For decades doctors have used low concentration atropine eye drops to slow down progression of myopia (or near-sightedness) in children, but what if you could use those drops to prevent myopia from ever developing? A new study published in JAMA shows promising results!

The LAMP 2 study is an ongoing randomized, placebo-controlled, double-masked trial researching the effects of atropine on incidence and progression of myopia. In this new arm of the trial, 474 children between the ages of 4 and 9 who had no myopia at the time of the study were split into three different randomized treatment groups: placebo eye drops nightly (n=155), 0.01% atropine drops nightly (n=159), or 0.05% atropine drops nightly (n=160). At the time of enrollment, the children had a prescription between +1.00D and 0.00D and less than -1.00D of astigmatism. These children were followed over a 2 year time period with routine eye examinations to monitor any change to their prescription. 

At the end of 2 years, there was a statistically significant reduction in the incidence of myopia amongst children using low dose 0.05% atropine every night versus those using the placebo eye drop. 53% of the children using the placebo drop developed myopia; 45.9% of those using 0.01% atropine developed myopia, and only 28.4% of those using 0.05% atropine developed myopia at the end of 2 years. The incidence of myopia between 0.01% atropine users and the placebo group was not statistically significant. Axial length elongation also showed significantly lower progression in the 0.05% atropine group; 0.24 mm/year on average with 0.05% atropine versus 0.32 mm/year with 0.01% atropine and 0.35 mm/year with placebo. 

The side effects of low dose atropine were reported as very mild; in this study photophobia (or light sensitivity) was the most common reported side effect, with 12.9% of children using 0.05% atropine reporting this issue. Interestingly, 18.9% of participants using lower concentration 0.01% atropine and 12.2% of patient using placebo eye drops (which had no pupillary dilation side effect) also reported photophobia. 

The Take Home

Study authors concluded that "among children aged 4 to 9 years without myopia, nightly use of 0.05% atropine eyedrops compared with placebo resulted in a significantly lower incidence of myopia at 2 years." 

More research will continue to be reported from the ongoing LAMP 2 trial, and it will be interesting to see if this preventative effect with 0.05% atropine continues year after year. Based on this strong data, for parents who are concerned about their children being at high risk of developing myopia the use of 0.05% atropine as a preventative treatment before myopia develops is absolutely worth considering. The only FDA approved treatment options of myopia control, including MiSight soft multifocal contact lenses and orthokeratology lenses, require the child to already be myopic before starting treatment, so the incorporation of atropine as an option to use before myopia even begins is a novel new advancement for doctors in our goal to keep children's vision as clear as possible and reduce both dependence on glasses and contact lenses and the potential health risks associated with high levels of myopia. 

At the time of writing this article, only 2 treatments are FDA approved for myopia management and both are contact lenses. Myopia management is the process of slowing down the worsening of near-sightedness in children. Studies show that on average, children with myopia will worsen by -0.50D per year (and -0.75D per year for children of Asian descent) until they are done growing (around age 17 for most). This prescription worsening is associated with actual elongation of the eye ball, called axial length. Faster axial length growth (0.2 mm or more in childhood) is considered rapidly progressive and associated with the risk of much higher prescriptions and higher risks for associated eye diseases, including retinal detachment, glaucoma, and myopic maculopathy. You can read more about the FDA approved myopia management contact lens options here: MiSight soft multifocal contact lenses and Abiliti orthokeratology lenses. But not every parent (or child) is eager to start contact lens wear; are there approaches to slow down myopia progression with glasses? 

Bifocals and Progressive Addition Lenses (PALs)

Childhood myopia is caused by a complex combination of factors, including genetics, reduced outdoor time, and increased near work. When prescribing glasses for children, doctors measure not just what it takes to make distance vision clear, but also the strength of the focusing system of the eye. Children with reduced accommodation (ability to focus on near tasks like reading) or with convergence inefficiencies (eyes that can't comfortably maintain coordination of gaze when looking at near tasks) have increased strain on their eyes when performing near tasks, and theoretically could be at more risk of worsening myopia, but research shows it's much more complicated than this. 

With this theory of near strain being a potential factor in worsening myopia, several studies have investigated if there is any benefit to prescribing glasses with a near addition to reduce strain on the eyes with reading or close tasks through the use of bifocals or progressive glasses. A 2014 study of 135 children with at least -0.50D of myopia between the ages of 8 and 13 showed that those who wore +1.50 add executive bifocals experienced statistically significantly less myopia progression and axial elongation over a 3 year period than their peers who were prescribed normal single vision distance glasses. Average myopic progression over 3 years was -2.06D for the control group and -1.25 D for the bifocal group (a myopia control rate of 39.3%); average axial length progression over 3 year was 0.82 mm of the control group and 0.57 mm for the bifocal group (a myopia control rate of 30.4%). Note that these myopia control rates are less than those reported by the FDA approved contact lenses for myopia management (59% control of spherical prescription change), but still statistically significant.

Interestingly this study found that the myopia management rate was slightly more effective if the children who were prescribed bifocal glasses also had a lower lag of accommodation (more strain on their eye muscles at near) and were also prescribed 3 prism units of base in prism on eye eye. The prism cohort of children had a myopia progression rate of -1.01D over 3 years (a 51% myopia control rate) and 0.54 mm of axial length growth over 3 years (a myopia control rate of 34%). The study authors concluded that executive lined bifocals were effective for myopia management, and that prism lined bifocals were more effective if the child also had accommodative dysfunction. 

So we know executive lined bifocals have some effect, though less than the FDA approved contact lens options. But what if your child doesn't want a huge line going across the middle of their glasses? Would an invisible line bifocal (called a progressive addition lens or PAL) work as well?

The Hong Kong Progressive Lens Myopia Control study investigated just that: 153 myopic children between the ages of 7 and 10.5 were followed over a 2 year time frame. Half were prescribed progressive glasses with +1.50 D of near add, and the other half were in the control group, prescribed normal single vision distance glasses. Over the 2 year study period, the control group had an average -1.26 D increase in myopia and the progressive group had a -1.12 D increase (a modest 11.11% myopia control effect that was not statistically significant). Axial elongation was also measured and the control group had an average 0.63 mm increase in axial length after two years versus a 0.61 mm increase in the progressive group; again not statistically significant. 

The COMET (Correction of Myopia Evaluation Treatment) Study also explored the benefit of progressive lenses. This study followed 469 'ethnically diverse' patients with myopia (-1.25 to -4.50 D) between the ages of 6 and 11 for 5 years. The children were randomly assigned to either progressive addition lenses with +2.00D of add or single vision distance lenses. After 3 years, the average amount of myopia worsening was -1.48D in the control group and -1.28D in the progressive group, a modest but statistically significant myopia control effect of 13.5%. Axial length elongation was on average 0.75 mm in the control group and 0.64 mm in the progressive group, a modest but statistically significant 14.67% myopia control effect. 

The largest myopia management benefit was experienced in the first year, and as the study progressed the effect dwindled more and more. After 5 years, the average amount of increased myopia was -2.10D in the control group and -1.97D in those wearing progressives - not statistically significant. 

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Researchers concluded that even the small benefit seen early in the study was not significant enough to warrant a change in clinical management of myopic patients away from single vision glasses to progressive lenses.  

Myopia Management Glasses Are Coming to the US

While not yet available in the United States, glasses that are specifically approved for myopia management are coming and are already available in Canada, Europe, and Asia. Studies have shown these glasses work very effectively at reducing myopic progression both of prescription and axial length! Both of these technologies work by incorporating high plus power 360 degrees throughout the lens and maintaining clear central distance vision. With executive bifocal and progressive addition lenses, the high plus power is only being processed by the eye with inferior gaze and is thus more limited in it's ability to actually induce peripheral defocus (see this blog post for more insight into how peripheral defocus is essential to myopia control). 

Defocus Incorporated Multiple Segments (DIMS): This unique design found in Hoya's MiyoSmart myopia management lenses uses 400 individual peripheral lenslets of +3.50D scattered throughout the lens. A study published in 2020 followed 183 Chinese children between the ages of 8 and 13 with -1.00 to -5.00D of myopia. On average the control group wearing single vision glasses progressed -0.85 D in that time, and the DIMS group progressed -0.4 D, a 52% myopia control effect. There was also a 62% reduction in axial length progression in the DIMS group compared to control. 

Unlike the COMET study of progressive glasses outlined above where there was waning benefit, studies have shown that DIMS technology continues to achieve statistically significant results. In a 3 year follow-up study of 128 children, kids that had been wearing the DIMS lenses for the prior 2 years continued to do so, and kids that had been wearing single vision distance lenses now switched into DIMS. This study proved that the myopia control effect achieved in myopic prescription change and axial length was stable and maintained over time. Children that switched from control to DIMs group also achieved the same myopia management effect as children enrolled initially in the DIMs group in their first year. The repeatability and consistency of results has garnered a lot of attention that this technology has become our first truly effective glasses option for myopia management. 

Highly Aspheric Lenslet Target (HALT): This unique design is found in Essilor's Stellest myopia management lenses and uses 11 concentric rings of over 1000 lenslets with varying powers. 2 year study data was published in March 2022 following 157 Chinese children between the ages of 8 and 13 with -0.75D to -4.75D of myopia. On average the control group wearing single vision glasses progressed -1.04 D in that time, and the HALT group progressed -0.66D, a 55% myopia control effect. There was also a 51% reduction in axial length progression in the HALT group compared to control. Interestingly, kids who wore their HALT glasses more had an even better myopia management effect. Children who wore their HALT glasses 12 hours or more per day, every day achieved a 67% reduction in myopic progression and a 60% reduction in axial elongation. 

Stay tuned! While neither of these myopia management glasses solutions are available in the United States now, they should be coming soon!

If you are just joining us in our conversation of current working theories for why myopia (near-sightedness) is becoming so much more prevalent in modern society (an increase of 66% since the 1970s!) then check out our previous articles on peripheral defocus theory and near point stress theory.  Remember all of these theories are not meant to stand alone -- our eyes develop over many years into adulthood, and in addition to genetics there are definitely strong environmental factors at play in determining the prescription we end up with.  Today we're discussing some really intriguing research that is surprisingly simple; how can light change how our eyes develop?

The average US classroom is a dim place -- set around 500 lux on average, but recommended light settings can be around 300 lux for activities like computer and projector use. image via

A glass classroom in Yangxi City, China via

We've all seen the startling numbers -- society as a whole is getting more and more myopic with each generation at a speed that can't be explained by genetics alone.  About 1/3 of the US population is near sighted, an increase of 66% since the 1970s, and in Asia the number of school children that are near sighted may be as high as 90%.  But with the World Health Organization now discussing a true myopia epidemic, scientists and researchers are struggling to understand in a very short time why our vision as a population is changing so rapidly.  The real truth is that we can only theorize what is causing our eyes to change -- studies on chicks and monkeys about how the eyes develop in different environments give us some insight, but to understand the human eye we often have to rely on correlational study data that can prove cause, only relationships.  The result is a number of theories for why myopia occurs and progresses:

Nearpoint Stress Model

Kids are drawn to visual stimuli like lights and colors, and they tend to like to get very close!  With the near point stress model of optometry, too much time or strain on the eyes this close may eventually result in us becoming myopic!  It gives credence to listening to mom and dad about not sitting so close to that TV. via

The most studied and discussed theory behind why children develop myopia is that it is a result of visual stress from near work.  Our eyes are evolutionarily made to excel at distance vision.  Images from about 20 feet away would have perfect resolution to details as small as 8.87 mm in size in a "perfect" or normal eye.  But today's world finds us even as very young children spending less time looking across the horizon, and more time looking at objects much closer.  Think about a book, cell phone, tablet, computer, television.  All of these items are much closer than what our eyes are theoretically best designed to see.   In order to see things clearly up close, our eyes use the focusing system (which includes the eye muscles and the lens inside the eye, also called accommodation) to bring focus closer in.   Our eyes are designed to be able to change this focus back and forth between distance and near until we age to the point that the system no longer works -- this is called presbyopia and it's why people can't see as well to read after age 40.  But in a young child, the focusing system is flexible and should be able to transition back and forth to see both up close and far away.  The near point stress model of myopia theorizes that if too much time is spent up close, or if for some reason up close work is more difficult than it should be, the eye will begin to change to reduce the amount of stress it has to overcome to focus clearly at near.  When the eyes design themselves for easier, clearer reading vision that means they no longer focus light clearly far away -- this is myopia.

Here's the body chemistry behind the model: our body responds to stress by activating the sympathetic nervous system.  You'll often hear this referred to as fight or flight.  When our body is stressed by environment or emotion or fatigue, or just about anything difficult or stressful, the sympathetic nervous system takes over.  This is the system that increases our heart rate, speeds up breathing, slows down digestion, and makes us more alert.  With the eyes, an activation of the sympathetic nervous system means that your pupils dilate so that you can take in more light and be more aware of your surroundings.  In order for your pupil to dilate, your ciliary muscle (the muscle around the iris that also controls our focusing system!) relaxes. As a side effect of this muscle relaxation, your focusing system relaxes.  Your body has entered an alert mode that was meant to help it see threats from far away --but that means you've just diminished the action of those eye muscles that let you focus on things up close.  So the theory here is that when you get stressed (you are learning to read and it's a hard word, you've been reading too long, you're tired), your body enters sympathetic/fight or flight stress mode and your body now makes it even harder for you to see what you are reading!  The result of all this stress? Your body has two choices: Fight (which can lead to common binocular vision issues like convergence disorders, accommodative spasm, and ultimately even the prescription changes that result in myopia) or Flight (which is what some children do -- they avoid reading, and may even get incorrectly diagnosed with ADD).

Need a refresher?  Accommodation is what each eye does to bring the image into focus clearly on the retina.  Convergence is the movement of the eyes together to point both eyes at the right place in space for clear focus on the image.  These two systems work in conjunction to keep vision clear and single. via

Let's say your body decides to fight -- what's going on in the eyes when they are fighting to stay focused up close?  When we are trying to focus on a near image but our accommodative system isn't able to handle the work to bring the image into focus, our eyes turn to the convergence system. Convergence is the system that brings the eyes together to focus on the same point in space.  When we look at something up close, our eye muscles turn in (convergence), and shift focus closer to the object (accommodation).  If you don't have enough accommodation to see clearly, then you draw more effort from the convergence system.  If you are over-converging to make up for insufficient accommodation, then your eyes have what's called an esophoric posture.  The problem? If you are overfocusing on a target, that means your eyes are much more likely to see double since they aren't positioned equally to where you are looking.  How do the eyes try to prevent from seeing double? They try to pull in more accommodation.  This back and forth balance between accommodation and convergence as they work to keep vision clear and single is called the AC/A ratio and one of the foundations of binocular vision system performance.  The theory of near point stress implies that accommodation and convergence are constantly out of balance in the patient at risk, and the eye adjusts its shape in order to relieve some of this constant pull and tug by becoming myopic.  Image can't focus clearly on the retina?  Well let's make that eyeball longer so that when I look up close the image falls on the retina without any effort from this beat up focusing system.  But if lengthening the eye is the body's way to solve the problem, why does the myopia keep getting worse?  The reason is that the balance of accommodation and convergence is still messed up, so the eye has to keep lengthening to keep things in check.

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In this theory, vision therapy may play a role in myopia control.  If we can find early children at risk -- children that have accommodation or vergence issues that are just starting to express themselves, then we can help the child develop their focusing system skills to handle the amount of near work required to get through the day at school and home.  If your doctor has talked to you about your child needing vision therapy or reading glasses or both, they may have mentioned something to the extent of "wearing glasses now may help keep them from needing glasses later."  If so, they are citing this near point stress concept of myopia progression.

Theoretically if nearpoint stress was the sole cause of myopia development, then wouldn't wearing bifocals that reduce the accommodative demand for near work prevent myopia progression?  Unfortunately this doesn't hold true in clinical research. Studies where children were prescribed single vision glasses compared to children prescribed progressive glasses (with a reading power in the bottom to reduce near accommodative demand) report no clinically significant reduction in how quickly myopia progressed.  Undercorrecting myopia has also been disproven as a possible means to slow myopia creep.  In fact, undercorrecting a child has been shown to make myopia progress faster than fully correcting the child's prescription! So if near point stress isn't the whole story, what else is causing myopia to develop in our children?  In our next post we talk the other two theories of myopia development: sunlight exposure and peripheral defocus theory.

A new longitudinal study out of Bristol University continues to support other recent correlational data that time outdoors playing seems to be related to a decreased risk for poor distance vision.  Near-sightedness or myopia is a refractive condition where the person sees well up close, but very poorly in the distance.  Click here for more details.  In the past, data has supported that more time reading as a child is associated with myopia, but in this new study, time indoors (not specifically reading) also appears to have a link.

Colleague Dr. Joy Ellenberger and a young patient Photo Via Smith Eye Care

14,000 children were followed from age 8 to 9 until age 15 during Avon Longitudinal Study.  Children were grouped into 2 categories based on survey information provided by their parents:
High Time Outdoors = 3 or more hours in summer, 1 or more in winter
Low Time Outdoors = anything less
Those children spending "high time" outdoors were much more likely to have normal vision.

In the past, myopia development has been theoretically linked to near strain, like long hours reading.  New research however is showing that bright light may be essential in the developing eye.  Bright outdoor light stimulates the release of dopamine, a neurotransmitter, in the brain.  Research on baby chicks has shown that higher levels of dopamine in the brain and retinal cells is correlated with less risk of myopia.

Other research out of the University of Alabama at Birmingham (also home to an optometry school!) has shown that bright light exposure in tree shrews appears to minimize the risk for myopia.  Researchers with this study purport that their findings in future may supports increasing lighting intensity at schools to help prevents or slow myopia development

There is still much to understand in the relationship between sun exposure and vision development, and we can't forget about the risk of UV damage to the skin and eyes with prolonged times outdoors.  I do recommend bright lighting conditions for reading in all of my young patients, and encourage outdoor sport participation for those with a high genetic risk for myopia or children starting to show myopia at a young age.   And don't forget that sunglasses are still highly recommended to protect the eye from damaging UV rays!