磁共振頻譜影像 (magnetic resonance spectroscopic image)，可能會受到強烈
的脂質訊號影響而產生吉布斯波紋假影，造成脂質汙染代謝物的頻譜，使代謝物
定量變得複雜。在二維磁共振頻譜影像中，常見的脂肪抑制方法是在腦部周圍的
皮下脂質位置擺置八條外部體積飽和帶(OVS) 或使用反轉恢復(inversion
recovery)來消除脂肪訊號。本研究使用基於空間信號投影的SSP後處理方法來達
到抑制脂肪的效果，SSP 透過提取脂質信號成分並加以去除，達到有效的脂質抑
制。本實驗在大腦仿體中實現抑制脂質的效果，透過平面回波頻譜影像(EPSI)收
取大腦仿體的數據，將SSP 脂質抑制後的代謝物濃度和大腦仿體中的已知濃度
比較，證明SSP 脂質抑制可以有效去除脂質汙染。SSP 脂質抑制方法可運用於三
維的磁共振頻譜影像上，可以有效抑制脂質且不會增加SAR 值的吸收，利於分
析全腦代謝物的頻譜。

Lipid contamination from the intense subcutaneous lipid signal that
produces Gibbs ringing artifacts may complicate the quantitation of metabolites in
the Magnetic Resonance Spectroscopic Image. In 2D MRSI, lipid suppression is
usually achieved by placing 8 outer volume saturation bands (OVS) around the
brain with subcutaneous lipids or use inversion recovery to eliminate fat signals. In this study, post-processing method based on spatial signal projection (SSP) was
used to achieve the effect of suppressing lipid signal. SSP extracts signal
components of lipids and removes them to achieve effective lipid suppression. In
this experiment, the effect of lipid suppressions was tested in brain phantoms. Data of brain phantom were collected by echo planar spectroscopic imaging (EPSI), and the concentration of metabolites after SSP lipid suppression was compared with the known concentration of brain phantom. The feasibility of SSP method for lipid
suppression was demonstrated.

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