The Relationship of Three-Dimensional Human Skull Motion to Brain Tissue Deformation in Magnetic Resonance Elastography Studies
The Relationship of Three-Dimensional Human Skull Motion to Brain Tissue Deformation in Magnetic Resonance Elastography Studies
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DOI：
10.1115/1.4036146
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发表时间：
2017-05-01
影响因子：
1.7
通讯作者：
Bayly, Philip V.
中科院分区：
文献类型：
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作者：
Badachhape, Andrew A.;Okamoto, Ruth J.;Bayly, Philip V.
在创伤性脑损伤(TBI)中，硬脑膜、蛛网膜和软脑膜在将运动从颅骨传递到脑组织中起着至关重要的作用。磁共振弹性成像(MRE)是一种用于无创估计软组织材料参数的成像技术。在磁共振成像中，脑组织的动态变形是由磁共振成像(MRI)过程中的颅骨振动引起的，然而，颅骨运动及其传递到大脑的方式在很大程度上仍不清楚。在这项研究中，使用一组MRI安全的加速度计的数据重建的颅骨中点的位移，与根据MRE测量估计的脑组织中邻近物质点的位移进行了比较。比较了6名受试者头骨和大脑中简谐运动的相对幅度、方向和时间相位，发现头骨-大脑界面显著地衰减和延迟了运动从头骨到大脑的传递。相比之下，在圆柱形明胶“模体”中，刚性壳的位移(根据加速度计数据重建)被传输到明胶内部(根据MRE数据估计)，几乎没有衰减或相位滞后。这种对颅脑界面的定量描述将在脑外伤计算机模型的参数化和验证中具有价值。
In traumatic brain injury (TBI), membranes such as the dura mater, arachnoid mater, and pia mater play a vital role in transmitting motion from the skull to brain tissue. Magnetic resonance elastography (MRE) is an imaging technique developed for noninvasive estimation of soft tissue material parameters. In MRE, dynamic deformation of brain tissue is induced by skull vibrations during magnetic resonance imaging (MRI); however, skull motion and its mode of transmission to the brain remain largely uncharacterized. In this study, displacements of points in the skull, reconstructed using data from an array of MRI-safe accelerometers, were compared to displacements of neighboring material points in brain tissue, estimated from MRE measurements. Comparison of the relative amplitudes, directions, and temporal phases of harmonic motion in the skulls and brains of six human subjects shows that the skull-brain interface significantly attenuates and delays transmission of motion from skull to brain. In contrast, in a cylindrical gelatin "phantom," displacements of the rigid case (reconstructed from accelerometer data) were transmitted to the gelatin inside (estimated from MRE data) with little attenuation or phase lag. This quantitative characterization of the skull-brain interface will be valuable in the parameterization and validation of computer models of TBI.