Fast Computation of Tunnels in Corneal Collagen Structure

The collagen fiber organization plays an important role in controlling the mechanical strength of the extracellular matrix tissues and in the cornea is thought to control tissue shape and refractive power. In the case of the cornea, collagen fibers run in orthogonal directions, interweaving, branching and anastomosing, that can be imaged using second harmonic-generated signals. But the complexity of the structure makes it difficult for identifying tunnels using previous methods. In the proposed work, we apply an efficient graph based algorithm to find fundamental cycles, including both tunnels and non-tunnels. After tightening the cycle and decoupling composite cycles, we classify the resulting fundamental cycles based on their geometric properties and their relationship between each other. The utility of our tunnel computation and location algorithm is demonstrated on various example cornea structures from various animals.