Dephased FLAPS for improved visualization of susceptibility-shifted passive devices for real-time interventional MRI
Dephased FLAPS for improved visualization of susceptibility-shifted passive devices for real-time interventional MRI
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DOI：
10.1088/0031-9155/52/13/n01
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发表时间：
2007-07-07
影响因子：
3.5
通讯作者：
Dharmakumar, Rohan
中科院分区：
文献类型：
--
作者：
Koktzoglou, Ioannis;Li, Debiao;Dharmakumar, Rohan
最近，平衡稳态自由旋进（SSFP）磁共振成像在小翻转角（即FLAPS成像）已被证明优先提高附近的自旋磁化率移位介质的可见性，通过利用独特的光谱响应的SSFP信号。然而，使用FLAPS成像来可视化厚切片内的无源、易磁化性移位的设备由于部分体积效应而变得复杂，部分体积效应降低了设备的显著性。在这项工作中，失相FLAPS（dFLAPS），一种变体的FLAPS方法与失相梯度施加在切片方向上，作为一种方法，用于提高对比度的磁共振成像厚切片磁共振图像中的磁移介入设备抑制信号从共振自旋。与FLAPS成像相比，结果表明，厚的投影样切片的dFLAPS成像相对于背景信号提高了磁化率偏移设备的对比度，而不增加采集时间。
Recently, balanced steady-state free precession (SSFP) magnetic resonance imaging at small flip angles (i.e. FLAPS imaging) has been shown to preferentially enhance the visibility of spins residing near susceptibility-shifted media by exploiting the unique spectral response of SSFP signals. Nevertheless, the use of FLAPS imaging to visualize passive, susceptibility-shifted devices within thick slices is complicated by partial volume effects that reduce the conspicuity of the devices. In this work, dephased FLAPS (dFLAPS), a variation of the FLAPS method with dephasing gradients applied in the slice direction, is presented as a method for improving the contrast of susceptibility-shifted interventional devices in thick-slice magnetic resonance images by suppressing signal from on-resonant spins. In comparison to FLAPS imaging, results demonstrate that dFLAPS imaging of thick, projection-like slices improves the contrast of susceptibility-shifted devices relative to background signal with no increase in acquisition time.