Abstract
Purpose :
we have previously introduced a novel device ClouclipTM to record dynamically viewing distance and eye-received illuminance, the two known environmental risk factors (ERF) of myopia (2016 ARVO abstract: IOVS, 2016, Vol.57, 2491), and identified the correlation between these factors and refractive error (2017 ARVO abstract: 2017, Vol.58, 2403). Here we introduce an index to summarize whether or not one’s overall ERF is myopicgenic in a quantitative fashion (a negative value indicates myopicgenic and a positive value indicates hyperopicgenic; this part is submitted as another abstract this year) and investigate the correlation between the ERF index and the change of refractive error over time.
Methods :
The ERF of subjects were measured via ClouclipTM for a period of a week with 6 months apart, along with the measurement of refractive error via cycloplegic autorefraction. The change of individual ERF index over time was compared by paired-t test, and correlated with individual baseline as well as the change of refractive error, respectively, by Person’ correlation analysis.
Results :
Ninety Grade 4 subjects (Age: 10-12y, Mean +/- SD of SER: 0.20+/- 1.08D) completed the 6-month measurement of ERF, the index was found decreased significantly (t=7.23, p<0.001), indicating myopicgenic behavior occurred during these period. No correlation was found between individual baseline refractive error and the change of ERF index (r=0.03, P=0.33). Nevertheless, significant positive correlation was found between the change of the ERF index and the refractive change (r=0.04, P=0.02) for the 14 subjects (baseline SER: -0.20 +/- 1.05D; refractive change: -0.27 +/- 0.25D) who have completed the 6-month refractive measurement until now.
Conclusions :
The results provide objective evidence to support environmental role in myopia development. More convincing date will be obtained in the further follow-up study.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.