Active catheter tracking using parallel MRI and real-time image reconstruction
Active catheter tracking using parallel MRI and real-time image reconstruction
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DOI：
10.1002/mrm.20902
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发表时间：
2006-06-01
影响因子：
3.3
通讯作者：
Semmler, Wolfhard
中科院分区：
文献类型：
--
作者：
Bock, Michael;Mueller, Sven;Semmler, Wolfhard
在这项工作中，主动MR导管跟踪与自动切片对齐与自动校准并行成像技术相结合。使用加速因子为2的优化广义自动校准部分并行采集（GRAPPA）算法，我们能够将每张图像的采集时间减少34%。为了加速实时GRAPPA图像重建，仅在切片重新定向后才更新线圈灵敏度。对于2D TrueFISP采集（160 x 256矩阵，80%相位矩阵，半傅立叶采集，TR = 3.7 ms，GRAPPA因子= 2），使用多达6个成像线圈实现实时图像重建。在单个动物实验中，该方法用于以每秒约五幅图像的图像更新速率将导管从腔静脉通过跳动的心脏转向到肺脉管系统中。在所有切片方向下，平行图像重建仅以较小的图像伪影完成，并且增加的时间分辨率提供了心内结构（例如乳头肌）的清晰描绘。
In this work active MR catheter tracking with automatic slice alignment was combined with an autocalibrated parallel imaging technique. Using an optimized generalized autocalibrating partially parallel acquisitions (GRAPPA) algorithm with an acceleration factor of 2, we were able to reduce the acquisition time per image by 34%. To accelerate real-time GRAPPA image reconstruction, the coil sensitivities were updated only after slice reorientation. For a 2D trueFISP acquisition (160 x 256 matrix, 80% phase matrix, half Fourier acquisition, TR = 3.7 ms, GRAPPA factor = 2) real-time image reconstruction was achieved with up to six imaging coils. In a single animal experiment the method was used to steer a catheter from the vena cava through the beating heart into the pulmonary vasculature at an image update rate of about five images per second. Under all slice orientations, parallel image reconstruction was accomplished with only minor image artifacts, and the increased temporal resolution provided a sharp delineation of intracardial structures, such as the papillary muscle.