title: Astigmatism and school myopia.
abstract: Changes in astigmatism were followed for a 3-year period among 238 myopic children as part of a clinical trial of myopia treatment. Children with mild myopia and no previous myopic spectacle correction and astigmatism less than or equal to 2 D were included in the study. The prevalence of astigmatism of at least 0.25 D was 55% at the beginning of the follow-up at a mean age of 10.9 years, increasing to 76% during the 3-year period. At the same time the mean astigmatism increased from -0.26 D to -0.45 D. Most of the astigmatism was against the rule; with the rule astigmatism represented 18% of the astigmatism at the beginning and 24% at the end of the study. There was a weak correlation between the spherical equivalent and astigmatism at the beginning of the follow-up (r = 0.122, n = 240, P = 0.029) but not at the end of the follow-up. Myopic progression controlled for the spherical equivalent, was not related to degree of astigmatism at the beginning of the study.
authors.affiliation: Department of Ophthalmology, Central Hospital of Central Finland, Jyväskylä.
authors.forename: O
authors.initials: O
authors.lastname: Pärssinen
mesh_terms: D001251:Astigmatism / Q000453:epidemiology*; D002648:Child; D005139:Eyeglasses; D005260:Female; D005387:Finland / Q000453:epidemiology; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009216:Myopia / Q000453:epidemiology* / Q000628:therapy; D015995:Prevalence; D012574:Schools