Are there differences between 'visual symptoms' and specific ocular symptoms associated with video display terminal...

To assess the reliability of self-reported symptoms of asthenopia associated with VDT use (as characterized by general visual symptoms, headache and specific ocular symptoms) for both continuing soft contact lens (SCL) wearers and former SCL wearers who had undergone successful laser-in-situ-keratomileusis (LASIK) surgery.

Forty generally healthy adults, aged between 24 and 44 years, were asked to complete a 13 page questionnaire that included requests for information on general visual symptoms, headache and specific ocular symptoms such as dry eye associated with VDT use. The adults were either long term successful soft contact lens wearers (n=20) or a similar group who had then undergone successful LASIK refractive surgery for myopia 2 years prior to the questionnaire being provided.

Most subjects (70%) reported experiencing some visual symptoms sometimes, 62.5% reported headaches sometimes, and 82.5 % reported specific ocular symptoms sometimes. There were no obvious differences between the two groups either in the reported frequency or severity (by visual analogue scale, VAS) of visual symptoms, headache or specific ocular symptoms. However, while the reporting of headache showed no obvious association with the number of specific ocular symptoms reported, the latter showed a clear correlation with the reporting of the severity of visual symptoms (p<0.001).

The results indicate that when an individual reports visual symptoms, they may actually be providing recall of specific ocular symptoms. Therefore, contrary to an often common practice, visual symptoms should be assessed separately to specific ocular symptoms such that the appropriate management can be selected. The results also indicate that previous contact lens wearers who have undergone successful LASIK are still likely to experience some visual and specific ocular symptoms when undertaking computer based work on a regular basis.