在0.55T的平衡稳定状态自由偏移相对比度应用于大动脉流量
Jie Xiang1, Rajiv Ramasawmy2, Felicia Seemann2
1Department of Biomedical Engineering, Yale University, New Haven, Connecticut, USA.
概括
一种新的心血管磁共振 (CMR) 技术,相对比平稳状态自由前行 (PC-SSFP),显著改善了0.55T的大动脉流成像的信号噪声比. 与传统方法相比,这种进步提供了更准确的流量量化方法.
科学领域:
- 心血管磁共振 (CMR) 是一种心血管磁共振技术.
- 医学成像物理 医学成像物理
- 血液动力学 血液动力学
背景情况:
- 中场 (0.55T) CMR正在获得心血管应用的吸引力,包括流量成像.
- 在0.55T的大动脉流量成像面临的挑战是信号噪声比 (SNR) 低,特别是在透气阶段,影响准确性.
- 传统的破坏性梯度召回回声 (GRE) 序列中的低SNR限制了精确的流量和反分数测量.
研究的目的:
- 开发和评估一种新的2D相位对比获取与平衡稳定状态自由前行 (PC-SSFP) 的新2D相位对比获取,以改善0.55T的大动脉流图像.
- 与传统PC-GRE相比,评估PC-SSFP在SNR和流量量化的准确性方面的性能.
- 在健康的志愿者中验证PC-SSFP的喘息和自由呼吸协议.
主要方法:
- 开发了一个2D PC-SSFP序列,设计为零梯度时刻,优化流编码采集.
- 在幻象和11名健康志愿者中测试了PC-SSFP序列,使用呼吸住和自由呼吸协议.
- 将PC-SSFP与PC-GRE进行总流量,峰值流量,心脏输出和SNR的测量. 冲击体积也与平面测量进行了比较.
主要成果:
- 在PC-SSFP中,幻象的SNR显著更高 (25.5 ± 9.6与8.2 ± 2.9),速度一致性很好 (R=1.00).
- 在志愿者中,与PC-GRE相比,PC-SSFP实现了精确的峰值流量 (R=0.99 fb,R=0.96 bh) 和心力输出 (R=0.98 fb,R=0.88 bh).
- 与平面测量相比,PC-SSFP提供了始终高的SNR (28 ± 9 fb, 24 ± 7 bh) 和精确的冲动体积测量 (R = 0.94 fb, R = 0.97 bh).
结论:
- 与PC-GRE相比,PC-SSFP是0.55T的大动脉流量量化的更可靠方法.
- 通过PC-SSFP实现的更高的SNR可以实现更准确的流量测量.
- 这种技术增强了中场CMR的实用性,用于详细的心血管评估.
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