Analysis of the Outcomes of the Screen-Time Reduction in Computer Vision Syndrome: A Cohort Comparative Study

PURPOSE: To analyze the outcomes of screen-time reduction on the foveal responses that associates computer vision syndrome (CVS) using multifocal electroretinogram (mfERG) examination. METHODS: This prospective multicenter cohort comparative study included 49 eyes of 49 medical students divided into two groups. Group A (control group) included 25 eyes with no CVS diagnosis while group B (CVS group) included 24 eyes with CVS diagnosis. All students responded to the valid and reliable CVS-Form 3 (CVS-F3) questionnaire and underwent complete ophthalmic and mfERG examinations twice at the time recruitment in the study and four weeks after strict reduction of the daily screen-hours to ≤1 screen-hour daily to document associated foveal responses. RESULTS: We documented statistically significant reduction in foveal responses in CVS versus control groups in mean mfERG Rings 1, 2, and 5 with Quadrants 1, 2, and 4 (P=<0.0001, 0.0001, 0.0003, 0.001, 0.002, and 0.006, respectively). Following the screen-time reduction, the second mfERG examination revealed significant post-reduction improvements in foveal responses in CVS group particularly in mean mfERG Rings 1, 2, 3, and 5 with Quadrants 1 and 4 (P=<0.0001, <0.0001, 0.0005, 0.02, <0.0001, and 0.04, respectively). CONCLUSION: This study documented the screen-induced foveal dysfunction that associates CVS using mfERG examination, which revealed remarkable significant improvements in foveal responses in the 4 weeks following strict screen-time reduction. These improvements were also associated with corresponding improvements in the visual performances. We suggest that the potential screen-induced foveal dysfunction outcomes might be reversible with strict screen-time reduction. We also recommend that educational institutional policies should limit online education-hours and redesign the mandated computer system use program to guard against visual sequelae of CVS. CLINICAL TRIALS REGISTRATION: ClinicalTrials.gov (ID: NCT04405648).