磁化转移效应对定量MR成像中的T1测量的影响:比较二维多动态多回声 (2D-MDME) 和三维量化,使用交叉的Look-Locker获取序列 (3D-QALAS) 协议对两个系统
Ryoichi Kose1, Katsumi Kose1, Yasuhiko Terada2
1MRIsimulations, Tokyo, Japan.
概括
磁化转移效应显著影响2D多动态多重回声 (2D-MDME) MRI中的T1测量,导致缩短. 然而,3D-QALAS (3D-QuAntification使用交叉的Look-Locker获取序列与T2准备脉冲) 没有受到影响,这凸显了在多参数定量MRI比较中需要考虑MT效应的必要性.
科学领域:
- 磁共振成像技术 磁共振成像技术
- 量化MRI是指数量化的MRI.
- 生物医学工程 生物医学工程
背景情况:
- 多参数定量核磁共振 (MP-qMRI) 方法可同时测量多个放松时间.
- 不同的MP-qMRI技术之间的关系仍然不清楚,阻碍了直接比较.
- 2D多动态多重回声 (2D-MDME) 是广泛使用的,但与3D-QALAS (3D-QuAntification使用交联的Look-Locker获取序列与T2准备脉冲) 等潜在的继任者进行比较是缺乏的.
研究的目的:
- 为了研究2D-MDME和3D-QALAS MP-qMRI方法之间的关系.
- 评估磁化转移 (MT) 影响对两种技术T1测量的影响.
- 确定2D-MDME和3D-QALAS在临床环境中的可比性.
主要方法:
- 在1.5T和3TMRI系统上实施2D-MDME和3D-QALAS.
- 使用MP-qMRI两种方法测量幻影的放松时间.
- 对MT影响对T1放松时间测量的影响进行了集中分析.
主要成果:
- 由于MT的影响,2D-MDME显示T1缩短约20%-35%.
- 3D-QALAS显示MT对T1测量的影响没有显著的影响.
- 这两种方法之间的T1测量差异归因于MT效应.
结论:
- 在临床研究中比较2D-MDME和3D-QALAS时,必须考虑磁化转移效应.
- 对于MT效应,3D-QALAS似乎比2D-MDME对T1量化更强大.
- 仔细的方法选择和数据解释对于准确的MP-qMRI分析至关重要.
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