Methodology: SD-OCT corneal scans of 20 eyes with keratoconus (group 1) and 20 healthy eyes with > 2 diopters (D) of corneal astigmatism as controls (group 2) are studied. Keratoconus patients referred to the Eye Dpt. of the University Hospital North Norway for CXL (Corneal collagen cross-linking)- treatment and healthy subjects seeking preoperative evaluation for refractive surgery at SynsLaser® Kirurgi AS Tromsø clinic are examined by corneal SD-OCT as a part of their routine examination. Analysis of their SD-OCT corneal scans is used for the purpose of this study.Two cross-sectional meridional corneal profiles (along steepest and flattest meridians, located by a Scheimpflug-based corneal topography) for each individual are obtained by using a RTVue100® (Optovue Inc. Fremont, California, USA), 26000-Hz SD-OCT across the central 6mm diameter of the cornea.