Abstract：
:Motivated by the observation that the diagonal pattern of intensity nonuniformity usually associated with linearly polarized radio-frequency (RF) coils is often present in neurological scans using circularly polarized coils, a theoretical analysis has been conducted of the intensity nonuniformity inherent in imaging an elliptically shaped object using 1.5-T magnets and circularly polarized RF coils. This first principle analysis clarifies, for the general case of conducting objects, the relationship between the excitation field and the reception sensitivity of circularly and linearly polarized coils. The results, validated experimentally using a standard spin-echo imaging sequence and an in vivo B1 field mapping technique, are shown to be accurate to within 1%-2% root mean square, suggesting that these electromagnetic interactions with the object account for most of the intensity nonuniformity observed.
journal_name
IEEE Trans Med Imagingjournal_title
IEEE transactions on medical imagingauthors
Sled JG,Pike GBdoi
10.1109/42.730409subject
Has Abstractpub_date
1998-08-01 00:00:00pages
653-62issue
4eissn
0278-0062issn
1558-254Xjournal_volume
17pub_type
杂志文章abstract：:The National Library of Medicine (NLM) is developing a digital chest X-ray (CXR) screening system for deployment in resource constrained communities and developing countries worldwide with a focus on early detection of tuberculosis. A critical component in the computer-aided diagnosis of digital CXRs is the automatic ...
journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2013.2290491
更新日期：2014-02-01 00:00:00
abstract：:Epilepsy is a neurological disorder characterized by sudden and unpredictable epileptic seizures, which incurs significant negative impacts on patients' physical, psychological and social health. A practical approach to assist with the clinical assessment and treatment planning for patients is to process magnetoenceph...
journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2019.2958699
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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：:Risk stratification (characterization) of tumors from radiology images can be more accurate and faster with computer-aided diagnosis (CAD) tools. Tumor characterization through such tools can also enable non-invasive cancer staging, prognosis, and foster personalized treatment planning as a part of precision medicine....
journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2019.2894349
更新日期：2019-08-01 00:00:00
abstract：:In this paper, we propose a novel method for the registration of volumetric images of the brain that optimizes the alignment of both cortical and subcortical structures. In order to achieve this, relevant geometrical information is extracted from a surface-based morph and diffused into the volume using the Navier oper...
journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2008.2004426
更新日期：2009-04-01 00:00:00
abstract：:This paper discusses image reconstruction with a tilted gantry in multislice computed tomography (CT) with helical (spiral) data acquisition. The reconstruction problem with gantry tilt is shown to be transformable into the problem of reconstructing a virtual object from multislice CT data with no gantry tilt, for whi...
journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2004.829337
更新日期：2004-09-01 00:00:00
abstract：:Accurate gain control of PET detectors is a prerequisite for quantitative accuracy. A shift in the 511 keV peak position can lead to errors in scatter correction, degrading quantitation. The PET detectors in a PET/MR scanner are subject to thermal transients due to eddy currents induced during gradient-intensive MRI s...
journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2020.3022321
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journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2004.824234
更新日期：2004-03-01 00:00:00
abstract：:A method for detection and removal of random spike noise in magnetic resonance (MR) raw data (k-space data) is described. This method would reduce or eliminate the corduroy-type and higher than usual level artifacts in MR images resulting from random spike noise in k-space data. The method described involves applying ...
journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/42.276151
更新日期：1994-01-01 00:00:00
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journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2019.2937458
更新日期：2020-04-01 00:00:00
abstract：:Complete projection (360 degrees ) free-space fluorescence tomography of opaque media is poised to enable 3-D imaging through entire small animals in vivo with improved depth resolution compared to 360 degrees -projection fiber-based systems or limited-view angle systems. This approach can lead to a new generation of ...
journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2007.904662
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journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2020.2998480
更新日期：2020-11-01 00:00:00
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journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/42.97578
更新日期：1991-01-01 00:00:00
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journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/42.925294
更新日期：2001-05-01 00:00:00
abstract：:We propose a method that incorporates the time-frequency characteristics of neural sources into magnetoencephalographic (MEG) source estimation. The method is based on the multiple-signal-classification (MUSIC) algorithm and it calculates a time--frequency matrix in which diagonal and off-diagonal terms are the auto a...
journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/42.750262
更新日期：1999-01-01 00:00:00
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journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2019.2953974
更新日期：2020-05-01 00:00:00
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journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2020.2990823
更新日期：2020-11-01 00:00:00
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journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2016.2636188
更新日期：2017-03-01 00:00:00
abstract：:Cerebral ischemic stroke causes injury to brain tissue characterized by a complex cascade of neuronal and vascular events. Imaging during the early stages of its development allows prediction of tissue infarction and penumbra so that optimal intervention can be determined in order to salvage brain function impairment....
journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2019.2895779
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journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2011.2125980
更新日期：2011-08-01 00:00:00
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journal_title：IEEE transactions on medical imaging
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doi：10.1109/TMI.2021.3052972
更新日期：2021-01-20 00:00:00
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journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.1983.4307617
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journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2020.3008871
更新日期：2020-12-01 00:00:00
abstract：:A reconstruction algorithm to simultaneously estimate the shape and location of three-dimensional breast cancer tumor is presented and its utility is analyzed. The approach is based on a spherical harmonic decomposition to capture the shape of the tumor. We combine a gradient descent optimization method with a direct ...
journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/tmi.2006.881377
更新日期：2006-10-01 00:00:00
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journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2017.2750210
更新日期：2018-01-01 00:00:00
abstract：:An overview of the Shinnar-Le Roux (SLR) algorithm is presented. It is shown how the performance of SLR pulses can be very accurately specified analytically. This reveals how to design a pulse that produces a specified slice profile and allows the pulse designer to trade off analytically the parameters describing the ...
journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/42.75611
更新日期：1991-01-01 00:00:00
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journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2020.3004511
更新日期：2020-11-01 00:00:00
abstract：:In this paper, we propose a new prostate computed tomography (CT) segmentation method for image guided radiation therapy. The main contributions of our method lie in the following aspects. 1) Instead of using voxel intensity information alone, patch-based representation in the discriminative feature space with logisti...
journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2012.2230018
更新日期：2013-02-01 00:00:00
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journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2008.918326
更新日期：2008-10-01 00:00:00
abstract：:Respiratory signals are required for image gating and motion compensation in minimally invasive interventions. In X-ray fluoroscopy, extraction of a respiratory signal can be challenging due to characteristics of interventional imaging, in particular injection of contrast agent and automatic exposure control. We prese...
journal_title：IEEE transactions on medical imaging
pub_type： 杂志文章
doi：10.1109/TMI.2016.2609888
更新日期：2017-04-01 00:00:00
