Ophthalmic changes from age of 10 to 18 years. A longitudinal study of sequels to low birth weight. I. Refraction.

A report is given on refractive changes (delta R) from age of 10 to 18 years. The 1979 follow-up comprises 137 persons who had earlier (around 1970) participated in a larger investigation into ophthalmic sequels to a low birth weight (n = 539). In general (127 out of 137), there is a shift towards lower dioptric values (increase in refraction). Seven remained static while three showed a slight decrease in refraction (0.25-0.5 D). Adult emme- and hypermetropia show a median delta R about 0.7 D (increase) during adolescence, against median values of 1.7 and 2.5 D in juvenile myopia, of ex-prematures and full-terms respectively. With a median delta R of 1.2 D, 'myopia of prematurity' occupies an intermediate position (21 eyes of 13 subjects). Except for this subgroups, there is no evidence that low birth weight has influenced refractive distribution. With a (planned) skewing towards myopia, the 1979-sample cannot be considered epidemiologically representative, as was the original 1970-material. Concerning the latter, the 18-year incidence of myopia is given as 17.6% for ex-prematures and 13.1% for fullterms (minimum figures, based on school medical records).