Volume 36, Issue 6

Colonoscopy is the gold standard for colon cancer screening though some polyps are still missed, thus preventing early disease detection and treatment. Several computational systems have been proposed to assist polyp detection during colonoscopy but so far without consistent evaluation. The lack of publicly available annotated databases has made it difficult to compare methods and to assess if they achieve performance levels acceptable for clinical use. The Automatic Polyp Detection sub-challenge, conducted as part of the Endoscopic Vision Challenge (http://endovis.grand-challenge.org) at the international conference on Medical Image Computing and Computer Assisted Intervention (MICCAI) in 2015, was an effort to address this need. In this paper, we report the results of this comparative evaluation of polyp detection methods, as well as describe additional experiments to further explore differences between methods. We define performance metrics and provide evaluation databases that allow comparison of multiple methodologies. Results show that convolutional neural networks are the state of the art. Nevertheless, it is also demonstrated that combining different methodologies can lead to an improved overall performance.

结肠镜检查是结肠癌筛查的金标准，但有些息肉仍会被漏检，从而阻碍了疾病的早期发现和治疗。人们提出了几种计算机辅助系统来帮助结肠镜检查中的息肉检测，但至今缺乏一致的评估。公开可用的标注数据库的缺乏使得难以比较不同方法，并评估它们是否达到临床可接受的性能水平。作为2015年国际医学图像计算和计算机辅助介入会议（MICCAI）上内窥镜视觉挑战赛（http://endovis.grand-challenge.org）的一部分，自动息肉检测子挑战赛旨在解决这一需求。在本文中，我们报告了这项息肉检测方法比较评估的结果，并描述了进一步探索方法间差异的附加实验。我们定义了性能指标并提供了允许比较多种方法的评估数据库。结果表明，卷积神经网络是目前最先进的技术。尽管如此，也证明了结合不同方法可以提高整体性能。

Echocardiography (echo) is a skilled technical procedure that depends on the experience of the operator. The aim of this paper is to reduce user variability in data acquisition by automatically computing a score of echo quality for operator feedback. To do this, a deep convolutional neural network model, trained on a large set of samples, was developed for scoring apical four-chamber (A4C) echo. I...

超声心动图是一项依赖于操作者经验的技术性检查。本文旨在通过自动计算超声心动图质量评分以提供操作者反馈，从而减少数据采集中的用户变异性。为此，我们开发了一个深度卷积神经网络模型，该模型在大量样本上进行了训练，用于对心尖四腔切面超声心动图进行评分。

This paper presents an automated measurement of spine curvature by using prior knowledge on vertebral anatomical structures in ultrasound volume projection imaging (VPI). This method can be used in scoliosis assessment with free-hand 3-D ultrasound imaging. It is based on the extraction of bony features from VPI images using a newly proposed two-fold thresholding strategy, with information of the ...

本文提出了一种利用超声容积投影成像（VPI）中椎骨解剖结构的先验知识自动测量脊柱曲率的方法。该方法可用于自由手三维超声成像中的脊柱侧弯评估。它基于使用新提出的双阈值策略从VPI图像中提取骨骼特征，并利用...

Cerenkov luminescence tomography (CLT) provides a novel technique for 3-D noninvasive detection of radiopharmaceuticals in living subjects. However, because of the severe scattering of Cerenkov light, the reconstruction accuracy and stability of CLT is still unsatisfied. In this paper, a modified weight multispectral CLT (wmCLT) reconstruction strategy was developed which split the Cerenkov radiat...

切伦科夫发光断层成像（CLT）为活体放射性药物的三维无创检测提供了一种新技术。然而，由于切伦科夫光的严重散射，CLT的重建精度和稳定性仍不令人满意。本文提出了一种改进的加权多光谱CLT（wmCLT）重建策略，该策略将切伦科夫辐射...

Optoacoustic (photoacoustic) dermoscopy offers two principal advantages over conventional optical imaging applied in dermatology. First, it yields high-resolution cross-sectional images of the skin at depths not accessible to other non-invasive optical imaging methods. Second, by resolving absorption spectra at multiple wavelengths, it enables label-free 3D visualization of morphological and funct...

光声皮肤镜检查相比应用于皮肤科的常规光学成像有两个主要优势。首先，它能在其他非侵入性光学成像方法无法达到的深度获得皮肤的高分辨率横截面图像。其次，通过解析多个波长的吸收光谱，它能够实现形态和功能的免标记三维可视化。

Accurate quantification of retinal structures in 3-D optical coherence tomography data of eyes with pathologies provides clinically relevant information. We present an approach to jointly segment retinal layers and lesions in eyes with topology-disrupting retinal diseases by a loosely coupled level set framework. In the new approach, lesions are modeled as an additional space-variant layer delinea...

对病理眼睛的三维光学相干断层扫描数据中的视网膜结构进行精确量化可提供临床相关信息。我们提出了一种通过松散耦合水平集框架对拓扑破坏性视网膜疾病患者的视网膜层和病变进行联合分割的方法。在新方法中，病变被建模为额外的空间变异层，并描绘...

The development of ultrafast ultrasound imaging offers great opportunities to improve imaging technologies, such as shear wave elastography and ultrafast Doppler imaging. In ultrafast imaging, there are tradeoffs among image signal-to-noise ratio (SNR), resolution, and post-compounded frame rate. Various approaches have been proposed to solve this tradeoff, such as multiplane wave imaging or the a...

超快超声成像的发展为改善成像技术提供了巨大机遇，例如剪切波弹性成像和超快多普勒成像。在超快成像中，图像信噪比、分辨率和复合后帧率之间存在权衡。已经提出了多种方法来解决这种权衡，例如多平面波成像或...

A multi-modality imaging-based modeling approach was used to study complex unsteady hemodynamics and lesion growth in a dissecting abdominal aortic aneurysm model. We combined in vivo ultrasound (geometry and flow) and in vitro optical coherence tomography (OCT) (geometry) to obtain the high resolution needed to construct detailed hemodynamic simulations over large portions of the murine vasculatu...

采用基于多模态成像的建模方法，研究了小鼠夹层腹主动脉瘤模型中复杂的非稳态血流动力学和病变生长。我们结合了体内超声（几何和血流）与体外光学相干断层扫描（OCT）（几何），以获得构建小鼠血管系统大部分区域详细血流动力学模拟所需的高分辨率。

This paper presents and analyzes an alternative formulation of the locally low-rank (LLR) regularization framework for magnetic resonance image (MRI) reconstruction. Generally, LLR-based MRI reconstruction techniques operate by dividing the underlying image into a collection of matrices formed from image patches. Each of these matrices is assumed to have low rank due to the inherent correlations a...

本文介绍并分析了一种用于磁共振图像（MRI）重建的局部低秩（LLR）正则化框架的替代公式。通常，基于LLR的MRI重建技术通过将底层图像划分为由图像块形成的矩阵集合来运行。由于固有的相关性，每个矩阵都被假定为低秩...

A model of cardiac microstructure and diffusion MRI is presented, and compared with experimental data from ex vivo rat hearts. The model includes a simplified representation of individual cells, with physiologically correct cell size and orientation, as well as intra- to extracellular volume ratio. Diffusion MRI is simulated using a Monte Carlo model and realistic MRI sequences. The results show g...

提出了一个心脏微结构和扩散MRI的模型，并与离体大鼠心脏的实验数据进行了比较。该模型包括对单个细胞的简化表示，具有生理学上正确的细胞大小和方向，以及细胞内到细胞外的体积比。使用蒙特卡罗模型和真实的MRI序列模拟扩散MRI。结果显示...

Most strain imaging techniques follow a pipeline strategy: in the first step, tissue displacement is estimated from radio-frequency (RF) frames, and in the second step, a spatial derivative operation is applied. There are two main issues that arise from this framework. First, the gradient operation amplifies noise, and therefore, smoothing techniques have to be adopted. Second, strain estimation d...

大多数应变成像技术采用流水线策略：第一步，从射频（RF）帧估计组织位移；第二步，进行空间导数运算。这种框架存在两个主要问题。首先，导数运算会放大噪声，因此必须采用平滑技术。其次，应变估计d...

R*2 mapping is a useful tool in blood-oxygen-level dependent fMRI due to its quantitative-nature. However, like T*2-weighted imaging, standard R*2 mapping based on multi-echo EPI suffers from geometric distortion, due to strong off-resonance near the air-tissue interface. Joint mapping of R*2 and off-resonance can correct the geometric distortion and is less susceptible to motion artifacts. Single...

R*2映射因其定量特性在血氧水平依赖的功能磁共振成像中是一种有用的工具。然而，与T*2加权成像类似，基于多回波EPI的标准R*2映射由于空气-组织界面附近的强失调共振而遭受几何畸变。R*2和失调共振的联合映射可以校正几何畸变，并且不易受运动伪影影响。单...

Quantitative positron emission tomography imaging often requires correcting the image data for deformable motion. With cyclic motion, this is traditionally achieved by separating the coincidence data into a relatively small number of gates, and incorporating the inter-gate image transformation matrices into the reconstruction algorithm. In the presence of non-cyclic deformable motion, this approac...

定量正电子发射断层成像通常需要校正图像数据中的变形运动。对于周期性运动，传统方法是将符合数据分成相对较少的门控，并将门间图像变换矩阵纳入重建算法。在非周期性变形运动存在的情况下，这种方法...

We propose an automated pipeline for vessel centerline extraction in 3-D computed tomography angiography (CTA) scans with arbitrary fields of view. The principal steps of the pipeline are body part detection, candidate seed selection, segment tracking, which includes centerline extraction, and vessel tree growing. The final tree-growing step can be instantiated in either a semi- or fully automated...

我们提出了一种自动管道，用于在任意视野的三维计算机断层扫描血管造影（CTA）扫描中提取血管中心线。管道的主要步骤包括身体部位检测、候选种子选择、段追踪（包括中心线提取）以及血管树生长。最后的血管树生长步骤可以以半自动或全自动方式实例化...

Extraction of image-based biomarkers, such as the presence, visibility, or thickness of a certain layer, from 3-D optical coherence tomography data provides relevant clinical information. We present a method to simultaneously determine the number of visible layers in the outer retina and segment them. The method is based on a model selection approach with special attention given to the balance bet...

从三维光学相干断层扫描数据中提取基于图像的生物标志物，例如某一层的存在、可见性或厚度，提供了相关的临床信息。我们提出了一种同时确定外层视网膜中可见层数量并进行分割的方法。该方法基于模型选择方法，特别关注平衡...

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

描述上述即将召开的会议活动。可能包括涵盖的主题或征稿通知。

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活动。可能包括涵盖的主题或征稿通知。

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

介绍本期出版物的目录。

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

描述了上述即将举行的会议活动。可能包括涵盖的主题或征稿通知。

Presents a listing of the editorial board, board of governors, current staff, committee members, and society editors for this issue of the publication.

介绍本期出版物的编辑委员会、理事会、现任工作人员、委员会成员和学会编辑名单。

These instructions give guidelines for preparing papers for this publication. Presents information for authors publishing in this journal.

这些指导方针为该刊物的论文准备提供了指南。为在本期刊发表论文的作者提供信息。