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Updated: Sep 16, 2025
Inducement and Evaluation of a Murine Model of Experimental Myopia
Published on: January 22, 2019
Alterations in Peripheral Refraction are Most Significant Just Before the Onset of Myopia: Evidence from
Feijia Xie1,2,3, Xukai Mao1,2,3, Mingming Jiang1,2,3
1Eye Institute of Shandong First Medical University, Qingdao Eye Hospital of Shandong First Medical University, Qingdao, Shandong, People's Republic of China.
Insights
Retinal defocus values (RDVs) show significant changes before axial length reaches 23mm, indicating potential for myopia prediction. Temporal retinal defocus varied most, suggesting nasal visual input influences refractive outcomes in children.
Area of Science:
- Ophthalmology
- Optometry
- Pediatric Eye Care
Background:
- Refractive development in children is crucial for visual health.
- Understanding retinal defocus values (RDVs) is key to analyzing refractive errors.
- Chinese children's refractive development characteristics are under investigation.
Purpose of the Study:
- To explore the characteristics of retinal defocus values (RDVs) in Chinese children.
- To identify potential predictors for myopia occurrence based on RDVs.
- To analyze the relationship between RDVs and ocular biometric parameters.
Main Methods:
- A cross-sectional study included 2125 children aged 4-15 years.
- Ocular parameters like axial length (AL) and corneal curvature were measured.
- Multispectral refractive tomography (MRT) assessed total and regional RDVs.
Main Results:
- RDVs generally shifted towards hyperopic defocus with decreasing diopters, except for the superior retina which showed consistent myopic defocus.
- RDV-45 and temporal RDVs (RDV-T) exhibited the most significant changes.
- Hyperopic shifts in RDVs were most pronounced before 23mm AL and in the transition from emmetropia to low myopia.
Conclusions:
- Significant changes and inequalities in RDVs before 23mm AL may predict myopia onset.
- Temporal retinal defocus variations suggest nasal visual information influences refractive development.
- Early myopia is associated with peak differences between superior and inferior RDVs.
Introduction:
This study aims to explore the characteristics of retinal defocus values (RDVs) during refractive development of Chinese children.
Methods:
In this cross-sectional study, 2125 children (2125 right eyes) aged 4-15 years were included and divided into several groups according to spherical equivalent (SE) or axial length (AL). Ocular biological parameters including AL, central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT) and corneal curvature were detected, and multispectral refractive tomography (MRT) was used to measure total retinal defocus values (TRDV), RDVs of 0°-15°/15°-30°/30°-45° concentric annulus area (RDV-15/30/45), RDVs of the superior, nasal, inferior and temporal fan-shaped region (RDV-S/N/I/T).
Results:
CCT and ACD increased while LT decreased with myopia progression. As diopter descended, almost all RDVs gradually inclined to hyperopic defocus; however, the superior retina demonstrated consistent myopic defocus across different dioptric states. RDV-45 and RDV-T changed most obviously among RDV-15/30/45 and RDV-S/N/I/T, respectively. Importantly, hyperopic shift of RDVs was most pronounced between the emmetropia and low myopia group, and also when AL was approximately 23 mm. Additionally, difference between superior and inferior RDVs also peaks in early myopia.
Conclusions:
The rapid changes and longitudinal inequality of RDVs are most significant just before 23 mm of AL, this condition may have important predictive value for the occurrence of myopia. Additionally, defocus of the temporal retina showed the greatest variation in dioptric development, suggesting that nasal visual information may affect refractive outcomes.
