旋转框架放松时间T2ρ的量化:平衡自旋锁和连续波马尔科姆-莱维特制剂的比较
Maximilian Gram1,2, Martin Christa1,3, Fabian Tobias Gutjahr2
1Department of Internal Medicine I, University Hospital Würzburg, Würzburg, Germany.
NMR in biomedicine
|June 26, 2024
概括
一种用于T2ρ映射的新方法,连续波马尔科姆-莱维特 (CW-MLEV) 脉冲列车,与T1ρ适应的技术相比,提供了更高的稳定性,特别是在场内不均性的情况下.
科学领域:
- 磁共振成像是一种磁共振成像技术.
- 生物医学工程 生物医学工程
- 物理 物理学 物理
背景情况:
- T2ρ放松通路对于量化旋转放松时间至关重要.
- 与T1ρ相比,T2ρ成像的探索较少,准备技术往往是从T1ρ方法中改编的.
- 需要强大的T2ρ映射,以便在各种应用中准确量化.
研究的目的:
- 为了比较T2ρ映射的两个准备概念:由T1ρ改编的平衡自旋锁 (B-SL) 和一种新的连续波马尔科姆-莱维特 (CW-MLEV) 脉冲列车.
- 用Bloch模拟来评估这些方法对现场不均性的内在灵敏度.
- 在幻影实验中验证性能,并证明在小鼠心肌T2ρ映射中的示例应用.
主要方法:
- 对比B-SL和CW-MLEV脉冲列车准备技术用于T2ρ映射.
- 布洛赫模拟用于评估对磁场同质性的敏感性.
- 幻影实验用于验证.
- 在小鼠体内心肌T2ρ映射在7特斯拉.
主要成果:
- 在CW-MLEV方法中,CW-MLEV方法在现场同质性下,与B-SL相比,显示出更高的稳定性和带宽补偿 (4.1的因素).
- 模拟表明CW-MLEV对抗场变化的稳定性增加.
- 在小鼠的左心室T2ρ的一致量化结果在7T时为59.2-61.1 ms (R2 = 0.986-0.992) 的值.
结论:
- 已建立的T1ρ成像方法对于T2ρ实验来说并不理想.
- 新的CW-MLEV脉冲列车为T2ρ映射提供了更强大,更可靠的方法.
- CW-MLEV适用于准确的体内T2ρ定量,如在小鼠心肌中所示.
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