运动补偿旋转回声心脏扩散张力成像在多个心脏阶段使用超高梯度强度扫描仪
Shubhajit Paul1, Camila Munoz1, Pedro F Ferreira1
1Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Guy's and St Thomas' NHS Foundation Trust, London, UK; National Heart and Lung Institute, Imperial College London, London UK.
概括
超高梯度强度系统通过增加信号对噪声比率和增强透气成像来改善心脏扩散张力成像 (cDTI). 这一进步有助于通过运动补偿自旋回声 (MCSE) 技术识别心脏中的动态微结构变化.
科学领域:
- 心血管成像 - 心血管成像
- 扩散张力成像 扩散张力成像
- 磁共振成像 物理 物理
背景情况:
- 传统的心脏扩散张力成像 (cDTI) 依赖于低效的刺激回声技术来评估心脏微观结构.
- 超高梯度强度系统可实现更短的运动补偿扩散编码,从而有可能提高cDTI的效率和稳定性.
- 这项研究研究了高和超高梯度强度在静脉缩和腹缩期间的运动补偿自旋回声 (MCSE) cDTI 的比较性能.
研究的目的:
- 为了比较高 (GH) 与超高 (GUH) 梯度强度在获得心和腹运动补偿旋回回声心脏扩散张力成像 (MCSE cDTI) 的有效性.
- 为了评估图像质量,特别是信号噪声比 (SNR) 和两个梯度强度之间的微结构参数准确性.
- 评估不同梯度强度的MCSE cDTI在整个心脏周期内检测心脏微结构动态变化的能力.
主要方法:
- 第二阶MCSE序列开发并应用于西门子3T Connectom扫描仪 (300mT/m最大梯度振幅).
- 屏息cDTI数据是在缩的峰值和缩的结束时获得的,使用最大可实现的超高梯度强度 (GUH,116mT/m) 和有限的高梯度强度 (GH,66mT/m).
- 图像参数包括特定的回声时间 (TE),voxel分辨率 (2.8×2.8x8mm3),b值 (b=500s/mm2,b=150s/mm2) 和6个编码方向.
主要成果:
- 无论是GUH还是GH,都在静脉收购方面取得了较高的成功率,而在静脉收购方面,GUH的表现略有更好.
- 超高梯度强度 (GUH) 导致SNR显著高于高梯度强度 (GH) 在透析和收缩阶段.
- 在静脉缩和腹缩之间观察到分数异位性,横向螺旋角梯度 (HAG) 和叶片角 (RadiE2A) 的差异,其中一些相位特异性差异在GUH或GH中更明显.
结论:
- 超高梯度强度系统为MCSE cDTI提供了卓越的SNR和更强大的透气成像.
- 虽然透析成像的可靠性需要进一步改进,但GUH可以识别动态心脏微结构变化.
- 这些发现支持多相MCSEcDTI与超高梯度强度的更广泛的临床研究应用.
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