Scalability and severity of keratoconus in children.

PURPOSE: To assess the severity of keratoconus at diagnosis and its scalability over a period of 2 years in children compared to adults. DESIGN: A retrospective monocentric study was conducted in the National Reference Center for Keratoconus, Bordeaux (France), between October 1997 and November 2010. METHODS: In total, 216 patients were studied, comprising 49 patients (22.7%) aged <= 15 and 167 patients (77.3%) aged >= 27 years at diagnosis, who were seen within 2 years of diagnosis. Severity at diagnosis was assessed using Krumeich's classification, and the scalability criteria of the US Food and Drug Administration (2010) were used. Student t tests and chi(2) tests were performed to compare the 2 groups. RESULTS: Keratoconus in children was significantly more severe at diagnosis, with 27.8% being stage 4 vs 7.8% of adults (P < .0001). In addition, ophthalmoscopic signs were more frequent in children (42.9% vs 29.5%, P = .05), while mean values of maximum, average, and minimum keratometry as well as simulated keratometric astigmatism were higher (P < .0001, P = .0002, P = .0005, and P = .001, respectively). After diagnosis, keratoconus did not evolve more frequently in children. However, in the case of progression, keratoconus evolved faster in children, with significant differences in the spherical equivalent and maximum and minimum keratometry (P = .03, P = .02, P = .04, respectively). CONCLUSION: At diagnosis, keratoconus is often more advanced in children than in adults, with faster disease progression. Early detection and close monitoring are therefore crucial in young patients. (Am J Ophthalmol 2012;154:56-62. (C) 2012 by Elsevier Inc. All rights reserved.)