Bilateral Symmetry in Central Retinal Blood Vessels

Symmetry can be defined as uniformity, equivalence or exact similarity of two parts divided along an axis. While our left and right eyes clearly have a high degree of external bilateral symmetry, it is less obvious to what degree they have internal bilateral symmetry. This is especially true for central retinal blood vessels (CRBVs) which are responsible for supplying blood to retinas and also can be used as a strong biometric. In this paper, we study whether CRBVs of the left and right retinas possess strong enough bilateral symmetry so that we reliably tell whether a pair of CRBVs of the left and right retinas belongs to a single person. We evaluate and analyse the performance of both human and neural network based bilateral CRBVs verification. By experimenting on a large publicly available data set, we confirm that CRBVs have bilateral symmetry to some extent.