Background: Usage of digital devices has become one’s basic need. Digital eye strain is repeatedly noticed sequelae in optometry practice.
Objectives: This study aims to estimate the different aspects of eye strain.
Methodology: Altogether, 55 students with a mean age of 21.25 years, vision (?6/9) were enrolled. A survey related to common asthenopic (eyestrain) symptoms was carried before and after reading an extract from a novel. Accommodative facility and non-invasive first tear breakup (NTBUT) time were measured before and after the reading. The viewing distance to a smartphone was measured every 20 min.
Results: The total eye strain symptom score was significantly greater post-experiment (score = 7.07±2.84) than preexperiment (score = 1.54±1.60, p < 0.001). Symptoms of tired eyes, sore eyes, and sleepy eyes increased significantly after 60 min of a smartphone use (p < 0.05). The mean viewing distance while using a smartphone over 60 min was 30.15 ± 3.29 cm. There was a significant correlation between change in total symptom score and change in viewing distance (r = -0.301, p = 0.026). The symptom that correlated with a change in viewing distance was ‘sore eyes’ (r = -0.382, p = 0.04) and sleepy eyes (r= -0.363, p=0.06). There was a significant decrease in monocular and binocular accommodative facilities and NTBUT after 60 min of reading.
Conclusion: Closer viewing distance and eyestrain symptoms are obvious after a smartphone reading. Prolonged use of smartphones appears to have important implications for accommodative function, causing ocular symptoms having an impact on quality of life.
Uchino M, Yokoi N, Uchino Y, Dogru M, Kawashima M, et al. Prevalence of dry eye disease and its risk factors in visual display terminal users: The Osaka study. Am J Ophthalmol. 2013; 156: 759–6. [DOI]
Gavali MY, Khismatrao DS, Gavali Y V., Patil KB. Smartphone, the new learning aid amongst medical students. J Clin Diagnostic Res 2017; 11: JC05–JC08. [DOI]
Arthur C. The history of smartphones: timeline. Guard. 2012; : 24. 4. Wallace S, Clark M, White J. ‘It’s on my iPhone’: Attitudes to the use of mobile computing devices in medical education, a mixed-methods study. BMJ Open 2012; 2. [DOI]
Payne KFB, Wharrad H, Watts K. Smartphone and medical related App use among medical students and junior doctors in the United Kingdom (UK): A regional survey. BMC Med Inform Decis Mak 2012; 12: 121. [DOI]
Sayedalamin Z, Alshuaibi A, Almutairi O, Baghaffar M, Jameel T, Baig M. Utilization of smart phones related medical applications among medical students at King Abdulaziz University, Jeddah: A cross-sectional study. J Infect Public Health 2016; 9: 691–7. [DOI]
Karki S, Singh JP, Paudel G, Khatiwada S, Timilsina S. How addicted are newly admitted undergraduate medical students to smartphones?: a cross-sectional study from Chitwan medical college, Nepal. BMC Psychiatry 2020; 20. [DOI]
Brian Chou OD. Deconstructing the 20-20-20 Rule for digital eye strain. Optometry Times. 2018 Mar 1;10(3):21-3. [URL]
Long J, Cheung R, Duong S, Paynter R, Asper L. Viewing distance and eyestrain symptoms with prolonged viewing of smartphones. Clin Exp Optom 2017; 12453. [DOI]
Park M, Ahn YJ, Kim SJ, You J, Park KE, Kim SR. Changes in Accommodative Function of Young Adults in their Twenties following Smartphone Use. J Korean Ophthalmic Opt Soc 2014; 19: 253–60. [DOI]
Jaiswal S, Asper L, Long J, Lee A, Harrison K, Golebiowski B. Ocular and visual discomfort associated with smartphones, tablets and computers:what we do and do not know. Clin. Exp. Optom. 2019; 102(5): 463–77. [DOI]
Kim DJ, Lim C-Y, Gu N, Park CY. Visual Fatigue Induced by Viewing a Tablet Computer with a High-resolution Display. Korean J Ophthalmol 2017; 31: 388–93. [DOI]
Schor C, Horner D. Adaptive disorders of accommodation and vergence in binocular dysfunction. Ophthalmic Physiol Opt 1989; 9: 264–8. [DOI]
Choi JH, Li Y, Kim SH, Jin R, Kim YH, et al. The influences of smartphone use on the status of the tear film and ocular surface. PLoS One 2018; 13. [DOI]
Gowrisankaran S, Sheedy JE. Computer vision syndrome: A review. Work. 2015; 52–2: 303–14. [DOI]
Bababekova Y, Rosenfield M, Hue JE, Huang RR. Font size and viewing distance of handheld smart phones. Optom Vis Sci 2011; 88: 795–7. [DOI]
J L. The effect of character size on working distance at a computer screen. 2000: 40–5. 18. INTERNATIONAL STANDARD ORGANIZATION. Human-centred design for interactive systems (9241- 210). In: Ergonomics of humansystem interaction. 2010. 19. Ko P, Mohapatra A, Bailey IL, Sheedy J, Rempel DM. Effect of font size and glare on computer tasks in young and older adults. Optom Vis Sci 2014; 91: 682– 9. [DOI]
Nahar NK, Sheedy JE, Hayes J, Tai YC. Objective measurements of lower-level visual stress. Optom Vis Sci 2007; 84: 620–9. [DOI]
Rempel D, Willms K, Anshel J, Jaschinski W, Sheedy J. The effects of visual display distance on eye accommodation, head posture, and vision and neck symptoms. Hum Factors 2007; 45: 830–8. [DOI]
Rosenfield M, Ciuffreda KJ. Cognitive demand and transient nearwork-lnduced myopia. Optom Vis Sci 1994; 71: 381–5. [DOI]
Golebiowski B, Long J, Harrison K, Lee A, ChidiEgboka N, Asper L. Smartphone Use and Effects on Tear Film, Blinking and Binocular Vision. Curr Eye Res 2020; 45: 428–34. [DOI]
Kim J, Um JY, Sung HN, Kim SR, Park M. Changes in Accommodative Function after Reading with Paper Book and E-book on Tablet PC. J Korean Ophthalmic Opt Soc 2017; 22: 183–90.: [DOI]
Kwon K, Woo JY, Park M, Kim SR. The change of accommodative function by the direction of eye movements during computer game. J Korean Ophthalmic Opt Soc 2012; 17: 177–184. 26. Davies LN, Wolffsohn JS, Gilmartin B. Cognition, ocular accommodation, and cardiovascular function in emmetropes and late-onset myopes. Investig Ophthalmol Vis Sci 2005; 46: 1791–6. [DOI]