Effect of Violet Light-Transmitting Eyeglasses on Axial Elongation in Myopic Children: A Randomized Controlled Trial

Kiwako Mori,Michiko Hara,Kazuo Tsubota,Erisa Yotsukura,Yutaka Hara,Toshihide Kurihara,Akiko Hanyuda,Hidemasa Torii,Kazuno Negishi

doi:10.3390/jcm10225462

Kiwako Mori, Michiko Hara + Show 7 more

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https://doi.org/10.3390/jcm10225462

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Abstract

The fact that outdoor light environment is an important suppressive factor against myopia led us to invent violet light-transmitting eyeglasses (VL glasses) which can transmit violet light (VL), 360–400 nm in wavelength, for the suppression of myopia, and can meanwhile block harmful ultraviolet waves from sunlight. The current study is a double-blinded randomized clinical trial to investigate the myopia-suppressive effect of VL glasses compared to conventional eyeglasses (placebo glasses) that do not transmit VL. The subjects were children aged from 6 to 12 years old, the population in which myopia progression is generally accelerated, and the myopia suppressive effect was followed up for two years in a city in Japan. Periodical ophthalmic examinations, interviews, and measurements of reflection and axial length under mydriasis were performed at the initial visit (the baseline) and at 1, 6, 12, 18, and 24 months. The mean change in axial length in the VL glasses group was significantly smaller than in the placebo glasses group when time for near-work was less than 180 min and when the subjects were limited to those who had never used eyeglasses before this trial (p < 0.01); however, this change was not significant without subgrouping. The suppressive rate for axial elongation in the VL glasses group was 21.4% for two years.

Highlights

Myopia is reported to progress due to both genetic and environmental factors [1], but its precise mechanism remains unclear
It is reported that one diopter suppression of myopia reduces 20% of the possibility of blindness caused by high myopia [6,7]
The violet light (VL) glasses, which transmit VL and block detrimental constituent such as UV, were invented in our laboratory and were expected to exert potency in clinical situations. This 2-year randomized controlled study was designed to investigate the effectiveness of VL glasses in suppressing the progression of myopia, and it revealed that the mean change in axial length in the VL glasses group was significantly smaller than that in the placebo glasses group when time for near-work was less than 180 min and when the subjects were limited to those who had never used eyeglasses before this trial (p < 0.01)

Summary

Introduction

Myopia is reported to progress due to both genetic and environmental factors [1], but its precise mechanism remains unclear. When myopia progresses and turns into high myopia, the axial length grows and the shape of the eye changes, which may lead to blindness because of sequelae such as myopic maculopathy, glaucoma, and retinal detachment [3,4]. In a domestic epidemiological study, the Tajimi study, it was shown that high myopia accounted for 20% of all myopia cases and ranked first as the cause of WHO-defined blindness [5]. It is reported that one diopter suppression of myopia reduces 20% of the possibility of blindness caused by high myopia [6,7]. Early intervention to prevent myopia progression is highly significant, as it can considerably reduce the risk of sequelae of high myopia, which may lead to blindness

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