Selcan EKİCİER ACAR, Zennure ÖZDEMİR YILDIZ
Gulhane Medical Journal - 2026;68(2):87-93
Aims: The use of handheld devices has increased rapidly over the past decade. Smartphones and tablets are commonly used for reading and work-related tasks. This study aims to compare the effects of smartphone and tablet screen sizes on the ocular surface of adolescents and young adults. Methods: This was a prospective observational study involving 90 healthy volunteers divided into three age-based groups: adolescents (n=30, 10-18 years), young adults (n=30, 18-24 years), and adults (n=30, 24-40 years, control). Participants read for 30 minutes using a smartphone, a tablet, and a printed book. The Ocular Surface Disease Index(C), the ocular discomfort questionnaire, fluorescein break-up time (FBUT), corneal fluorescein staining, the Schirmer test, and the blink rate were assessed before and after each reading session. Results: Ninety participants (mean age for adolescents: 13.33+/-1.33 years; young adults: 20.77+/-2.32 years; adults: 33.47+/-5.38 years; sex distribution: 56%, 56%, 53% female, respectively) were included. FBUT values decreased significantly after reading in all groups (p<0.01). In adolescents, corneal fluorescein staining significantly increased after smartphone reading, from 0 to 0.30+/-0.46 (p=0.001). Schirmer test values did not change significantly (p>0.05) among all groups. Blink rate decreased from 18.2+/-2.7 to 9.8+/-1.8 blinks/min and incomplete blinking increased from 1.8+/-0.9 to 4.9+/-1.6 blinks/min during smartphone reading (p<0.001). Discomfort scores were highest after smartphone use (34.8+/-13.8) compared with tablet (24.8+/-10.1) and print reading (21.0+/-12.4) (p<0.001). Conclusions: Reading from smartphones and tablets causes measurable alterations in ocular surface integrity, tear film stability, and blinking patterns. Ocular discomfort scores were highest after smartphone use, particularly in adolescents and young adults.These findings highlight the ocular strain associated with handheld devices and the need for preventive strategies, especially for younger populations with extended screen exposure.
