Fig. 4
From: Reverberant 3D optical coherence elastography maps the elasticity of individual corneal layers
Elasticity characterization of layers in ex vivo porcine cornea using Rev3D-OCE. Rev3D-OCE results in ex vivo porcine cornea using a 2 kHz sinusoidal steady-state excitation and a spectral domain PhS-OCT system. a Acquired B-mode 3D volume, and particle velocity reverberant volume of cornea are shown in left and right side, respectively. In the left side of (b), a particle velocity frame is extracted at the cornea epithelium in (a) and compensated for the cornea curvature. Colormap represents particle velocity in arbitrary units as indicated in the colorbar in (a). The average auto-correlation curve (N = 360 curves) taken along radial cuts of the 2D auto-correlation plot (2 × 2 mm2 window size) covering 360 degrees was fitted to Eq. (2) and shown in the right side. Mean ± SE. Then, estimations of local wavenumber (\(k^{\ast}\)), and, therefore, shear wave speed (cs) using cs = ω0/\(k^{\ast}\), were calculated for all depths from the top (epithelium) to bottom (endothelium) layers of cornea. c Average depth-dependent shear wave speed profile of cornea and how it correlates with (1) structural information from the B-mode intensity image (colorbar as in (a)) of the same cornea sample, and (2) the anatomical description of some of the corneal layers. d 2D shear wave speed map superimposed on a B-mode structural image of the cornea
