Accuracy of 4D Flow Measurement of Cerebrospinal Fluid Dynamics in the Cervical Spine: An In Vitro Verification Against Numerical Simulation

• Published in: Annals of biomedical engineering Vol. 44; no. 11; pp. 3202 - 3214
• Main Authors: Heidari Pahlavian, Soroush, Bunck, Alexander C., Thyagaraj, Suraj, Giese, Daniel, Loth, Francis, Hedderich, Dennis M., Kröger, Jan Robert, Martin, Bryn A.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.11.2016; Springer Nature B.V
• Subjects: Accuracy; Biochemistry; Biological and Medical Physics; Biomedical and Life Sciences; Biomedical Engineering and Bioengineering; Biomedicine; Biophysics; Boundary conditions; Cerebrospinal fluid; Cerebrospinal Fluid - metabolism; Cervical Cord - diagnostic imaging; Cervical Cord - metabolism; Cervical Vertebrae - diagnostic imaging; Cervical Vertebrae - metabolism; Classical Mechanics; Computational fluid dynamics; Computer Simulation; Dynamics; Flow measurement; Fluid dynamics; Humans; Hydrodynamics; In vitro testing; Magnetic Resonance Imaging; Mathematical models; Models, Neurological; Regression analysis; Spatial distribution; Spine; Phantom experiment; Cerebrospinal fluid; Magnetic resonance imaging; Computational fluid dynamics; 4D Flow measurement
• DOI: 10.1007/s10439-016-1602-x
• ISSN: 0090-6964; 1573-9686

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.