Local comparison of cup to disc ratio in right and left eyes based on fusion of color fundus images and OCT B-scans

•We investigate symmetry between 2 eyes by calculating local cup to disc ratio (CDR) from each B-scan.•B-scans of eyes should be aligned, but the fovea-ONH axes (raphae) in OCT data are not available.•At first, left and right fundus images are aligned according to their automatically detected raphae.•Then OCTs are registered to corresponding fundus images based on curvelet-based extracted vessels.•CDRs are compared by ridgelet-based analysis of Bscans resulting in a new biomarker: Volumetric CDR.