Related Experiment Video
Updated: Jul 30, 2025
Blood Flow Imaging with Ultrafast Doppler
Published on: October 14, 2020
Precise evaluation of blood flow patterns in human carotid bifurcation based on high-frame-rate vector flow imaging
Shaofu Hong1, Yinghui Dong1, Di Song1
1Department of Ultrasound, Shenzhen People's Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, Guangdong, China.
Insights
High-frame-rate vector flow imaging (HiFR-VFI) reliably detects complex blood flow in the carotid bifurcation, outperforming traditional color Doppler. This advanced ultrasound technique offers quantitative turbulence measurement for assessing arterial disease.
Area of Science:
- Medical Imaging
- Cardiovascular Ultrasound
- Hemodynamics
Background:
- Carotid bifurcation (CB) assessment is crucial for cardiovascular health.
- Traditional ultrasound methods like color Doppler flow imaging (CDFI) have limitations in precisely characterizing complex flow patterns.
- High-frame-rate vector flow imaging (HiFR-VFI) offers potential for more detailed hemodynamic evaluation.
Purpose of the Study:
- To compare the feasibility of HiFR-VFI against CDFI for evaluating flow characteristics in the carotid bifurcation of healthy adults.
- To assess the accuracy and capabilities of HiFR-VFI in identifying and quantifying non-laminar and complex blood flow patterns.
Main Methods:
- Forty-three healthy volunteers underwent carotid bifurcation flow assessment using both HiFR-VFI and CDFI.
- Flow patterns were classified based on streamlines visualized by HiFR-VFI.
- A novel turbulence index (Tur-value) was quantitatively measured, and interobserver agreement was evaluated.
Main Results:
- HiFR-VFI identified non-laminar flow in 18.6% of cases where CDFI did not.
- HiFR-VFI revealed a significantly larger extension of complex flow (0.37 cm² vs 0.22 cm²).
- Quantitative analysis showed distinct Tur-values for different flow patterns (laminar, rotational, reversed, complex), with complex flow exhibiting the highest turbulence.
Conclusions:
- HiFR-VFI reliably characterizes complex hemodynamics in the carotid bifurcation.
- Quantitative turbulence measurement using HiFR-VFI provides valuable insights.
- HiFR-VFI shows promise as an auxiliary diagnostic tool for atherosclerotic arterial disease assessment.
Purpose:
To investigate the feasibility of high-frame-rate vector flow imaging (HiFR-VFI) compared to ultrasound color Doppler flow imaging (CDFI) for precisely evaluating flow characteristics in the carotid bifurcation (CB) of presumed healthy adults.
Methods:
Forty-three volunteers were assessed for flow characteristics and their extensions using HiFR-VFI and CDFI in CBs. The flow patterns were classified according to the streamlines in HiFR-VFI and quantitatively measured using an innovative turbulence index (Tur-value). Interobserver agreement was also assessed.
Results:
HiFR-VFI was consistent with CDFI in detecting laminar and nonlaminar flow in 81.4% of the cases; however, in 18.6% of the cases, only HiFR-VFI identified the nonlaminar flow. HiFR-VFI showed a larger extension of complex flow (0.37 ± 0.26 cm2 ) compared to CDFI (0.22 ± 0.21 cm2 ; p < 0.05). The flow patterns were classified into four types: 3 type-I (laminar flow), 35 type-II (rotational flow), 27 type-III (reversed flow), and 5 type-IV (complex flow). The Tur-value of type-IV (50.03 ± 14.97)% is larger than type-III (44.57 ± 8.89)%, type-II (16.30 ± 8.16)%, and type-I (1.48 ± 1.43)% (p < 0.05). Two radiologists demonstrated almost perfect interobserver agreement on recognizing the change of streamlines (κ = 0.81, p < 0.001). The intraclass correlation coefficient of the Tur-value was 0.98.
Conclusion:
HiFR-VFI can reliably characterize complex hemodynamics with quantitative turbulence measurement and may be an auxiliary diagnostic tool for assessing atherosclerotic arterial disease.
