Prevalence of Keratoconus in Refractive Surgery Population in Sohag Governorate

Document Type : Original Article

Authors

Department of Ophthalmology, Faculty of Medicine, Sohag University.

Abstract

IntroductionKeratoconus (KC) is a developmental anomaly in which the inferior or central portion of the cornea becomes thinner and bulges forward in a cone-shaped fashion as a result of non-inflammatory thinning of the corneal stroma[1, 2].                                                                                      
The disease has its usual onset at puberty and, in many cases, progresses until the third to fourth decade of life, when it usually arrests[1]. Although a large proportion of keratoconic patients can be managed with contact lenses, an average of about 20% of all keratoconic corneas require keratoplasty; some authors report markedly different surgical indication rates of 6.5 and 12 to 45%.[3-5]                         
Aim of the work: to study the prevalence of keratoconus in patients seeking refractive surgery to correct their refractive errors and to study common risk factors.
Patients and Methods: Two thousand eyes to 1202 patients (623 males and 579 females) coming for investigations for refractive surgery were randomly chosen in the period from April to October 2015. Screening –by Pentacam- was bilateral in 798 patients and unilateral in 404 patients.
Results: the resulting cases of keratoconus were 293 eyes (14.65%) of 210 patients. Of those patients, males were 117 (165 eyes) (56.25%) and females were 93 (128 eyes) (43.75%).

Keywords


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