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[1] Ophir, Jonathan, et al. "Elastography: a quantitative method for imaging the elasticity of biological tissues." Ultrasonic imaging (1991)
[2] Muthupillai, R., et al. "Magnetic resonance elastography by direct visualization of propagating acoustic strain waves." Science (1995)
Air-pulse OCE (cornea) [3]
Mechanical actuator for tissue phantom [4]
Ultrasound as wave source
(porcine retina) [5]
mm-OCE (Rat liver and chicken muscle) [6]
[3] Wang, Shang, and Kirill V. Larin. "Shear wave imaging optical coherence tomography (SWI-OCT) for ocular tissue biomechanics." Optics letters (2014)
[4] Nguyen, Thu-Mai, et al. "Shear wave pulse compression for dynamic elastogrcoherence tomography." Journal of biomedical optics (2014)
[5] Song, Shaozhen, et al. "Quantitative shear-wave optical coherence elastography with a programmable phased array ultrasound as the wave source." Optics letters (2015)
[6] Ahmad, Adeel, et al. "Magnetomotive optical coherence elastography using magnetic particles to induce mechanical waphy using phase-sensitive optical aves." Biomedical optics express (2014)
Megahertz Optical Coherence Elastography
~1.5 MHz A-scan rate
 New scanning mechanism compared to conventional
OCE
Air-pulse
Excitation
OCT Scan Path
Sample
[3] Wang, Shang, and Kirill V. Larin. "Shear wave imaging optical coherence tomography (SWI-OCT) for ocular tissue biomechanics." Optics letters (2014)
Air-pulse
Excitation
OCT Scan Path
Sample
 Megahertz OCE system
• ~1.5 MHz A-scan rate
• 4X Buffered FDML
• OptoRes Gmbh
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1316 nm central wavelength
100 nm bandwidth
16 µm axial resolution
Up to 160 mW of power
7.3 kHz resonant scanner
 Lorentz force excitation system
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Waveform generator
Power amplifier
Two magnets
Probe
Future work
 Improve the SNR of displacement signal;
• Electrical current
• Magnetic field
• Tissue conductivity
 Analyze tissue viscoelasticity by elastic wave dispersion
 Frequency analysis