非酒精性脂肪肝(NAFLD)在已開發國家中是一個很常見的肝臟疾病，為了預防加重成肝纖維化或肝硬化，早期偵測是否有非酒精脂肪肝變得很重要。之前我們使用快速磁振頻譜影像技術(PEPSI)來取得肝臟脂肪含量，對於16x32 的空間解析度只需要18 秒，而且時間夠短可以要求受試者閉氣，並且證實具有足夠的準確性。現在我們想要進一步提高空間解析度到24x32，並且掃描時間能維持跟以前一樣。所以我們搭配上平行影像的技術來縮短掃描的時間，搭配上平行影像技術後，我們需要調查在取得脂肪含量的表現是否跟以往只使用快速磁振頻譜影像時一樣準確，我們將只使用快速頻譜影像的資料作為標準，比較於搭配上平行影像技術的資料，我們所用的平行影像技術為GRAPPA。結果顯示，水訊號的重建比起脂肪訊號是較穩定的，在脂肪含量的計算上，模擬加速比起實際加速是比較接近只使用快速磁振頻譜影技術。結論上，我們能確實利用平行影像技術來達到2 倍加速，只是在取得脂肪含量的表現上還需要更進一步的改進。

Non-alcoholic fatty liver disease (NAFLD) is a common liver disease in developed country, for preventing it develop to further complications such as fibrosis and cirrhosis, early detection of NAFLD becomes very important. In the past, we use proton echo planar spectroscopic imaging (PEPSI) to acquire the hepatic fat content (HFC) and PEPSI is proved that it is able to acquire the HFC accurately. For matrix size 16x32 the scan time is 18 seconds, and the scan time is short enough to ask the subject to hold his breath. Now, we want to further the matrix size to 24x32 and the scan time can be as short as before. So, we combine PEPSI and parallel imaging technology to shorten scan time. We want to investigate the performance of PEPSI with parallel imaging to see if it has the same accuracy as PEPSI. We set full-sampled PEPSI as the standard, compared with PEPSI with parallel imaging. One of the parallel imaging technology, generalized autocalibrating partially parallel acquisitions (GRAPPA) is enrolled. The results showed that the reconstruction of water signal is more stable than lipid signal. Simulated GRAPPA is more close to full-sampled PEPSI than real GRAPPA on quantifying HFC. In conclusion, 2-fold accelerated PEPSI is implemented successfully but the performance need further improvement.

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