The main purpose of this research was to determine the eye anomalies in People with down syndrome in iran, regarding its high global prevalence., the study encompasses the incidence of refractive errors,Strabismus, Nystagmus ,Keratoconous,Cataract and Blepharitis also the comparison of average V.A and refractive errors in genders and optical glass wearers or non wearers.

A Total of 82 people with Down syndrome in Institute for Down Syndrome people in Karaj-Iran ( mean age 17.70 ±7.656 ) underwent Eye examinations in order to detect eye anomalies and to determine the average VA as well. and the appropriate procedures towards the results were conducted respectively .The SPSS 20 software , T-Test ,Chi-Squared and pearson colleration were used to analyze as required.

Overall prevalence of eye anomalies(Hyperopia,Myopia,Astigmatism,Strabismus,Keratoconous,Blepahritis,Nystagmus and Cataract) in people with D.S are:54.3%,28.6%,81.3%,36.6%,%,6.1,%65.9, 11% and 31.7% respectively. Prevalence of Astigmatism types including With the rule, oblique and against the rule were 52.4%,23.2% and 6.1% in order of decreasing. Esotropia was recognized as the most common type of strabismus. The average VA in subjects with or without Anisometropia shows a significant difference.(P=0.001). The average VA in subjects with or without optical correction were 27.55±0.03710 and 0.4417±0.03524 respectively. The average of Mypoia &Hyperopia in subjects with or without correction showed no significant difference.

Iranian people with D.S demonstrated high incidents of refractive errors especially Hyperopia , Astigmatism also blepharitis , Strabismus and cataract respectively, which indicates the high importance of routine eye examination in these population which would improve the quality of life of them either. in this way the correction of other prevalent refractive anomalies like anisometropia and oblique astigmatism is necessary in the early childhood. Mainly the high prevalence of refractive errors and its high correlation with visual acuity reveals the highest priority of optical corrections in this population.