Forman Christoph, Piccini Davide, Grimm Robert, Hutter Jana, Hornegger Joachim, Zenge Michael O
Pattern Recognition Lab, Department of Computer Science, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058, Erlangen, Germany,
MAGMA. 2014 Oct;27(5):435-43. doi: 10.1007/s10334-013-0428-x. Epub 2014 Jan 9.
To study a scan protocol for coronary magnetic resonance angiography based on multiple breath-holds featuring 1D motion compensation and to compare the resulting image quality to a navigator-gated free-breathing acquisition. Image reconstruction was performed using L1 regularized iterative SENSE.
The effects of respiratory motion on the Cartesian sampling scheme were minimized by performing data acquisition in multiple breath-holds. During the scan, repetitive readouts through a k-space center were used to detect and correct the respiratory displacement of the heart by exploiting the self-navigation principle in image reconstruction. In vivo experiments were performed in nine healthy volunteers and the resulting image quality was compared to a navigator-gated reference in terms of vessel length and sharpness.
Acquisition in breath-hold is an effective method to reduce the scan time by more than 30% compared to the navigator-gated reference. Although an equivalent mean image quality with respect to the reference was achieved with the proposed method, the 1D motion compensation did not work equally well in all cases.
In general, the image quality scaled with the robustness of the motion compensation. Nevertheless, the featured setup provides a positive basis for future extension with more advanced motion compensation methods.
研究基于多次屏气且具有一维运动补偿的冠状动脉磁共振血管造影扫描协议,并将所得图像质量与导航门控自由呼吸采集的图像质量进行比较。使用L1正则化迭代敏感性编码(SENSE)进行图像重建。
通过多次屏气进行数据采集,将呼吸运动对笛卡尔采样方案的影响降至最低。在扫描过程中,利用图像重建中的自导航原理,通过k空间中心的重复读出检测并校正心脏的呼吸位移。对9名健康志愿者进行了体内实验,并根据血管长度和清晰度将所得图像质量与导航门控参考图像进行比较。
与导航门控参考相比,屏气采集是一种将扫描时间减少30%以上的有效方法。尽管所提出的方法实现了与参考图像相当的平均图像质量,但一维运动补偿在所有情况下的效果并不相同。
一般来说,图像质量与运动补偿的稳健性成正比。然而,该特色设置为未来采用更先进的运动补偿方法进行扩展提供了积极的基础。