Abstract
Purpose :
Hyperopia results from insufficient axial growth and failure to emmetropise in childhood usually resulting from an eye that is too short for its refractive power. The purpose of the present study was to determine if imposed relative hyperopic defocus using multifocal contact lenses could accelerate axial growth in children with hyperopia.
Methods :
Participants with hyperopia aged between 8 and 15 years inclusive were recruited. Maximum manifest spherical refractive error was +6.00D, minimum manifest spherical refractive error in the more hyperopic eye was +2.00D, and maximum cylindrical refractive error was -1.00D.
There were 3 arms to the study:
The natural progression arm (control) followed axial growth in hyperopes (n=12) for 18 months.
The second arm followed axial growth in hyperopes (n=11) for 6 months. After this period, participants wore centre-near multifocal soft contact lenses in both eyes to impose relative peripheral hyperopic defocus, for 12 months.
The third arm followed axial growth in anisohyperopes (n=11) for 6 months. After this period, participants wore a centre-near multifocal soft contact lens in their more hyperopic eye to impose relative peripheral hyperopic defocus, and a single vision contact lens in the fellow eye, for 12 months.
Axial growth was measured using a Zeiss IOLMaster 500 at 6-monthly intervals in all 3 arms of the study.
Results :
Axial growth in the natural progression arm was unchanged at the 6- (0.02mm; p=0.210), 12- (0.02mm; p=0.105), and 18-month intervals (0.01mm; p=1.000). Axial growth for hyperopes in the second arm was unchanged at 6 months (0.01mm; p=1.000) but accelerated after intervention by the 12- (0.05mm; p=0.001), and 18-month time points (0.04mm; p=0.002). In the third arm, axial growth in the anisohyperopes’ more hyperopic eye was unchanged at the 6- (0.03mm; p=0.700), and 12-month intervals (0.04mm; p=0.067) but accelerated between the 12- and 18-month time points (0.03mm; p=0.007). For the anisohyperopes’ fellow eye, axial growth changed at 6 months (0.08mm; p=0.001), was unchanged at 12 months (0.03mm; p=0.275) but changed between the 12- and 18-month time points (0.05mm; p<0.001).
Conclusions :
The results are consistent with our hypothesis that imposing relative peripheral hyperopic defocus can accelerate axial growth in hyperopes, which could have far-reaching implications for the visual outcome in this cohort.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.