Simultaneous parallel inclined readout image technique
Simultaneous parallel inclined readout image technique
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DOI：
10.1016/j.mri.2005.12.019
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发表时间：
2006-06-01
影响因子：
2.5
通讯作者：
Whitby, Elspeth H.
中科院分区：
文献类型：
--
作者：
Paley, Martyn N. J.;Lee, Kuan J.;Whitby, Elspeth H.
灵敏度编码相位欠采样与同步切片激励相结合，产生了一种具有高体积采集加速因子的并行MRI方法，而不需要辅助的阶梯场线圈。双片激励是通过调制+/-6 kHz的自旋和梯度回波序列产生的。通过在数据采集过程中沿切片轴施加额外的梯度，防止了同时激发切片的频率混叠。数据采集使用四通道接收器阵列和在1.5 T MR系统上的x4灵敏度编码。同时平行倾斜读出图像技术已成功地在幻影和志愿者身上进行了演示。实现了高达x8的乘法图像采集加速因子。图像的信噪比和分辨率取决于读出梯度与附加切片梯度的比值。大约2:1的比例产生可接受的图像质量。使用具有附加激励带的射频脉冲应使该技术能够扩展到X 16-24范围内的体积采集加速因子，而不受纯部分并行相位减少方法的信噪比限制。(C) 2006爱思唯尔公司版权所有。
Sensitivity-encoded phase undersampling has been combined with simultaneous slice excitation to produce a parallel MRI method with a high volumetric acquisition acceleration factor without the need for auxiliary stepped field coils.Dual-slice excitation was produced by modulating both spin and gradient echo sequences at +/-6 kHz. Frequency aliasing of simultaneously excited slices was prevented by using an additional gradient applied along the slice axis during data acquisition. Data were acquired using a four-channel receiver array and x4 sensitivity encoding on a 1.5 T MR system. The simultaneous parallel inclined readout image technique has been successfully demonstrated in both phantoms and volunteers. A multiplicative image acquisition acceleration factor of up to X 8 was achieved. Image SNR and resolution was dependent on the ratio of the readout gradient to the additional slice gradient. A ratio of approximately 2:1 produced acceptable image quality. Use of RF pulses with additional excitation bands should enable the technique to be extended to volumetric acquisition acceleration factors in the range of X 16-24 without the SNR limitations of pure partially parallel phase reduction methods. (C) 2006 Elsevier Inc. All rights reserved.