[Changes in visual function caused by work at a data display terminal]

Area of Science:

• Ophthalmology
• Occupational Health
• Ergonomics

Background:

• Video display terminal (VDT) use is prevalent in modern workplaces, posing potential risks to visual and musculoskeletal health.
• Previous research suggests VDT work may induce visual discomfort and potentially alter visual functions.

Purpose of the Study:

• To prospectively investigate the influence of VDT work on the visual system over a five-year period.
• To compare visual function parameters between VDT workers and a matched control group of non-VDT office workers.

Main Methods:

• A 5-year prospective, matched-pairs study involving 102 VDT workers and 102 controls.
• Comprehensive visual examinations including visual acuity, phorias, stereopsis, color vision, slit-lamp biomicroscopy, funduscopy, tear film stability (break-up time), lacrimal secretion (Schirmer-I test), visual field testing (perimetry), and intraocular pressure measurement (tonometry).

Main Results:

• A significant association was found between asthenopia and daily VDT work duration, with those working >6 hours reporting more symptoms.
• While pre-existing exophoria showed a trend toward increase in VDT users, this was not statistically significant.
• No statistically significant differences were observed in any of the standard screening visual parameters between the VDT group and the control group after five years.

Conclusions:

• Daily VDT work duration is a significant factor for asthenopia, highlighting the importance of work-hour management.
• Standard visual screening examinations may not detect subtle, long-term changes induced by VDT work.
• Further research is needed to understand the long-term visual effects of VDT use, especially concerning binocular vision and accommodation.