Volume 34, Issue 11

Ultrafast ultrasonic imaging is a rapidly developing field based on the unfocused transmission of plane or diverging ultrasound waves. This recent approach to ultrasound imaging leads to a large increase in raw ultrasound data available per acquisition. Bigger synchronous ultrasound imaging datasets can be exploited in order to strongly improve the discrimination between tissue and blood motion in the field of Doppler imaging. Here we propose a spatiotemporal singular value decomposition clutter rejection of ultrasonic data acquired at ultrafast frame rate. The singular value decomposition (SVD) takes benefits of the different features of tissue and blood motion in terms of spatiotemporal coherence and strongly outperforms conventional clutter rejection filters based on high pass temporal filtering. Whereas classical clutter filters operate on the temporal dimension only, SVD clutter filtering provides up to a four-dimensional approach (3D in space and 1D in time). We demonstrate the performance of SVD clutter filtering with a flow phantom study that showed an increased performance compared to other classical filters (better contrast to noise ratio with tissue motion between 1 and 10mm/s and axial blood flow as low as 2.6 mm/s). SVD clutter filtering revealed previously undetected blood flows such as microvascular networks or blood flows corrupted by significant tissue or probe motion artifacts. We report in vivo applications including small animal fUltrasound brain imaging (blood flow detection limit of 0.5 mm/s) and several clinical imaging cases, such as neonate brain imaging, liver or kidney Doppler imaging.

超快超声成像是一个快速发展的领域，基于平面或发散超声波的非聚焦发射。这种最新的超声成像方法使得每次采集可获得的原始超声数据大幅增加。可以利用更大的同步超声成像数据集来强有力地改善多普勒成像中组织和血液运动的区分。本文提出了一种对超快帧率采集的超声数据进行时空奇异值分解杂波抑制的方法。奇异值分解（SVD）利用了组织和血液运动在时空相干性方面的不同特征，并且比基于高通时间滤波的传统杂波抑制滤波器性能更强。经典杂波滤波器仅在时间维度上操作，而SVD杂波滤波提供了高达四维（三维空间和一维时间）的方法。我们通过流动体模研究展示了SVD杂波滤波的性能，与其他经典滤波器相比，其性能有所提高（在组织运动1-10毫米/秒和轴向血流低至2.6毫米/秒的情况下具有更好的对比度噪声比）。SVD杂波滤波揭示了先前未检测到的血流，例如微血管网络或受到显著组织或探头运动伪影影响的血流。我们报告了体内应用，包括小动物功能性超声脑成像（血流检测极限为0.5毫米/秒）以及几个临床成像案例，如新生儿脑成像、肝脏或肾脏多普勒成像。

In this paper, we present a stochastic model for glandular structures in histology images of tissue slides stained with Hematoxylin and Eosin, choosing colon tissue as an example. The proposed Random Polygons Model (RPM) treats each glandular structure in an image as a polygon made of a random number of vertices, where the vertices represent approximate locations of epithelial nuclei. We formulate...

本文以结肠组织为例，提出了一种针对苏木精-伊红染色的组织切片中腺体结构的随机模型。所提出的随机多边形模型（RPM）将图像中的每个腺体结构视为由随机数量顶点构成的多边形，其中顶点代表上皮细胞核的大致位置。我们构建...

Combining Positron Emission Tomography (PET) with Magnetic Resonance Imaging (MRI) results in a promising hybrid molecular imaging modality as it unifies the high sensitivity of PET for molecular and cellular processes with the functional and anatomical information from MRI. Digital Silicon Photomultipliers (dSiPMs) are the digital evolution in scintillation light detector technology and promise h...

将正电子发射断层扫描（PET）与磁共振成像（MRI）相结合，产生了一种有前景的混合分子成像模态，因为它将PET对分子和细胞过程的高灵敏度与MRI的功能和解剖信息统一起来。数字硅光电倍增管（dSiPM）是闪烁光探测器技术的数字演进，有望...

Recent achievement of the learning-based classification leads to the noticeable performance improvement in automatic polyp detection. Here, building large good datasets is very crucial for learning a reliable detector. However, it is practically challenging due to the diversity of polyp types, expensive inspection, and labor-intensive labeling tasks. For this reason, the polyp datasets usually ten...

近期基于学习的分类的成就使得自动息肉检测的性能显著提升。在此，构建大规模高质量的数据集对于学习可靠的检测器至关重要。然而，由于息肉类型的多样性、昂贵的检查以及劳动密集型的标注任务，这在实际中具有挑战性。因此，息肉数据集通常只有...

Diffusion MRI offers the unique opportunity of assessing the structural connections of human brains in vivo. With the advance of diffusion MRI technology, multi-shell imaging methods are becoming increasingly practical for large scale studies and clinical application. In this work, we propose a novel method for the analysis of multi-shell diffusion imaging data by incorporating compartment models ...

弥散磁共振成像为评估人脑在体内的结构连接提供了独特的机会。随着弥散磁共振成像技术的进步，多壳层成像方法在大规模研究和临床应用中变得越来越实用。在这项工作中，我们提出了一种新的方法，通过结合隔室模型来分析多壳层弥散成像数据……

In magnetic resonance imaging-based electrical properties tomography (MREPT), tissue electrical properties (EPs) are derived from the spatial variation of the transmit RF field (B1+). Here we derive theoretically the relationship between the signal-to-noise ratio (SNR) of the electrical properties obtained by MREPT and the SNR of the input B1+ data, under the assumption that the latter is much gre...

在基于磁共振成像的电特性层析成像（MREPT）中，组织电特性（EPs）从发射射频场（B1+）的空间变化中推导得出。在此，我们理论推导了在输入B1+数据的信噪比远大于...的情况下，由MREPT获得的电特性信噪比与输入B1+数据信噪比之间的关系。

This paper presents the derivation of the Epipolar Consistency Conditions (ECC) between two X-ray images from the Beer-Lambert law of X-ray attenuation and the Epipolar Geometry of two pinhole cameras, using Grangeat's theorem. We motivate the use of Oriented Projective Geometry to express redundant line integrals in projection images and define a consistency metric, which can be used, for instanc...

本文基于X射线衰减的比尔-朗伯定律和两个针孔相机的对极几何，利用Grangeat定理推导了两幅X射线图像之间的对极一致性条件（ECC）。我们激励使用有向投影几何来表达投影图像中的冗余线积分，并定义了一个一致性度量，该度量可用于例如...

In dual energy CT (DECT), noise amplification during signal decomposition significantly limits the utility of basis material images. Since clinically relevant objects typically contain a limited number of different materials, we propose an Image-domain Decomposition method through Entropy Minimization (IDEM) for noise suppression in DECT. Pixels of decomposed images are first linearly transformed ...

在双能CT（DECT）中，信号分解过程中的噪声放大严重限制了基物质图像的实用性。由于临床相关对象通常包含有限数量的不同物质，我们提出了一种通过熵最小化的图像域分解方法（IDEM）用于DECT中的噪声抑制。分解图像的像素首先经过线性变换...

This paper presents the results of a computer-aided intervention solution to demonstrate the application of RF time series for characterization of prostate cancer, in vivo. Methods: We pre-process RF time series features extracted from 14 patients using hierarchical clustering to remove possible outliers. Then, we demonstrate that the mean central frequency and wavelet features extracted from a gr...

本文介绍了一种计算机辅助介入解决方案的结果，以展示射频时间序列在体内前列腺癌表征中的应用。方法：我们对14名患者提取的射频时间序列特征进行预处理，使用层次聚类去除可能的异常值。然后，我们展示了从网格...

Positron range (PR) is a significant factor that limits PET image resolution, especially with some radionuclides currently used in clinical and preclinical studies such as 82Rb, 124I and 68Ga. The use of an accurate model of the PR in the image reconstruction may minimize its impact on the image quality. Nevertheless, PR distributions are difficult to model, as they may be different at each voxel ...

正电子射程（PR）是限制PET图像分辨率的重要因素，尤其在使用当前临床和临床前研究中常用的一些放射性核素（如82Rb、124I和68Ga）时。在图像重建中使用精确的PR模型可以最小化其对图像质量的影响。然而，PR分布难以建模，因为它们在每个体素处可能不同……

In surface-based registration for image-guided interventions, the presence of missing data can be a significant issue. This often arises with real-time imaging modalities such as ultrasound, where poor contrast can make tissue boundaries difficult to distinguish from surrounding tissue. Missing data poses two challenges: ambiguity in establishing correspondences; and extrapolation of the deformati...

在基于表面的图像引导干预配准中，缺失数据的存在可能是一个重要问题。这在实时成像模态（如超声）中经常出现，其中对比度差使得组织边界难以与周围组织区分。缺失数据带来了两个挑战：建立对应关系的模糊性；以及变形外推...

Measurements of plaque stiffness may provide important prognostic and diagnostic information to help clinicians distinguish vulnerable plaques containing soft lipid pools from more stable, stiffer plaques. In this preliminary study, we compare in vivo ultrasonic Acoustic Radiation Force Impulse (ARFI) imaging derived measures of carotid plaque stiffness with composition determined by spatially reg...

斑块硬度的测量可能提供重要的预后和诊断信息，帮助临床医生区分含有软脂池的易损斑块和更稳定、更硬的斑块。在这项初步研究中，我们比较了体内超声声辐射力脉冲成像衍生的颈动脉斑块硬度与空间配准MRI确定的成分。

Pharmacokinetic analysis of dynamic positron emission tomography (PET) imaging data maps the measured time activity curves to a set of model-specific pharmacokinetic parameters. Voxel-based parameter estimation via curve fitting is conventionally performed indirectly on a sequence of independently reconstructed PET images, leading to high variance and bias in the parametric images. We propose a di...

动态正电子发射断层扫描（PET）成像数据的药代动力学分析将测量的时间活度曲线映射到一组模型特定的药代动力学参数。基于体素的参数估计通常通过曲线拟合间接对一系列独立重建的PET图像进行，导致参数图像中的高方差和偏差。我们提出了一种...

We demonstrate a new method to recover 4D blood flow over the entire ventricle from partial blood velocity measurements using multiple 3D+t colour Doppler images and ventricular wall motion estimated using 3D+t BMode images. We apply our approach to realistic simulated data to ascertain the ability of the method to deal with incomplete data, as typically happens in clinical practice. Experiments u...

我们展示了一种新方法，利用多个3D+t彩色多普勒图像和通过3D+t B模式图像估计的心室壁运动，从部分血流速度测量中恢复整个心室的4D血流。我们将该方法应用于逼真的模拟数据，以评估其处理临床实践中常见的不完整数据的能力。实验...

A new Cardiac Electrical Sparse Imaging (CESI) technique is proposed to image cardiac activation throughout the three-dimensional myocardium from body surface electrocardiogram (ECG) with the aid of individualized heart-torso geometry. The sparse property of cardiac electrical activity in the time domain is utilized in the temporal sparse promoting inverse solution, one formulated to achieve highe...

提出了一种新的心脏电稀疏成像（CESI）技术，利用个体化的心脏-躯干几何结构，从体表心电图（ECG）对三维心肌中的心脏激活进行成像。时间域中心脏电活动的稀疏性被用于时间稀疏促进逆解，该解被公式化以实现高...

The estimation of myocardial blood flow (MBF) by 13N-ammonia or 82Rb dynamic PET typically relies on an empirically determined generalized Renkin-Crone equation to relate the kinetic parameter K1 to MBF. Because the Renkin-Crone equation defines MBF as an implicit function of K1, the MBF variance cannot be determined using standard error propagation techniques. To overcome this limitation, we deri...

通过13N-氨或82Rb动态PET估计心肌血流量（MBF）通常依赖于经验确定的广义Renkin-Crone方程，该方程将动力学参数K1与MBF联系起来。由于Renkin-Crone方程将MBF定义为K1的隐函数，因此无法使用标准误差传播技术确定MBF方差。为了克服这一限制，我们推导...

Neuroimaging techniques can measure structural and functional brain connectivity with unprecedented detail in vivo. This so-called brain connectome can be represented as high dimensional matrices corresponding to edge weights in graphs. After measuring the matrices of two cohorts (i.e., patients and healthy controls), one is often required to formulate computational network models for effective fe...

神经影像技术能够在体内以前所未有的细节测量结构和功能性大脑连接。这种所谓的脑连接组可以表示为对应于图中边权重的高维矩阵。在测量两个队列（即患者和健康对照）的矩阵后，通常需要制定计算网络模型以实现有效的特征提取和分类。

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这些指南为准备在本刊发表论文的作者提供了指导。介绍了在本期刊发表文章的作者须知。

Provides a listing of the editors, board members, and current staff for this issue of the publication.

提供本期出版物编辑、编委会成员及在职人员名单。

Prospective authors are requested to submit new, unpublished manuscripts for inclusion in the upcoming event described in this call for papers.

诚邀潜在作者提交新的未发表手稿，以便纳入本次征文通知所述的即将举行的活动中。

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展示本期出版物的目录。

Prospective authors are requested to submit new, unpublished manuscripts for inclusion in the upcoming event described in this call for papers.

诚邀各位作者提交新的、未发表的手稿，以便纳入本次征稿通知中所述的即将举行的活动。