Association of smartphones use, ocular symptoms and binocular dysfunctions in adolescents: a hospital-based cross-sectional study.

Purpose: Given the current scenario of increased smartphone use in youth, this study aims to evaluate the proportion of ocular symptoms and binocular dysfunction and their association with smartphone use in adolescents through a hospital-based cross-sectional study.

Methods: The participants were asked to fill out questionnaires related to smartphone use and symptoms of eyestrain experienced (Balik et al. and Kucer). They were asked about the following seven symptoms: blurring of vision, redness, visual disturbance, secretion, inflammation, lacrimation, and dryness. Each symptom out of the 7, was scored on a scale of 0-1 and was used to calculate an Ocular Symptom Score (OSS) by summing the scores of each symptom.Depending upon the duration of smartphone usage, the participants were classified into four groups: <2 hours/day, 2-4 hours/day, 4-6 hours/day, and >6 hours/day. Binocular functions were assessed using near point of convergence (NPC), near point of accommodation (NPA), Accommodative convergence/Accommodation (AC/A) ratio, dissociated heterophoria, and binocular accommodative facility (BAF).

Results: A total of 123 smartphone user adolescents, aged 10-19 years were included in this study. The mean age of the study population was 16.58 + 2.8 years, out of which 52.03% were males. Prevalence of ocular symptoms was higher in groups with greater duration of smartphone use (2 to 4, 4 to 6, and >6 hours/day as compared to <2 hours/day: 90.48%, 94.74%, 100% vs. 75% respectively). The mean of NPC was 8.51, it was highest in subjects using smartphones for >6 hours. (-value = .001). The mean AC/A ratio was 2.83 + 1.03: 1. A low AC/A ratio was associated with a longer duration of smartphone usage (-value = .0001). The mean of BAF was 7.4 + 3.18 cycles/min, only 30 (24.4%) participants had BAF beyond the normal range (<5 cycles/min). The mean of BAF was lowest in the group with >6 hours/day of smartphone use (-value < .0001). No significant change was found in NPA and dissociated heterophoria with the duration of smartphone usage.

Conclusion: Higher duration of smartphone use (>2 hours/day) is associated with various ocular symptoms and binocular dysfunction. However, additional research is necessary to authenticate the results of the study.