非酒精性肝脂肪病的早期檢測可以防止進一步的併發症如脂肪肝炎，脂肪纖維化到脂肪肝硬化。目前在檢測肝脂肪的含量，使用肝臟切片為診斷上的標準，但一般民眾接受肝臟穿刺檢查的意願不高，因此非侵入式的脂肪肝檢查診斷已成為重要的研究。核磁共振影像以及核磁共振頻譜，是一種目前非侵入式用來檢驗肝脂肪含量最好的方式。以往使用核磁共振頻譜來檢驗肝脂肪已有一定的發展，但是僅限於單點的量測，如今我們使用核磁共振頻譜影像，掃描時序列使用面質子迴訊磁共振頻譜影像方式收取資料，此脈衝序列可檢測肝脂肪含量的空間分佈，且在收取資料的時間上有很大的加速，完成一次收取資料只需要18秒，這個時間是在一般人可以閉氣的範圍內達成，在這裡我們進一步的調查T2弛緩效應的影響。我們使用迴訊磁共振頻譜影像量取不同TE的資料，並重覆掃描八次，觀察T2校正的重複性，我們的結果顯示，在測量脂肪含量是有很高的重現性，但因為肝臟脂肪有很大的T2弛緩時間變動範圍，若沒有考慮T2校正，在定量肝脂肪上會有很大的誤差，因此在定量肝脂肪含量上說明了T2校正的重要性。

Early detection of non-alcoholic fatty liver disease (NAFLD) can prevent further complications such as steatohepatitis, fibrosis and cirrhosis. Currently quantification of liver fat content relies on liver biopsy which is highly invasive method is still the gold standard for the evaluation of hepatic steatosis, but invasive method had a lot of disadvantages. Noninvasive study will become important. For noninvasive, magnetic resonance spectroscopy (MRS) and magnetic resonance imaging (MRI) are the good methods in lipid content test. There had a lot of outstanding research in MRS, But there focused in single voxel spectroscopy (SVS). In previous study, we used a fast magnetic resonance spectroscopic imaging (MRSI) techniques, acquisition sequence is proton echo-planar spectroscopic imaging (PEPSI) to measure lipid fat content. PEPSI is able to detect spatial distribution, and this is a fast acquisition sequence. In this thesis, we further investigated the influence of T2 relaxation effects. PEPSI scans with different TE were repeated 8 times to observe the reproducibility of T2 correction. Our results showed that the measured fat content is highly reproducible and the liver lipid T2 range is wide, so T2-correction is necessary in fat content quantified.

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