Accuracy of 4D Flow Measurement of Cerebrospinal Fluid Dynamics in the Cervical Spine: An In Vitro Verification Against Numerical Simulation
Accuracy of 4D Flow Measurement of Cerebrospinal Fluid Dynamics in the Cervical Spine: An In Vitro Verification Against Numerical Simulation
复制标题
DOI：
10.1007/s10439-016-1602-x
复制
发表时间：
2016-11-01
影响因子：
3.8
通讯作者：
Martin, Bryn A.
中科院分区：
文献类型：
--
作者：
Pahlavian, Soroush Heidari;Bunck, Alexander C.;Martin, Bryn A.
脑脊液（CSF）流动的异常改变被认为在各种颅脊髓疾病（如脑积水和Chiari畸形）的病理生理中起重要作用。三维相位对比MRI （4D Flow）已被提出作为一种量化健康和疾病状态下脑脊液动力学的方法，但在进一步实施该技术之前，必须评估其测量脑脊液速度大小和分布的准确性。在本研究中，基于解剖细节的3D打印颈椎蛛网膜下腔模型和受试者特定的流动边界条件，开发了一个核磁共振兼容的实验平台。通过比较体外模型中获得的CSF速度与基于相同几何形状和流动边界条件的空间平均计算流体动力学（CFD）模型计算的数值预测速度，评估4D流量测量的准确性。CFD和4D Flow在通过平面速度的空间分布和峰值大小方面表现出良好的一致性，收缩期峰值和舒张期峰值的平均差异分别为7.5%和10.6%。回归分析显示，在低CSF流速对应的时间段内，4D流量测量精度较低，CFD与4D Flow平面内速度相关性较差。
Abnormal alterations in cerebrospinal fluid (CSF) flow are thought to play an important role in pathophysiology of various craniospinal disorders such as hydrocephalus and Chiari malformation. Three directional phase contrast MRI (4D Flow) has been proposed as one method for quantification of the CSF dynamics in healthy and disease states, but prior to further implementation of this technique, its accuracy in measuring CSF velocity magnitude and distribution must be evaluated. In this study, an MR-compatible experimental platform was developed based on an anatomically detailed 3D printed model of the cervical subarachnoid space and subject specific flow boundary conditions. Accuracy of 4D Flow measurements was assessed by comparison of CSF velocities obtained within the in vitro model with the numerically predicted velocities calculated from a spatially averaged computational fluid dynamics (CFD) model based on the same geometry and flow boundary conditions. Good agreement was observed between CFD and 4D Flow in terms of spatial distribution and peak magnitude of through-plane velocities with an average difference of 7.5 and 10.6% for peak systolic and diastolic velocities, respectively. Regression analysis showed lower accuracy of 4D Flow measurement at the timeframes corresponding to low CSF flow rate and poor correlation between CFD and 4D Flow in-plane velocities.