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一种快速的磁流密度测量方法,使用Skip-Echo获得的Turbo Spin Echo (SATE)
IEEE transactions on bio-medical engineering
|June 19, 2023
概括
一个新的Skip-Echo获得的Turbo Spin Echo (SATE) 序列加速了MREIT和MRCDI的磁流密度 (Bz) 测量. 这种更快的方法可以在临床时间框架内进行可靠的体积Bz映射.
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
- 医学物理 医学物理
背景情况:
- 磁共振电阻断层扫描 (MREIT) 和磁共振电流密度成像 (MRCDI) 需要测量磁流密度 (Bz).
- 传统的基于旋回回声 (SE) 的Bz获取序列对于临床使用来说太慢了.
- 加速成像技术对于推进MREIT和MRCDI应用至关重要.
研究的目的:
- 开发和验证用于快速Bz测量的新型成像序列.
- 为了提高MREIT和MRCDI的Bz数据采集的效率和速度.
- 为了在临床上相关的时间内实现体积Bz映射.
主要方法:
- 在传统的旋回声 (TSE) 采集之前,通过整合一个跳过回声模块来开发了一个跳过回声获得的旋回声 (SATE) 序列.
- 在SATE中使用了振幅调节的粉碎器梯度和特别选择的射频 (RF) 脉冲形状,以消除不需要的信号路径并保持信号完整性.
- 使用幻影实验评估了SATE序列的效率和准确性,并与多回声注入电流非线性编码 (ME-ICNE) 方法进行了比较.
主要成果:
- 与标准TSE序列相比,SATE序列显示了提高的测量效率.
- 通过SATE实现的数据采集速度比传统方法快10倍.
- 在临床上可接受的时间内,在幽灵,猪肉和人类小牛中成功获得了准确的体积Bz图.
结论:
- 拟议的SATE序列在Bz测量中提供了显著的加速.
- SATE为体积Bz映射提供了一种快速有效的方法.
- 这种加速方法极大地促进了MREIT和MRCDI技术的临床转化.
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