Evaluation of Intraocular Pressure Changes after Smartphone Usage under Bright Light and Dim Light in Healthy Individuals

Abstract

Introduction: Excessive smartphone use is associated with various eye-related issues commonly referred to as Computer Vision Syndrome (CVS. The proposed mechanism for CVS is a sustained effort for accommodation and the accompanying ocular-surface-related changes such as dry eye while using electronic devices. Intraocular pressure (IOP) also shows temporary but significant fluctuations while using these devices.

Methodology: The study was approved by the institutional research and ethics committee. All emmetropic patients attending OPD at the ophthalmology department of tertiary care hospital, aged more than 18 years and ≤ 50 years were included in the study after taking written and informed consent. The participants were requested to conduct standardized work with a smartphone (i.e., either reading or watching videos) under bright light [1100-1300 LUX] and dim light [350-477 LUX] conditions. On each light setting, 5 sets of intraocular pressure(IOP) measurements were taken using a non-contact tonometer: (1) pre-work (baseline) (2) during smartphone work [5, 15, and 25 minutes], and (3) post-work [5 and 15 minutes].

Results: Under bright and dim light conditions, in both eyes the mean baseline IOP increased after the 25 minutes of smartphone work. In both bright light and dim light conditions, IOP returned to the baseline in both eyes at post-work 15 minutes, more rise in IOP was noted in dim light conditions. A greater number of younger individuals showed a rise in IOP when compared to the elderly. More females had raised IOP when compared to males.

Conclusions: In conclusion, using a smartphone while working can temporarily raise IOP in bright and dim light. In addition, there was more rise in IOP in the dim light.  Smartphone users are advised to take a break if they use their device for reading or texting for longer than ten minutes. Further, they can avoid using their device in dim light areas whenever possible.