Self-navigated prospective motion correction for 3D-EPI acquisition.
Self-navigated prospective motion correction for 3D-EPI acquisition.
复制标题
用于 3D-EPI 采集的自导航前瞻性运动校正。
DOI：
10.1002/mrm.29202
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发表时间：
2022
影响因子：
3.3
通讯作者：
Meintjes,ErnestaM
中科院分区：
文献类型：
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作者：
Bayih,SamuelGetaneh;Jankiewicz,Marcin;Alhamud,A;vanderKouwe,AndréJW;Meintjes,ErnestaM
目的虽然3D EPI比2D EPI更容易受到运动伪影的影响，但它为功能MRI带来了一些好处，包括没有自旋历史伪影，并行成像加速的可能性更大，以及在高分辨率成像中更好的功能灵敏度。在这里，我们提出了一个自我导航的3D-EPI序列适用于前瞻性运动校正功能MRI没有额外的硬件或pulses.MethodsFor每一个体积采集，前24个52分区被收购被累积到一个新的反馈块，被添加到图像重建管道。在对剩余分区进行零填充后，反馈模块构建体积自导航器（vSNav），将其与第一次体积采集期间采集的参考vSNav共配准，并将运动估计值发送到序列。然后，序列更新其FOV，并利用调整后的FOV获取后续分区，直到接收到下一次更新。该序列进行了验证，没有和有意的运动，在体模和体内的3 T Skyra.ResultsFor体模扫描，FOV更新后0.704 s收购thevSNav分区，并在体内扫描后0.768 s。体模和体内数据都证明了在没有运动的情况下的稳定运动估计。对于体内采集，前瞻性的头部姿势估计使用thevSNav的和回顾性的估计与FLIRT（FMRIB的线性图像配准工具）同意在0.23 mm（< 10%的切片厚度）和0.14°在所有direction. ConclusionDependent运动发生在一个体积采集过程中，所提出的方法完全纠正FOV和恢复图像质量在一个体积采集。
PurposeAlthough 3D EPI is more susceptible to motion artifacts than 2D EPI, it presents some benefits for functional MRI, including the absence of spin‐history artifacts, greater potential for parallel imaging acceleration, and better functional sensitivity in high‐resolution imaging. Here we present a self‐navigated 3D‐EPI sequence suitable for prospective motion‐corrected functional MRI without additional hardware or pulses.MethodsFor each volume acquisition, the first 24 of the 52 partitions being acquired are accumulated to a new feedback block that was added to the image reconstruction pipeline. After zero‐filling the remaining partitions, the feedback block constructs a volumetric self‐navigator (vSNav), co‐registers it to the referencevSNavacquired during the first volume acquisition, and sends motion estimates to the sequence. The sequence then updates its FOV and acquires subsequent partitions with the adjusted FOV, until the next update is received. The sequence was validated without and with intentional motion in phantom and in vivo on a 3T Skyra.ResultsFor phantom scans, the FOV was updated 0.704 s after acquisition of thevSNavpartitions, and for in vivo scans after 0.768 s. Both phantom and in vivo data demonstrated stable motion estimates in the absence of motion. For in vivo acquisitions, prospective head‐pose estimates using thevSNav's and retrospective estimates with FLIRT (FMRIB's Linear Image Registration Tool) agreed to within 0.23 mm (< 10% of the slice thickness) and 0.14° in all directions.ConclusionDepending when motion occurs during a volume acquisition, the proposed method fully corrects the FOV and recovers image quality within one volume acquisition.