Young non-VDU users are more susceptible to ocular functions changes with sustained VDU nearwork

Abstract

Purpose: This study investigates the change in ocular function among young schoolchildren following nearwork with and without visual display units (VDU). Methods: Thirty-one young schoolchildren played computer game (VDU work) and paper game (non-VDU work) continuously for 2 h at 40 cm. Non-invasive tear break up time (NIBUT), blinking rate (BR) and palpebral aperture size (AS) were measured before and after VDU work and non-VDU work. Reading for NIBUT, BR and AS were normalized by converting into log 10 unit. Results: MANCOVA analysis shows that logNIBUT is significantly reduced after both nearwork (F 1,49 = 58.10, p < 0.01) but not for log BR and log AS (p > 0.01). Pairwise comparison shows that modes of nearwork produce significant different effect in post-task log BR (F 1,53 = 7.13, p = 0.01) and log AS (F 1,53 = 11.00, p < 0.01). VDU work produces lower BR and larger AS while Non-VDU work does not change the BR but is associated to a smaller AS. Conclusions: Sustained 2-h VDU work and non-VDU work produces significant reduction in NIBUT measurements. Modes of nearwork differently change the post-task BR and AS. Young schoolchildren are more susceptible to VDU nearwork effect. © 2011 Spanish General Council of Optometry.