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Updated: Jun 20, 2026
05:57
Blood Flow Imaging with Ultrafast Doppler
Published on: October 14, 2020
In-vivo examples of flow patterns with the fast vector velocity ultrasound method
1Department of Radiology, University Hospital of Copenhagen, Denmark. lindskov@gmail.com
Ultraschall in Der Medizin (Stuttgart, Germany : 1980)
|September 19, 2009
Summary
The Plane Wave Excitation (PWE) ultrasound method visualizes complex blood flow in 2D vector velocity with high frame rates. This advanced technique reveals intricate flow patterns in vessels, surpassing conventional imaging limitations.
Area of Science:
- Medical Imaging
- Ultrasound Technology
- Fluid Dynamics
Background:
- Conventional ultrasound color flow imaging is limited by low frame rates and unidirectional velocity estimation.
- These limitations hinder detailed visualization of complex blood flow dynamics.
Purpose of the Study:
- To introduce and evaluate the Plane Wave Excitation (PWE) method for high-frame-rate 2D vector velocity estimation in ultrasound.
- To overcome the limitations of conventional ultrasound in capturing complex blood flow patterns.
Main Methods:
- PWE transmits unfocused ultrasound pulses (13 bit Barker code) from all transducer elements simultaneously.
- 2D vector velocity is determined using 2D speckle tracking between consecutive full speckle images.
- The method was implemented on the RASMUS scanner and processed on a 100 CPU Linux cluster, achieving 100 Hz frame rates.
Main Results:
- In-vivo vector velocity estimates were obtained in complex vessel geometries, including bifurcations and veins.
- Stable vortices were observed in the carotid bulb, unlike other bifurcations.
- Retrograde flow was detected in the superficial femoral artery and subclavian artery during diastole.
- Vortices formed behind venous valves, and secondary flow was present in various vessels.
Conclusions:
- The PWE ultrasound method enables detailed in-vivo visualization of complex blood flow patterns.
- This technique offers superior visualization compared to conventional color flow imaging.
- PWE advances the study of hemodynamics in intricate vascular structures.
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