Prevalência do ceratocone superior em pacientes com ectasia corneana: análise de uma série de casos

Abstract

ABSTRACT Objective: To evaluate the prevalence of superior keratoconus in patients with corneal ectasia. Methods: This retrospective observational study defined suspected cases of superior keratoconus using criteria including parameters of superior asymmetric and/or irregular topographic astigmatism, thinnest point of corneal pachymetry less than 500 µm, maximum keratometry above 47.2 D, or maximum posterior elevation greater than or equal to 18 µm located in the upper half of the cornea. Statistical tests were performed with the aid of software and a significance level of 5%. Results: Of the six analyzed participants with suspected superior keratoconus, all presented with superior asymmetric topographic astigmatism and a mean age of 23.17 ± 10.94, with equal gender distribution. The prevalence of suspected superior keratoconus was 2 in 100 cases of corneal ectasia. Although Kmax showed a negative correlation tendency with maximum posterior elevation and the D index, there was no statistical significance. Conclusion: The results suggest that superior keratoconus is a rare condition that may be related to superior asymmetric topographic astigmatism and risk factors such as allergies and ocular itching. However, more studies are needed to understand its mechanisms and to identify effective diagnostic, preventive, and treatment measures.