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脂肪抑制方法的有效性和对质子共振频率转移 (PRFS) MR温度计的影响

Anne Josset¹, Jonathan Vappou¹, Ounay Ishak¹

¹Université de Strasbourg, CNRS, INSERM, ICube, UMR7357, Strasbourg, France.

Magnetic resonance imaging

|February 1, 2025

概括

像水激发 (WE) 和光谱脂肪和 (FS) 等脂肪抑制技术可以减少质子共振频率转移 (PRFS) MR-温度计中的错误. 然而,残留脂肪信号仍然可能导致温度不准确,需要对定量MRI方法进行特定评估.

科学领域:

磁共振成像 (MRI) 是一种磁共振成像技术.
医学物理医学物理
生物医学工程生物医学工程

背景情况:

质子共振频率转移 (PRFS) MR-温度计是测量温度的定量MRI方法.
准确的PRFS温度测量对于热除监测等应用至关重要.
脂肪抑制技术经常在MRI中使用,以减轻脂肪信号干扰.

研究的目的:

通过实验评估不同脂肪抑制技术的有效性.
评估这些技术对PRFSMR温度计准确性的影响.

主要方法:

使用油幻体和猪骨髓中的水脂肪分解来测量剩余脂肪峰值的大小.
在1.5TMRI扫描仪上比较光谱脂肪和 (FS),水激发 (WE) 和快速水激发 (FWE).
在PRFS温度计中使用不同脂肪含量 (10%,30%) 的油水幻象与光纤温度计相比,确定了温度误差.

主要成果:

在油幻影中,水激发 (WE) 与FS (2%的振幅) 相比,主要脂肪峰 (22%的振幅) 的衰减更大.
与没有脂肪抑制相比,FS和WE都显著减少了PRFS温度测量的温度误差.
抑制后的剩余脂肪信号导致温度误差,这取决于脂肪含量,回声时间 (TE) 和温度.

结论:

建议采用一项协议,在脂肪抑制后量化残留光谱脂肪峰值.
在PRFS温度计中的残留脂肪信号可以导致温度低估或高估,这取决于TE,脂肪分数和温度.
脂肪抑制技术需要对定量MRI方法 (如PRFS MR-温度计) 进行特定的评估.

关键词:

脂肪量化的量化方法抑制脂肪抑制脂肪的方法在MR温度测试中使用MR温度计.量化MRI是指数量化的MRI.水与脂肪的分离方法

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