Correction of tissue-motion effects on common-midpoint signals using reciprocal signals

Information and Communication Technologies Centre, Commonwealth Scientific and Industrial Research Organisation, Marsfield, New South Wales 2122, Australia.
The Journal of the Acoustical Society of America (Impact Factor: 1.5). 08/2012; 132(2):872-82. DOI: 10.1121/1.4730913
Source: PubMed


The near field signal redundancy algorithm for phase-aberration correction is sensitive to tissue motion because several separated transmissions are usually needed to acquire a set of common-midpoint signals. If tissues are moving significantly due to, for example, heart beats, the effects of tissue motion on common-midpoint signals need to be corrected before the phase-aberration profile can be successfully measured. Theoretical analyses in this paper show that the arrival-time difference between a pair of common-midpoint signals due to tissue motion is usually very similar to that between the pair of reciprocal signals acquired using the same two transmissions. Based on this conclusion, an algorithm for correcting tissue-motion effects on the peak position of cross-correlation functions between common-midpoint signals is proposed and initial experimental results are also presented.

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