Abstract:
PURPOSE:To develop and validate a method for choosing the optimal two-dimensional CAIPIRINHA kernel for subtraction contrast-enhanced MR angiography (CE-MRA) and estimate the degree of image quality improvement versus that of some reference acceleration parameter set at R ≥ 8. METHODS:A metric based on patient-specific coil calibration information was defined for evaluating optimality of CAIPIRINHA kernels as applied to subtraction CE-MRA. Evaluation in retrospective studies using archived coil calibration data from abdomen, calf, foot, and hand CE-MRA exams was accomplished with an evaluation metric comparing the geometry factor (g-factor) histograms. Prospective calf, foot, and hand CE-MRA studies were evaluated with vessel signal-to-noise ratio (SNR). RESULTS:Retrospective studies show g-factor improvement for the selected CAIPIRINHA kernels was significant in the feet, moderate in the abdomen, and modest in the calves and hands. Prospective CE-MRA studies using optimal CAIPIRINHA show reduced noise amplification with identical acquisition time in studies of the feet, with minor improvements in the hands and calves. CONCLUSION:A method for selection of the optimal CAIPIRINHA kernel for high (R ≥ 8) acceleration CE-MRA exams given a specific patient and receiver array was demonstrated. CAIPIRINHA optimization appears valuable in accelerated CE-MRA of the feet and to a lesser extent in the abdomen.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Weavers PT,Borisch EA,Riederer SJdoi
10.1002/mrm.25366subject
Has Abstractpub_date
2015-06-01 00:00:00pages
2234-42issue
6eissn
0740-3194issn
1522-2594journal_volume
73pub_type
杂志文章abstract:PURPOSE:To enable highly accelerated distortion-free MRI near metal by separating on- and off-resonance to exploit the redundancy of slice-phase encoding for the dominant on-resonance component. METHODS:Multispectral MRI techniques resolve off-resonance distortions by a combination of limited excitation bins and addit...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.26819
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abstract::The purpose of this study was to demonstrate the feasibility of dynamic oxygen-enhanced MRI in a clinical setting. We hypothesized that dynamic oxygen enhancement can reflect the regional diffusing capacity of the lung. Ten patients with pulmonary emphysema and seven healthy volunteers were examined with a respiratory...
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journal_title:Magnetic resonance in medicine
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abstract::Phased-array coils distribute the high signal-to-noise ratio (SNR) performance of their small component surface coils over the larger area covered by the entire array. The inhomogeneous sensitivity profiles of the component surface coils result in images with very high signal near the phased-array and decreased signal...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910350419
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abstract::The success in utilizing in vivo NMR to identify and/or monitor metabolic abnormalities will be determined in large part on the reliability with which the spectral parameters of the metabolites present can be measured. For these reasons it is clear that there is a need for the development of algorithms with which to o...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910100306
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journal_title:Magnetic resonance in medicine
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abstract::A new NMR imaging technique, aiming at a reduction of the data acquisition time, is described in detail. The method is applicable in all multidimensional imaging situations where at least one spatial coordinate is resolved. Discussed at some length are the point-spread function, the required bandwidth of the NMR spect...
journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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abstract::A demonstration of MR guided thermal surgery involved experiments with imaging of focused ultrasound in an MRI system, measurements of the thermal transients and a thermal analysis of the resulting images. Both the heat distribution and the creation of focused ultrasound lesions in gel phantoms, in vitro bovine muscle...
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journal_title:Magnetic resonance in medicine
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更新日期:2002-08-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2012-10-01 00:00:00
abstract:PURPOSE:The T(1) of tissue has a strong dependence on the measurement magnetic field strength. T(1) -dispersion could be a useful contrast parameter, but is unavailable to clinical MR systems which operate at fixed magnetic field strength. The purpose of this work was to implement a removable insert magnet coil for fie...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.25040
更新日期:2014-11-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2008-05-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/(sici)1522-2594(200005)43:5<657::aid-mrm7>
更新日期:2000-05-01 00:00:00
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更新日期:2020-12-08 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/(sici)1522-2594(199912)42:6<1089::aid-mrm1
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journal_title:Magnetic resonance in medicine
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更新日期:2013-10-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:1994-07-01 00:00:00
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更新日期:2019-03-01 00:00:00
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更新日期:2015-08-01 00:00:00
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更新日期:2003-04-01 00:00:00
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更新日期:2006-07-01 00:00:00