Key result
CFD predicts ~7 times higher absolute wall shear stress than 4D-flow MRI despite similar distributions.
Why the study?
Does computational fluid dynamics provide more accurate absolute quantification of wall shear stress compared to 4D-flow MRI in aortic coarctation?
Does computational fluid dynamics provide more accurate absolute quantification of wall shear stress compared to 4D-flow MRI in aortic coarctation?
While 4D-flow MRI can qualitatively identify regions of altered wall shear stress in aortic coarctation, computational fluid dynamics is required for accurate absolute quantification due to MRI's limited spatial resolution.
In this study, we analyzed turbulent flows through a phantom (a 180[Formula: see text] bend with narrowing) at peak systole and a patient-specific coarctation of the aorta (CoA), with a pulsating flow, using magnetic resonance imaging (MRI) and computational fluid dynamics (CFD). For MRI, a 4D-flow MRI is performed using a 3T scanner. For CFD, the standard [Formula: see text], shear stress transport [Formula: see text], and Reynolds stress (RSM) models are applied. A good agreement between measured and simulated velocity is obtained for the phantom, especially for CFD with RSM. The wall shear stress (WSS) shows significant differences between CFD and MRI in absolute values, due to the limited near-wall resolution of MRI. However, normalized WSS shows qualitatively very similar distributions of the local values between MRI and CFD. Finally, a direct comparison between in vivo 4D-flow MRI and CFD with the RSM turbulence model is performed in the CoA. MRI can properly identify regions with locally elevated or suppressed WSS. If the exact values of the WSS are necessary, CFD is the preferred method. For future applications, we recommend the use of the combined MRI/CFD method for analysis and evaluation of the local flow patterns and WSS in the aorta.
No takes yet. Share an insight, caveat, or question.
Perinajová et al. (2021) studied Aortic coarctation (n=1). Computational Fluid Dynamics (CFD) vs. 4D-flow MRI was evaluated on Wall shear stress (WSS). Computational fluid dynamics predicted significantly higher absolute wall shear stress values than 4D-flow MRI (mean 15.06 Pa vs 2.12 Pa in vivo), though both methods showed qualitatively similar local distributions.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: