Abstract
Purpose :
The optical quality in the near periphery has been associated with refractive error development. We investigated for the first time longitudinal changes in peripheral optical quality in children at High (HR) or Low Risk (LR) for myopia, including children who developed myopia during the study time.
Methods :
Young children with functional emmetropia (n=92, 7.46±0.96yrs, SE OD +1.01±0.55D, and AXL OD 22.76±0.64mm at enrollment) participating in the PICNIC study (those with a minimum of 3 visits over 3 years) were included in these analyses. Subjects were divided into HR and LR, based on parental myopia and baseline SE. Optical quality across the central horizontal ±30° was assessed using a scanning aberrometer while children looked at 6m (Dist) or 40cm (Near). Strehl ratios, Defocus (Z4) and primary Spherical Aberration (SA, Z12) were computed for 4mm diameter pupils. Aberration curves were transformed with a Savitzky-Golay filter and AUC calculated for each; parametric tests were used to assess changes over time and differences between risk groups.
Results :
Children at HR for myopia have overall larger peripheral Dist Strehl ratios than those at LR (F=3.901, P<0.001) that decrease over time (Z=-1.96, P=0.049). A trend for less positive Dist Z12 was noted across the periphery in children at HR (Z=-1.698, P=0.058), with similar effect across all eccentricities, but not on-axis. Near Z12 were also less positive in children at HR, although only in the initial visits (M0 – M12). No significant changes over time were noted for Dist Z12, with a trend for less positive Near SA with time. Peripheral Dist Z4 were larger in children at HR (F=4.010, P=0.001) and increased over time in all children (Z=2.34, P=0.009), uniformly in children at LR and with a non-uniform pattern in children at HR (only increased between 4 - 16 degrees temporal retina). Near Z4 were also larger in children at HR, but decreased over time to reach no difference with children at LR by M24. The results in the subgroup of children who have so far developed myopia confirm the findings in children classified as having HR for myopia.
Conclusions :
Differences in near-peripheral optical quality between children at high or low risk for myopia are present years before children develop myopia, with different patterns of differences for Strehl ratios, Defocus and SA. These early differences in the eye optics may have implications in myopia development.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.