Abstract：
PURPOSE:Visual review of individual spectra in magnetic resonance spectroscopic imaging (MRSI) data benefits from the application of spectral smoothing; however, if this processing step is applied prior to spectral analysis this can impact the accuracy of the quantitation. This study aims to analyze the effect of spectral denoising and apodization smoothing on the quantitation of whole-brain MRSI data obtained at short TE. METHODS:Short-TE MRSI data obtained at 3 T were analyzed with no spectral smoothing, following (i) Gaussian apodization with values of 1, 2, 4, 6, and 8 Hz, and (ii) denoising using principal component analysis (dnPCA) with 3 different values for the number of retained principal components. The mean lobar white matter estimates for four metabolites, signal-to-noise ratio (SNR), spectral linewidth, and confidence intervals were compared to data reconstructed using no smoothing. Additionally, a voxel-wise comparison for N-acetylaspartate quantitation with different smoothing schemes was performed. RESULTS:Significant pairwise differences were seen for all Gaussian smoothing methods as compared to no smoothing (p<0.001) in linewidth and metabolite estimates, whereas dnPCA methods showing no statistically significant differences in these measures. Confidence intervals decreased, and SNR increased with increasing levels of apodization smoothing or dnPCA denoising. CONCLUSION:Mild Gaussian apodization (≤2 Hz at 3 T) can be applied with minimal (1%) errors in quantitation; however, smoothing values greater than that can significantly affect metabolite quantification. In contrast, mild to moderate dnPCA based denoising provides quantitative results that are consistent with the analysis of unsmoothed data and this method is recommended for spectral denoising.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Goryawala M,Sullivan M,Maudsley AAdoi
10.1016/j.mri.2020.04.013subject
Has Abstractpub_date
2020-07-01 00:00:00pages
108-114eissn
0730-725Xissn
1873-5894pii
S0730-725X(19)30555-7journal_volume
70pub_type
杂志文章abstract：:Magnetic resonance microscopy of skin from hairless rats under the influence of electrical fields was conducted for two cases: 1) low voltage constant electrical fields and 2) high-voltage short pulse, electrical fields. Under conditions of the low voltage and low current iontophoresis, i.e., 0 to 20 V, and 0 to 0.5 m...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(99)00067-3
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journal_title：Magnetic resonance imaging
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(87)90023-3
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2007.06.003
更新日期：2008-02-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2004.11.027
更新日期：2005-02-01 00:00:00
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pub_type： 杂志文章
doi：10.1016/0730-725x(94)92360-4
更新日期：1994-01-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2008.07.004
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(88)90398-0
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
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pub_type： 杂志文章
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(98)00043-5
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journal_title：Magnetic resonance imaging
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doi：10.1016/j.mri.2014.02.007
更新日期：2014-07-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
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更新日期：2003-01-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2015.08.003
更新日期：2015-12-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
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pub_type： 杂志文章
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章,评审
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更新日期：1992-01-01 00:00:00
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更新日期：2000-06-01 00:00:00
