对于加速相循环23Na多量子一致性MRI的噪声强的后处理管道
Christian Licht1, Efe Ilicak2, Fernando E Boada3
1Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany; Mannheim Institute for Intelligent Systems in Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany; Radiological Sciences Laboratory, School of Medicine, Stanford University, Stanford, California, USA.
Zeitschrift fur medizinische Physik
|January 22, 2025
概括
这项研究引入了 (Na) 多量子一致性 (MQC) MRI 的新管道,提高了图像质量并减少了扫描时间. 该方法提高了信号与噪声的比率,并强大地分离信号,以获得更好的大脑成像7特斯拉.
科学领域:
- 医疗成像医学成像
- 生物物理学的生物物理.
- 神经成像是一种神经成像.
背景情况:
- (Na23) 多量子连贯性 (MQC) 核磁共振是有价值的体内人类大脑成像在7特斯拉.
- 目前的MQCMRI技术面临的挑战是低信号噪声比 (SNR) 和漫长的射频 (RF) 阶段循环.
- 单量子 (SQ) 和三量子 (TQ) 信号的准确分离对于计算TQ/SQ比率至关重要,这是一个关键的诊断参数.
研究的目的:
- 开发一个先进的后处理管道,以对抗噪声,加速NaMQCMRI的体内人类大脑在7T.
- 为了增强SNR和改善SQ和TQ信号组件的分离在Na MQCMRI.
- 为了减少采集时间,同时保持高图像质量.
主要方法:
- 结合低级 k 空间无声化用于 SNR 增强与动态模式分解 (DMD) 进行强大的 SQ 和 TQ 信号分离.
- 验证了 in silico, in vitro 和 in vivo 的管道,并将其与传统的消极化和富里埃转换 (FT) 方法进行比较.
- 通过模拟受损的射频相循环步骤的废弃实验来评估管道的稳定性.
主要成果:
- 与未被拒绝的图像相比,拒绝算法增加了SNR的两倍,并且在波形拒绝上提高了SNR高达29%.
- 与FT方法相比,DMD有效地分离了SQ和TQ信号,即使没有完整的RF相循环,也实现了优越的SSIM (0.89±0.024) 和较低的RMSE (0.055±0.008).
- 启用了高质量的8x8x15mm3 in vivo23Na MQC MRI,采集时间从48分钟缩短到10分钟.
结论:
- 拟议的管道通过低级别的无声化和基于DMD的信号分离,显著提高了Na MQCMRI的稳定性.
- 对于SQ和TQ组件,即使在加速和不完整的RF相循环条件下,也可以获得高质量的MR图像.
- 这种方法为人类大脑的先进Na MQCMRI提供了更有效和可靠的方法.
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