Peripheral refraction under different levels of illuminance

Peripheral refraction is believed to be involved in the development of myopia. The aim of this study was to compare the relative peripheral refraction (RPR) at four different levels of illuminance, ranging from photopic conditions to complete darkness, using an open-field autorefraction method. The RPR was calculated for each eccentricity by subtracting central from peripheral autorefraction measurements. The study included 114 myopic eyes from 114 subjects (mean age of 21.81 +/- 1.91 years) and the mean difference in RPR between scotopic and photopic conditions (0 and 300 lux, respectively) was +0.32 D at 30 degrees temporal and +0.37 D at 30 degrees in the nasal visual field (NVF). Statistically significant differences were observed between 0 and 300 lux at 30 degrees in the temporal visual field and at 30 degrees and 20 degrees in the NVF. Our results revealed a significant increase in relative peripheral hyperopia with increasing visual field eccentricity along the horizontal visual field in myopic eyes of young adults. Furthermore, this relative peripheral hyperopia increased as illumination decreased. These findings suggest that an increase in peripheral illuminance may protect against myopic eye growth.

Automated summary

This study compared relative peripheral refraction (RPR) under different levels of illuminance and found a significant increase in relative peripheral hyperopia in myopic eyes under dark conditions. Increasing peripheral illuminance may protect against the development of myopia.