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Updated: Apr 12, 2026
05:57
Blood Flow Imaging with Ultrafast Doppler
Published on: October 14, 2020
8.8K
Effects of reverberations and clutter filtering in pulsed Doppler using sparse sequences
Summary
Sparse duplex ultrasound sequences can cause artifacts and bias in blood velocity estimation due to signal discontinuities and filtering issues. These effects are particularly problematic for cardiac applications, limiting the utility of these advanced ultrasound techniques.
Area of Science:
- Medical Imaging
- Ultrasound Technology
- Biomedical Engineering
Background:
- Duplex ultrasound combines B-mode imaging and Doppler velocity data.
- Conventional sequences have gaps due to interleaved transmissions.
- Sparse sequences aim to avoid gaps using nonuniformly sampled data.
Purpose of the Study:
- To investigate negative effects on velocity estimation with nonuniformly sampled duplex ultrasound data.
- To quantify signal discontinuities and clutter filtering artifacts.
- To analyze the suitability of sparse sequences for blood velocity estimation.
Main Methods:
- Analysis of signal discontinuities caused by long reverberation times after B-mode interruptions.
- Frequency analysis to identify artifacts and bias in velocity spectra from filtered nonuniformly sampled Doppler data.
- Evaluation of three sparse duplex sequences using in vitro and in vivo data.
Main Results:
- Long reverberation times create signal discontinuities in stationary clutter.
- Clutter filtering of nonuniformly sampled data introduces velocity spectrum artifacts and bias.
- Sparse sequences are not recommended for cardiac applications due to reverberation.
- Regression filters cause significant artifacts in pulsed wave Doppler but less in color Doppler.
Conclusions:
- Nonuniform sampling in sparse duplex ultrasound sequences introduces significant challenges for accurate blood velocity estimation.
- The identified artifacts and biases limit the clinical application of these sequences, especially in cardiac imaging.
- Further research may be needed to mitigate these effects for broader adoption.
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