Short-sightedness: better vision thanks to drops, lenses & special glasses

It is becoming almost endemic: myopia, better known as short-sightedness. More and more people are suffering from not being able to see well in the distance - although the term "distance" becomes obsolete as the number of dioptres increases. This is because people who are really short-sighted (from around -6 dioptres) can no longer see clearly at a distance of 30 to 40 centimetres.

According to the International Myopia Institute, 30 per cent of people worldwide are currently short-sighted - and the trend is rising exponentially. The institute assumes that this figure will rise to half of the world's population by 2050.

In China, there are already reports of up to 95 per cent of people affected in certain social classes. The figures are also high in Switzerland, where 33 per cent of adults are affected by myopia, as the statistics show.

Myopia is being diagnosed more and more frequently, especially in children. No wonder, as this visual defect first appears at primary school age and then causes problems. Classic "school myopia" usually begins at the age of eight and usually progresses until around the age of 15.

I spoke to Marc Fankhauser, optometrist and contact lens specialist at the optician's studio Eyeness in Bern, about treatment options for myopia - and took a look at the research to understand the explosive rise in short-sightedness.

Myopia: genetics or environmental influences?

Myopia is the most common developmental anomaly of the eyes. And it is initially genetic, i.e. hereditary: in myopia, the eyeball is longer than usual, which is why light does not refract at the retina but in front of it.

However, it is not only poor distance vision that characterises defective vision: "In the presence of myopia, the risk of degenerative eye diseases, such as cataracts (cataracts), glaucoma (glaucoma), retinal detachment or myopic macular degeneration, increases with age," writes the Austrian Ophthalmological Society in a release.

The World Health Organisation (WHO) even describes uncorrected defective vision as the second most common cause of visual impairment and vision loss.

The dreaded retinal detachment can already affect people with myopia between -1 and -3 dioptres: they have a four times higher risk of retinal detachment than people with normal vision.

With higher dioptres, the risk is even ten times higher. As the eyeball grows longer than it should with myopia, more and more tensile force is exerted on the sensitive eye membranes. This can cause the retina to tear, develop holes or detach completely from the choroid.

The good news is that you can take preventative measures to prevent your children from developing this condition, as certain environmental influences are more important than genes. This is emphasised by a study in the Community Eye Health Journal. The researchers write: "The development of myopia is multifactorial, although the influence of genes can be categorised as small."

Shortsightedness in children: More time outside, less in front of the screen

More important are external factors, specifically daylight, and avoiding close work - i.e. short reading distances. In 2015, the specialist journal Nature reported a considerable increase in cases of myopia in South East Asia: since the Second World War, short-sightedness has risen from 20 to 80 per cent. The authors conclude that the visual system has a remarkable ability to adapt from distance to near vision: according to the researchers, the reasons for this could not be purely genetic.

On the contrary: working in too little or artificial light is considered by researchers to be the main reason for the explosive increase in short-sightedness. The Covid-19 pandemic gave rise to new research. Home schooling and lockdowns have significantly increased children's screen time, while time spent outdoors has been limited. The result is shown in a comparative literature analysis in the Cureus Journal of Medical Science: Little time in the fresh air and a lot of time in front of a screen during the pandemic years had a significant impact on the myopia trajectories of the children studied.

In particular, the influence of natural versus artificial light is likely to play a role: Although the exact influences of daylight on myopia have not yet been well researched, a study in the Sage Journals suggests a link between myopia and dopamine and vitamin D levels.

Myopia correlates very specifically - even for adults - with the amount of time spent in front of screens or reading books. A paper from the University Eye Hospital Tübingen shows the result: myopia correlates with the duration of education (and therefore the level of education). It states: "On average, you become 0.27 dioptres more short-sighted per year of education - almost one dioptre in 3 years."

Treating and preventing short-sightedness

For a long time, short-sightedness was defined by the number of dioptres. Optometrist Fankhauser is also aware of this and explains: "However, the length of the eye is decisive. The aim of treatment should therefore be to prevent the eye from becoming any longer." The wrong treatment, on the other hand, can actually stimulate the growth of the eyeball, says Fankhauser. In research, this effect has been observed with undercorrection with single vision lenses.

Modern myopia management therefore focuses on the axial length of the eyeball, which can be measured using special devices - and should also be measured regularly. Axial length biometry is part of "longer-term success monitoring", writes Dr Michael Bärtschi, owner of Eyeness, in this overview paper.

As myopia first appears at primary school age, scientists agree that slowing down the progression of myopia at an early age should be a top priority for health policy. The growth of the eyeball is completed at around 15 to 17 years of age - the measures listed below therefore apply to children and young adults.

Important to know: There is no gold standard in the treatment of myopia. "It would be nice if it were that simple," says expert Fankhauser. "It depends on the wishes of the child and the parents. Some are open to contact lenses, others prefer to wear glasses, others take the medication, i.e. the atropine drops. Ultimately, you have to do something about the growth of the eye. It's bad to do nothing at all."

1. daylight as a therapy for short-sightedness

Studies show: Spending time outdoors every day is crucial to preventing short-sightedness or slowing its progression. A study involving 952 Chinese schoolchildren came to the conclusion that 40 minutes of outdoor exercise during school was able to curb myopia progression not only acutely, but over the next three years.

In children aged between 5.5 and 8.5 years, the positive effect of daylight on the length growth of the eyeball is apparently greater than in younger children.

As a study from Taiwan showed, it protects children from myopia if they play outside for 11 hours a week. This is also the common recommendation today: children should spend one and a half to two hours outdoors every day.

While spending a lot of time outdoors is favourable, close work and short reading distances are unfavourable in terms of myopia reduction. Although there is a lack of "reliable data on screen time or distance used for large cohorts", according to the recommendations of the Professional Association of Ophthalmologists in Germany from June 2022, these two factors could nevertheless be a particular driver of pre-existing myopia. The following recommendation therefore applies: "Reading times of more than 30 minutes at a reading distance of less than 30 cm should be interrupted by 10 minutes of looking into the distance."

As an alternative, the 20-20-20 rule is also advisable to get the eyes to focus more on the distance and away from the near focus: focus on something 20 feet (approx. 6 metres) away for 20 seconds every 20 minutes. In any case, there should be at least a cubit's length between your eyes and the reading object when reading or working on a screen.

2. atropine eye drops for myopia

Eye drops can have a similar effect on the progression of myopia in children. Atropine is actually a neurotoxin extracted from the belladonna plant. In very small doses, the active ingredient is used in a variety of medical applications - for example to dilate the pupils or to treat short-sightedness. As early as 1874, the Breslau ophthalmologist Hermann Cohn suggested the substance as a treatment for short-sightedness. However, atropine is still an off-label therapy for those affected, i.e. health insurance companies do not reimburse the costs, as the drug has not yet been approved as a myopia therapy by the Swiss Medicines Agency.

In a study by the German Ophthalmological Society, atropine eye drops work even better for short-sightedness than other measures such as contact lenses or reduced screen time.

However, there are side effects such as sensitivity to glare and paralysis of accommodation (near vision) - and rebound effects have also been observed, meaning that myopia progresses even faster after the drops are discontinued. What's more, most of the studies on the effects and side effects were conducted in Asia.

A study in Tokyo showed that an atropine concentration of 0.05 per cent (as recommended for Asian children) can be classified as clinically critical in Caucasian children. An ongoing study from Germany is currently investigating the effect of low-dose atropine. The current standard here is a concentration of 0.025 to 0.01 per cent. Results of the study are still pending.

3. myopia management with contact lenses

Special soft contact lenses, either defocus or multifocal lenses, can also have a positive effect on myopia. On the one hand, they sharpen the image, enable good vision and at the same time slow down the length growth of the eyeball.

"Defocal and multifocal lenses basically do the same thing," says contact lens specialist Fankhauser. "They focus the centre of the retina and also take care of the periphery so that there is no overcorrection." According to researchers at Ohio State University, soft multifocal contact lenses are particularly effective.

According to Fankhauser, there are also Ortho-K night lenses for short-sighted people: "You insert these night lenses before going to bed and can then see well during the day even without contact lenses." They reshape the cornea of the eye in such a way that short-sightedness is compensated for during the day. However, this effect is only noticeable if the lenses are worn regularly and they generally only help with short-sightedness of up to -6 dioptres.

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4. D.I.M.S. lenses for myopic children

Conventional single vision lenses are still used today to treat short-sightedness. The problem: "Single vision lenses correct the retinal centre and thus produce a sharp image. But they don't stop the lengthening of the eye," says Fankhauser. In the worst case, with undercorrection, conventional lenses can even stimulate eye growth - and the number of dioptres increases steadily.

Rather new on the European market, however, are defocus lenses with D.I.M.S. technology. D.I.M.S. stands for Defocus Incorporated Multiple Segments. The lens is a special single vision lens that contains hundreds of small segments on its front surface. These are virtually invisible to the other person. For the short-sighted person, however, the lenses create a focal plane in the centre exactly on the retina, while in the outer periphery the focal plane is in front of the retina - in other words, a blur is deliberately created. This creates what is known as a "myopic defocus", which does not stimulate the eyeball to grow.

The first studies have been conducted on D.I.M.S lenses. However, there are still no long-term studies from Europe to prove their effectiveness in comparison to contact lenses and medication.

If a child is diagnosed with short-sightedness, parents and those affected should ideally consult specialists who specialise in myopia management. This is how optometrist Fankhauser treats his customers: "Once myopia has been diagnosed, we discuss the exact wishes of the parents and child, explain the options and then start the therapy. In six-month follow-up checks, we see whether the growth has been reduced. If not, we adjust accordingly and change the form of therapy or combine the measures, for example daily lenses with atropine drops or atropine and glasses with D.I.M.S lenses. However, studies confirming the effect of combination therapy are still lacking."

From the current study situation, it is therefore not possible to say conclusively which measure and combination is the best. "The most important thing for children with myopia is to spend a certain amount of time outside during the day with plenty of distance vision."