PREVALENCE OF KERATOCONUS IN PATIENT COMING FOR LASIK FOR CORRECTION OF MYOPIA OR MYOPIC ASTIGMATISM

Abstract

Background: Keratoconus (KC) is a corneal collagen disorder in which the central portion of the cornea becomes thinner and bulges forward in a cone-shaped fashion resulting in myopia, irregular astigmatism, and eventually visual impairment. Objective: Use of Pentacam topography to detect the prevalence of keratoconus and keratoconus suspect in patients coming for LASIK for correction of myopia and myopic astigmatism. Patients and methods: A retrospective non-randomized clinical study included 1000 eyes of 500 patients coming for LASIK for correction of myopia and myopic astigmatism. All patients had undergone full ophthalmic history, history of ocular surgeries, complete ophthalmic examination (visual acuity, uncorrected visual acuity (UCVA) & best corrected visual acuity (BCVA), anterior segment examination using Slit-lamp biomicroscopy, intraocular pressure (IOP) measurement by applanation tonometry and fundus examination. In this retrospective clinical study, data from Pentacam (Allegro Oculyzer) such as K readings, corneal thickness, thinnest location and cylinder was retrieved from patient’s records coming for LASIK in the period from August 2018 to July 2019 to detect keratoconus and keratoconus suspect. Results: In our study, there was high prevalence of keratoconus. It was 6.6 %, which was more than the commonly cited figures of (0.05–0.23%) for western countries. Conclusion: This study showed that the prevalence of keratoconus in patients seeking refractive surgery was 6, 6 % and the incidence of keratoconus suspect was 2, 6 %, this high incidence of keratoconus in these sample groups reflects the high incidence of keratoconus in the general population of Middle East countries compared with the western countries.