforming the global entropy. The same technique can also be used for an adaptive smoothing proce...

中文摘要翻译待生成

A simple and yet effective method for finding the borders of tumors is presented as an initial step towards the diagnosis of skin tumors from their color images. The method makes use of an adaptive color metric from the red, green, and blue planes that contains information for discriminating the tumor from the background. Using this suitable coordinate transformation, the image is segmented. The t...

中文摘要翻译待生成

This paper presents a new nonrigid monomodality image registration algorithm based on $B$-splines. The deformation is described by a cubic $B$-spline field and found by minimizing the energy between a reference image and a deformed version of a floating image. To penalize noninvertible transformation, we propose two different constraints on the Jacobian of the transformation and its derivatives. T...

本文提出了一种基于B样条的非刚性单模态图像配准算法。变形由三次B样条场描述，并通过最小化参考图像与浮动图像变形版本之间的能量来求解。为了惩罚不可逆变换，我们提出了两种不同的约束条件，分别作用于变换的雅可比矩阵及其导数。...

In recent years, many investigators have proposed Gibbs prior models to regularize images reconstructed from emission computed tomography data. Unfortunately, hyperparameters used to specify Gibbs priors can greatly influence the degree of regularity imposed by such priors and, as a result, numerous procedures have been proposed to estimate hyperparameter values, from observed image data. Many of ...

近年来，许多研究者提出使用吉布斯先验模型来正则化从发射计算机断层扫描数据重建的图像。不幸的是，用于指定吉布斯先验的超参数会极大影响这些先验所施加的正则化程度，因此，已提出许多从观测图像数据估计超参数值的方法。许多...