Computer users at risk of eye disease!!

Scientists issue a technology health warning after finding the first concrete evidence of a threat to users’ eyesight.




The first health warning for people who work with computers has followed a study that shows an increased risk of glaucoma in short-sighted people.



The chance of developing the eye disease that can lead to blindness is almost doubled in short-sighted intensive computer users.

Glaucoma is a disease of the eye triggered by high pressures within the eyeball. The danger is that this pressure will exceed that in the small blood vessels inside the eye, preventing blood flow to the optic nerve and causing damage. The disease has no symptoms and develops insidiously, because the nerve fibres that are the first to suffer damage come from the periphery of the retina. Patients may suffer loss of peripheral vision without even being aware of it.

A team from Toho University School of Medicine in Tokyo says that the risk is limited to people who are already short-sighted. Those with normal vision are not at risk, according to its research.

Since computers came into widespread use there have been many studies of possible impact on vision, but few have found any ill-effects. Users may suffer eye strain and headaches, but no long-term effects have previously been identified. So the Japanese study, published in the Journal of Environmental and Community Health, will be a cause for concern. The team studied more than 9,000 Japanese workers from the electronics and steel industries, some of whom worked intensively with computers and some of whom did not.

All were screened for visual field abnormalities, an early warning of glaucoma. Just over 500 of them were found to suffer abnormalities and of these 315 were examined in more detail by an ophthalmologist. Two thirds of them were found to have the changes characteristic of glaucoma.

They were also asked about how many hours they spent on a computer and for how long they had been doing it. By multiplying the time spent at the screen by the years that they had been doing it, the workers were classified into three groups; light, moderate and heavy users. After correcting for other factors, such as a family history of glaucoma, the team found that among short-sighted people who were heavy computer users, the risks of glaucoma were 82 per cent higher.

Short sight has been identified in the past as a risk factor for glaucoma. The team speculates that the optic nerve in myopic eyes may be more susceptible to damage than in normal eyes and that using a computer intensively may be the cause of such damage.

“Computer stress is reaching higher levels than have ever been experienced before,” Dr Masayuki Tatemachi said. “In the next decade, therefore, it might be important for public health professionals to show more concern about myopia [short sight] and visual field abnormalities in heavy computer users.”

A suprising finding is that in normally sighted people the risk of glaucoma actually decreases the more intensively they use the computer, as do the risks of other eye diseases such as cataract or diabetic retinopathy.

David Wright, chief executive of the International Glaucoma Association in Britain, said: “This is the first evidence of a link between computers and glaucoma, but the widespread use of computers is at unprecedented levels and it is reasonable to expect some effect on the visual system.”

He added: “I think that there are two extremely valuable points that need to be emphasised. First, anyone involved in heavy computer use should receive regular comprehensive eye examinations to detect the earliest possible signs of the development of glaucoma, when treatment is most effective.

“Secondly, it will be important to follow this study with further research to establish the validity of this initial indication of a potential problem.”

Take regular breaks, every 20 minutes or so. There should be sufficient space behind the screen to look beyond it and relax the eyes



Screens should be clean, adjusted for brightness and contrast to the most comfortable setting and ideally placed so that light comes in from the side rather than in front or behind the screen

Ensure that you wear glasses that correct any defects of vision. Employers are obliged to provide free eye tests for regular users and pay for glasses if it is found that these are required for using a computer screen

Regular checks are vital for early detection. Only one glaucoma test is mandatory part of the eye test — the visual examination of the optic disc. This will only find 25 per cent of glaucomas

Two additional tests needed to achieve the best practical detection of glaucoma; either tonometry, a measurement of the pressure inside the eye, or perimetry, which checks for visual field anomalies .