The cornea is a transparent dome-shaped tissue at the front of the eye that allows light rays to enter the eye. The mechanical properties of the cornea play an important role in maintaining its stability and optical function. The loss of corneal structural integrity because of ophthalmic diseases such as keratoconus and ectasia leads to significant bulging and may cause severe visual impairment including blindness. Corneal collagen crosslinking using riboflavin and ultraviolet-A (UVA) light is a recent treatment procedure that restores corneal mechanics and halts the progression of irregular changes in its shape. Nevertheless, despite promising experimental and clinical data, its underlying mechanisms are still unknown. In this research, an integrated experimental and computational framework will be used to characterize the effects of the collagen crosslinking procedure on different aspects of corneal biomechanical properties. The deeper fundamental understanding of strengthening effects of this minimally invasive procedure could lead to significant improvement of its performance and effectiveness.
This project will provide novel insight into the underlying mechanisms of corneal collagen crosslinking therapy and will assess its efficacy in restoring the mechanical strength of the cornea. To this end, different in vitro experimental techniques will be used to measure the changes in the mechanical properties of corneal tissue after collagen crosslinking using riboflavin and UVA. These experiments will be complemented by a numerical finite element model based on mixture theory. From the mechanics point of view, the corneal stroma will be modelled as a composite material consisting of a ground substance and reinforcing collagen fibrils. In addition to the significant contribution of this project to the existing body of research on the cornea, its successful completion will have a broader impact and may eventually lead to new engineering design concepts. Finally, this project includes a number of educational activities. The primary objectives of these efforts are to attract students in STEM fields and train/engage both undergraduate and graduate students in biomechanics. It is expected that this project, with its blend of biology and mechanics, will motivate students to participate in engineering research by helping them better appreciate the connection between science, biology, and engineering.
