Acoustomotive optical coherence elastography for measuring material mechanical properties

Acoustomotive optical coherence elastography (AM-OCE), a dynamic and internal excitation optical coherence elastography technique, is reported. Acoustic radiation force was used for internal mechanical excitation, and spectral-domain optical coherence tomography was used for detection. Mechanical properties of gelatin tissue phantoms were measured by AM-OCE and verified using rheometry results. Measured mechanical properties including shear moduli and shear damping parameters of the gelatin samples double when their polymer concentration increases from 3% to 4%. Spectral analysis was also performed on the acquired data, which improved the processing speed by a factor of 5 compared with a least-square fitting approach. Quantitative measurement, microscale resolution, and remote excitation are the main features of AM-OCE, which make the technique promising for measuring biomechanical properties.