Evaluation of motion and its effect on brain magnetic resonance image quality in children
Evaluation of motion and its effect on brain magnetic resonance image quality in children
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DOI：
10.1007/s00247-016-3677-9
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发表时间：
2016-11-01
影响因子：
2.3
通讯作者：
Warfield, Simon K.
中科院分区：
文献类型：
--
作者：
Afacan, Onur;Erem, Burak;Warfield, Simon K.
运动伪影对儿科人群的MR图像采集造成了严重的问题，为了评估MRI扫描仪的时间运动指标及其对神经成像研究中儿科人群图像质量的影响，我们报告了一项大型儿科脑成像研究的结果，该研究显示了运动对MRI质量的影响。我们测量了82名平均年龄为13.4岁的儿科患者的运动指标，在T1加权脑MRI扫描。由于技术困难，5次扫描未纳入后续分析。放射科医生使用4分量表对图像进行分级，范围从因运动伪影导致的临床非诊断到无运动伪影。我们使用这些等级来关联运动参数，如最大运动、相对于参考点的平均位移和无运动时间与图像质量。我们的结果表明，无运动时间（占总扫描时间的比例）和相对于固定时间（获取k空间中心时）位置的平均位移与图像质量高度相关，而最大位移则不是一个很好的预测因素。在77名成功测量运动的患者中，17名患者的平均位移大于0.5 mm，其中11名（14.3%）导致非诊断性图像。同样，14名患者（18.2%）的无运动时间少于90%，这也导致了非诊断性图像。我们报告了一项大型儿科研究的结果，以显示儿童和年轻人如何在MRI扫描仪中移动，以及这种移动对图像质量的影响。这些结果将有助于运动校正界更好地理解儿科人群的运动模式以及这些模式如何影响MR图像质量。
Motion artifacts pose significant problems for the acquisition of MR images in pediatric populations.To evaluate temporal motion metrics in MRI scanners and their effect on image quality in pediatric populations in neuroimaging studies.We report results from a large pediatric brain imaging study that shows the effect of motion on MRI quality. We measured motion metrics in 82 pediatric patients, mean age 13.4 years, in a T1-weighted brain MRI scan. As a result of technical difficulties, 5 scans were not included in the subsequent analyses. A radiologist graded the images using a 4-point scale ranging from clinically non-diagnostic because of motion artifacts to no motion artifacts. We used these grades to correlate motion parameters such as maximum motion, mean displacement from a reference point, and motion-free time with image quality.Our results show that both motion-free time (as a ratio of total scan time) and average displacement from a position at a fixed time (when the center of k-space was acquired) were highly correlated with image quality, whereas maximum displacement was not as good a predictor. Among the 77 patients whose motion was measured successfully, 17 had average displacements of greater than 0.5 mm, and 11 of those (14.3%) resulted in non-diagnostic images. Similarly, 14 patients (18.2%) had less than 90% motion-free time, which also resulted in non-diagnostic images.We report results from a large pediatric study to show how children and young adults move in the MRI scanner and the effect that this motion has on image quality. The results will help the motion-correction community in better understanding motion patterns in pediatric populations and how these patterns affect MR image quality.