3D Wiener Filtering to Reduce Reverberations in Ultrasound Image Sequences
One of the most frequently occuring artifacts in ultrasound imaging is reverberations. These are multiple reflection echoes that result in ghost echoes in the ultrasound image. A method for reducing these unwanted artifacts using a three-dimensional
(3D) Wiener filter is presented. The Wiener filter is a global filter and produces an estimate of the uncorrupted signal by minimizing the mean square error between the estimate and the uncorrupted signal in a statistical sense.
The procedure works as follows: In a graphic interface the operator is displayed an image sequence. The operator marks two areas in one of the images; one area which contains a typical reverberation artifact, and one area free from artifact. Using these areas to produce noise and signal estimates, a Wiener filter is created and applied to the sequence.
The 3D Wiener filters display excellent selection capabilities, and the developed method significantly reduces the magnitude of the reverberation artifact in the tested sequences.
KeywordsWiener Filter Noise Power Spectrum Transducer Surface Medical Ultrasound Image Reverberation Artifact
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