In vivo validation of 4D flow MRI for assessing the hemodynamics of portal hypertension

The aim of this systematic review is to provide an overview of the use of Four-Dimensional Magnetic Resonance Imaging of vector blood flow (4D Flow MRI) in the abdominal veins. This study was composed according to the PRISMA guidelines 2009. The literature search was conducted in MEDLINE, Cochrane Library, EMBASE, and Web of Science. Quality assessment of the included studies was performed using the QUADAS-2 tool. The initial search yielded 781 studies and 21 studies were included. All studies successfully applied 4D Flow MRI in abdominal veins. Four-Dimensional Flow MRI was capable of discerning between healthy subjects and patients with cirrhosis and/or portal hypertension. The visual quality and inter-observer agreement of 4D Flow MRI were rated as excellent and good to excellent, respectively, and the studies utilized several different MRI data sampling strategies. By applying spiral sampling with compressed sensing to 4D Flow MRI, the blood flow of several abdominal veins could be imaged simultaneously in 18–25 s, without a significant loss of visual quality. Four-Dimensional Flow MRI might be a useful alternative to Doppler sonography for the diagnosis of cirrhosis and portal hypertension. Further clinical studies need to establish consensus regarding MRI sampling strategies in patients and healthy subjects.

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Impact of Pulmonary Venous Inflow on Cardiac Flow Simulations: Comparison with In Vivo 4D Flow MRI

Annals of Biomedical Engineering ◽

10.1007/s10439-018-02153-5 ◽

2018 ◽

Vol 47 (2) ◽

pp. 413-424 ◽

Cited By ~ 7

Author(s):

Jonas Lantz ◽

Vikas Gupta ◽

Lilian Henriksson ◽

Matts Karlsson ◽

Anders Persson ◽

...

Keyword(s):

4D Flow Mri ◽

4D Flow ◽

Flow Simulations ◽

Flow Mri

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A dual-VENC 4D Flow MRI Framework for Analysis of Subject-Specific Heterogeneous non-linear Vessel Deformation

10.31224/osf.io/spzgd ◽

2020 ◽

Author(s):

Jamie Concannon ◽

Niamh Hynes ◽

Marie McMullan ◽

Evelyn Smyth ◽

Kevin Mattheus Moerman ◽

...

Keyword(s):

In Silico ◽

Cardiac Cycle ◽

Human Aorta ◽

4D Flow Mri ◽

4D Flow ◽

Imaging Protocol ◽

Subject Specific ◽

Non Linear ◽

Flow Mri

Advancement of subject-specific in-silico medicine requires new imaging protocols tailored to specific anatomical features, paired with new constitutive model development based on structure/function relationships. In this study we develop a new dual-VENC 4D Flow MRI protocol that provides unprecedented spatial and temporal resolution of in-vivo aortic deformation. All previous dual-VENC 4D Flow MRI studies in the literature focus on an isolated segment of the aorta, which fail to capture the full spectrum of aortic heterogeneity that exists along the vessel length. The imaging protocol developed provides high sensitivity to all blood flow velocities throughout the entire cardiac cycle, overcoming the challenge of accurately measuring the highly unsteady non-uniform flow field in the aorta. Cross sectional area change, volumetric flow rate, and compliance are observed to decrease with distance from the heart, while pulse wave velocity is observed to increase. A non-linear aortic lumen pressure-area relationship is observed throughout the aorta, such that a high vessel compliance occurs during diastole, and a low vessel compliance occurs during systole. This suggests that a single value of compliance may not accurately represent vessel behaviour during a cardiac cycle in-vivo. This high-resolution MRI data provides key information on the spatial variation in non-linear aortic compliance which can significantly advance the state-of-the-art of in-silico diagnostic techniques for the human aorta.

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Assessment of turbulent blood flow and wall shear stress in aortic coarctation using image-based simulations

BioMedical Engineering OnLine ◽

10.1186/s12938-021-00921-4 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Romana Perinajová ◽

Joe F. Juffermans ◽

Jonhatan Lorenzo Mercado ◽

Jean-Paul Aben ◽

Leon Ledoux ◽

...

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Turbulent Flows ◽

Patient Specific ◽

4D Flow Mri ◽

4D Flow ◽

Local Flow ◽

Flow Mri ◽

Wall Shear

AbstractIn this study, we analyzed turbulent flows through a phantom (a 180$$^{\circ }$$ ∘ 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 $$k-\epsilon $$ k - ϵ , shear stress transport $$k-\omega $$ k - ω , 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.

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