ORIGINAL PAPER Topographic typology in a consecutive series of refractive surgery candidates Seyed-Farzad Mohammadi . Vahid Mohammadzadeh . Sakineh Kadivar . Amir-Houshang Beheshtnejad . Amir Hossein Norooznezhad . Seyed-Hassan Hashemi Received: 5 May 2017 / Accepted: 26 June 2017 Ó Springer Science+Business Media B.V. 2017 Abstract Purpose The term ‘keratoconus (KC) suspect’ is used as a blanket term to refer to any deviation of virgin cornea shape toward KC features. We intend to subclassify such topographies in meaningful and informative designations. Methods Pentacam corneal topographies of 199 consecutive refractive surgery candidates (398 eyes) are examined. Features of steepness, inferior–superior asymmetry, focal steepening, thinning, and bounded anterior or posterior elevations are observed in the quad map. Scissoring on retinoscopy, loss of best spectacle-corrected visual acuity, and iron ring depo- sition were looked for. Through iterative observation and refinement of classification criteria—partly taken from the literature—all eyes were designated a specific topographic diagnosis, i.e., circumventing the usage of the expression KC ‘suspect’. Results Topographies of 308, 48, 21, 13, 6, 1, and 1 (collectively 398 eyes) were designated: normal, ‘atypical normal,’ forme fruste KC, posterior KC, subclinical/mild KC, superior KC, and pseudo–KC, respectively. Conclusion Current imaging modalities of the cor- nea and our accumulated experience in refractive science allow assignment of distinctive designations for abnormal corneal shapes along the topography spectrum. We devised and used the expressions: normal, atypical normal, forme fruste (arrested-in- complete) KC, posterior KC, subclinical (active latent) KC, superior KC, and pseudo-keratoconus. Identification of 1.5% (mild) KC highlights the importance of screening for ultraviolet cross-linkage candidacy in refractive surgery referrals. Keywords Refractive surgery Á Keratoconus Á Suspect keratoconus Á Posterior keratoconus Á Forme fruste keratoconus Á Pentacam Introduction Keratoconus (KC) is a non-inflammatory ectatic disorder characterized by progressive steepening of the cornea [1]. At the molecular level, steepening is correlated with a series of aberrant changes in the cornea including stromal thinning, displacement of iron in epithelial basement membrane, and breaches in the bowman layer [2]. KC prevalence ranges from 17.3 per 100,000 persons in Japan to strikingly high S.-F. Mohammadi Á V. Mohammadzadeh (&) Á A.-H. Beheshtnejad Á A. H. Norooznezhad Á S.-H. Hashemi Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Qazvin Square, P.O. Box 1336616351, Tehran, Iran e-mail: vmohammadzadeh1365@yahoo.com S. Kadivar Eye Research Center, Amiralmomenin Eye Hospital, Guilan University of Medical Sciences, Rasht, Iran 123 Int Ophthalmol DOI 10.1007/s10792-017-0631-2