质子密度脂肪分数（proton density fat fraction，PDFF）是用于评估肝脏脂肪的重要定量指标.为了获得更为精确的肝脏PDFF，本文通过分离R2*估计，提出了一种改进的基于磁共振成像（magnetic resonance imaging，MRI）脂肪定量方法.通过在3.0 T MRI扫描仪器上对肝脏脂肪含量不同的人体被试进行MRI扫描，进一步验证了该方法的可行性和准确性.研究结果显示，本文方法得到的肝脏脂肪分数和磁共振波谱（magnetic resonance spectroscopy，MRS）分析得到的脂肪含量高度一致，表明该方法对临床脂肪肝的检测具有重要的参考指导价值.
翟国强
,
张苗
,
薄斌仕
,
王乙
,
范明霞
,
李建奇
. 基于复值和模值的肝脏磁共振水脂分离组合算法[J]. 波谱学杂志, 2018
, 35(4)
: 417
-426
.
DOI: 10.11938/cjmr20182635
Proton density fat fraction (PDFF) is emerging as a useful quantitative magnetic resonance imaging (MRI) biomarker for the diagnosis of hepatic steatosis. In this work, a hybrid method combining complex-based and magnitude-based water-fat separation was proposed to provide accurate measurements of liver PDFF. Clinical experiments were performed to evaluate the feasibility and accuracy of the method proposed. The results demonstrated that PDFF results obtained with the proposed method had excellent correlation and agreement with those calculated from magnetic resonance spectroscopy (MRS).
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