Relative Myopic Defocus in the Superior Retina as an Indicator of Myopia Development in Children

Abstract

Purpose To investigate the role of peripheral refraction in children's myopization. Methods This 2-year study included 214 children (8–15 years old). Refraction across the retina (field of view: 60° × 36°) was measured with a custom-made aberrometer every year. Three datasets were established: dataset 1, 214 subjects from baseline to the first-year visit; dataset 2, 152 subjects from baseline to the second-year visit; and dataset 3, 59 initial emmetropes from baseline to the second-year visit. The baseline refraction of different retina regions was correlated with the central myopic shift, and was compared among groups with different levels of myopic shift. Results In datasets 1 and 2, the refraction distribution across the retina was significantly different among the subjects who were initially emmetropes but not among those who were initially hyperopic or myopic. Refraction in the central vertical retina, especially in the superior retina ( r = −0.5, P < 0.001), was significantly correlated with the myopic shift for emmetropes in that subjects with more relative myopia in the superior retina manifested greater central myopic shifts. In dataset 3, 21 subjects remained emmetropic after 2 years, 15 subjects became myopic at the 1-year visit, and 23 subjects became myopic at the 2-year visit. No difference was found for the relative peripheral refraction in all of the peripheral regions between the stage prior to and after the onset of myopia. Conclusions Relative myopic defocus in the superior retina could be a predictor of central myopia shift. Changes in relative peripheral refraction are more likely a consequence of myopia progression rather than a cause.

The association of peripheral refraction and relative peripheral refraction with astigmatism in Shanghai schoolchildren’s myopia: a cross-sectional study

“…As age and axial length increased, the spherical equivalent decreased, and peripheral relative hyperopia increased, suggesting that relative peripheral hyperopia remains an important risk factor for axial elongation and myopia development in children with low-to-moderate myopia. Saunders 30 and Lan 31 conducted longitudinal studies and found that peripheral relative refraction was indicative of an increased risk for axial elongation and central myopia. However, as this was a cross-sectional study, it is not su cient to indicate that peripheral relative hyperopia accelerates myopia development 19,32,33 .…”

The induced defocus by Defocus Incorporated Soft Contact lenses is dependent on visual distance and ambient illuminance

“…Spherical equivalent refractive error (SER), astigmatism and higher order aberrations (HOA) were obtained for each retinal location (61 points in the horizontal meridian), 11,[20][21][22] and experimental condition. Pupil diameter was measured from three random Hartmann-Shack images using the VPR at each trial (61 images) and condition.…”

“…The sensor was able to provide a resolution of 1° in the visual field, as noted previously. 11,[20][21][22]…”

“…11,[20][21][22] The target was placed directly Profile of a Defocus Incorporated Soft Contact lens having a diameter of 14.20 mm. Around the central correction zone (white) of 3 mm diameter, there are five defocusing rings (grey), each having a width of 0.25 mm.…”

Adaptive Illuminance Effects on Retinal Morphology and Refraction: A Comprehensive Study of Night Myopia

“…It is conceivable that myopia could start developing at the superior retina, gradually extending to the posterior eyeball, largely influenced by genetic factors. Notably, when emmetropic individuals transitioned to myopia, their ocular shape tended to change more in terms of height than width; these findings shed light on the complex interplay of factors in myopia development, particularly in the superior retina [ 30 ]. In our current study, the superior thickness was not the area most influenced by the lighting conditions evaluated, and the results revealed significant differences in eccentricity in both photopic and scotopic conditions when comparing the central and peripheral retina, leading to a reduced peripheral retinal curvature at the analyzed horizontal plane.…”