Prevalence of amblyopia in primary school children at central Cairo

Abstract

Amblyopia is considered the commonest cause of visual impairment in childhood and adulthood. This study revealed that prevalence of amblyopia was 1.98% among school children aged from 8-12 years old. Amblyopia screening using available, non-expensive, easy to be learned to trainee test (snellen’s chart VA test) is the gold standard method in amblyopia screening. Sensitivity at low cut off value (0.539 logMAR) was 100% at specificity 96% in detection of proved amblyopia and 65% in detection of suspected amblyopia. At high cut off value (0.238 logMAR), sensitivity was also 100%, but with specificity 89% in detection of proved amblyopia and 5% in detection of suspected amblyopia. Whereas amblyopia has multiple hazardous effects on developmental, educational, occupation, psychological aspects, vision loss of both amblyopic and sound eye, prehension and motor skills deficits along short and long term life of amblyopic patients, early screening has a role in prevention of these hazardous effects.

Conclusion: Timely diagnosis and treatment is likely to reduce the prevalence of amblyopia as has been seen in many countries that have taken up mass education and visual screening as important community aids to increase knowledge and awareness about the condition. The high prevalence rates indicate the need of earlier screening and treatment of predisposing factors of amblyopia at younger age. Hyperopic refractive error represents the main risk factor among amblyopia cases. Distant visual acuity test using snellen’s chart is an ideal method for amblyopia screening. As the prevalence of amblyopia decreases, the educational, psychological, motor function and occupational skills increase.

Recommendation: • Systematic screening in all pediatric age groups starting from infancy to preschool and school age children, as early amblyopia screening may alter the prognosis and treatment efficacy.

• In the setting of community and school-based screening programs, screeners should have specific training in vision screening techniques and protocols. Children who do not pass these screenings should be referred for an additional ocular assessment performed by the primary care provider or an eye care provider with training and experience in treating children.

• Since VA of children is still under development naturally, different VA cutoffs should be adopted for different age groups.

• Contact with governmental hospital to refer the suspected cases for completion of comprehensive examination.

• Screening for amblyopia as soon as a child can undertake a visual