Background Hyperopic anisometropic amblyopia is considered to have worse prognosis in stereoacuity especially when the treatment is begun at late childhood. The present study investigated both near and distance stereoacuity in hyperopic anisometropic amblyopia patients who began treatment after 6 years of age and had good visual acuity in the amblyopic eye.
Methods Ten hyperopic anisometropic amblyopia patients who began their treatment after 6 years of age and improved the visual acuity of their amblyopic eye to over 0.9 were included. The age at which a patient started wearing spectacles corresponded to the age of treatment onset, whereas the number of months required to reach the best corrected visual acuity was considered as the period of treatment. Near and distance stereoacuity were measured. We performed correlational analyses between stereoacuity scores and several other variables, such as the age at which stereoacuity was measured, the binocular refractions differences, the age of treatment onset, and the period of treatment.
Results The age of treatment onset ranged from 6 to 8 years. With the exception of two patients, all subjects obtained near stereoacuity better than 100 sec and distance stereoacuity better than 120 sec following treatment. Stereoacuity scores did not significantly correlate with the age of treatment onset or with the binocular refraction differences. Stereoacuity scores (both near and distance) significantly positively correlated with the period of treatment.
Conclusion The stereoacuity of our patients reached normal levels following treatment. These findings suggested that anisometropic amblyopia should be treated aggressively even in patients older than 6 years of age.