The Effect of Peripheral Defocus on Axial Growth and Modulation of Refractive Error in Hyperopes

Abstract

Despite the known visual and pathological implications of hyperopia, there has been inertia to address the modulation of refractive error in these individuals. Imposing relative peripheral hyperopic defocus using centre-near multifocal contact lenses accelerates axial growth in isohyperopic children. Axial growth and refractive error did not change during the 6 months prior to intervention in the intervention or control group. Axial growth across the 2-year period of intervention was 0.17 mm in the intervention group versus 0.06 mm in the control group. Refractive error change across the same period was -0.26 D in the intervention group and +0.01 D in the control group. Axial growth and refractive error during the final 6 months without intervention did not change in either group. The overall difference in axial growth between groups was significant whereas the change in refractive error was not. Imposing relative peripheral hyperopic defocus using centre-near multifocal contact lenses does not accelerate axial growth nor reduce refractive error in anisohyperopic children. In this paired eye study, axial growth and refractive error did not change during the 6 months prior to intervention in either eye. Axial growth across the 2-year period of intervention was 0.11 mm in the intervention eye versus 0.15 mm in the control eye. Refractive error change across the same period was -0.23 D in the intervention eye and -0.27 D in the fellow eye. Axial growth and refractive error during the final 6 months without intervention did not change in either group. The overall change in axial growth was greater in the control eye than the intervention eye, whereas the reduction in refractive error was comparable. Axial length measures are comparable and repeatable under pre- and post-cycloplegic conditions. Refractive error measures are comparable and repeatable at discrete time intervals after the instillation of a cycloplegic agent.