We demonstrate a novel method for noninvasive quantification of tissue biomechanical properties in 3D using phase-stabilized swept source optical coherence elastography (PhS-SSOCE). A focused air-pulse delivery system induces an elastic wave, which is then recorded by the PhS-SSOCE system. By calculating the velocity in all radial directions and imaging depths from the origin of the stimulation, a volumetric elasticity map was generated. Utilizing the high spatial sensitivity of PhS-SSOCE, the force applied on the surface of the cornea and subsequent induced deformation amplitude was minimal, thus preserving the structure and function of delicate ocular tissues such as the cornea and sclera. The results show that this noninvasive method for elasticity assessment can provide a volumetric mapping of elasticity and can differentiate untreated and UV-induced collagen cross-linked (CXL) corneas. As expected, the elastic wave velocity and subsequent Young’s modulus was significantly higher in the CXL cornea as compared to the untreated cornea, indicating a substantial increase in corneal stiffness after the CXL treatment.

Date Published: 20 March 2015
PDF: 8 pages
Proc. SPIE 9307, Ophthalmic Technologies XXV, 930718 (20 March 2015); doi: 10.1117/12.2080066

Published in SPIE Proceedings Vol. 9307:
Ophthalmic Technologies XXV
Fabrice Manns; Per G. Söderberg; Arthur Ho, Editor(s)