SUFI63: Relaxation Times of Lipid Resonances in NAFLD Animal Model Using Enhanced Curve Fitting
Abstract
Purpose: The objective of this study is to evaluate the relaxation time of methylene resonance in comparison with other lipid resonances. Methods: The examinations were performed on a 3.0T MRI scanner using a fourchannel animal coil. Eight more SpragueDawley rats in the same baseline weight range were housed with ad libitum access to water and a highfat (HF) diet (60% fat, 20% protein, and 20% carbohydrate). In order to avoid large blood vessels, a voxel (0.8×0.8×0.8 cm{sup 3}) was placed in a homogeneous area of the liver parenchyma during free breathing. Lipid relaxations in NC and HF diet rats were estimated at a fixed repetition time (TR) of 6000 msec, and multi echo time (TEs) of 40–220 msec. All spectra for data measurement were processed using the Advanced Method for Accurate, Robust, and Efficient Spectral (AMARES) fitting algorithm of the Javabased Magnetic Resonance User Interface (jMRUI) package. Results: The mean T2 relaxation time of the methylene resonance in normalchow diet was 37.1 msec (M{sub 0}, 2.9±0.5), with a standard deviation of 4.3 msec. The mean T2 relaxation time of the methylene resonance was 31.4 msec (M{sub 0}, 3.7±0.3), with a standard deviation of 1.8 msec. The T2 relaxation times ofmore »
 Authors:
 Department of Biomedical Engineering, and Research Institute of Biomedical Engineering, The Catholic University of Korea College of Medicine, Seoul (Korea, Republic of)
 Publication Date:
 OSTI Identifier:
 22632126
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Medical Physics; Journal Volume: 43; Journal Issue: 6; Other Information: (c) 2016 American Association of Physicists in Medicine; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 60 APPLIED LIFE SCIENCES; ALGORITHMS; APPROXIMATIONS; BLOOD; BLOOD VESSELS; CARBOHYDRATES; DIET; HYDROFLUORIC ACID; LIPIDS; LIVER; NMR IMAGING; RATS; RELAXATION TIME
Citation Formats
Song, KH, Yoo, CH, Lim, SI, and Choe, BY. SUFI63: Relaxation Times of Lipid Resonances in NAFLD Animal Model Using Enhanced Curve Fitting. United States: N. p., 2016.
Web. doi:10.1118/1.4955891.
Song, KH, Yoo, CH, Lim, SI, & Choe, BY. SUFI63: Relaxation Times of Lipid Resonances in NAFLD Animal Model Using Enhanced Curve Fitting. United States. doi:10.1118/1.4955891.
Song, KH, Yoo, CH, Lim, SI, and Choe, BY. 2016.
"SUFI63: Relaxation Times of Lipid Resonances in NAFLD Animal Model Using Enhanced Curve Fitting". United States.
doi:10.1118/1.4955891.
@article{osti_22632126,
title = {SUFI63: Relaxation Times of Lipid Resonances in NAFLD Animal Model Using Enhanced Curve Fitting},
author = {Song, KH and Yoo, CH and Lim, SI and Choe, BY},
abstractNote = {Purpose: The objective of this study is to evaluate the relaxation time of methylene resonance in comparison with other lipid resonances. Methods: The examinations were performed on a 3.0T MRI scanner using a fourchannel animal coil. Eight more SpragueDawley rats in the same baseline weight range were housed with ad libitum access to water and a highfat (HF) diet (60% fat, 20% protein, and 20% carbohydrate). In order to avoid large blood vessels, a voxel (0.8×0.8×0.8 cm{sup 3}) was placed in a homogeneous area of the liver parenchyma during free breathing. Lipid relaxations in NC and HF diet rats were estimated at a fixed repetition time (TR) of 6000 msec, and multi echo time (TEs) of 40–220 msec. All spectra for data measurement were processed using the Advanced Method for Accurate, Robust, and Efficient Spectral (AMARES) fitting algorithm of the Javabased Magnetic Resonance User Interface (jMRUI) package. Results: The mean T2 relaxation time of the methylene resonance in normalchow diet was 37.1 msec (M{sub 0}, 2.9±0.5), with a standard deviation of 4.3 msec. The mean T2 relaxation time of the methylene resonance was 31.4 msec (M{sub 0}, 3.7±0.3), with a standard deviation of 1.8 msec. The T2 relaxation times of methylene protons were higher in normalchow diet rats than in HF rats (p<0.05), and the extrapolated M{sub 0} values were higher in HF rats than in NC rats (p<0.005). The excellent linear fit with R{sup 2}>0.9971 and R{sup 2}>0.9987 indicates T2 relaxation decay curves with monoexponential function. Conclusion: In in vivo, a sufficient spectral resolution and a sufficiently high signaltonoise ratio (SNR) can be achieved, so that the data measured over short TE values can be extrapolated back to TE = 0 to produce better estimates of the relative weights of the spectral components. In the short term, treating the effective decay rate as exponential is an adequate approximation.},
doi = {10.1118/1.4955891},
journal = {Medical Physics},
number = 6,
volume = 43,
place = {United States},
year = 2016,
month = 6
}

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