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在0.55T时,应变编码磁共振的可行性
John L Heyniger1, Yingmin Liu2, Nikita Nair2
1The Ohio State University College of Medicine, Columbus, Ohio, USA.
概括
使用压力编码磁共振 (SENC) 的低场心血管磁共振 (CMR) 准确地测量了幽灵和志愿者的心肌压力. 在0.55T的纵向应变中,SENC显示出良好的重复性,与猪模型中的心肌梗塞相关.
科学领域:
- 心血管成像 - 心血管成像
- 医学物理 医学物理
- 生物医学工程 生物医学工程
背景情况:
- 低场 (0.55T) 宽孔心血管磁共振 (CMR) 提供了更好的可访问性.
- 在低电场下降的信号噪声比可能会影响诸如应变编码磁共振 (SENC) 等定量技术.
- 这项研究评估了0.55T的SENC性能,而不是1.5T.
研究的目的:
- 为了描述SENC在0.55T的性能.
- 评估SENC准确性,可重复性和可重复性在幻体,健康志愿者和猪心肌梗塞 (MI) 模型中.
- 为了比较0.55T和1.5T系统之间的SENC测量.
主要方法:
- 在0.55T和1.5T系统上实现了原型SENC序列.
- 在一个幻影和16名健康志愿者身上进行了扫描,其中10人接受了重复扫描以进行可重复性测试.
- 使用猪MI模型 (n=6) 与SENC和晚期加多增强 (LGE) 来评估心脏病发作和偏远地区的细分应变.
主要成果:
- 幻影SENC测量结果显示,场强度之间没有显著差异.
- 在志愿者中,全球纵向应变 (GLS) 和全球周长应变 (GCS) 在0.55T和1.5T之间是可比的 (p > 0.10).
- 类内相关性 (ICC) 表示在场强度之间LS (0.78) 的良好可重现性和CS (0.60) 的公平性;在0.55T的重复性对LS (0.89) 很好,但对CS (0.64) 公平.
- 在猪模型中,LGE+段与远程段相比显著减少了LS和CS (LS的p < 0.001,CS的p = 0.0011).
结论:
- 在0.55T时SENC是可行的,证明了精确的幻影测量和与1.5T在志愿者中的良好一致.
- 全局和细分LS在0.55T的重复性与1.5T相当,但CS的重复性较低.
- 虽然SENC显示出低场CMR的前景,但目前的CS实现可能在0.55T时缺乏足够的可靠性.
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