There appears to be a significant link between visual field abnormalities and heavy computer use.

Its exact cause is unknown, although potential risk factors, including smoking and high blood pressure, have been suggested. The link to heavy computer use, especially among people who are near-sighted, is described in the Journal of Epidemiology and Community Health.

The research team tested the sight of workers in four different Japanese companies, employing over 5000 people each.

Years of Use, Length of Sessions

In all, some 10,000 workers, with an average age of 43, were randomly selected for testing as part of a general medical check-up. They also completed questionnaires about their computer use, both at home and at work, and any history of eye disease.

Computer use was categorized in blocks of five years, ranging from less than five years, to more than 20 years, as well as the average amount of time spent at the screen per session, ranging from 1 hour to more than 8 hours at a time. Those classified as heavy users tended to be men and younger.

The test revealed that 522 (5.1%) employees had visual field abnormalities. And there appeared to be a significant link between these and heavy computer use among those with either long or short sight, collectively known as “refractive errors.”

Near-Sighted People May Be More Vulnerable

An in-depth eye test pinpointed revealed that around a third of these workers (165) had suspected glaucoma, characterized by distinct visual field abnormalities. And there also appeared to be a significant link between these and heavy computer use among workers who were near-sighted.

In fact, the most common refractive error was near-sightedness, leading the authors to speculate that the optic nerve in near-sighted eyes might be more vulnerable to computer stress than it is in normal eyes.