Now is an era of computer whether desktop,kptop,ipod,or mobile we spent much time on computer or digital screen.Computer Vision Syndrome (CVS),also referred to as digital eye strain, describes eye and vision-related problems that result from prolonged computer, tablet, e-reader and cell phone use.The medical term "CVS " for digital eye strain, is best avoided by being aware of it. CVS more commonly seen in computer professionals and students. CVS which is also known as digital eye strain is caused due to prolonged hours of exposure to digital devices like computer screens, laptops, smartphones and video games. Doctors stressed on taking frequent breaks, using lubricants and anti glares glasses
 
       Many individuals experience eye discomfort and vision problems when viewing digital screens. The level of discomfort appears to increase with the amount of digital screen use.The main visual symptoms reported by visual display terminal (VDT) users include eyestrain, tired eyes, irritation, burning sensation, redness, blurred vision, and double vision, thus termed the phrase ‘computer vision syndrome’ (CVS).

       Vision problems and symptoms associated with the use of the eyes are the most frequently occurring health problems among VDT users. CVS not only causes pain and discomfort to the individual, but also reduces overall efficiency by reducing the time that a person can effectively work.Majority of VDT patients had symptoms that were different than other near-point workers, especially as related to glare, lighting, and spectacle requirements.

            Greater frequency and severity of symptoms were also noted. One study shows higher degree of meibomian gland dysfunction (MGD) in symptomatic computer users than in computer users who have lesser degrees of ocular surface complaints.Occupational Safety and Health Administration of the US Government (OSHA) has defined CVS as a ‘complex of eye and vision problems that are experienced during and related to computer use; it is repetitive strain disorder that appears to be growing rapidly, with some studies estimating that 90% US workers using computers from more than three hours per day experience CVS in some form.’

             Office work involves a range of activities including typing, reading, and writing. Each activity was adequately varied in the requirements of posture and vision.Computers have combined these tasks to where most can be performed without moving from the desktop, thereby improving quality, production, and efficiency. The popularity and affordability of personal computers with the internet capabilities at home introduced more computer users.

         Studies have not clearly indicated a negative effect on computer user due to radiation levels from VDTs.VDTs are known to emit many types of radiation, including soft X-radiation, optical radiation, radiofrequency radiation, very low frequency radiation, and extremely low frequency radiation. Most women in offices, who work with VDTs, do not increase their risk of miscarriage.

       It may well be that high computer usage raises the number of dry eye sufferers and/or increases the severity of symptoms, but studies have not produced any direct comparison of groups that would allow us to conclude that computer use bears a long- term causal relation to ocular surface disease.There needs to be more prospective studies to elucidate direct relationship between ocular surface disease (e.g. MGD) and CVS.

Source: National Health Survey