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Updated: Jun 5, 2026
05:57
Blood Flow Imaging with Ultrafast Doppler
Published on: October 14, 2020
Comparison of pulse subtraction Doppler and pulse inversion Doppler
Veronique Mahue1, Jean Martial Mari, Robert J Eckersley
1Department of Bioengineering, Imperial College London, London, UK.
Summary
A new pulse subtraction imaging (PSD) Doppler technique effectively separates microbubble and tissue motion. While pulse inversion Doppler (PID) offers higher contrast-to-tissue ratios in some conditions, PSD uses less energy, making it less disruptive for targeted imaging applications.
Area of Science:
- Medical Imaging
- Ultrasound Technology
- Biomedical Engineering
Background:
- Contrast-enhanced ultrasound (CEUS) utilizes microbubbles for enhanced visualization.
- Distinguishing microbubble motion from tissue motion is crucial for targeted imaging and diagnostics.
- Existing Doppler techniques face challenges in separating these distinct motion types.
Purpose of the Study:
- To introduce and evaluate a novel pulse subtraction imaging (PSD) Doppler technique.
- To compare the performance of PSD against pulse inversion Doppler (PID).
- To assess the utility of PSD in differentiating microbubble and tissue motion for targeted imaging.
Main Methods:
- Development of a new Doppler technique based on pulse subtraction imaging (PSD).
- Comparison of PSD with pulse inversion Doppler (PID) using both simulations and experimental data.
- Evaluation of contrast-to-tissue ratio (CTR) at different mechanical indices (MI) and frequencies.
- Analysis of Doppler processing at fundamental and harmonic frequencies.
Main Results:
- PSD demonstrated the ability to differentiate microbubble motion from tissue motion.
- At a low MI (0.1) and fundamental frequency, PSD achieved a 3.3 times higher CTR than PID.
- At the harmonic frequency, PID showed a 3.1 times higher CTR than PSD.
- Under optimal conditions, PID achieved up to 1.9 times higher CTR than PSD, with CTRs increasing with MI for both.
Conclusions:
- PSD is a viable technique for separating microbubble and tissue motion, particularly beneficial for targeted imaging.
- PSD offers advantages in reduced energy transmission, making it less disruptive compared to PID.
- The choice between PSD and PID depends on specific imaging requirements, frequency, and desired contrast enhancement.
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