Audio frequency in vivo optical coherence elastography

Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, Crawley, Western Australia, Australia.
Physics in Medicine and Biology (Impact Factor: 2.76). 06/2009; 54(10):3129-39. DOI: 10.1088/0031-9155/54/10/011
Source: PubMed


We present a new approach to optical coherence elastography (OCE), which probes the local elastic properties of tissue by using optical coherence tomography to measure the effect of an applied stimulus in the audio frequency range. We describe the approach, based on analysis of the Bessel frequency spectrum of the interferometric signal detected from scatterers undergoing periodic motion in response to an applied stimulus. We present quantitative results of sub-micron excitation at 820 Hz in a layered phantom and the first such measurements in human skin in vivo.

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