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加速的多次量子过的磁共振成像使用压缩传感在7 T
Qingping Chen1, Wieland A Worthoff2, N Jon Shah3
1Institute of Neuroscience and Medicine - 4, Forschungszentrum Jülich GmbH, Jülich, Germany; Faculty of Medicine, RWTH Aachen University, Aachen, Germany.
Magnetic resonance imaging
|January 3, 2024
概括
压缩传感 (CS) 在7T加速增强单次和三次量子过的MRI (eSISTINA),减少噪声和采集时间. 这一进步提高了MRI生物标志物的图像质量和临床适用性.
科学领域:
- 医疗成像医学成像
- 生物物理学的生物物理.
- 磁共振成像是一种磁共振成像技术.
背景情况:
- 多次量子过 (MQF) MRI,包括23Na (eSISTINA) 的增强单次和三次量子过成像,为限制提供了洞察力,这是一个关键的临床生物标志物.
- 然而,传统的eSISTINA序列面临着采集时间长和图像质量低于最佳的挑战,限制了临床使用.
研究的目的:
- 开发和实施一个新的eSISTINA序列在7特斯拉 (7T) 结合压缩传感 (CS).
- 使用CS加速eSISTINA的获取,而不影响基本的图像信息或生物标志物权重.
主要方法:
- 一个基于3D螺旋采样eSISTINA序列在7T实现了CS应用程序.
- 对完全采样的幻象和人类受试者数据进行了回顾性低样本测试,将CS重建与非均快里叶变换 (NUFFT) 进行了比较.
- 评估指标包括结构相似性 (SSIM),信号与噪声比 (SNR),区间权重和定量准确性.
主要成果:
- 基于CS的重建表明,幻影和体内图像中的噪声减少和结构细节增强.
- 在SNR和SSIM中,CS在总体上表现优于NUFFT,保留了重要的分区权重.
- 准确的体内定量估计得到了不到15%的误差,在双重低样本因子下.
结论:
- 该研究成功地实施了eSISTINA序列,在7T时采用不连贯的采样,利用CS加速.
- CS可使eSISTINA在7T时加速两倍,比NUFFT产生更低的噪声,同时保持结构信息和定量准确性.
- 通过CS缩短的获取时间显著提高了MQFMRI的潜在临床效用.
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