Abstract

Measuring the biomechanical properties of the cornea, such as Young’s modulus is fundamental to better understand, diagnose, and monitor degenerative ocular diseases. Current clinically-available elastographic techniques for the cornea suffer from inaccuracy and low depth-resolved resolution. We studied the propagation of surface acoustic waves (SAW) generated by a piezoelectric actuator in an ex vivo porcine cornea. The phase speed of a SAW provides localized information about the shear modulus of the medium. We tracked the main peak of the SAW in space and time using a phase-sensitive optical coherence tomography system in order to estimate the local wave speed. Experiments in phantoms validate the methodology with an accuracy error < 2%. Preliminary results report elastically differentiated layers in the cornea structure, as well as a decreasing tendency of the SAW speed as depth increases, which is consistent with the collagen distribution in the cornea.

© 2016 Optical Society of America