Longitudinal shear waves for elastic characterization of tissues in optical coherence elastography
Fernando Zvietcovich1, Gary R Ge2, Humberto Mestre3
1Dept. of Electrical & Computer Engineering, University of Rochester, Rochester, NY 14627, USA.
Biomedical Optics Express
|July 31, 2019
Summary
Longitudinal shear waves (LSW) offer advanced capabilities for optical coherence elastography (OCE). This study demonstrates LSW
Area of Science:
- Biomedical Optics
- Biophysics
- Medical Imaging
Background:
- Dynamic optical coherence elastography (OCE) typically uses surface acoustic waves, limiting elasticity measurements to tissue surfaces.
- Current methods fail to capture elasticity gradients along the depth of tissues.
Purpose of the Study:
- To investigate the potential of longitudinal shear waves (LSW) for enhanced OCE.
- To explore LSW's ability to measure elasticity gradients in both axial and lateral directions.
Main Methods:
- Numerical simulations were performed to model LSW generation and propagation.
- Tissue-mimicking phantoms were used to experimentally validate LSW capabilities.
- Phase-sensitive optical coherence tomography was employed to measure LSW displacement.
Main Results:
- LSW can be generated at the tissue surface and propagate through depth.
- LSW enable simultaneous detection of elasticity gradients along axial and lateral directions.
- Successful elastography of ex vivo mouse brain tissue was achieved using LSW.
Conclusions:
- LSW show significant potential for improving OCE by measuring depth-dependent elasticity.
- This technique has implications for in vivo and in situ brain elasticity measurements.
- LSW may help correlate local elasticity changes with neurodegenerative diseases.
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