Adaptive Clutter Filtering in Ultrasound Doppler Imaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional ultrasound systems face challenges in effectively filtering out clutter signals from blood flow signals due to their high amplitude, which degrades image quality and limits the performance of high pass filters, especially when applying identical filters across entire regions of interest.
Innovation Solution
An adaptive clutter filtering method is implemented in an ultrasound system, where filter coefficients such as cutoff frequency and stopband attenuation are adjusted for each pixel based on the characteristics of the clutter signal, allowing for tailored filtering to enhance the removal of clutter while preserving blood flow signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a high pass filter is designed to remove clutter signals, then clutter filtering performance is improved, but the complexity of filter design and selection increases
Solution Approach 1:
The patent applies parameter changes by dynamically adjusting filter coefficients (cutoff frequency, stopband attenuation) based on the measured power ratio between clutter and blood flow signals. Instead of using a fixed filter design, the system modifies filter parameters in real-time according to the actual signal characteristics, thereby achieving high clutter filtering performance without requiring multiple complex filter designs.
2Device complexity
If an identical clutter filter is applied to entire regions of interest, then device complexity is reduced, but image quality degradation occurs in different regions
Solution Approach 1:
The patent implements local quality by dividing the region of interest into multiple regions and applying different filter coefficients to each region based on local signal characteristics. Specifically, the system calculates power ratios separately for each region and adjusts filter parameters locally, ensuring optimal clutter filtering for each area while maintaining reasonable system complexity through automated regional processing.
3Measurement precision
If clutter filter coefficients are adjusted for each pixel, then clutter removal effectiveness is improved, but processing time and computational load increase
Solution Approach 1:
The patent applies segmentation by dividing the region of interest into a limited number of regions (not individual pixels) and calculating a single power ratio and filter coefficient set for each region. This approach maintains clutter removal effectiveness by adapting filters to local characteristics while significantly reducing computational load compared to pixel-by-pixel processing, as the system only needs to process one coefficient set per region rather than per pixel.
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
Embodiments for adaptively performing clutter filtering upon in an ultrasound system are disclosed. In one embodiment, the ultrasound system includes: an ultrasound data acquisition unit configured to transmit ultrasound signals to a target object and receive ultrasound echoes reflected from the target object to thereby acquire ultrasound data; and a processing unit configured to form a Doppler signal corresponding to each of a plurality of pixels constructing a Doppler mode image based on the ultrasound data, as well as to adjust coefficients of a clutter filter based on characteristics of the Doppler signal for each of the pixels for performing clutter filtering upon the Doppler signal.