|Title||WILL VISUAL DISCOMFORT AMONG VDU-USERS CHANGE IN DEVELOPMENT WHEN MOVING FROM SINGLE VISION LENSES TO SPECIAL DESIGNED VDU-PROGRESSIVE LENSES?|
|Author, Co-Author||Gunnar Horgen, Arne Aaras, Magne Thoresen|
|Abstract|| PURPOSE: Three types of optometric corrections specially designed for VDU-work ("VDU-progressives") and one single vision lens were compared in a prospective field study to investigate if these lenses created a difference in the development of visual discomfort compared to single vision lenses
(SV) when working on an optimized VDU-workstation?
METHODS: The study has a prospective, parallel group design, with four groups of VDU-workers. Approximately 40 subjects in each group, selected after careful task analysis with special attention towards the visual angles and distances to the work tasks. The groups were followed over one year. A questionnaire concerning visual conditions, working conditions, discomfort in different body areas, the status of the subjects' optometric corrections, psychological factors both at work and at home, amount, frequency and duration of VDU-work etc. was filled in before the intervention, after six months and after one year. No other contact was made with the subjects. The VDU-lenses included were Interview (I) (Essilor), Gradal RD (R) (Zeiss) and Technica (T) (American Optical). Pain intensity and duration were assessed on a 10 cm. Visual Analogue Scale before the intervention, and six and twelve months after the intervention. All subjects were given a complete optometric examination.
RESULTS: Only small changes in the development of headache and visual discomfort were registered. However, the subjective evaluation of area of clear vision and overall satisfaction was significantly improved for the I and R lens (P<0,05). There were no significant changes for T and SV lenses.
CONCLUSIONS: Lens designs that cover viewing distances from near and out to approximately 2 meters works well compared to SV lenses and lens designs trying to cover greater depth of focus than this.
ADDITIONAL COMMENTS: This research is supported financially by The Norwegian Optometric Research Institute, and Buskerud College, Dep. of Optometry.
|Affiliation of Co-Authors||Alcatel AS, University of Oslo Section for Medical Statistics|