Computer Vision Syndrome [CVS].

Computer Vision Syndrome is a topic that has become relevant now that more & more people are working from home as part of the measures to contain Covid.  This has resulted in many more hours spent in front of a screen (computer, phone, or tablet), in most of the cases.

I posted an article on blue light in July 2020, and there will be some overlap, but the subject needs to be emphasized.  CVS is defined when a person spends more than 3 continuous hours in front of a screen.  The reality is most people spend closer to 8 hours a day with few breaks in between.  I will list the effects of CVS and end off with some suggestions.  Remember this is a marathon, not a sprint; so every small measure you implement will have a profound effect in the long term.

Recapping light-the sun emits visible & invisible light.

Visible light-think 7 colours of the rainbow with each colour having a different energy.

Invisible light: from the blue side of the spectrum we have UV (ultra-violet), X-Rays, Gamma Rays & Cosmic Rays-these are all high energy.

From the red side of the spectrum we have infrared, microwave, radar, radio etc.

Diagram  Description automatically generated

The take home message on the BLUE LIGHT part that contributes to CVS, is that although UVA can give you sunburn, and UVB can cause skin cancer, these invisible, higher energy rays do not penetrate as deeply into the eye as visible blue light does.  And all screens emit visible blue light.  Prolonged exposure to this blue light will cause a dry eye, it will mess with your internal clock (see my article on blue light from July 2020), and as also been linked to macular degeneration (one of the top 3 causes of blindness), as well as cataracts. 

Then there are all the other factors linked to CVS:

POSTURAL which affect the neck, wrist, and rotator cuff muscles as well as the hip flexor and related hip muscles.  See your biokineticist or related professional for more information.   

PSYCHOLOGICAL: from excessive fatigue, depression etc.  These factors do not work in isolation, and are easy to understand when seen in the big picture of less social interaction, sleep deprivation etc.


Some of the suggestions listed below may sound simple, but many are the fruit of research into Myopia Control (the PC word for this is Myopia Management), and I have posted articles on this subject.  If you are a parent, this is an important subject to read & understand.  Our Orthokeratology or Ortho-K overnight wear lens is related to this.  So the advice is based on good research.

  1. Lubricate your eyes.  Do not consider using a lubricant only if you have been diagnosed with a dry eye.  The same way you do not wait until your skin cracks before you use a moisturiser.  Do not use the lubricant once or twice a day, it is not enough. Do use a preservative-free lubricant, I recommend Optive Fusion.  For people with a positive dry eye diagnosis, they must follow the full program.
  2. If at all possible, do not have a fan or aircon blowing directly on your face.  This applies in the car too.
  3. Use a warm compress.  This discourages the meibomian glands from getting blocked up-they secrete the oily/fatty part of your tear film which prevents early evaporation.  (Dry eyes are mostly from a tear film that evaporates too quickly, and rarely a lack of tears-so the use of the word “dry” is not that accurate).  There are many ways to do this, one way is to heat a wetted cotton pad for 5 sec. in the microwave, and apply gentle pressure on your closed eyelids for 30 sec.  The pad must not burn, nor must it cool down at the 10 sec mark.  And no contact lenses to be worn while doing this.
  4. Apply the 20/20 rule.  After every 20 minutes of screen work, get up and take a 20 second break.  Do something physical in this 20 second period that is within your physical capabilities.  The increase in circulation, as well as the break in eye contact & eye focus, will benefit you more if done three times an hour than if you took longer breaks less often. 
  5. Ergonomics: Try and position your screen so that you have a slightly downward gaze, as a screen that is positioned too high will hurt your neck as well as make some types of spectacle lenses ineffective.  Likewise check the screen distance, chair quality and height etc. 
  6. Try as much as possible to reduce or eliminate screen exposure 2 hours before bedtime.
  7. Hydrate adequately.
  8. Any form of physical activity that is within your means & capabilities can only benefit you.
  9. On your doctor’s advice, some exposure to sunlight for Vit. D is worth considering, especially for children.

Are Your Screens Making You Blue?

All modern screens emit blue light.  The blue part of the visible light spectrum has the highest energy (as opposed to the warmer red side which has the least).  Why is this important?  During daylight, our brain produces a chemical called Serotonin which is partly due to the presence of blue light.  This gives us energy, increases our levels of alertness and affects our mood. At night Serotonin production stops and in its place we produce Melatonin, which calms us and helps us sleep. If this balance is lost, it affects our mood and causes sleep deprivation-think seasonal affective disorder and jet lag as some examples.

We are all using screens a lot more during the Covid pandemic, either because we work from home which inevitably results in longer working hours, due to home schooling, online meetings and workshops or to pass the time with online games and movies.  And the later we keep these screens on, the more we suffer from this chemical imbalance between Serotonin & Melatonin. The result is sleep deprivation, tiredness, lack of concentration and stress.  I believe that many cases of ADD & ADHD are either misdiagnosed or their symptoms are exacerbated  because of this. I also believe that sleep deprivation is a serious thing which affects a whole host of maladies like headaches, weight gain and hypertension.

To try and normalise things, take a 20 minute break every 20 minutes (it’s easy to remember the 20/20 rule); check your posture and hydration levels; get 20 minutes of sunlight exposure a day, and if you can’t avoid long hours in front of your screen, get a blue blocker coating on your lenses.  This blocks out the most harmful of the blue rays from entering your eyes and can be added to any prescription lenses.  If you don’t wear specs, we have ready-made non-prescription specs with the blue blocker added in stock.

Masks during the COVID pandemic – Just another opinion.

Paul Moldovanos Optometry

Due to the staggering amount of misinformation during the Covid-19, I will post this as nothing else but my personal opinion.  I hope to help clear up a lot of the confusion surrounding the use of masks for the benefit of all who visit our practice during this time.

There is a conflict of opinion whether masks are helping to slow the spread of the Corona virus or not.  I believe that a lot of the negatives were borne out of initial non availability of masks, and so a rationalisation-if we cannot get them, let us believe that we do not need them.  Other factors were probably not against the masks but their implementation. 

I do believe that they work and a recent study from Hong Kong shows a near perfect correlation between early masking and timeous flattening of the curve as opposed to countries who delayed their reaction.  Asian countries have for many years used masks in public to control the spread of germs due to their densely populated cities and higher number of outbreaks of new strains of flu.  So, this is nothing new.

Back to the negatives.  I do believe that if we use non-disposable masks, they must be washed daily and allowed to dry in full sunlight. Our noses should not stick out the top as this defeats the object, and we must be conscious of how clean our hands are when handling our masks. 

Ortho-K. Orthokeratology Demystified, By Paul Moldovanos Optometrists


Orthokeratology or Ortho-K has been around for over 20 years, yet many people are still unsure what it is exactly.

WHAT it does: A specially designed rigid contact lens gently reshapes the front part of the eye (the cornea), while you sleep.  When you wake up you will see clearly for the whole day, without your glasses.

WHY we do it: Ortho-K has many purposes. Some people don’t like wearing specs, yet contact lenses aren’t suitable either, because of their occupation (e.g. ideal for professional divers & where smoke can be a problem with fire-fighters wearing contact lenses), or a dry eye prevents all day comfort with their lenses. People who swim prefer Ortho-K over contact lenses.  Cosmetic factors are also a good reason to consider Ortho-K.  Ortho-K is also indicated in MYOPIA CONTROL, where young people’s myopia (short-sightedness) is changing rapidly.  Ortho-K slows down the change in myopia better than any other method.  In this way when they have stopped growing, their spectacle Rx will not be high at all.

HOW is it done: Modern methods don’t even require an initial fitting.  Data from a corneal topography reading is imported into an Ortho-K design software program. The lenses are designed & ordered, and you should have all day clear vision from 5 days after receiving the lenses.  The process is simple, relatively quick and totally painless.  My youngest Ortho-K patient was 9 yrs old when he got his 1st pair of Ortho-K lenses.

SUITBALITY: Although we can fit more eyes than in the past (we can even do a bifocal Ortho-K), not everyone is suitable for this procedure, so it’s best to first get a topography done to assess the suitability.

What is Myopia?

Myopia What is it?
What is Myopia?

Are your children short-sighted?
> > >The modern epidemic of Myopia.

Myopia, near-sightedness or short-sightedness, is characterised by blurred vision at far, and is normally caused by a longer than normal eyeball. This increase in length is very small, in thousands of millimetres or microns.

The eyeball normally grows in length as a child grows taller, and especially during puberty. But if it grows too long, then the eye cannot focus at the far distance.

There have always been myopic people, so why is it a problem now? Because of extended time spent at the near distance (since computers arrived), the eye has to work harder in order to maintain focus at near. This costs energy, so as an adaptation, the eye becomes more myopic so that it can now focus at near in a more economical way.  But with increased myopia, the eye is at greater risk for diseases later in the long term.
[Research shows that every 1.00D increase in myopia increases lifetime risk of maculopathy by 67%. There is also a greater risk of cataract & retinal detachment].

It is estimated that half the world’s population will be myopic by 2050.

And it’s not environmental factors alone; if one parent is myopic then the child is six times more likely to also be myopic. If both parents are, then the probability jumps to twelve times more likely.

Fortunately we have the means to manage the myopia. Myopia management can significantly slow down the progression of myopia during puberty, and in many cases stops it altogether. These methods are all safe and have other benefits too.

The success of any myopia management program depends on parents making sure their children are tested once a year regardless if they are myopic or not. And school screenings aren’t enough, they need a thorough exam at the optometrist’s rooms.

There are guidelines for screen & sunlight exposure which will be covered in the next article, as well as special contact lenses that are worn overnight (Ortho-K), which all yield excellent results.

Look out for the next article titled Myopia Management-The How.

Myopia Management Part 2 – THE HOW

Optometrist Paul Moldovanos, Myopia
Myopia Control Article by Paul Moldovanos Optometrist

As promised:


In the first article which introduces Myopia Management (also called Myopia Control), we discussed what myopia is and why the need to manage or control it.  In that article, an increase in myopia or short-sightedness, was equated to an increase in the length of the eyeball from front to back. It makes sense therefore, that controlling this deterioration must involve slowing down (or stopping) the eye from growing longer.
And that’s exactly what we do. We don’t stop it in an active or forceful way, rather we take away the reasons for it to want to grow longer.

Going back to the first article again, you will read that if we focus at near for too long, the eye uses a lot of energy, and so by becoming more myopic (by making the eye grow longer), allows the eye to focus at near without using as much energy.

Research has shown that of all the methods available to manage myopia, Orthokeratology overnight lenses (Ortho-K), is the most effective by a significant margin. Ortho-K involves wearing a special contact lens that is custom designed & manufactured for each individual eye, while you sleep. The lens exerts a gentle pressure which moulds the eye into a particular shape that does two things: in the medium to long term, it significantly slows down the progression of myopia by slowing down the rate by which the eye grows. And in the short term it corrects the myopia so that the wearer can see clearly all day without having to wear specs or contact lenses.  A safe alternative to LASIK.

For more information on Ortho-K, see our website

There are also ways to reduce eye-strain, like taking regular breaks, switching screens off 2 hours before bedtime and many more. These are are discussed during a normal eye exam appointment, and apply to adults & young people alike.

Eye Test Charts

EYE CHART, Optometrist, Paul Moldovanos Optometrist


Traditional eye charts were designed to test our vision in such a way that we had a standard or benchmark. In this way we could compare our findings with each other.

The way this was done was to have letters drawn on a chart, going from large to small size. Each line had a specific size or height, and they were read at a fixed distance.

At first the measurement was expressed in inches-that’s where 20/20 vision comes from; and the metric equivalent is 6/6. This means that the patient sees an object at 6 metres what a person with normal vision will see at 6 metres.

So if you have a visual acuity of 6/12, it means that you will see an object at 6m what a person with normal vision will see at 12m. Therefore 6/12 vision is half that of 6/6.

In 🇿🇦 South Africa, one needs a minimum visual acuity of 6/12 in each eye with or without spectacles in order to qualify for a driver’s licence, or if the one eye sees less than 6/2, then the other must have a visual acuity of at least 6/9.

We use an electronic chart (which comes complete with a gecko), that is calibrated to work at a distance smaller than 6m. The chart has multiple screens to prevent memorisation, but more importantly it is linked to the testing equipment that allows for a smoother and easier eye exam. It has built in numbers, pictures and symbols for the unlettered, and many other tests that check on the teamwork (called binocularity) of the eyes. A smoother, and sometimes slightly faster exam results in less subjective errors due to fatigue. 

#testchart #optometristsblog