9.4T 자기공명분광분석의 지질 양성자 (Lipid proton)의 T2 교정을 통한 지방 퍼센티지 정량화 연구: 팬텀 연구 = A Study of Lipid Percentage Quantification through T2 Correction of Lipid Proton in 9.4T Magnetic Resonance Spectroscopy: Phantom Study

다국어 초록 (Multilingual Abstract)

The T2 relaxation time of each lipid proton in 9.4T MRS is calculated to evaluate theerror between the T2 corrected lipid percentage and the T2 corrected lipid percentage, and it isintended to reveal the optimal TE in the MRS test conditions between 9.4T without T2 correction.
Lipid phantom was made to have a lipid ratio of 10%. The phantom MRS data was acquired by9.4T laboratory animal MRI and mouse surface coil, and the parameters was applied as following: time to repeat (TR) is 5,000 msec, time of echo (TE) is 7, 10, 15, 20, 30, 50, 70, 100 msec. Themeasured LP data include methyl protons (-CH3); 0.90 ppm) and six LP signals were analyzedusing LCModel software (version 6.3-1H, Stephen W. Provencher), and the data of LP was useda standard deviation (% SD) of less than 10%, which was a useful reliability indicator. The resultof T2* corrected M0 was calculated by T2 relaxation curve mono exponential graph fitting.
The T2 relaxation time of LP had different patterns. LP showing the shortest T2 was methaneprotons (-CH=CH-; 5.3 ppm), and the LP showing the longest T2 was methyl protons (-CH3);0.90 ppm).The percentage of LP obtained by performing the T2* correction was 13.476%, andthe lipid percentage with the lowest error at TE 30 msec was shown. In an environment wheremulti TE cannot be applied when performing 9.4T liver experiments, it is recommended to setthe relevant conditions to obtain data because when data is acquired by setting TE to 30 msec, anapproximation of the data corrected for T2 can be obtained.

참고문헌 (Reference)

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