Incidence of Keratoconus in Refractive Surgery Population of Vojvodina - Single Center Study

Abstract

Introduction: Keratoconus (KCN) is known to affect all ethnicities but its incidence exhibits geographical variability plausibly due to subclinical forms of the disease, differences in diagnostic methods and criteria, or differences in genetic variations in populations. Aim: To examine the prevalence of keratoconus among the refractive surgery population of Vojvodina, who underwent refractive surgery screening at Eye Clinic Svjetlost Novi Sad, Serbia from September 2018 to September 2019. This is a single-center study. Methods: Retrospective analysis of 876 patients who presented for refractive surgery evaluation. Corneal tomographers represent the gold standard in the detection and classification of corneal ectatic diseases and screening is an essential part of the preoperative diagnostics before any refractive surgery. The corneal tomographer used in this study was a Scheimpflug imaging device (Pentacam AXL, Oculus Optikgeräte GmbH, Wetzlar, Germany). The device was realigned before each measurement. Results: Out of a total number of patients, 619 (70,7%) were candidates for corneal refractive surgery procedure, and 257 patients (29.3%) were not. Out of 257 patients that were not candidates for the procedure 157 (61,0%) patients had thin corneas, high myopia/hypermetropia or had some retinal disease; 75 patients (29,1) were keratoconus suspect and 25 patients (9,7%) had keratoconus. KCN patients had a mean age of 29.5 ± 7.7 years, 18 patients (72.0%) were male and 7 patients were female (28%). Conclusion: The most cited annual incidence of KCN is 2 approximately 1 per 2,000. Recent data from the biggest Netherland study revealed many different epidemiological results which deprive keratoconus of the community of rare diseases. The incidence of keratoconus in Vojvodina refractive surgery population presented in our Clinic was 2.9%.

Prevalence of Keratoconus in Refractive Surgery Practice Population in North Macedonia

“…Our study found that males had a 4 times greater chance of being diagnosed with KC than females, and the prevalence values of 71.7% for males and 28.3% for females are very similar to the results of a more recent study by Bejdic et al [19].…”

“…We are aware of only two other studies on refractive surgery populations in the region around N. Macedonia. The prevalence of KC in these studies was 2.9% and 8.5% respectively, values much lower compared with the current study [19,20]. However, the design of these other studies did not consider ethnicity and the age ranges in the sample groups were limited.…”

Keratoconus detected by corneal topography in patients seeking refractive surgery in Jazan region, Saudi Arabia: A retrospective cross-sectional study

“…Our study shows 3% manifest unilateral KC, 18.72% manifest bilateral KC, and 16.48% suspected unilateral KC, 9.36% suspected bilateral KC in a relatively large sample of 534 patients, in contrast to published studies in our geographical area (Egypt& Africa) [ 13 ]. Ahmed et al [ 3 ] found a prevalence of 7% in a 100 individual sample, Elbedewy et al [ 5 ] reported a prevalence of 1.2% in a large sample of 8124, and Saro et al [ 6 ] of 17.5% in a sample size of 1202. We also found that k max, location of thinnest section, asymmetry, anterior elevation map, posterior elevation map, and Kc diagram are good indices of manifested KC as there are significant differences between normal and manifested KC (p-value < 0.001), In contrast, Elbe dew et al [ 4 ] found no significant difference concerning regions of the cornea with varying thickness between normal and manifest KC, Sidky et al [ 7 ] found a significant difference in the anterior and posterior elevation map between normal, suspected and manifested KC.…”

“…Keratoconus is an idiopathic chronic non-inflammatory corneal disease that presents with degeneration of the eye structure within the cornea, thereby shrinking and thinning of the eyeball [ [1] , [2] , [3] , [4] ]. Normally, the disorder begins at a tender age and may last longer, extending to 40 years of age.…”

“…Incidentally, poor research methods in different medical facilities and poor diagnosis and treatment methods perpetuate its prevalence and spread. Such cases explain the tendency to infect [ 2 , 3 , 5 , 6 ]. Research on the keratoconus disorder and its prevalence is challenging because of the geographical distribution of patients and their differences limiting the scope of their studies.…”