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Updated: Aug 25, 2025
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Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section
Published on: July 19, 2016
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Velocity vector comparison between vector flow imaging and computational fluid dynamics in the carotid bifurcation
Sofia Poloni1, Michela Bozzetto1, Yigang Du2
1Department of Biomedical Engineering, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy.
Ultrasonics
|October 16, 2022
Summary
High-frame rate Vector Flow Imaging (HiFR-VFI) accurately visualizes blood flow in carotid bifurcations. This non-invasive technique shows significant agreement with computational fluid dynamics, aiding in identifying vulnerable plaques.
Area of Science:
- Biomedical Engineering
- Cardiovascular Research
- Medical Imaging
Background:
- Local hemodynamic conditions, including low and oscillating wall shear stresses, are implicated in vascular atherosclerotic lesion development.
- Investigating carotid bifurcation flow fields can aid in early identification of vulnerable atherosclerotic plaques.
- Novel non-invasive imaging tools are crucial for detecting disturbed and recirculating blood flow in clinical practice.
Purpose of the Study:
- To validate the high-frame rate vector flow imaging (HiFR-VFI) technique in various carotid bifurcation locations.
- To compare HiFR-VFI measurements with computational fluid dynamics (CFD) simulations.
Main Methods:
- The study involved eight carotid bifurcations.
- HiFR-VFI was employed for angle-independent assessment of blood flow velocity and multidimensional flow vector visualization.
- CFD simulations were used as a reference for validation.
Main Results:
- HiFR-VFI successfully identified regions of laminar flow, recirculation, and unsteady flow in all tested carotid bifurcations.
- A statistically significant agreement was found between HiFR-VFI and CFD for both velocity vector magnitude (R=0.85) and direction (R=0.74).
Conclusions:
- HiFR-VFI is a validated technique for advanced visualization of velocity fields in large arteries.
- The technique holds significant potential for clinical research in identifying flow recirculation and low/oscillating velocity gradients near vessel walls.
- HiFR-VFI may enhance the investigation of local hemodynamics in vascular pathologies and the assessment of treatment effects.
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