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在0.55T时螺旋轮旋转回声的同时场补偿
Rajiv Ramasawmy1, John P Mugler2, Ahsan Javed3
1Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA. rajiv.ramasawmy@nih.gov.
Magma (New York, N.Y.)
|June 12, 2023
概括
低场MRI神经成像通过螺旋回声对回声补偿得到了改进. 这种方法减少了0.55T的螺旋轮回旋回声 (TSE) 成像中的工件,提高了诊断质量和获取效率.
科学领域:
- 磁共振成像技术 磁共振成像技术
- 低波场核磁共振 (MRI) 是一种低波场核磁共振.
- 神经成像是一种神经成像.
背景情况:
- 具有诊断质量的神经成像需要高效的MRI方法,特别是在较低的磁场强度下.
- 低场MRI (0.55 T) 面临的挑战是信号噪声比下降和同时增加的场文物.
- 螺旋成像提供了效率,但容易受到这些工件的影响.
研究的目的:
- 开发和验证一个可通用的二次梯度场取消技术,用于回声对回声补偿.
- 为了减轻螺旋轮旋回回声 (TSE) 在0.55 T.的收购中同时出现的现场工件.
- 提高低场MRI神经成像的效率和诊断质量.
主要方法:
- 开发了一种螺旋式进出TSE采集,具有双极梯度,用于并发场补偿.
- 利用模拟来描述和优化补偿策略.
- 在幻影和8名健康志愿者中验证了0.55T的方法.
主要成果:
- 拟议的回声对回声补偿有效地减轻了螺旋读出中的并发场文物.
- 模拟预测,回声之间同时发生的场相根平均平方误差 (RMSE) 减少了42%.
- 螺旋TSE显示信号与噪声比率 (SNR) 与卡特西安采集相比提高了17.2%.
结论:
- 使用二次式-取消梯度的可概括方法有效地减少了螺旋TSE中的并发场文物.
- 这种补偿技术提高了低场MRI的神经成像质量.
- 该方法提高了采集效率,促进了低场MRI的更广泛的临床采用.
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