Secrets in the war to stop shortsightedness from increasing

Trying to stop myopia progression is like deciding to go on a diet. Seriously. I'll get to that eventually but before we get too philosophical, let's take a step back.

Currently, more than 50% of twelve year olds in Singapore need to wear glasses because of myopia. And by the time the boys enter the army at 18 years of age, it will have increased to 80%. Unfortunately, myopia is a problem that continues to worsen as children grow up, usually stabilizing by the late teenage years. By this time, it is not uncommon to see patients with myopia of -6D and above. High myopia of course, can give rise to other problems such as an increased risk of retinal detachments and an earlier onset of cataracts.

Myopia or shortsightedness arises because of an imbalance between the focusing power of the cornea and lens of the eye, versus the length of the eyeball. In the type of myopia that arises in children, it is mainly a problem of the eyeball growing too long, ie axial myopia.

For many decades now, research has been ongoing both to find a cause of this abnormal eyeball growth, as well as to find ways to stop it or at least to slow it down. Because the actual cause and mechanism are not known, methods that have been tried are all based on theories or empirical data. Let's take a look at the things that have been tried.

Things that have been tried and failed

1. Timolol eyedrops to lower eye pressure.
Since eye pressure may potentially stretch an eyeball and make it bigger and longer, people tried to see if lowering the eye pressure could stop the eyeball from enlarging. Unfortunately Timolol eyedrops did not work. However, it remains to be seen whether more powerful pressure lowering medications like bimatoprost may have an effect.

Things that may work (either the evidence or effect is weak)
1. Glasses which reduce peripheral hyperopic defocus (Myovision by Zeiss)
These glasses appeared to have an effect in younger children who had myopic parents. Why it would only work in this subgroup of people is unknown but could reflect a weak effect or a chance finding.
Sankaridurg P, Donovan L, Varnas S, et al. Spectacle lenses designed to reduce progression of myopia: 12-month results. Optom Vis Sci 2010; 87: 631–41. 

2. Rigid gas permeable (RGP, or semi hard) contact lenses
At the age of about 11 I was introduced to 'hard' or RGP contact lenses in the hope that it could slow down the rate of increase of my myopia. In fact in my case, it wasn't that successful in this regard. A well conducted trial showed that RGP lenses do not slow down the growth of the eyeball, but may have an effect by reducing the steepening of the cornea.# This may be only a temporary effect from the pressure of the lens on the eyeball.
#Walline et al. A randomized trial of the effects of rigid contact lenses on myopia progression. Arch Ophthalmol. 2004 Dec;122(12):1760-6.

3.Orthokeratology
Orthokeratology (OK or Corneal Refractive Therapy/CRT) takes the concept of corneal flattening using pressure from a lens one step further. In this method, RGP lenses of a special shape are worn to sleep. The lenses press on the patient's cornea during sleep, so that during the day the lens can be removed, and the cornea retains the ideal shape which corrects the long/shortsightedness and astigmatism. After a few days of not wearing the lens to sleep, this effect is lost, so the power lowering effect is temporary.

But does it stop myopia from increasing?

Walline JJ, Jones LA, Sinnott LT. Corneal reshaping and myopia progression. Br J Ophthalmol. 2009 Sep;93(9):1181-5.

The above study showed that yes, it seemed that orthokeratology can slow down the growth of the eyeball compared with soft contact lenses. This effect is not as strong as 1% atropine eyedrops (0.25mm elongation with OK versus -0.02+/-0.35 mm with atropine at 2 years).

In other words, OK lenses had an effect somewhere between soft contact lenses and 1% atropine, but without the side effects of the atropine. Do consider though, that wearing contact lenses to sleep is generally felt to increase the risk of eye infections.

Things that work (with strong evidence and strong effect)

1. Atropine
The idea of using atropine came about because of its well known ability to relax the ciliary muscles in the eye (which are used for near focusing). Since as the theory goes, too much near work is related to shortsightedness, and near work results in prolonged contraction of this muscle, would relaxing the muscle have an effect on myopia progression? The results of well conducted studies show that yes, indeed atropine has a powerful effect on slowing or stopping the worsening of myopia.

There are two concentrations in common usage: 1% (stronger) and 0.01% (weaker). The 1% concentration is very effective but has side effects of causing sensitivity to bright lights and temporary inability to focus for near. These are reduced by using special progressive glasses that turn dark in bright light. With the 0.01% concentration, there are no side effects but the effects of slowing down myopia are not as pronounced. Which specific medicine is used depends on the degree of shortsightedness, how fast it is progressing and the child's tolerance to the side effects of the stronger concentration. Read more about this at my other post on atropine and myopia.

2. Outdoor time
2 generations ago, it was much less common to see a shortsighted person in Singapore, despite people having essentially the same set of genes. Other things have changed, notably our environment and activities.

Increasingly, evidence points to the importance of outdoor activities in reducing the rates of myopia and its progression.# What is it about being outdoors that slows myopia? Many people think it is because we get to see things far away when we step outdoors, but this effect of distance versus near visual work has been shown to be only a weak one.*
#Rose KA, Morgan IG, Ip J, et al. Outdoor activity reduces the prevalence of myopia in children. Ophthalmology 2008; 115: 1279–85.
*Mutti DO, Mitchell GL, Moeschberger ML, Jones LA, Zadnik K. Parental myopia, near work, school achievement, and children’s refractive error. Invest Ophthalmol Vis Sci 2002; 43: 3633–40.

In fact, it is likely to be due to the difference in amount of light being seen by the eye, when comparing being indoors versus outdoors.

When we step outdoors, even at 5 or 6pm in the evening, we are typically being exposed to much more light than we get even with the brightest lamps indoors. It has been shown that bright light leads to the release of more retinal dopamine, a chemical which may play a role in controlling eye growth. It is intriguing that using a chemical to block dopamine in animals can also block the protective effect of bright light.#
#Ashby RS, Schaeff el F. The eff ect of bright light on lens compensation in chicks. Invest Ophthalmol Vis Sci 2010; 51: 5247–53.

SO.....
It is said that in losing weight, '..., you must accept that this is your new lifestyle of eating healthy and being physically active...' http://www.webmd.com/diet/features/10-diet-secrets-lasting-weight-loss-success

And equally, in trying to control myopia, the patient must accept a new lifestyle of regular outdoor activity (in sunlight) and being more active. At least 1-2 hours everyday. As a follow on from that, it's also important to ensure that when indoors/doing near work, that the child has a brightly illuminated environment. It does not matter what type of light it is (eg sunlight by the window, fluorescent, LED etc), as long as it is bright. Failing which, the most effective treatment so far is atropine eyedrops.

No, wait..... Actually it's easier to control myopia than to go on diet. If only our waistlines would stabilise after a certain age (like myopia), so that we don't have to worry about it any more after that!

References:
Lancet 2012; 379: 1739–48
Ophthalmology 2002;109:415–427

Atropine eyedrops for the control of shortsightedness

Shortsightedness is a huge problem in Singapore and many big cities around the world. More than half of Singapore schoolchildren are already wearing glasses for shortsightedness by the age of 12 years. What is worrying is that the earlier one starts out becoming shortsighted, the higher the final spectacle degree tends to be. Very highly shortsighted people are at increased risk of eye problems like cataract and retinal problems at a younger than average age.

It is important therefore that we try to slow down the increase of shortsightedness as much as possible. Ensure that a child spends 1-2 hours outdoors in sunlight each day. Take regular breaks from near work when reading or with computer use. Apart from these, using Atropine eyedrops is the only method proven in big studies (randomised controlled trials) to slow down the rate at which shortsightedness increases.

What is Atropine?

This is a chemical obtained from plants in the same family as the nightshade plant. Owing to the presence of extremely high levels of atropine and other chemicals, the berries and leaves of the plant are poisonous. 

Interestingly, the nightshade plant is also called ‘belladonna’ (meaning beautiful woman in Italian) as people in the past used atropine to dilate the eyes for a cosmetic effect! It achieves its effects in the body by blocking a special receptor molecule that among other things controls the action of muscles as well as the growth of the eyeball.

Atropine is available in many forms, but for eye conditions it is used as an eyedrop. Various concentrations have been tried but the commonly available concentrations are 1%, 0.125% and 0.01%.

Traditional treatment (Atropine 1%)

Traditionally, to reduce the rate at which shortsightedness increases, 1% Atropine eyedrops were used once a day or even once a week. In a study at the Singapore National Eye Centre, 1% eyedrops used once a day reduced the progression of shortsightedness from an average of 100 degrees a year to less than 25 degrees a year. Our experience suggests that using it even once a week has a very similar effect.

Side effects of traditional Atropine treatment

Atropine 1% dilates the pupil and relaxes the muscle used for near focusing inside the eye. As a result patients feel very sensitive to bright lights and with normal glasses on have difficulty with close up work such as reading. If this concentration is used, special glasses which turn dark outdoors (‘Transitions’ lenses) and which have progressive lenses (having a near section below for near focus) are required. All of these side effects are temporary and disappear when the patient stops using the drops.

Newer treatments (Atropine 0.125% and 0.01%)

In an effort to do away with the side effects of Atropine, lower concentrations of Atropine were tried. When used once every day, 61% of those using 0.1% and only 6% of those using 0.01% Atropine felt a need for special ‘Transitions’ and progressive lenses. Therefore, normal glasses or contact lenses can usually be worn while the 0.01% Atropine concentration is used.

However, the lower concentrations are not as effective as the 1% concentration at slowing progression of shortsightedness. On average, the myopia progression over 2 years for 1% Atropine was 28 degrees, for 0.1% 38 degrees, and for 0.01% 49 degrees. This was still better than the 120 degree increase seen in those who were not using the Atropine eyedrops.

General pointers about using Atropine for shortsightedness

Whether 1% or 0.01% Atropine is used, the eyedrops must be used for a long period of time. Although the shortsightedness increases at a slower rate while Atropine is used, the rate increases again when it is stopped. The idea is therefore to use the Atropine during the period of time when the shortsightedness is increasing fastest. Usually by about 18 years of age, the rate of increase of shortsightedness would have already slowed down naturally.

This means that on average, most children who use the eyedrops would be using them for several years. The longer the eyedrop is used, the bigger its potential effect. For example, if a child had shortsightedness that was increasing by 100 degrees every year, using the 1% eyedrop for 3 years would reduce the final power by 300 degrees. This might mean that instead of having 500 degrees of shortsightedness as an adult, he/she would only have 200 degrees of shortsightedness finally.

In trying to slow the progression of shortsightedness, a number of decisions have to be made. Should Atropine be used or not? Should the 1%, 0.125% or 0.01% concentration be used? How long should the child continue with the eyedrops?

These decisions should be made after a discussion of the pros and cons of each decision with your eye doctor. For example, if the shortsightedness is increasing very fast and is already of a high degree, one would favour using the 1% eyedrop despite the side effects. On the other hand, if the side effects cannot be tolerated and one is willing to give up some of the stabilizing effect of the 1% eyedrop, then the 0.01% concentration is a good option.

EDIT 7 MAY 2018
Please note that I do not run an online pharmacy, and these are illegal in many parts of the world. Do not request Atropine from myself, or any other doctor, unless you or your child have seen the particular doctor and it has been determined after a proper consultation that Atropine is necessary. Requests for Atropine will be deleted in the future to avoid cluttering up the comments section in this post.

P/S.
Have you ever seen pinhole glasses? I heard that they are available at Watsons. Do NOT waste your money on these gimmicks. They do nothing to help the eyes or vision. Have a look at this link: Case Watch report on settlement of charges of misleading claims