| Abstract: |
Amblyopia can be defined as a unilateral or rarely bilateral condition in which the best corrected visual acuity is poorer than 6/6, which can’t be corrected by refractive means and in absence of any obvious structural or pathological abnormality.Amblyopia posses an important socioeconomic as well as medical problem and its management constitute a challenge to the ophthalmologists. It is the most common cause of diminution of vision in children before the age of 6 years. It is most probably due to some interruption of clear normal visual stimuli which needed to reinforce the normal development of visual function during the critical period.The incidence of amblyopia is about 2-3% of population and increases in case of patients with +ve family history of strabismus and amblyopia and in premature children.Amblyopia is a preventable disease and can be detected and treated before the age of 5 years by screening program, family education ,preschool/ and primary school children screening and managing suspicious cases early.According to the aetiology, amblyopia can be classified into:- Strabismic amblyopia-Anisometropic amblyopia- Isometropic amblyopia - Deprivation amblyopiaAfter exclusion of organic ocular disease, amblyopia can be diagnosed by:1- visual acuity measurement: there is 2 lines or more difference between both eyes not corrected by refractive means.2-Crowding phenomena: the ability of the amblyopic eye to see optotype single vision is better than optotype linear vision.3-Pinhole test: visual acuity reduction due to amblyopia does not improve by pinhole.4-Neutral density filter: visual acuity reduction in case of organic disease is greater than reduction in case of amblyopia.5- Background illumination: the amblyopic eye is at its best vision in dim light than bright light.
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