Advantages and limitations of prospective head motion compensation for MRI using an optical motion tracking device
Advantages and limitations of prospective head motion compensation for MRI using an optical motion tracking device
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DOI：
10.1016/j.acra.2006.05.010
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发表时间：
2006-09-01
影响因子：
4.8
通讯作者：
Sakas, Georgios
中科院分区：
文献类型：
--
作者：
Dold, Christian;Zaitsev, Maxim;Sakas, Georgios
理由和目标。受试者运动似乎是许多磁共振（MR）成像（MRI）应用中的限制因素。特别地，经常伴随中风的头部震颤可能使得某些高分辨率二维（213）和三维（3D）技术不适用。其原因是采集过程中的头部移动。本研究的目的是实现一种方法，能够补偿完整的运动在数据采集。该方法应可用于每个序列，并易于在不同的MR扫描仪上实现。的可能性接口的MR扫描仪与外部光学运动跟踪系统能够确定对象的位置与亚毫米级的精度和更新速率为60赫兹。基于跟踪数据，在采集k-空间数据的过程中，通过重新计算MR扫描仪的梯度和射频参数，更新视野（FOV），利用目标位置（头部）的运动信息来补偿真实的运动。旋转体模，在体内实验的结果，并执行三种不同的MRI序列，2D自旋回波，3D梯度回波，回波平面成像，。最后，将所提出的方法与扫描仪软件上的前瞻性运动校正软件进行了比较。提出了一种仅通过更新MR扫描仪的FOV而在真实的时间内工作的前瞻性运动校正方法。结果表明，使用外部光学运动跟踪系统，以补偿采集过程中的强烈和快速的主题运动的可行性。
Rationale and Objectives. Subject motion appears to be a limiting factor in numerous magnetic resonance (MR) imaging (MRI) applications. In particular, head tremor, which often accompanies stroke, may render certain high-resolution two(213) and three-dimensional (3D) techniques inapplicable. The reason for that is head movement during acquisition. The study objective is to achieve a method able to compensate for complete motion during data acquisition. The method should be usable for every sequence and easily implemented on different MR scanners.Materials and Methods. The possibility of interfacing the MR scanner with an external optical motion-tracking system capable of determining the object's position with submillimeter accuracy and an update rate of 60 Hz is shown. Movement information on the object position (head) is used to compensate for motion in real time by updating the field of view (FOV) by recalculating the gradients and radiofrequency parameter of the MR scanner during acquisition of k-space data, based on tracking data.Results. Results of rotation phantom, in vivo experiments, and implementation of three different MRI sequences, 2D spin echo, 3D gradient echo, and echo planar imaging, are presented. Finally, the proposed method is compared with the prospective motion correction software available on the scanner software.Conclusion. A prospective motion correction method that works in real time only by updating the FOV of the MR scanner is presented. Results show the feasibility of using an external optical motion-tracking system to compensate for strong and fast subject motion during acquisition.