Device use has skyrocketed since the onset of the global pandemic, resulting in eye strain and damage as we spend the additional time we saved from our daily commute on social media, reading the news, or playing games on our phones.

If you are wondering why you have a sudden onset of headaches and itchy/dry eyes, the culprit is likely to be your brightly-lit mobile and device screens. We had the pleasure of interviewing Dr. Lili Liang to share her insights on how we can protect our eyes, alleviate eye strain, and identify when we would need to seek medical attention if the health condition intensifies.

L = Dr. Lili Liang

It has been reported in various publications of how mobile device usage has gone up during covid, some reporting as much as a 200% increase in the time spent on their phones. Have you seen more cases of ocular strain as a result of this?

Definitely. A few weeks into the shutdown, I started getting telehealth consultation requests from patients complaining of increased headaches, blur, or eye fatigue that they did not notice before. Now during in-person eye exams, most patients report symptoms of ocular strain along with increased screen time.

What causes ocular strain?

L: Our eyes are just like cameras. They function based on the same mechanisms. In a camera, you have the lens that determines the focal length enabling you to shoot at a far distance. We have that too. It is the lens that we are born with. We also have the zooming mechanism that cameras have when we want to shoot close up photos of objects. It is similar to the autofocus on our phone cameras where when you tap on the screen, it automatically adjusts according to the distance of the object. Our eyes do the exact same thing. The zooming mechanism that our eyes have is controlled by the ocular muscles. Whenever we look at things close up like phones, computers, tablets, etc, those eye muscles are flexed. We don’t control those muscles. These muscles contract automatically as a reaction to focus on objects up close. If you are staring at the screen for 8-10 hours a day, your eye muscles are flexed the entire time. Just like any muscles in the body, they can get tired or sore after being overworked. This is the first time in the history of mankind that we are all spending so much time on screens, for work, and for leisure. Our visual system can get tired from operating at such a near range for prolonged periods of time. When these focusing muscles cannot sustain the workload anymore, it manifests as headache, strain, trouble focusing, or eye fatigue that you may have noticed tend to happen towards the end of the day.

What are some initial symptoms of ocular strain?

L: When we work on a screen, we tend to be staring with little ocular movement or blinking. One of the initial signs of eyes being overworked is dry eyes. Dry eyes can start off as tearing a lot as a way for the eyes to fight off the dryness by producing excess tears. For others, dry eyes can present as a stinging or burning sensation of the eyes. For some, dry eyes can be a sandy, gritty feeling in the eyes. Along with it, you can also experience trouble focusing or blurriness. When the focusing muscles are sore, you can experience ocular strain as pressure over the front of the eyes or temple area.

What would indicate that we have severe ocular strain and should seek medical attention?

L: You should seek medical attention at the early signs. You don’t want it to build up and progress into headaches or constant ocular strain where it affects your productivity and quality of life. However, if you are experiencing headaches, having trouble focusing up close, or seeing double, it means your ocular strain is significant and your visual system is asking for help.

What can we do to minimize ocular strain?

L: The best way to minimize ocular strain is prevention. It is very simple. Follow the 20/20/20 rule. For every 20 minutes of screen time, stare into space 20 feet away for 20 seconds. The idea is to sneak in little breaks which allows your focusing muscles/zooming mechanism to relax. It’s like taking a break in between your reps when you are at the gym. You rest for your muscles to recover so you can continue on with your next set. Regular little breaks are more useful than a 30 minutes break after 2 hours. You really just need a 20-second break every 20 minutes.

Following the 20/20/20 rule is the quickest way to reset the eyes. Your eyes naturally blink when you remove your gaze from the screen which improves dryness. Your eye muscles also naturally relax when you look far away reducing ocular strain.

How can we protect our eyes given we still have to work and be in front of a computer or mobile device all day?

L: There are two aspects when we work on the screen. One is dryness coming from staring at the screen which causes our eyes to blink less often. The other is the stress on the focusing/zooming mechanism. Other than following the 20/20/20 rule, the root cause of ocular strain needs to be addressed. We, unfortunately, cannot escape from using screens but we can give our visual system the support it needs. If your camera is unable to take clear pictures to close up, you fix the focusing mechanisms. Similarly, If the focusing system of our eyes is unable to sustain the workload, you give it some help. This is where a close-up glasses prescription comes into play. Imagine me putting up a pair of focusing lenses in front of your right now as you read this article. These lenses would take over and do the focusing work for you. Your visual system would naturally be less stressed when the workload is reduced. It is similar to having a spotter at the gym who is there to help you out when you get stuck. Unfortunately, our eye focus muscles are not trainable. They do not get stronger by working them harder. We can only give them the appropriate prescription lenses to relieve them from being overworked.

What is the effectiveness of using a blue light lens?

L: Determining whether you need a prescription for close up is more important than having the blue light filter. As illustrated before, treating the root cause of a tired focusing system is what is most effective in minimizing ocular strain.

However, do blue light filters block out blue light? Without a doubt yes, as long as they are from a trusted manufacturer. Blue light has been proven to be more harmful to the eyes. To block out the blue light which is what is mainly emitted from screens is a logical scientific step to take in preventative medicine. However, what is undetermined is how detrimental could this extra blue light exposure be to our ocular system. That will take longer to prove to become evidence-based medicine. Looking at the example of nicotine use, it also took a while to fully understand the pathophysiology of nicotine use on the respiratory system, fetal development, and its relationship to lung cancer. By the time science has caught up, damages are already done. The idea to be proactive to protect ourselves based on what we know so far is preventative medicine. That is what a blue light filter is to me. I recommend blue light filters, not based on evidence-based medicine we have so far, but based on preventative medicine. I encourage my patients to try them, especially if they are on the screen a lot. We have demo blue light filter lenses in the office where you can experience the filter on the screen. Generally, patients who need that focusing prescription for close up notice the difference blue light filters make. It is always nice to apply that blue light filter on top of a reading prescription to give extra comfort.

Any additional ways we can take care of our eye health such as foods, nutrients, exercises, etc. that you would recommend?

L: Other than addressing the ocular strain issue which is one aspect of the eyes, there is also the health of the ocular tissues. I always tell my patients, whatever is good for the body is also good for the eyes. We all know to eat green leafy vegetables, to not smoke, and to protect ourselves from UV exposure. Those are all applicable to the eyes. Highly pigmented foods are filled with Lutein and zeaxanthin which are soldiers that protect our macular area. The macula is the center of our vision which provides the highest acuity. A common condition that compromises the macula is macular degeneration. Smoking is a risk factor for developing macular degeneration. Overexposure of UV not only increases the risk of malignant growth on the eyelid and ocular surface but also accelerates cataract formation. If you are a young, healthy individual, you can get all the appropriate nutrients that are good for the eyes straight from a natural balanced diet. You don’t need to take any eye-specific supplements. It is only in the elderly population or those who are showing early signs of changes that would need specific supplements to stabilize and prevent further deterioration of the ocular tissue.

ABOUT DR.LILI LIANG

Dr. Lili believes that there is a story behind every person and that a little bit of micro-dancing to samba jazz doesn’t hurt anybody. She holds a degree in Doctor of Optometry and a Master of Public Health. Through her experience from Malawi to Peru to now Vancouver, she strives to understand her patients on a personal level as she serves as the neighbourhood optometrist in Gastown and Mount Pleasant.

Website: www.doctorlili.com

Social: @whatlilisees