Prevalence of Keratoconus in Egyptian Astigmatic Patients

Abstract

SUMMARY K eratoconus is a corneal ectatic disease characterized by non-inflammatory progressive thinning of unknown cause in which the cornea assumes a conical shape. As the cornea steepens and thins the patient experiences decrease in vision which can be mild or severe depending on the corneal tissue affected Most cases of keratoconus are sporadic. Hereditary transmission of keratoconus also had been reported. Dominant, recessive, and irregular transmission all appeared to be implicated. Detecting the cases of subclinical keratoconus always has been a challenge for ophthalmologist especially when the suggestive clinical signs and symptoms to differentiate subclinical keratoconus from the normal is not observed. The Pentacam is based on the Scheimpflug principle. This technique can be used as a screening test for detecting KC since it works independent of axis, orientation and position of the eye. A retrospective study was conducted on patients recruited from Kobry EL Qobba outpatient clinics. The retrieved data revealed 400 eyes of 200 patients photographed during the period from January 2013 to December 2013.

Eighty seven (87) patients, (160) eyes were selected for this study to measure the prevalence of keratoconus in Egyptian astigmatic people, the selection was based on having astigmatism more than 1.5D in an age group from 20 years old to 50 years old. The Scheimflug device (pentacam) presented in Kobry El-Qobba Military Hospital was the device used for this study. The selected cases were classified according to their age to 3 groups; group A, group B and group C. The mean age of the presentation of the disease was 30±10 years old. The prevalence of keratoconus among the cases of study was (58.75%), the incidence was higher in females (56.4%) than males (41.6%). The prevalence of KC in the group A was (59.60%), in the group B was (48.10%) and in the group C was (92.90%). Most of the cases diagnosed as keratoconus had astigmatism more than (1.5D) with increasing K- readings and decreasing in pachymetery and the thinnest point of the cornea. According to this study, subjects with astigmatism more than (1.5D) or greater attending to outpatient clinics should be screened for early diagnosis even if their visual acuity is not affected. New intervention modalities are used in early diagnosis of the disease such as, CXL, ICRS to held the progression of keratoconus.