SMARTPHONE USE AND INTRAOCULAR PRESSURE

 

Smartphone and digital device use has become very common. It would be interesting to know the effect of using phones on intraocular pressure (IOP). A few studies have been performed to analyze the effect of using smartphones on IOP.

A study was performed by Srivastava et al, to compare the effect on IOP while reading smartphone digital text and printed text in healthy, and in glaucoma patients. The study included 60 healthy and 22 patients who had medically controlled POAG. The participants were asked to perform reading tasks on printed text followed by digital text on a smartphone. The IOP assessment was done at baseline and subsequently at 10, 20, and 30 minutes of reading and 10 and 20 minutes after completing the reading tasks. IOP variations from baseline were measured and compared. The mean baseline IOP in volunteers was 14.58 (±2.91) mmHg, while in POAG patients it was 15.02 (±2.18) mmHg. The IOP was found to rise in all participants (healthy, as well as, glaucoma patients) while reading both printed text and digital text. It returned to normal 20 minutes after stopping the reading. However, there was a relatively marked rise in IOP on reading smartphone text, compared to digital text.

Ha et al, performed a study on healthy volunteers to investigate the effect of reading or writing on a smartphone on IOP changes. The study included 39 healthy volunteers less than 40 years of age. The participants were tasked to conduct standardized work (i.e., read a sample text on a single mobile device and subsequently type it on the same device) under daylight [300 lux] and low-light [100 lux] conditions independently on consecutive days. On each day, three sets of IOP measurements (total: 7) were performed: (1) pre-work (baseline), (2) during smartphone work [5, 15, and 25 minutes], and (3) post-work [5 and 15 minutes].

The study reported that the mean IOP had a persistent rise from baseline under daylight conditions. While the baseline IOP was around 14 mmHg, it increased to around 15 mmHg after 5 minutes of work, then almost 16 mmHg after 15 minutes of work, and persisted over 25 minutes of smartphone use. When the smartphone use was stopped for 5 minutes, the IOP returned to levels even below baseline levels.

The underlying ocular dynamics for these IOP changes during and after smartphone work are unclear, though the following mechanisms are assumed to be involved: 1) Accommodation and convergence; 2) external ocular muscle (EOM) contraction; 3) psychophysiological stress; 4) dry eye; 5) neck-flexion posture.

Therefore, smartphone users concerned about IOP fluctuation are advised to:

1.  Take a break if they read or write on their smartphone for more than 5 minutes, 
2.  Avoid using smartphones wherever possible in dark places.

REFERENCES:

Srivastava, Rajat Mohan; Agrawal, Siddharth; Amrin, Nayani; Bharti, Devanand. Intraocular Pressure Changes While Reading Smartphone Digital Text Versus Printed Text in Healthy Individuals and those with Glaucoma. Journal of Glaucoma 33(3):p 189-194, March 2024. | DOI: 10.1097/IJG.0000000000002314

Ha A, Kim YK, Park YJ, Jeoung JW, Park KH (2018) Intraocular pressure change during reading or writing on smartphone. PLoS ONE 13 (10): e0206061.