Effect of blue cut glasses on color discrimination and contrast sensitivity in young emmetropes

Objective: To evaluate the effects of blue-cut glasses on visual functions, specifically color discrimination (CD) and contrast sensitivity (CS), in young emmetropes. Methods: This interventional study was conducted at Hayatabad Medical Complex and Pakistan Institute of Community Ophthalmology, Peshawar, Pakistan, from 10-09-2022 to 10-04-2023. A total of 80 emmetropes aged 18–30 years with 6/6 vision were included, while individuals with ocular or systemic conditions affecting vision were excluded. Visual functions were assessed using the Ishihara test for color blindness, Pelli-Robson chart for contrast sensitivity, and FM 100 Hue test for color discrimination. Participants were tested with and without blue-cut glasses in randomized sessions to avoid fatigue or memorization effects. Data were analyzed using paired t-tests, with a p-value of <0.05 considered statistically significant. Results: A total of 80 participants (55% male, 45% female) with a mean age of 25.37±2.99 years were included. Mean color discrimination (CD) score was 27.35±26.99 with non-blue-cut glasses and 34.05±28.33 with blue-cut glasses, showing a statistically significant difference (p = 0.004). The mean contrast sensitivity (CS) score was 1.92 ± 0.07 without blue-cut glasses and 1.91±0.08 with blue-cut glasses, with no statistically significant difference (p = 0.117). These findings indicate that blue-cut glasses negatively affect color discrimination but have no significant impact on contrast sensitivity. Conclusion: Blue-cut glasses negatively impact color discrimination while showing no significant effect on contrast sensitivity in young emmetropes. These findings highlight the importance of evaluating the trade-offs between the protective and visual effects of blue-cut glasses.