Visual acuity outcome in isometropic hyperopia.

Refractive amblyopia may occur as a unilateral or bilateral condition. Although bilateral refractive amblyopia may account for 1 to 2% of all refractive amblyopia, there is little consistent information in the literature regarding isoametropic amblyopia resulting from bilateral hyperopia. Hence, this retrospective study investigated the prevalence of reduced aided acuity in patients aged 10 years and younger (mean age 3.97 years) with 5 D or more of isometropic hyperopia and considered the following factors that may influence visual acuity: (1) age at first correction; (2) magnitude of hyperopia; and (3) duration of refractive correction of the hyperopia. The results indicate that the majority of patients (87%) have aided acuity poorer than 6/6 at initial correction of refractive error. However, if the full hyperopic correction was worn for 1 year or longer, only 43% of these patients demonstrated acuity poorer than 6/6 and none showed acuity poorer than 6/12. The magnitude of the hyperopia appeared to have the greatest influence on the visual acuity outcome both at initial correction of refractive error and 1 year or longer after correction. Duration of correction also influenced the visual acuity outcome, but to a lesser extent than the magnitude of refractive error. In contrast, the age of first correction showed little correlation with visual acuity either at the time of first refractive correction or after a minimum of 1 year of correction.