بررسي شيوع انواع و مقدار عيوب انكاري چشم در سنين مختلف در بيماران معاينه شده در كلنيك ويژه بينايي سنجي دانشگاه علوم پزشكي مشهد

A study of the prevalence of types and amounts of refractive errors in different ages amongpatients examined at the department of optometry,Mashhad University of Medical Sciences

A cross sectional study of refractive errors from a clinical sample of 2410 patients (4820 eyes) from the Optometry Department, Mashhad University of Medical Sciences was performed ranging from 1 to 97 years of age by using the SPSS software computer.The purpose of this research was to investigate the prevalence of types and amounts of refractive errors in different ages in steps of 5 years. The results of this investigation showed that prevalence and amount of myopia increase with increasing of age until 20 years and vice versa, hyperopia decreases. These changes are not significant until 40 years, and then by beginning of presbyopia, the prevalence and amount of myopia decrease and vice versa, hyperopia increases. It is interesting to note that the prevalence of with-the-rule astigmatism was more than the prevalence of against-the-rule one after presbyopia. Significant changes were found in the amount of astigmatism with advancing years.