Abstract:
:The maximum likelihood (ML) approach to estimating the radioactive distribution in the body cross section has become very popular among researchers in emission computed tomography (ECT) since it has been shown to provide very good images compared to those produced with the conventional filtered backprojection (FBP) algorithm. The expectation maximization (EM) algorithm is an often-used iterative approach for maximizing the Poisson likelihood in ECT because of its attractive theoretical and practical properties. Its major disadvantage is that, due to its slow rate of convergence, a large amount of computation is often required to achieve an acceptable image. Here, the authors present a row-action maximum likelihood algorithm (RAMLA) as an alternative to the EM algorithm for maximizing the Poisson likelihood in ECT. The authors deduce the convergence properties of this algorithm and demonstrate by way of computer simulations that the early iterates of RAMLA increase the Poisson likelihood in ECT at an order of magnitude faster that the standard EM algorithm. Specifically, the authors show that, from the point of view of measuring total radionuclide uptake in simulated brain phantoms, iterations 1, 2, 3, and 4 of RAMLA perform at least as well as iterations 45, 60, 70, and 80, respectively, of EM. Moreover, the authors show that iterations 1, 2, 3, and 4 of RAMLA achieve comparable likelihood values as iterations 45, 60, 70, and 80, respectively, of EM. The authors also present a modified version of a recent fast ordered subsets EM (OS-EM) algorithm and show that RAMLA is a special case of this modified OS-EM. Furthermore, the authors show that their modification converges to a ML solution whereas the standard OS-EM does not.
journal_name
IEEE Trans Med Imagingjournal_title
IEEE transactions on medical imagingauthors
Browne J,de Pierro ABdoi
10.1109/42.538946subject
Has Abstractpub_date
1996-01-01 00:00:00pages
687-99issue
5eissn
0278-0062issn
1558-254Xjournal_volume
15pub_type
杂志文章abstract::The effects of Squashing, an algorithm introduced by J.A. Reeds and L.A. Shepp (see ibid., vol.MI-6, no.2, p.89-97, June 1987), are described. It is proven that Squashing induces a weight function upon the projections. Intuitive and numerical evidence is presented showing that this weight function is not desirable at ...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/42.57761
更新日期:1990-01-01 00:00:00
abstract::The expectation maximization method for maximum likelihood image reconstruction in emission tomography, based on the Poisson distribution of the statistically independent components of the image and measurement vectors, is extended to a maximum aposteriori image reconstruction using a multivariate Gaussian a priori pr...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.1987.4307826
更新日期:1987-01-01 00:00:00
abstract::The aim of this study was to provide mathematical descriptors for the border of pigmented skin lesion images and to assess their efficacy for distinction among different lesion groups. New descriptors such as lesion slope and lesion slope regularity are introduced and mathematically defined. A new algorithm based on t...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2003.815901
更新日期:2003-08-01 00:00:00
abstract::The Bayesian ideal observer provides an absolute upper bound for diagnostic performance of an imaging system and hence should be used for the assessment of image quality whenever possible. However, computation of ideal-observer performance in clinical tasks is difficult since the probability density functions of the d...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2008.2008967
更新日期:2009-05-01 00:00:00
abstract::A common method of increasing hemodynamic response (SNR) in functional magnetic resonance imaging (fMRI) is to average signal timecourses across voxels. This technique is potentially problematic because the hemodynamic response may vary across the brain. Such averaging may destroy significant features in the temporal ...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2003.819922
更新日期:2004-01-01 00:00:00
abstract::Magnetic resonance imaging (MRI) pulse sequence consoles typically employ closed proprietary hardware, software, and interfaces, making difficult any adaptation for innovative experimental technology. Yet MRI systems research is trending to higher channel count receivers, transmitters, gradient/shims, and unique inter...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2011.2169681
更新日期:2012-02-01 00:00:00
abstract::The hybrid magnetic resonance (MR)/X-ray suite (XMR) is a recently introduced imaging solution that provides new possibilities for guidance of cardiovascular catheterization procedures. We have previously described and validated a technique based on optical tracking to register MR and X-ray images obtained from the sl...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2005.856731
更新日期:2005-11-01 00:00:00
abstract::The ordinary sample correlation coefficient is a popular similarity measure for aligning images from the same or similar modalities. However, this measure can be sensitive to the presence of "outlier" objects that appear in one image but not the other, such as surgical instruments, the patient table, etc., which can l...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2004.835313
更新日期:2004-11-01 00:00:00
abstract::Measures of vascular tortuosity-how curved and twisted a vessel is-are associated with a variety of vascular diseases. Consequently, measurements of vessel tortuosity that are accurate and comparable across modality, resolution, and size are greatly needed. Yet in practice, precise and consistent measurements are prob...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2020.3025467
更新日期:2021-01-01 00:00:00
abstract::For certain medical applications resampling of data is required. In magnetic resonance tomography (MRT) or computer tomography (CT), e.g., data may be sampled on nonrectilinear grids in the Fourier domain. For the image reconstruction a convolution-interpolation algorithm, often called gridding, can be applied for res...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/42.774166
更新日期:1999-05-01 00:00:00
abstract::Muscle coordination patterns of lingual behaviors are synergies generated by deforming local muscle groups in a variety of ways. Functional units are functional muscle groups of local structural elements within the tongue that compress, expand, and move in a cohesive and consistent manner. Identifying the functional u...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2018.2870939
更新日期:2019-03-01 00:00:00
abstract::Direct reconstruction of kinetic parameters from raw projection data is a challenging task in molecular imaging using dynamic positron emission tomography (PET). This paper presents a new optimization transfer algorithm for penalized likelihood direct reconstruction of nonlinear parametric images that is easy to use a...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2012.2212203
更新日期:2012-10-01 00:00:00
abstract::The feasibility of ultrasonic Nakagami imaging to evaluate thermal lesions by high-intensity focused ultrasound and microwave ablation was explored in ex vivo and in vivo liver models. Dynamic changes of the ultrasonic Nakagami parameter in thermal lesions were calculated, and ultrasonic B-mode and Nakagami images wer...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2018.2829934
更新日期:2018-07-01 00:00:00
abstract::In this paper, we formulate a reconstruction algorithm for an n-Pi acquisition, where n can be any positive odd integer. The algorithm is a generalization of the method presented in (Bontus et al. 2003). It is based on the results obtained by Katsevich (2004). For the algorithm, different sets of filter-lines have to ...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2005.850545
更新日期:2005-08-01 00:00:00
abstract::Photon counting computed tomography (PCCT) has the ability to identify individual photons, resulting in quantitative material identification. Meanwhile, several technical challenges still exist in current PCCT imaging systems, including increased noise and suboptimal bin selection. These nonideal effects can substanti...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2020.3001616
更新日期:2020-11-01 00:00:00
abstract::Synthetic phased array (SPA) beamforming with Hadamard coding and aperture weighting is an optimal option for real-time volumetric imaging with a ring array, a particularly attractive geometry in intracardiac and intravascular applications. However, the imaging frame rate of this method is limited by the immense compu...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2013.2253117
更新日期:2013-07-01 00:00:00
abstract::Diffuse Optical Tomography commonly neglects or assumes as insignificant the presence of optically clear regions in biological tissues, estimating their contribution as a small perturbation to light transport. The inaccuracy introduced by this practice is examined in detail in the context of a complete, based on reali...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2016.2646518
更新日期:2017-05-01 00:00:00
abstract::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 im...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2015.2427777
更新日期:2015-11-01 00:00:00
abstract::This paper presents a novel method for validation of nonrigid medical image registration. This method is based on the simulation of physically plausible, biomechanical tissue deformations using finite-element methods. Applying a range of displacements to finite-element models of different patient anatomies generates m...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2002.808367
更新日期:2003-02-01 00:00:00
abstract::While magnetic particle imaging (MPI) constitutes a novel biomedical imaging technique for tracking superparamagnetic nanoparticles in vivo, unlike magnetic resonance imaging (MRI), it cannot provide anatomical background information. Until now these two modalities have been performed in separate scanners and image co...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2014.2327515
更新日期:2014-10-01 00:00:00
abstract::Micro-computed tomography (micro-CT) has been widely used to generate high-resolution 3-D tissue images from small animals nondestructively, especially for mineralized skeletal tissues. However, its application to the analysis of soft cardiovascular tissues has been limited by poor inter-tissue contrast. Recent ex viv...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2012.2209183
更新日期:2013-01-01 00:00:00
abstract::3D Statistical Shape Models (3D-SSM) are widely used for medical image segmentation. However, during segmentation, they typically perform a very limited unidirectional search for suitable landmark positions in the image, relying on weak learners or use-case specific appearance models that solely take local image infor...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2016.2600502
更新日期:2017-01-01 00:00:00
abstract::With its single cell sensitivity over volumes as large as or larger than a mouse, cryo-imaging enables imaging of stem cell biodistribution, homing, engraftment, and molecular mechanisms. We developed and evaluated a highly automated software tool to detect fluorescently labeled stem cells within very large ( ∼ 200 GB...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2015.2497285
更新日期:2016-03-01 00:00:00
abstract::In this paper, we present a wavelet-based multigrid approach to solve the perturbation equation encountered in optical tomography. With this scheme, the unknown image, the data, as well as the weight matrix are all represented by wavelet expansions, thus yielding a multiresolution representation of the original pertur...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/42.563666
更新日期:1997-04-01 00:00:00
abstract::Displacement estimated interframe (DEI) coding, a coding scheme for 3-D medical image data sets such as X-ray computed tomography (CT) or magnetic resonance (MR) images, is presented. To take advantage of the correlation between contiguous slices, a displacement-compensated difference image based on the previous image...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/42.241875
更新日期:1993-01-01 00:00:00
abstract::Conventional ultrasound imaging is based on the scattering of sound from inhomogeneities in the density and the speed of sound and is often used in medicine to resolve pathologic compared to normal tissue. Here we demonstrate a difference-frequency ultrasound (dfUS) imaging method that is based on the interaction of t...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2019.2957280
更新日期:2020-05-01 00:00:00
abstract::A method that incorporates a priori uniform or nonuniform source distribution probabilistic information and data fluctuations of a Poisson nature is presented. The source distributions are modeled in terms of a priori source probability density functions. Maximum a posteriori probability solutions, as determined by a ...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/42.34711
更新日期:1989-01-01 00:00:00
abstract::Classical surgery is being overtaken by minimally invasive and transcatheter procedures. As there is no direct view or access to the affected anatomy, advanced imaging techniques such as 3D C-arm computed tomography (CT) and C-arm fluoroscopy are routinely used in clinical practice for intraoperative guidance. However...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2014.2343936
更新日期:2015-01-01 00:00:00
abstract::In this paper, discrepancies and reference inaccuracies in the paper (Grana et al., 2003) are pointed out. Specifically, it is demonstrated that the definitions of "lesion gradient" and "skin lesion gradient," widely used in a number of medical papers on computer analysis of pigmented skin lesions, are unambiguous, an...
journal_title:IEEE transactions on medical imaging
pub_type: 评论,信件
doi:10.1109/tmi.2006.884205
更新日期:2006-12-01 00:00:00
abstract::Diffuse optical tomography (DOT) is a noninvasive technique which measures hemodynamic changes in the tissue with near infrared light, which has been increasingly used to study brain functions. Due to the nature of light propagation in the tissue, the reconstruction problem is severely ill-posed. For linearized DOT pr...
journal_title:IEEE transactions on medical imaging
pub_type: 杂志文章
doi:10.1109/TMI.2014.2338214
更新日期:2014-12-01 00:00:00