Title: Spatially-resolved Brillouin spectroscopy reveals biomechanical changes in early ectatic corneal disease and post-crosslinking in vivo,
Abstract: Mounting evidence connects the biomechanical properties of tissues to the
development of eye diseases such as keratoconus, a common disease in which the
cornea thins and bulges into a conical shape. However, measuring biomechanical
changes in vivo with sufficient sensitivity for disease detection has proved
challenging. Here, we present a first large-scale study (~200 subjects,
including normal and keratoconus patients) using Brillouin light-scattering
microscopy to measure longitudinal modulus in corneal tissues with high
sensitivity and spatial resolution. Our results in vivo provide evidence of
biomechanical inhomogeneity at the onset of keratoconus and suggest that
biomechanical asymmetry between the left and right eyes may presage disease
development. We additionally measure the stiffening effect of corneal
crosslinking treatment in vivo for the first time. Our results demonstrate the
promise of Brillouin microscopy for diagnosis and treatment of keratoconus, and
potentially other diseases.