Patient: 38 years of age, male, BCVA 0.6 at OD, 1.0 at OS, Autoref RA error, LA -0.5-0.5/84. Pachymetry OD 501 µm, OS 521 µm; topography OD AveK 48,7 dpt, 4.77 cyl, SRI 1.28, SAI 3.01, OS AveK 41,6 dpt, SRI 0.01, SAI 0.40 Ocular medical history: Exotropy of OD, BCVA with CL 0.8 at OD;. Vision improved from 0.6 to 0.8 with wear of contact lenses. General Medical History: empty Main complaint: decrease of vision at OD, glasses showed no improvement of vision at OD. Purpose: to show unilateral keratoconus suspect without any slit-lamp findings causing decreased vision. Methods: Colour Photography, Tomey Topography. Findings: Colour Slit Lamp Photography: no visible corneal stromal thinning, no conical protrusion of the cornea at the apex, no Fleischer ring, no Vogt striae, and no anterior corneal stromal scar. Corneal topography: showing an area of inferior steepening combined with an oblique cylinder >4 diopters and steep keratometric curvature greater than 47 D. Discussion: Corneal topography pattern recognition combined with quantitative diagnostic indices is useful for the screening of keratoconus (KC). KC is a noninflammatory progressive corneal disease characterized by localized conical protrusion, apical thinning, irregular astigmatism, and central scarring in the cornea. Keratoconus and other forms of corneal ectasias may be considered as a spectrum of primary corneal ectasia. The prevalence of KC is approximately one per 2,000 in the general population. Lim et al. (1) characterized keratoconus suspect (1) by corneal topography showing an area of central, inferior, or superior steepening combined with any of the following: oblique cylinder >1.5 diopters (D); steep keratometric curvature greater than 47 D, or central corneal thickness less than 500 μm, but without any slit-lamp findings. Literature: (1) Lim L, Wei RH, Chan WK, Tan DT. Evaluation of keratoconus in Asians: role of Orbscan II and Tomey TMS-2 corneal topography. Am J Ophthalmol. 2007 Mar;143(3):390-400.