Convergence Insufficiency and Its Associated Symptoms While Reading Text from Digital Screen and Hard Copy

Doi: 10.36351/pjo.v41i4.2153

Abstract

Purpose:  To determine the asthenopic symptoms in patients reading text from digital devices versus hard copy.

Study Design:  Cross sectional, observational study.

Pace and Duration of Study:  The University of Faisalabad from August 2021 to August 2022.

Methods:  Forty subjects of 20-30 years of age were included. After proper history of patient, visual acuity was checked using LogMAR chart. The patients were asked to read from digital screen for 20 minutes and convergence was recorded using RAF ruler, 10 minutes break was given and then patients were asked to read from hard copy for 20 minutes and convergence was checked. Asthenopic symptoms were assessed using self-designed questionnaire. Number of blinks per minute were also recorded for reading from digital screen and hard copy. Data was analyzed by using SPSS version 20.

Results:  Mean convergence with reading from hard copy was 11.85±3.690 and from soft copy was 14.33±3.925(p = 0.005). Readers from digital screen caused greater frequency of asthenopic symptoms such as headache, fatigue, eye ache, tearing, diplopia, eyestrain and red eye. Most participants demonstrated blink rates of 6–10 blinks/minute in both conditions. Low blink rates (1–5 blinks/minute) were more frequent during soft copy reading, whereas intermediate rates (11–15 blinks/minute) were more common during hard copy reading.

Conclusion:  Reading from digital devices is associated with higher convergence demand and greater frequency of asthenopic symptoms compared to hard copy. Soft copy reading showed a trend toward lower blink rates, which may contribute to ocular discomfort.