Denoising performance of modified dual-tree complex wavelet transform for processing quadrature embolic Doppler
Gorkem Serbes1, Nizamettin Aydin
1Biomedical Engineering Department, Bahcesehir University, Çırağan Caddesi, Osmanpaşa Mektebi Sokak No: 4-6, 34353, Beşiktaş, Istanbul, Turkey, gorkem.serbes@bahcesehir.edu.tr.
Medical & Biological Engineering & Computing
|September 20, 2013
Summary
Modified dual-tree complex wavelet transform effectively denoises embolic Doppler ultrasound signals. This method offers improved performance over discrete wavelet transform and is computationally efficient compared to dual-tree complex wavelet transform for stroke diagnosis.
Area of Science:
- Biomedical Engineering
- Signal Processing
- Medical Imaging
Background:
- Embolic Doppler ultrasound signals are crucial for stroke diagnosis.
- Embolus detection relies on the embolic signal-to-background ratio, often enhanced by denoising.
- Conventional discrete wavelet transform (DWT) lacks shift invariance for signal denoising.
Purpose of the Study:
- To evaluate the denoising performance of the modified dual-tree complex wavelet transform (MDCT) for embolic signals.
- To compare MDCT with DWT and dual-tree complex wavelet transform (DT-CWT).
- To assess MDCT's computational efficiency and denoising capabilities.
Main Methods:
- Simulated and real quadrature signals from stroke-prone patients were used.
- Denoising was performed using DWT, DT-CWT, and MDCT.
- Performance was quantitatively evaluated based on denoising effectiveness and computational cost.
Main Results:
- MDCT demonstrated superior denoising performance compared to DWT at similar computational complexity.
- MDCT achieved performance comparable to DT-CWT but with significantly reduced computational cost (nearly half).
- The study validates MDCT as an efficient denoising technique for embolic signals.
Conclusions:
- Modified dual-tree complex wavelet transform is a highly effective and computationally efficient method for denoising embolic Doppler ultrasound signals.
- MDCT offers a promising advancement for improving embolus detection accuracy in stroke diagnosis.
- This technique balances performance and computational load, making it suitable for clinical applications.
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