Reliance on digital devices for work, school and leisure time may have been a reality for some of us prior to the COVID-19 pandemic, but the months spent in quarantine have greatly increased the amount of time we all spend on our devices. Over the past year, many of my patients have asked me whether the long hours spent on their computers are damaging their eyes. The short answer to this is yes - but the good news is that there are tools and strategies you can use to limit the effect of screen time on your eyes!
Digital eye strain or computer vision syndrome often looks like this: your eyes are red, tired, irritated, maybe watery, you get headaches often centred in or around the eyes (though you may also feel it around your temples or the back of your head and neck), and your vision feels blurry especially when looking away from your computer screen. Sound familiar?
Let’s break down some of the reasons why those symptoms are occurring:
Reduced blink rate causing tear film disruption: when using a digital device, we tend to blink about half as often as we would otherwise! For clear and comfortable vision, your eyes rely on a basal level of tears, also called the tear film. The tear film is made up of several components, the balance of which is important to maintain a healthy ocular surface. The action of blinking causes fresh tears to be released and spread over the surface of your eyes as well as the drainage of tears. So you can imagine how a decreased blink rate can interfere with these normal processes. If you have pre-existing dry eye, the effect is even more exaggerated.
Accommodative stress and uncorrected refractive error: when focusing on a near target (ie. your device screen), several muscles within and around the eyes are constantly being used. Accommodation is the process of engaging these muscles in order to focus clearly. After prolonged time using a digital device, your ability to properly accommodate diminishes due to fatigue. This can cause your computer screen to become blurry, causing you to squint or adjust your distance from the screen in order to continue working. When looking away from your screen, your distance vision may also be blurry due to strain and fatigue to your visual system. In addition, if you have any uncorrected refractive error - near sightedness, far sightedness, astigmatism, or presbyopia (age-related need for reading glasses) - the strain on your vision will be multiplied.
Glare from your screen and room lighting: the brightness, contrast and colour temperature settings for your screen can have an effect on the amount of strain your eyes experience. If the contrast is low, you will be more likely to squint at what you are looking at. Remember the decreased blink rate? Studies have shown that with low contrast and low image quality, your blink rate will decrease even more. The brightness of your screen and room lighting are also important factors. If your workplace setup is causing excess glare on your screen, your vision will likely feel more strained. Our digital device screens also emit high energy blue light, which tends to scatter more inside the eye. This can increase eye strain. The blue light also affects melatonin production, which can interfere with our sleep cycle.
So what can you do to improve this situation?
Follow the 20-20-20 rule. Every 20 minutes, take a 20 second break and look at something 20 feet away. During these breaks make sure to blink you eyes fully and close your eyes as well. This will allow your eyes' focusing system to relax, thereby reducing fatigue throughout the day. Blinking also stimulates the release of fresh tear film components, which will decrease those dry eye symptoms. I often tell my patients to take these breaks more often, but the 10-20-20 rule just doesn’t have the same ring to it!
Treat your underlying dry eye - I can help you with that!
Wear glasses while working on your computer. Even if your glasses prescription is mild and only worn part time, they may help reduce your eye strain! It may also be appropriate to wear a glasses prescription specifically designed for computer use. Every case is different - we will determine which option is best for you during your next eye exam.
Filter the blue light from your screen. This can be achieved through lenses designed to block out the blue light or by adjusting your screen settings.
Adjust your workspace to minimize glare. The brightness of your screen should match the brightness of the room (ie. you should avoid viewing a bright screen in a dark room and vice versa).
Long story short, if you relate to this post and think you may be suffering from digital eye strain, it's likely time to get your eyes checked!