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Shear modulus imaging by direct visualization of propagating shear waves with phase-sensitive optical coherence tomography.

ABSTRACT: We propose an integrated method combining low-frequency mechanics with optical imaging to map the shear modulus within the biological tissue. Induced shear wave propagating in tissue is tracked in space and time using phase-sensitive optical coherence tomography (PhS-OCT). Local estimates of the shear-wave speed obtained from tracking results can image the local shear modulus. A PhS-OCT system remotely records depth-resolved, dynamic mechanical waves at an equivalent frame rate of ?47??kHz with the high spatial resolution. The proposed method was validated by examining tissue-mimicking phantoms made of agar and light scattering material. Results demonstrate that the shear wave imaging can accurately map the elastic moduli of these phantoms.

SUBMITTER: Song S

PROVIDER: S-EPMC4019419 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature

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Shear modulus imaging by direct visualization of propagating shear waves with phase-sensitive optical coherence tomography.

Song Shaozhen S Huang Zhihong Z Nguyen Thu-Mai TM Wong Emily Y EY Arnal Bastien B O'Donnell Matthew M Wang Ruikang K RK

Journal of biomedical optics 20131201 12

We propose an integrated method combining low-frequency mechanics with optical imaging to map the shear modulus within the biological tissue. Induced shear wave propagating in tissue is tracked in space and time using phase-sensitive optical coherence tomography (PhS-OCT). Local estimates of the shear-wave speed obtained from tracking results can image the local shear modulus. A PhS-OCT system remotely records depth-resolved, dynamic mechanical waves at an equivalent frame rate of ∼47 kHz with ...[more]

PMID: 24213539

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