Dynamic optical coherence elastography (OCE) tracks mechanical wave propagation in the subsurface region of tissue to map its shear modulus. For bulk shear waves, the lateral resolution of the reconstructed modulus map (i.e., elastographic resolution) can approach that for OCT, typically a few tens of microns. However, skin, cornea and many other tissues are layered or bounded leading to the formation of guided mechanical waves. We performed numerical simulations and acoustic micro-tapping experiments to show that in bounded media, the elastographic resolution cannot reach the OCT structural resolution and is mainly defined by the thickness of the bounded tissue layer.
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