在体内同时进行质子共振频率转移温度测量和单个参考变量翻转角T1测量
Nicholas Richards1, Michael Malmberg1, Henrik Odéen2
1Department of Biomedical Engineering, University of Utah, Salt Lake City, Utah, USA.
Magnetic resonance in medicine
|January 20, 2025
概括
这项研究展示了一种新的MRI序列,用于在体内同时测量温度,使用质子共振频率 (PRF) 转移和基于T1的温度计,适用于肌肉和脂肪组织.
科学领域:
- 磁共振成像 (MRI) 是一种磁共振成像技术.
- 生物医学工程 生物医学工程
- 医学物理 医学物理
背景情况:
- 准确的温度监测对于MR指导聚焦超声波 (MRgFUS) 疗法至关重要.
- 现有的温度计方法在同时评估不同类型组织,特别是脂肪组织的温度变化方面存在局限性.
研究的目的:
- 为了评估单个参考可变翻转角度序列与多回声堆获取恒星 (SR-VFA-SoS) 的有效性,用于同时测温.
- 评估在MRgFUS期间在体内子模型中对质子共振频率 (PRF) 转移和基于T1的温度计的性能.
主要方法:
- 在MRgFUS.US期间,SR-VFA-SoS序列在3T时在子模型 (n=7) 中使用.
- 不同的组织位置 (肌肉,脂肪和它们的接口) 被加热,并同时使用PRF转移和T1方法测量温度变化.
- 脂肪的T1温度系数被确定为ex vivo,并应用于体内温度映射.
主要成果:
- SR-VFA-SoS序列在1.5x1.5x2毫米的音像分辨率下实现了1.71秒的时间分辨率.
- PRF转移温度计对脂肪的加热不敏感,而基于T1的温度计检测到脂肪的温度变化 (平均系数:1.9%/°C ±0.2%/°C).
- 温度计精度为0.76°C ± 0.18°C,用于肌肉中的PRF转移,为1.93°C ± 0.60°C,用于脂肪中的T1基温度计.
结论:
- 该SR-VFA-SoS序列允许同时使用PRF转移和基于T1的方法进行MR温度计.
- 这种技术在体内MRgFUS过程中为水性和脂肪组织提供了有效的温度监测.
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