Long-term Observations on the Emmetropization of the High Hyperopia

Purpose : We are to investigate the reduction rate of high hyperopia, that is, process of emmetropization. Methods : Thirty children who had hyperopia more than spherical equivalent of +4.0 diopter and could be followed at least 3 years were reviewed retrospectively. Data including visual acuity and the magnitude of hyperopia were collected every 6 months from 3 years of age. Annual reduction rates of hyperopia were analysed. Changes in the level of hyperopia were compared with those who had strabismus or astigmatism and those who did not. Results : The children who had higher degree of initial hyperopia showed the faster rates of annual reduction but also significantly higher level of remained hyperopia (p=0.003). The concurrent presence of astigmatism was associated with a lesser reduction in hyperopia (p=0.01). Conclusions : Our data show that, as a whole, the emmetropization of high hyperopia occurs as a linear function of the initial level and converges toward a low hyperopic value. We have also found that astigmatism might impede emmetropization.