Multifrequency vibro-acoustography.

Matthew W Urban; Glauber T Silva; Mostafa Fatemi; James F Greenleaf

doi:10.1109/tmi.2006.882142

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PubMed · 17024832

Multifrequency vibro-acoustography.

Matthew W Urban·Glauber T Silva·Mostafa Fatemi·James F Greenleaf

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Abstract

Elasticity imaging is a burgeoning medical imaging field. Many methods have been proposed that impart a force to tissue and measure the mechanical response. One method, vibro-acoustography, uses the ultrasound radiation force to harmonically vibrate tissue and measure the resulting acoustic emission field with a nearby hydrophone. Another method, vibrometry, uses the ultrasound radiation force accompanied with a measurement of the resulting velocity or displacement of the vibrating tissue or object has also been used for different applications. An extension of the vibro-acoustography method using a multifrequency stress field to vibrate an object is described. The objective of this paper is to present the image formation theory for multifrequency vibro-acoustography. We show that the number of low-frequency components created by this multifrequency method scales with the square of the number of ultrasound sources used. We provide experimental validation of the point-spread function of the multifrequency stress field and show examples of both vibrometry and vibro-acoustography imaging applications. This method holds the potential for a large gain of information with no increase in scanning time compared to conventional vibro-acoustography systems.

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Acoustics Algorithms Breast Neoplasms Computer Simulation Humans Image Enhancement Image Interpretation, Computer-Assisted Information Storage and Retrieval Microscopy, Acoustic Models, Biological Phantoms, Imaging Reproducibility of Results Sensitivity and Specificity Ultrasonography, Mammary Vibration Evaluation Study Journal Article Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't

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Matthew W Urban, Glauber T Silva, Mostafa Fatemi, James F Greenleaf. 2006. Multifrequency vibro-acoustography.. https://doi.org/10.1109/tmi.2006.882142

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