10 year use of low dose atropine for myopia control

We know that low dose atropine has been used to control myopia progression for a number of years now. It is still not approved by the US or Chinese FDA partially because long-term safety data are lacking. Previous studies demonstrated 2 years of using to be safe and effective. But myopia control is a long-term thing, maybe up to 10 years if a child starts to develop myopia from an early age (6- 8 years of age). 

Well now there is a study in Taiwan following children using low dose atropine for 10 years. This is a cohort study, no controls, and with only 23 subjects. Every child (that had myopia) was on low dose atropine for the entire 10 years and monitored every 2-4 months to check their refraction and axial length. It is certainly not a controlled or randomised study, and with a low sample size. However, I think it gives us a lot of information in a clinical setting on what to expect once a child is on low dose atropine for myopia control long term.

They also adopted a commonly used clinical approach, stepwise increase in treatment dosage if the treatment effect is not enough. For example, every myopic child started with 0.05% atropine. If a child did well on this, they continued this dosage throughout the 10 year period. If however their myopia continued to progress more than 0.50 D every 6 months, then they were switched to higher concentrations of 0.1%, 0.25%, and until 0.5%. A high concentration of 1% was not used.

In my clinic (and perhaps many others), I usually start with even lower concentration, 0.01%, which has been clinically proven to be effective in myopia control and with the least side effects including pupil dilation, light sensitivity and blurry near vision. I would go up to 0.02% and 0.05% if myopia control is not achieved, and I seldom go higher than 0.05% because at this point the side effect is noticeable and may interfere with normal study and life of a child. Eye doctors in Taiwan are more aggressive in myopia control in terms of using atropine and I thank them for the study. I always wonder whether I should ramp it up, and if higher concentrations are effective, then maybe it’s worth the side effects (and potentially risks of using this for 10 years).

This study answered my question to some degree. First of all, 65% patients were only using 0.05% atropine throughout the study, which means 35% patients did not respond well to the initial low dose. This is a high number. Remember 0.05% is already a higher concentration than the most commonly prescribed 0.01%, and still ⅓ of children do poorly on it. When we encounter children like this (and we will), do we further increase the dosage? In their study they did, and what they discovered was that for those who did not do well in the initial low concentration of atropine, despite the stepwise increase in the atropine concentration, their myopia control was still worse than the kids who responded to the initial low dose atropine. There were vast inter-individual differences, but the mean numbers look like this: the responding kids started with -1.5 D and progressed to -4.7 D after 10 years, whereas the poorly responding kids started with -0.9 D and progressed to -6.6 D. Their study did not have a control, but based on natural history of myopia progression in their population, they predicted about -7.7 D if no myopia control was done at all. So for those that respond to atropine, a reduction of 3 D of myopia over 10 years is quite good, especially it prevents these kids from developing high myopia (more than -6.0 D), which is associated with more retinal related complications. On the other hand, 10 years of high dose atropine in children who were poor responders resulted in only 1 D of myopia reduction, it seemed less worthwhile, considering the burden of using drops daily for 10 years and the side effects associated with dilation. Of course, this is purely based on a mean value, and individuals can be quite different, and for some, maybe 1 D reduction is still something that helps. 

But the lesson here is that if a child responds poorly to low dose atropine, merely increasing the concentration may not be the answer. They may be better off with additional or alternative control methods, such as ortho K lenses or multifocal soft contact lenses. 

Another outcome is that they did not find significant side effects with 10 year use of low dose atropine drops. The study also claimed that the children were not prescribed PALs. That is interesting, considering that atropine at concentration of 0.1% or above will have significant dilation and cycloplegic effects. Given that they used higher concentrations, it can be assumed that 0.01% atropine can also be used without significant side effects for up to 10 years.

So the take home message is that long term use of low dose atropine (10 years) may be safe and effective, but if a child responds poorly to low dose atropine, then they may benefit more from other methods of control. But keep in mind that this is a limited study with small number of patients. We still wait for larger scale and better controlled study.

The study cited in this article:

Chuang, MN., Fang, PC. & Wu, PC. Stepwise low concentration atropine for myopic control: a 10-year cohort study. Sci Rep 11, 17344 (2021). https://doi.org/10.1038/s41598-021-96698-6

Crocodile tears

A man in his 30s came in because he saw flashes of light for 20 minutes two days ago.

He was having very blurry vision and could not focus as well at the time, but it all resolved on its own and he remained symptom-free. After a thorough dilated exam I determined that his retinas were completely normal and his symptoms were most likely from ocular migraine. 

Then he brought up something else completely unrelated. For three years now whenever he ate something his right eye would tear up and it’s always only the right eye. That eye was not red, itchy or painful, it simply teared up a bit. 

He did not have dry eye. And both of his eyes were white and quiet with no sign of tearing at the time. His description sounded almost like crocodile tear syndrome. This is a very rare condition where the nerve that supplies the salivary gland somehow also goes to innovate the lacrimal gland which secretes tears. When he’s having a meal his salivary gland gets a signal to start secreting saliva, and that cross talks to his lacrimal gland which makes his right eye tear up. This often happens after nerve injury when the nerve tries to repair itself and makes an inadvertent mistake. This is called aberrant nerve regeneration. But he denies any facial or head injury. He reports to be completely healthy and taking no medication. 

The treatment for crocodile tear syndrome is to inject Botox into the lacrimal gland so that a part of the gland doesn’t work and therefore not too many tears are produced. In his case this doesn’t really bother him so we will just monitor.

Can you use ortho K lenses and atropine together to control myopia?

We know that ortho K lenses and low dose atropine (0.01%) both can slow down the rate of myopia progression by about 50%. People often wonder whether by combining the two, we can slow down the progression even further.

Here is an article looking at a combo of the two in 73 Chinese children who have very fast myopia progression. They discovered that additional atropine 0.01% did not result in significant difference compared with ortho K lens alone in terms of axial growth.

This is disappointing. However, this study looked at children with fast myopia progression despite using ortho K lenses. Also only a small number of children were evaluated. In addition, this is a retrospective study, meaning authors looked at the data later, rather than a randomized controlled study, so there could be factors stewing the results.

Anyway, we await more studies to see whether the two have synergistic effect.

Reference:

Chen Z, Zhou J, Xue F, et al, Two-year add-on effect of using low concentration atropine in poor responders of orthokeratology in myopic children British Journal of Ophthalmology Published Online First: 11 March 2021. doi: 10.1136/bjophthalmol-2020-317980

Increased myopia among children during COVID-19

Covid-19 has really affected so many aspects of our lives. With all that isolation inside, and the remote learning with digital screens, parents worry about their kids’ health. Many worry this will do great havoc to their eyesight, and they are not wrong.

Research has shown that confinement to home due to covid-19 is associated with an increase in myopia. Scientists have been monitoring the refractive error of 123 535 Chinese children since 2015. While the refractive error was showing a pretty steady trend in kids 6 to 8 years of age from 2015 to 2019, there was a sharp and dramatic change toward myopia in 2020 (Figure 1). Many Chinese children already don’t get enough outdoor activities and spend way too much time studying, and the covid-19 put extra strain in terms of even further decrease of outdoor time and increase of screen time.

Figure 1. Young children show a dramatic increase in myopia in 2020 compared to previous years [1]. Figure from reference [1]

I only hope that with universal vaccination and a good hygiene habit that we have formed during the past year, children will be able to be back to school and enjoy normal outside activities soon. If you think you child may have trouble seeing, please bring them to an eye doctor.

[1] Wang J, Li Y, Musch DC, et al. Progression of Myopia in School-Aged Children After COVID-19 Home Confinement. JAMA Ophthalmol. 2021;139(3):293–300. doi:10.1001/jamaophthalmol.2020.6239

Myopia and anxiety

A friend who is a rehabilitation therapist in China told me some interesting observation he has had while treating myopic children. He noticed that for those children who are more anxious, their myopia progressed faster, versus those who are calmer. So he asked me whether anxiety and other psychological factors may contribute to myopia development and progression.

Now I know that when I was 10 and started becoming myopic, I had a lot of anxiety and depression, for the reason that I could not see the blackboard in class! Every school year we went to the hospital to have physical exam and the vision exam was the most anxiety-inducing. I would squint, guess, and peek at the tumbling E beforehand trying to memorize them. My face became red and my hands sweaty. Yes I am ashamed to admit that I cheated in the vision screening in elementary school to get away with a failed report to the teacher and my parents. Why did I do that? As a child I could not describe it exactly. But I did not want to wear glasses and became different from everyone else. Plus, as a straight A student, a failed test in any form was not acceptable.

More and more I found it difficult to see the board. I would nonchalantly walk up to the board then back to my seat (fortunately I sat in the middle so did not have to walk too long to disturb the other students). I would peek at my desk mate’s notes to see what’s going on. I became afraid of math classes because the numbers were small. Eventually I had to tell my parents that I had trouble seeing the board. I remember feeling ashamed when I had to tell them. It’s as though I contracted a disease that I should not have. Though the science at the time was not clear, at least to me, I knew that I was to blame for becoming near-sighted. I was always reading, day and night. Not necessarily school-related, but I was hooked by fictions, story books, magazines and newspapers, anything that had prints on them. Outside classroom, I would read on my own. During summer and winter vacation, I would still be reading books from the library. My dad who’s a teacher and scholar, was the role model that I took after. He did not stop my prolonged near work. My childhood home was very dark, with rather dim lighting. Plus my dad also had myopia though my mom had hyperopia. Thus odds were really against me and no surprise I was among the early ones in my class to wear glasses. That was in the early 1990s, at age 10 I developed myopia while majority of my classmates were still emmetropic. Today probably majority of kids in a 4th grade classroom are wearing glasses. Times have really changed.

I remember going to the hospital to have my eyes examined. The doctor put eye drops in my eyes, I had to wait for a long time, before someone put a strange-looking frame on my face and showed me a bunch of different lenses. I was asked to read letters on a chart, and I felt strange that I was able to see some tiny letters. I had to say that this cycloplegic trial frame refraction was up to American standard even to this day. Thanks to my small town ophthalmologist, I was finally able to see. I was -2.00 in both eyes that day and I no longer had to walk up to the board to see small prints.

Back to our question on myopia and anxiety. My own experience told me that as a myope without glasses, I definitely felt anxiety. After wearing glasses, my vision was back, but I felt a kind of depression because I had to rely on glasses and I hated having to glasses. I went through all 5 stages of grief: denial, anger, bargaining, depression and acceptance. I thought that if I looked far away long enough, my eyes would be back to normal. I was mad at myself for abusing my eyes without a break on those stupid books. I constantly regret it and promised I would trade in some years of my life in exchange for normal eyesight. I was depressed that I had to wear glasses and looked ugly. Eventually of course I accepted this imperfect aspect of me. After all, there were so many other things that were not perfect so why focus only on myopia?

As an optometrist, myopia is one of the most common conditions we treat. It’s so common we almost consider it ‘normal’, routine and benign. We rarely considered the psychological aspect of myopia, when in reality this condition hit children and adolescents, who are at a vulnerable age.

Now the science part of this article. Research has shown that myopic teenagers had more anxiety than their peers, and boys with myopia had more anxiety than girls with the same condition 1. However, personality profile and psychophysical stress do not seem to play a primary pathogenetic role in myopia 2. So that is good, you can feel tortured by the fact that you need thicker glasses, but the sadness alone does not make your eyesight worse.

References:

1.            Łazarczyk JB, Urban B, Konarzewska B, et al. The differences in level of trait anxiety among girls and boys aged 13-17 years with myopia and emmetropia. BMC Ophthalmol 2016;16:201-201.

2.            Angi M, Rupolo G, De Bertolini C, Bisantis C. Personality, psychophysical stress and myopia progression. Graefe’s Archive for Clinical and Experimental Ophthalmology 1993;231:136-140.

Will eating sugar make myopia worse?

Myopia has become a global epidemic, affecting kids of school age, sometimes as early as 6 or 7. Left untreated, myopia may progress 1 diopter each year, resulting in high myopia when kids become adults. Myopia is not just an inconvenience, it is an eye disease that significantly increases a person’s risk of developing retinal detachment and myopic macular degeneration, both can lead to blindness.

Naturally parents become concerned when their kids fail the vision screening at school and have to wear glasses to see well. As food is a key part of our health, many often wonder if food contributes to myopia development. For example, does eating sugar and refined carbohydrates increase myopia? Surely sugar is bad for your teeth and just bad for your health in general. Is it also to blame for myopia?

Will sugar coma cause you to see worse?

When I was a student at New England College of Optometry in Boston, we learned extensively on myopia, which is a major topic of interest for optometry. While many factors affect myopia, for example, genetics, prolonged near work, lack of outdoor activities, sugar intake was never mentioned as a factor to affect myopia. Yes diabetes can affect a person’s vision by making them temporarily more myopic or hyperopic, but that is reversible and after blood sugar levels are controlled, the eye returns to baseline refractive state. Most people, especially school aged children, do not have diabetes or constantly fluctuating sugar levels. So is there any evidence for a role of sugar in myopia that is not in context of diabetes?

It turns out not many studies have been done on this topic. In 1956, Gardiner proposed that carbohydrates and fats in the diet could cause myopia 1, but this hypothesis was discarded later in the scientific community. When this happens, it’s either because not enough research was done to support it, or that it did not hold water by subsequent research. In deed there was a scarce of literature on this topic. But one actually found that more sugar intake did not increase risk of developing myopia in children 2. This study in turn, found out that too much saturated fatty acid in the diet correlated with more myopia.

Most recently a French study evaluated 180 children aged 4-18 via questionnaire about their diet habits, and discovered that for girls, more sugar and refined carbohydrates correlated with more myopia, but in boys, this was actually the opposite, that is, when boys eat more sugar/carbs, they show less myopia development 3. This type of study has flaws in that it relies on questionnaire which can be highly subjective. In addition, many variables were not controlled, such as outdoor time, reading and screen time. Even if it’s to be trusted, the study like many epidemiological studies, evaluate a correlation, not causation. Besides, how do you interpret the data that sugar reduces myopia risks in boys? Would you recommend boys to eat more sugar and refined carbohydrates? I don’t think so.

In summary, little evidence exists to indicate sugar or refined carbs increase or decrease risks of myopia. Maybe this is just a factor that has not much to do with myopia. To advocate better oral hygiene and health, we certainly want children to control their intake of sugar and refined carbs, possibly for everyone really, not just kids. However, if you think that by eating less sugar you will not develop myopia, you are up the wrong tree.

References

1.            Gardiner PA. The diet of growing myopes. Trans Ophthalmol Soc U K 1956;76:171-180.

2.            Lim LS, Gazzard G, Low YL, et al. Dietary factors, myopia, and axial dimensions in children. Ophthalmology 2010;117:993-997 e994.

3.            Berticat C, Mamouni S, Ciais A, Villain M, Raymond M, Daien V. Probability of myopia in children with high refined carbohydrates consumption in France. BMC Ophthalmol 2020;20:337-337.

Fake membrane

A man in his late 40s came in with blood shot and swollen eyes. 5 days ago while in the gym he rubbed his eyes after cleansers still on his hands. Since then each day both of his eyes were feeling worse with foreign body sensation, itchiness, pain and discharge. He went to urgent care 2 days ago, was given antibiotic drops and ointment, but felt it’s not helping. His conjunctiva (white part of eyes) were the most swollen that I had seen. Unfortunately I did not take a photo, but found one on the internet that quite resembled his eyes at the time as shown below.

Image 1. Conjunctiva chemosis (swollen conjunctiva). Image from https://images.app.goo.gl/V48FJXf32i9gdeov5

Cornea (black part of the eye) was clear. At the time I thought this was toxic/allergic conjunctivitis, so prescribed a steroid drop to use 4 times a day for 7 days. 

A week later, he came back, reporting improved symptoms (pain 3/10 from 5/10 previously), but still lots of discharge. This time, the swelling was gone, the redness almost resolved, but when I pulled his eyelid down, there were white pseudomembranes (fake membranes) in both eyes, more in one eye than the other. Below is again from internet, showing similar to what I saw.

Image 2. Conjunctival pseudomembrane, a white membrane developing inside the eyelid. Image from https://images.app.goo.gl/bUz4K3c7xtfaDYaYA

Now this made me rethink the diagnosis. Pseudomembranes are often seen in infectious conjunctivitis caused by nasty bugs such as Corynebacterium diphtheriae, Neisseria gonorrhoeae, Streptococcus pyogenes and adenoviruses, some of these are highly contagious. I asked whether anyone else in the household developed pink eyes, and he said no. He had no systemic symptoms or swollen lymph nodes, which were a good sign. Pseudomembranes can also be caused by toxic and allergic agents, and even foreign bodies [reference 1]. So at this point I was still going with allergic conjunctivitis, but these other infectious causes were now on the back of my mind, making me uneasy. So I stopped the steroid drops and switched to an antibiotic/steroid combo drop, as well as adding an antibiotic ointment at night. Of course, the pseudomembrane had to be removed otherwise he would not get better.

1 week later he came back, this time he’s much better, no discomfort, not much discharge, no swelling or redness. Exam revealed residual tiny papillae, and the membranes were gone! 

To summarize, pseudomembranes can be caused by infections, toxins, foreign bodies or allergies, and to treat it the underlying cause needs to be addressed, and pseudomembranes need to be removed promptly.

Reference:

[1] Ho D, Lim S, Kim Teck Y. Pseudomembranous Conjunctivitis: A Possible Conjunctival Foreign Body Aetiology. Cureus. 2020;12(5):e8176. Published 2020 May 18. doi:10.7759/cureus.8176

Gray floater in an elderly lady

Floaters can be so common, yet not all floaters are the same. Here is another example.

An 84 year old nice lady came for an urgent visit as she started noticing a greenish gray floater in the right eye for 1 week. She did not notice any flashes. Her right eye saw 20/400 with no improvement with pinhole (this usually means that vision cannot be improved with glasses). Her left eye was able to see 20/30.

It’s impressive that she had not had cataract surgery yet, and only had a moderate amount of cataract. One look at her macula in the right eye revealed why she saw this gray ‘floater’. There is a blob of blood there as shown in images below. 

Figure 1. New membrane (arrow head) and bleeding (***) in the macula of the right eye.

The other eye only had mild drusens in the macula, indicating early age-related macular degeneration.

So this may be a case of very asymmetrical presentation of AMD with the right eye affected by wet AMD with acute bleeding and vision loss, and left eye only affected by mild dry AMD.

I referred her to a retinal specialist for treatment.

See my other articles on “floaters” and related eye phenomena.

https://bostoneyeblink.com/2019/11/28/annoying-floaters-where-do-they-come-from-and-what-should-you-do-about-them/

https://bostoneyeblink.com/2019/09/28/floaters-in-a-young-woman/

Does ortho K increase risk of glaucoma?

The ortho K lens is popularly used to reshape cornea, correct vision and slow myopia progression. Read my previous post here (https://bostoneyeblink.com/2016/09/09/ortho-k-why-do-it-and-is-it-risky/)

People are often concerned about potential side effects or complications of wearing ortho K lenses. We previously discussed that corneal infection is a concern, but proper hygiene and care minimize this risk. It is a hard lens that touches on the cornea, will this have any effect on glaucoma or eye pressure of the eye? A colleague of mine recently saw an 18 year-old patient interested in ortho K for his myopia, who has a family history of glaucoma, and showing some questionable visual field finding himself. My colleague is worried about what ortho K may do to patient’s eye pressure and risk of glaucoma.

First of all, glaucoma is exceedingly uncommon among kids and young adults. Second, even if someone has glaucoma, it is not a contraindication for wearing ortho K lenses. Research has actually shown that wearing ortho K lenses overnight reduced eye pressure slightly [1, 2].

Of course, if you have glaucoma, you need to regularly see your glaucoma doctor to check eye pressure, health status of the optic nerve and visual field function, whether you wear any type of contact lens including ortho K lens or not. But people with or without glaucoma, if eligible for ortho K lenses, can certainly choose to wear them.

References:

[1] M.R. Romano; A. Calossi; F. Romano; G. Ferraioli, Intra–Ocular Pressure After Overnight Orthokeratology, ARVO Annual Meeting Abstract, Investigative Ophthalmology & Visual Science May 2006, Vol.47, 2391

[2] Chang CJ, Yang HH, Chang CA, Wu R, Tsai HY. The influence of orthokeratology on intraocular pressure measurements. Semin Ophthalmol. 2013 Jul;28(4):210-5. doi: 10.3109/08820538.2013.768679. Epub 2013 Apr 29. PMID: 23627528.

Doc, my eyes still hurt, now what?

Recently a patient complained to me: ‘Doc, my eyes still hurt.’

I asked: ‘have you tried the artificial tears I recommended to you?

‘Yes, it doesn’t do any good.’

‘How many times did you put in a day?’

‘I just did that once and it did not work.’

‘I see. How about the warm compress?’

‘Not working either.’

‘How long did you do it and how many times a day?

‘Once or twice, I forgot.’

‘Are you taking the fish oil supplement?’

‘Yes. Did not feel any different.’

Here I have a patient who two months ago came to me for dry eye. He reported trying restasis from his previous eye doctor for months but no relief at all. Eye exam showed typical meibomian gland dysfunction (MGD) and poor tear film quality, without blepharitis or corneal staining. So this is a case of MGD-induced dry eye, that’s why I started him on eyelid warm compress 5 min x 2, and fish oil 1000 mg x 2 daily, with artificial tears as needed, up to 4 times daily. I asked him to follow up in 1 month. At which time he was not doing any of the things I asked, and of course his dry eye symptoms continued. After re-education, I asked him to do these consistently and follow up again in 1 month. He has probably done some of this now, but not consistently, and given up very quickly.

Rather than drilling him again for being more compliant with the treatment regimen, I offered him an alternative, which he clearly came looking for. I would like to refer him for a lipiflow treatment. I explained what it is, how it is done, and why it works. Then I told him that it’s not covered by insurance and may cost $1-2,000 for one session.

After a short moment of silence, he told me that he would like to give warm compress another try. And that he just started taking fish oil last week and would like to see if doing this for longer may help. I agreed, and asked him to return in 6 weeks to evaluate on progress.

No one likes having the dryness, foreign body sensation, redness, burning and tearing caused by dry eye. Fortunately there are effective treatments such as warm compress and artificial tears, and often these are enough to control dry eye symptoms. Unfortunately these treatments require consistent and long-term use. There is no cure for dry eye, which is a chronic condition and may require life-long management. When it comes to dry eye treatment, compliance is key. There are certainly those unlucky people who despite doing everything right still suffers from dry eye. But fortunately those are the minority.

For more information on dry eye and treatment, you can visit my previous posts and video.

https://bostoneyeblink.com/2020/05/25/dr-ding-dry-eye-disease-and-treatment/

https://bostoneyeblink.com/2017/08/06/when-artificial-tears-just-dont-cut-it-other-treatments-of-dry-eye/

https://bostoneyeblink.com/2016/06/28/why-are-your-eyes-dry/