在具有周期动态的序列中最大限度地减少流器件
Sebastian Flassbeck1,2, Jakob Assländer1,2
1Center for Biomedical Imaging, Department of Radiology, New York University Grossman School of Medicine, New York, New York, USA.
Magnetic resonance in medicine
|November 23, 2023
概括
这项研究引入了一种新的k空间重新排序方法,以减少定量MRI中的流器件. 该技术有效地将周期脉冲序列中的图像扭曲最小化,具有平衡的梯度时刻.
科学领域:
- 磁共振成像 (MRI) 是一种磁共振成像技术.
- 医学物理 医学物理
- 图像重建 图像的重建
背景情况:
- 流是定量MRI中重要的人工制品的来源.
- 这些工件来自于平衡梯度时刻序列中的大k空间跳跃.
- 尽量减少这些文物对于准确的定量MRI至关重要.
研究的目的:
- 开发和评估一种方法来最大限度地减少流器件.
- 专注于有平衡梯度时刻的周期脉冲序列.
- 提高定量MRI数据的质量.
主要方法:
- 提出了一个新的k空间重新排序方案.
- 在重复之间交换个别的k空间线,以尽量减少时间跳跃.
- 优化问题是使用模拟回火算法来解决的.
- 这种方法利用了采样旋转动态的周期性.
主要成果:
- 在重建图像中观察到的流器件的大幅减少.
- 与默认订单相比,定量参数图显示了显著的工件减少.
- 一个最小化所有k空间跳跃的算法变体同样显示了略低的文物水平.
结论:
- 拟议的k空间重新排序有效地减少了流器件.
- 这种方法提高了定量MRI的准确性.
- 它提供了一种有效的方式来获取数据,同时最大限度地减少文物,建立在以前的方法.
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