I am an optometrist working most of the time in a community optometric practice and part-time as Director of Research at the Institute of Optometry. I have researched a few topics in optometry, but not until recently myopia. Yet, fifteen years ago, I developed a hatred of myopia and a keen interest in myopia control. This blog retraces my personal journey into myopia control and explains why I believe that this is the most important development for optometry that has taken place during my career.
Figure 1 represents a situation that will be very familiar to any community optometrist. A young boy, Ben, with two myopic parents, whose normal hyperopia started reducing at about the age of 4 years until, at 6 years of age he became myopic.
Figure 1 shows that the myopia started to progress quite rapidly and with such a young start and rapid progression it seemed inevitable that this boy’s destiny was to be a high myope. To any community optometrist this is an unremarkable scenario, but to me it was personal. This little boy just happened to be my son. As an optometrist, I was all too familiar with the mildly increased risks of ocular pathology in later life associated with myopia. Suddenly. the word “mildly” was not as reassuring as it had seemed when I had quoted this to many patients over the years. I wanted to do whatever I could to decrease the risk of high myopia.
Ben was esophoric at near and some studies suggested that for esophoric myopes the progression of myopia can be slowed by multifocal spectacles.1, 2 So, I prescribed progressive addition lens (PAL) spectacles. As Figure 2 shows, these had minimal effect on what seemed to be an inexorable progression of the myopia. At every eye exam I always discuss contact lenses with ametropic children, but Ben showed no interest until in 2004 he asked for soft contact lenses. We discussed Ortho-K but he was not keen. So, at the age of 10 years I fitted him with single vision daily disposable contact lenses.
The literature indicates that single vision contact lenses (SV CL) have no effect on myopia progression3 and Figure 2 shows this to be the case for Ben. By this time, I was starting to become intrigued by publications of case control studies indicating a beneficial effect of Ortho-K at slowing myopia progression.4, 5 However, Ben was not interested in any type of contact lens with the word “rigid” in the name and I still had reservations about any form of overnight contact lens wear. The hypothesis that Ortho-K was having an effect at slowing myopia by correcting relative peripheral hyperopic defocus (RPHD)6, 7 was starting to sound convincing and I was interested in the work of Dr Tom Aller8, 9 at creating a similar effect with centre distance multifocal contact lenses. My son and wife were just as keen as I was to slow the myopia and so in 2010 I fitted Ben with Proclear (later replaced by Biofinity) centre-distance multifocal contact lenses.
Figure 3 shows that the myopia stopped progressing soon after Ben was fitted with multifocal contact lenses. However, it is unwise to confuse an association with a cause and it is quite feasible that the myopia would have stopped progressing at the age of 16y even if Ben had not been fitted with multifocal lenses. Figure 4 shows, in the COMET study, that myopia typically does not stop progressing until the early twenties, but it certainly can stop sooner.
To me, as a parent, if the multifocal contact lenses were responsible for slowing or halting Ben’s myopia progression then I felt guilty about not having recommended this approach sooner. I had the excuse that good evidence was only just starting to accumulate that myopia progression seemed to be slowed by between one third and two thirds with Ortho-K4, 5, 10-16 and with soft lenses whose multifocal design may correct RPHD.8, 9, 17-21
My experience with Ben and new interest in the research literature, especially a seminal paper by Flitcroft,22 led to a change in the way that I thought about myopia. I have always disliked spectacles, and anything that led people to have to wear them. But now I started to view myopia as the enemy and to feel personally emboldened, and indeed obliged, to do battle with myopia. It was my duty to give parents and children the option of choosing, if they wished, to join with me in trying to slow the progression of myopia.
Case 2 is a good example of what can happen when child, parent, and practitioner set their mind to do what they can to slow myopia. In 2009 this 10y old girl was developing myopia and also had a decompensated esophoria at near.23 Bifocal spectacles solved the distance blur and eased the near symptoms, but as Figure 5 shows they did nothing to slow the myopia progression. After discussion of the options with the child and parents, they decided to undergo a fitting with centre-distance multifocal contact lenses.
Multifocal contact lenses worked very well for Case 2 and Figure 6 shows that after she was fitted with centre distance multifocal contact lenses the myopia stopped progressing and even reversed a little. Case 2 was only aged 11y when she was fitted with multifocal contact lenses and so, unlike Case 1, it is extremely unlikely that the myopia would have stopped progressing this soon had she not undergone myopia control. Case 2 moved away in December 2014 but long before that I had been changed as an optometrist by my experience with these early cases and by emerging research publications. I was no longer prepared to surrender to myopia and simply watch, helpless, as it ran its course. When the child and the parent agree, we will fight together to do all that we can to slow the progression of this condition.
A few words of caution should be added, not least because of the natural bias to only present “good” cases as case studies. The treatment effects that have been described in this blog are based on average results in clinical trials. Some patients, like Case 2, do better than the typical results in the trials. But for others the opposite is true and for some cases the interventions described here show no effect at myopia control. At present, we cannot predict which cases will be successful, although there are some indications that children with esophoria at near and/or a high accommodative lag are likely to benefit most from myopia control. Kate Gifford’s excellent Myopia Profile tool highlights this and other risk factors for myopia development and progression.
Contact lenses should only be fitted to children who are motivated and hygienic, and that goes for their parents too. Also, it is not for the practitioner to decide whether to undertake myopia control. The practitioner’s role is to inform the child and parents of the options and let them decide whether myopia control is for them. In my view, every optometrist should give this informed choice to every myopic child and parent.
I think that the development of interventions that allow the optometrist to combat myopia progression represents a landmark for optometry. We are changing from a profession that corrects to a profession that treats. This is much more than just a change of words. Some members of the public have always viewed our profession with scepticism as they feel that we benefit from the correction of refractive errors. I think that we now have the opportunity of redefining our role; to that of a practitioner who works with parents and patients in a common goal of minimising the burden of refractive error. My personal journey into myopia control has been a fascinating and rewarding development of my role as an eyecare professional. I hope that our profession’s journey in myopia control will accelerate and that one day we may have interventions that will be effective at reversing and curing myopia.
I am grateful to my son for giving me permission to write about him in this blog.
Professor Bruce Evans is the Director of Research at the Institute of Optometry in London, has published over 250 articles and several books, including textbook Pickwell’s Binocular Vision Anomalies. Bruce owns an independent practice in Brentwood, Essex, England, and in his spare time is an avid sailor.