Volume 33, Issue 8

Object tracking is a key enabling technology in the context of computer-assisted medical interventions. Allowing the continuous localization of medical instruments and patient anatomy, it is a prerequisite for providing instrument guidance to subsurface anatomical structures. The only widely used technique that enables real-time tracking of small objects without line-of-sight restrictions is electromagnetic (EM) tracking. While EM tracking has been the subject of many research efforts, clinical applications have been slow to emerge. The aim of this review paper is therefore to provide insight into the future potential and limitations of EM tracking for medical use. We describe the basic working principles of EM tracking systems, list the main sources of error, and summarize the published studies on tracking accuracy, precision and robustness along with the corresponding validation protocols proposed. State-of-the-art approaches to error compensation are also reviewed in depth. Finally, an overview of the clinical applications addressed with EM tracking is given. Throughout the paper, we report not only on scientific progress, but also provide a review on commercial systems. Given the continuous debate on the applicability of EM tracking in medicine, this paper provides a timely overview of the state-of-the-art in the field.

对象追踪是计算机辅助医学干预中的一项关键使能技术。通过连续定位医疗器械和患者解剖结构，它为深层解剖结构提供器械引导的前提条件。唯一广泛使用的、无需视线限制即可实时追踪小物体的技术是电磁（EM）追踪。尽管电磁追踪已成为许多研究的主题，但临床应用进展缓慢。因此，本综述旨在深入了解电磁追踪在医学中的未来潜力和局限性。我们描述了电磁追踪系统的基本工作原理，列出了主要误差来源，并总结了已发表的关于追踪精度、准确性和鲁棒性的研究以及相应的验证协议。此外，还深入综述了最新的误差补偿方法。最后，概述了电磁追踪所涉及的临床应用。全文不仅报告了科学进展，还对商业系统进行了综述。鉴于关于电磁追踪在医学中适用性的持续争论，本文及时概述了该领域的最新进展。

Spectral computed tomography (CT) provides information on material characterization and quantification because of its ability to separate different basis materials. Dual-energy (DE) CT provides two sets of measurements at two different source energies. In principle, two materials can be accurately decomposed from DECT measurements. However, many clinical and industrial applications require three o...

能谱计算机断层扫描（CT）因其分离不同基础材料的能力，提供了材料表征和定量信息。双能量（DE）CT在两个不同的源能量下提供两组测量值。原则上，可以从DECT测量中准确分解两种材料。然而，许多临床和工业应用需要三...

Respiration-correlated CBCT, commonly called 4DCBCT, provides respiratory phase-resolved CBCT images. A typical 4DCBCT represents averaged patient images over one breathing cycle and the fourth dimension is actually breathing phase instead of time. In many clinical applications, it is desirable to obtain true 4DCBCT with the fourth dimension being time, i.e., each constituent CBCT image correspond...

呼吸相关CBCT，通常称为4DCBCT，提供呼吸相位分辨的CBCT图像。典型的4DCBCT表示一个呼吸周期内患者图像的平均，第四维度实际上是呼吸相位而非时间。在许多临床应用中，希望获得第四维度为时间的真实4DCBCT，即每个组成CBCT图像对应...

Dynamic magnetic resonance imaging (MRI) is used in multiple clinical applications, but can still benefit from higher spatial or temporal resolution. A dynamic MR image reconstruction method from partial ( k, t)-space measurements is introduced that recovers and inherently separates the information in the dynamic scene. The reconstruction model is based on a low-rank plus sparse decomposition prio...

动态磁共振成像（MRI）用于多种临床应用，但仍可从更高的空间或时间分辨率中受益。本文介绍了一种基于部分(k,t)空间测量的动态MR图像重建方法，该方法恢复并固有地分离动态场景中的信息。重建模型基于低秩加稀疏分解先验...

Dynamic contrast enhanced MRI (DCE-MRI) provides insight into the vascular properties of tissue. Pharmacokinetic models may be fitted to DCE-MRI uptake patterns, enabling biologically relevant interpretations. The aim of our study was to determine whether treatment outcome for 81 patients with locally advanced cervical cancer could be predicted from parameters of the Brix pharmacokinetic model der...

动态对比增强MRI（DCE-MRI）可提供组织血管特性的信息。药代动力学模型可拟合DCE-MRI的摄取模式，从而实现生物学相关解释。我们的研究目的是确定是否可以根据Brix药代动力学模型的参数预测81例局部晚期宫颈癌患者的治疗结果。

The development of spectral X-ray computed tomography (CT) using binned photon-counting detectors has received great attention in recent years and has enabled selective imaging of contrast agents loaded with K-edge materials. A practical issue in implementing this technique is the mitigation of the high-noise levels often present in material-decomposed sinogram data. In this work, the spectral X-r...

使用分档光子计数探测器的光谱X射线计算机断层扫描（CT）的发展近年来受到了广泛关注，并实现了对加载有K-edge材料的造影剂的选择性成像。实施该技术的一个实际问题是如何减轻材料分解正弦图数据中常见的高噪声水平。在这项工作中，光谱X射线...

We describe a framework to model visual semantics of liver lesions in CT images in order to predict the visual semantic terms (VST) reported by radiologists in describing these lesions. Computational models of VST are learned from image data using linear combinations of high-order steerable Riesz wavelets and support vector machines (SVM). In a first step, these models are used to predict the pres...

我们描述了一个框架，用于对CT图像中的肝脏病灶的视觉语义进行建模，以预测放射科医生在描述这些病灶时报告的视觉语义术语（VST）。VST的计算模型是通过使用高阶可操纵Riesz小波和支持向量机（SVM）的线性组合从图像数据中学习的。第一步，这些模型用于预测...

The purpose of this work is to correct for transient gradient waveform errors in magnetic resonance imaging (MRI), whether from eddy currents, group delay, or gradient amplifier nonlinearities, which are known to affect image quality. An iterative method is proposed to minimize error between desired and measured gradient waveforms, whose success does not depend on accurate knowledge of the gradien...

本工作的目的是校正磁共振成像（MRI）中的瞬态梯度波形误差，这些误差可能来自涡流、群延迟或梯度放大器非线性，已知会影响图像质量。提出了一种迭代方法，以最小化期望梯度波形与测量梯度波形之间的误差，其成功不依赖于对梯度系统瞬态响应的精确了解。

Registration of histological slices to volumetric imaging of the prostate is an important task that can be used to optimize imaging for cancer detection. Such registration is challenging due to physical changes of the specimen during excision and fixation, and misalignment of the histological slices during preparation and digital scanning. In this work, we consider a multi-slice to volume registra...

将组织切片与前列腺体积成像配准是一项重要任务，可用于优化癌症检测的成像。由于切除和固定过程中标本的物理变化，以及制备和数字扫描过程中组织切片的错位，这种配准具有挑战性。在这项工作中，我们考虑了一种多切片到体积的配准...

In image-guided radiotherapy (IGRT) of disease sites subject to respiratory motion, soft tissue deformations can affect localization accuracy. We describe the application of a method of 2D/3D deformable registration to soft tissue localization in abdomen. The method, called registration efficiency and accuracy through learning a metric on shape (REALMS), is designed to support real-time IGRT. In a...

在受呼吸运动影响的疾病部位的图像引导放疗（IGRT）中，软组织变形会影响定位精度。我们描述了一种2D/3D可变形配准方法在腹部软组织定位中的应用。该方法称为通过学习形状度量实现配准效率和准确性（REALMS），旨在支持实时IGRT。

This paper presents an algorithm for 3-D reconstruction of tumor ablations using ultrasound shear wave imaging with electrode vibration elastography. Radio-frequency ultrasound data frames are acquired over imaging planes that form a subset of a sheaf of planes sharing a common axis of intersection. Shear wave velocity is estimated separately on each imaging plane using a piecewise linear function...

本文提出了一种利用超声剪切波成像与电极振动弹性成像对肿瘤消融进行三维重建的算法。在共享一个公共相交轴的平面束子集上获取射频超声数据帧。使用分段线性函数在每个成像平面上分别估计剪切波速度...

Magnetic resonance imaging (MRI) is widely used to study population effects of factors on brain morphometry. Inference from such studies often require the simultaneous testing of millions of statistical hypotheses. Such scale of inference is known to lead to large numbers of false positive results. Control of the false discovery rate (FDR) is commonly employed to mitigate against such outcomes. Ho...

磁共振成像（MRI）被广泛用于研究因素对大脑形态测量的人群效应。此类研究的推断通常需要同时测试数百万个统计假设。已知这种规模的推断会导致大量的假阳性结果。错误发现率（FDR）控制通常用于减轻此类结果的影响。...

In this paper, we propose a new bootstrap scheme, called the nonlocal bootstrap (NLB) for uncertainty estimation. In contrast to the residual bootstrap, which relies on a data model, or the repetition bootstrap, which requires repeated signal measurements, NLB is not restricted by the data structure imposed by a data model and obviates the need for time-consuming multiple acquisitions. NLB hinges ...

在本文中，我们提出了一种新的自举方案，称为非局部自举法（NLB），用于不确定性估计。与依赖于数据模型的残差自举法或需要重复信号测量的重复自举法不同，NLB不受数据模型所施加的数据结构限制，并且避免了耗时的多次采集。NLB基于...

Optical mapping has become a common tool for cardiovascular research, providing high resolution spatiotemporal data of cardiac action potential propagation. However, noise in cardiac optical mapping (COM) data hampers quantitative measurements and analyses. Spatial and temporal filters have been used to increase the signal-to-noise ratio (SNR) of COM data. Although these help reduce noise and incr...

光学映射已成为心血管研究的常用工具，提供心脏动作电位传播的高分辨率时空数据。然而，心脏光学映射（COM）数据中的噪声阻碍了定量测量和分析。空间和时间滤波器已被用于提高COM数据的信噪比（SNR）。尽管这些方法有助于减少噪声和增加...

Transmit arrays have been developed to mitigate the RF field inhomogeneity commonly observed in high field magnetic resonance imaging (MRI), typically above 3T. To this end, the knowledge of the RF complex-valued B1 transmit-sensitivities of each independent radiating element has become essential. This paper details a method to speed up a currently available B1-calibration method. The principle re...

发射阵列已被开发用于减轻高场磁共振成像（MRI）中常见的射频场不均匀性，通常高于3T。为此，了解每个独立辐射元件的射频复数B1发射灵敏度变得至关重要。本文详细介绍了一种加速当前可用B1校准方法的技术。原理是...

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。

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

提供当前工作人员、委员会成员和学会官员列表。

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

呈现本期期刊的目录。

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

为有意投稿的作者提供说明和指南。