Abstract
Purpose
The present study aimed to investigate the change of accommodative function of vergence anomalies subjects in their 20s after near work with smartphone.
Methods
Adults in their twenties (131 subjects, mean age 22.1±3.3 years) with a corrected and uncorrected visual acuity of 0.8 or better were examined and classified into normal, convergence insufficiency (CI), and convergence excess (CE) according to the function of convergence. The accommodative facility, relative accommodation, and accommodative lag were measured after watching the smartphone for 30 minutes.
Results
Monocular accommodative facility was significantly decreased in normal and CI group, and binocular accommodation facility was significantly decreased only normal group. Negative relative accommodation (NRA) decreased in 53.8% of CI group, which was different from 36.0% of normal group. In normal group of 48.0%, there was an increase in positive relative accommodation (PRA), but in CE group only 20.0% was increased. However, in CE group, the increase in PRA was greater than 1.50 D. The accommodative lag increased in 80.0% of CE group and was larger than that of the normal group(48.0%).
Conclusions
this study found that the accommodative function after near work with smartphone varies depending on the vergence function of the subject. The difference in the accommodative function induced by the variation of the vergence function may be the cause of the individual subjective symptom difference after using the smartphone.
The present study aimed to investigate the change of accommodative function of vergence anomalies subjects in their 20s after near work with smartphone.
Methods
Adults in their twenties (131 subjects, mean age 22.1±3.3 years) with a corrected and uncorrected visual acuity of 0.8 or better were examined and classified into normal, convergence insufficiency (CI), and convergence excess (CE) according to the function of convergence. The accommodative facility, relative accommodation, and accommodative lag were measured after watching the smartphone for 30 minutes.
Results
Monocular accommodative facility was significantly decreased in normal and CI group, and binocular accommodation facility was significantly decreased only normal group. Negative relative accommodation (NRA) decreased in 53.8% of CI group, which was different from 36.0% of normal group. In normal group of 48.0%, there was an increase in positive relative accommodation (PRA), but in CE group only 20.0% was increased. However, in CE group, the increase in PRA was greater than 1.50 D. The accommodative lag increased in 80.0% of CE group and was larger than that of the normal group(48.0%).
Conclusions
this study found that the accommodative function after near work with smartphone varies depending on the vergence function of the subject. The difference in the accommodative function induced by the variation of the vergence function may be the cause of the individual subjective symptom difference after using the smartphone.
| Translated title of the contribution | The Change of Accommodative Function of Vergence Anomalies Subjects in their Twenties after Near Work with Smartphone |
|---|---|
| Original language | Korean |
| Pages (from-to) | 71-80 |
| Number of pages | 10 |
| Journal | 한국안광학회지 |
| Volume | 22 |
| Issue number | 1 |
| DOIs | |
| State | Published - Mar 2017 |