Stop Eye Strain!
21 June 2010
Read by 1773 persons
Headaches, eye irritation. Eye strain is a daily problem for many computer workers. To cope with it, eye treatment and some workplace changes can help keep you in good shape!
An increasingly essential element of the modern world, computers are part of the daily lives of millions of employees. But screen work is accused of causing visual problems, dry eyes, etc. What is the reality? Doctissimo takes stock under the watchful and expert eye of Professor Jean-Claude Hache, president of the scientific society for eye correction.
There is fatigue and fatigue.
Fatigue related to screen work is directly proportional to the time spent in front of the screen but also to the quality of the observer's vision. This sensation can take three forms:
• Visual fatigue: This is the most frequent phenomenon with the feeling of no longer being as efficient in terms of vision and intellectually. It is rarely a decrease in acuity, but more often a binocular imbalance with impressions of images that double or become blurry. This type of fatigue appears more frequently if ametropia or presbyopia is not corrected;
• Eye strain: Itching eyes, irritation, dry eye sensations. These characteristic signs are related to insufficient tear secretion, which is particularly unpleasant. Normally, the blink rate is around 12 to 20 per minute, allowing the formation of a new tear film before the previous one breaks. But screen work is associated with a decrease in this frequency and therefore a drying of the eye surface;
• General fatigue: This latter manifests itself through headaches, but also spinal pain (backache) related to posture problems. Fatigue can also have a direct influence on the quality of the work performed. Thus, several studies show a deleterious impact on efficiency defined by reading rate and the ability to integrate information. This parameter can be assessed using a photo-oculograph (or gaze tracker), which allows the measurement and analysis of the direction of gaze by recording the eye path when following a moving target or exploring a text. Result: this efficiency decreases as the duration of screen work increases. An argument for not leaving work too late.
More often a revealer of visual problems.
If screen work time is too long, fatigue may appear due to focusing on the screen but also to immobility related to postural problems. But fatigue can also occur much earlier if the person suffers from an uncorrected visual disorder, mainly astigmatism or hypermetropia. In cases of latent hypermetropia occurring between 30 and 40 years of age, fatigue occurs more frequently and more quickly. This type of work then acts as a revealer of this visual disorder associated with blurred near vision while distant vision remains correct. If the hypermetropia is mild, it may go unnoticed. More important, it can lead to convergent strabismus, significant visual fatigue and headaches.
When the two images from the two eyes no longer overlap exactly, people may suffer from heterophoria (tendency to strabismus). Strabismus refers to the lack of parallelism between the optical axes of the two eyes when fixing a point. The origin of strabismus can be related to high hypermetropia or hereditary origin. Depending on the age at which it is treated, its treatment varies between glasses and eye exercises or surgery. Myopia can, however, go unnoticed because near vision (specific to screen work) is unchanged, unlike distance vision. Occupational physicians are particularly attentive to these problems. They will not hesitate to send their patient to an ophthalmologist if they suspect visual problems or associated pathology.
Towards our anti-fatigue advice!
To avoid this phenomenon of visual fatigue, it is of course advisable to correct your eyesight with appropriate solutions: glasses (with near vision lenses, also called interview lenses, for presbyopes), contact lenses (better adapted today) or refractive surgery for myopia. Then, some common sense measures can improve your work environment:
• Avoid reflections on the screen. The use of anti-glare filters should only be used if other adjustments are impossible, as they can reduce contrast and ultimately hinder reading;
• The field of vision should not contain windows or direct light sources to avoid glare. The screen should therefore be perpendicular to the light source;
• Use blinds or curtains to prevent reflections;
• Prefer indirect (halogen) or individual (desk lamp) light sources. Ceiling lights with framed light sources (with grids limiting reflection problems);
• Take breaks and prioritize task alternation. A change of activity (or moments of non-fixation of the screen) should occur either 5 minutes for 45 minutes of work, or 15 minutes every two hours according to experts. But small visual breaks every 15 minutes can also do the trick.
Such advice can improve the general situation of visual fatigue. At the congress of the French Society of Ophthalmology (SFO), a study conducted on 465 patients suffering from visual fatigue was presented by Dr. Claude Speeg-Schatz, ophthalmologist in Strasbourg. After following the basic advice, more than half of the employees saw their situation improve. The persistence of visual fatigue in others is probably due, according to the authors, to a failure to follow the advice given by the occupational physician, a lack of ergonomic correction of the workstation or the lack of consideration of changes in blinking. These results highlight the need for good coordination between occupational physicians and ophthalmologists to effectively combat visual fatigue.
But research is no longer focusing solely on the eye-screen duo but rather on the new body-eye-screen trio. Recent research in neuroscience has highlighted that posture and therefore the direction of gaze can influence the perception of information.
Published February 10, 2009
Posted online June 21, 2010
doctissimo
An increasingly essential element of the modern world, computers are part of the daily lives of millions of employees. But screen work is accused of causing visual problems, dry eyes, etc. What is the reality? Doctissimo takes stock under the watchful and expert eye of Professor Jean-Claude Hache, president of the scientific society for eye correction.
There is fatigue and fatigue.
Fatigue related to screen work is directly proportional to the time spent in front of the screen but also to the quality of the observer's vision. This sensation can take three forms:
• Visual fatigue: This is the most frequent phenomenon with the feeling of no longer being as efficient in terms of vision and intellectually. It is rarely a decrease in acuity, but more often a binocular imbalance with impressions of images that double or become blurry. This type of fatigue appears more frequently if ametropia or presbyopia is not corrected;
• Eye strain: Itching eyes, irritation, dry eye sensations. These characteristic signs are related to insufficient tear secretion, which is particularly unpleasant. Normally, the blink rate is around 12 to 20 per minute, allowing the formation of a new tear film before the previous one breaks. But screen work is associated with a decrease in this frequency and therefore a drying of the eye surface;
• General fatigue: This latter manifests itself through headaches, but also spinal pain (backache) related to posture problems. Fatigue can also have a direct influence on the quality of the work performed. Thus, several studies show a deleterious impact on efficiency defined by reading rate and the ability to integrate information. This parameter can be assessed using a photo-oculograph (or gaze tracker), which allows the measurement and analysis of the direction of gaze by recording the eye path when following a moving target or exploring a text. Result: this efficiency decreases as the duration of screen work increases. An argument for not leaving work too late.
More often a revealer of visual problems.
If screen work time is too long, fatigue may appear due to focusing on the screen but also to immobility related to postural problems. But fatigue can also occur much earlier if the person suffers from an uncorrected visual disorder, mainly astigmatism or hypermetropia. In cases of latent hypermetropia occurring between 30 and 40 years of age, fatigue occurs more frequently and more quickly. This type of work then acts as a revealer of this visual disorder associated with blurred near vision while distant vision remains correct. If the hypermetropia is mild, it may go unnoticed. More important, it can lead to convergent strabismus, significant visual fatigue and headaches.
When the two images from the two eyes no longer overlap exactly, people may suffer from heterophoria (tendency to strabismus). Strabismus refers to the lack of parallelism between the optical axes of the two eyes when fixing a point. The origin of strabismus can be related to high hypermetropia or hereditary origin. Depending on the age at which it is treated, its treatment varies between glasses and eye exercises or surgery. Myopia can, however, go unnoticed because near vision (specific to screen work) is unchanged, unlike distance vision. Occupational physicians are particularly attentive to these problems. They will not hesitate to send their patient to an ophthalmologist if they suspect visual problems or associated pathology.
Towards our anti-fatigue advice!
To avoid this phenomenon of visual fatigue, it is of course advisable to correct your eyesight with appropriate solutions: glasses (with near vision lenses, also called interview lenses, for presbyopes), contact lenses (better adapted today) or refractive surgery for myopia. Then, some common sense measures can improve your work environment:
• Avoid reflections on the screen. The use of anti-glare filters should only be used if other adjustments are impossible, as they can reduce contrast and ultimately hinder reading;
• The field of vision should not contain windows or direct light sources to avoid glare. The screen should therefore be perpendicular to the light source;
• Use blinds or curtains to prevent reflections;
• Prefer indirect (halogen) or individual (desk lamp) light sources. Ceiling lights with framed light sources (with grids limiting reflection problems);
• Take breaks and prioritize task alternation. A change of activity (or moments of non-fixation of the screen) should occur either 5 minutes for 45 minutes of work, or 15 minutes every two hours according to experts. But small visual breaks every 15 minutes can also do the trick.
Such advice can improve the general situation of visual fatigue. At the congress of the French Society of Ophthalmology (SFO), a study conducted on 465 patients suffering from visual fatigue was presented by Dr. Claude Speeg-Schatz, ophthalmologist in Strasbourg. After following the basic advice, more than half of the employees saw their situation improve. The persistence of visual fatigue in others is probably due, according to the authors, to a failure to follow the advice given by the occupational physician, a lack of ergonomic correction of the workstation or the lack of consideration of changes in blinking. These results highlight the need for good coordination between occupational physicians and ophthalmologists to effectively combat visual fatigue.
But research is no longer focusing solely on the eye-screen duo but rather on the new body-eye-screen trio. Recent research in neuroscience has highlighted that posture and therefore the direction of gaze can influence the perception of information.
Published February 10, 2009
Posted online June 21, 2010
doctissimo
