الفهرس Only 14 pages are availabe for public view
 |  | from | 172 |  |  |
| | | from | 172 | | |
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 amblyopia
After 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.