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时间分割复杂化 (TDM) 序列消除了T2估计和放松-扩散测量的偏差
Qiang Liu1,2, Borjan Gagoski3,4, Imam Ahmed Shaik1
1Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States.
bioRxiv : the preprint server for biology
|June 19, 2024
概括
时间分割复杂化 (TDM) MRI 序列提供可靠和加速的放松扩散MRI (rdMRI) 微结构测量,在精度和T2估计方面表现优于多回声 (ME) 序列.
科学领域:
- 磁共振成像技术 磁共振成像技术
- 扩散式核磁共振成像 (MRI)
- 生物医学工程 生物医学工程
背景情况:
- 加速MRI采集技术对于缩短扫描时间至关重要.
- 放松-扩散MRI (rdMRI) 提供了对组织微观结构的洞察.
- 将不同的加速采集序列进行比较对于优化rdMRI至关重要.
研究的目的:
- 为了比较多回声 (ME) 和时间分割复杂化 (TDM) 序列的性能,用于加速的rdMRI.
- 评估ME和TDM在估计准确的rdMRI微结构测量的可靠性.
主要方法:
- 使用Pulseq.q.实现了ME,TDM和单回声 (SE) 序列,其中有6个回声次 (TE).
- 使用的单频段 (SB-) 和多频段2 (MB2-) 加速系数.
- 使用虚拟和体内数据的正常化根平均平方误差 (NRMSE) 量化差异,评估T2估计,REDIM和MaxEnt-RDD.
主要成果:
- TDM的业绩与SE收购的黄金标准差不多.
- 与SE和TDM相比,ME序列在图像强度和T2估计方面表现出更大的偏差.
- TDM为SE提供了可比的扩散和放松参数,而ME显示了显著的偏差.
结论:
- 与ME序列相比,TDM序列提供了更准确的放松-扩散测量.
- 在不影响准确度的情况下,TDM能够以2到3的系数加速rdMRI采集.
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