Ortho-k for myopia control in young adults

• Ortho-k is a great option for young adults with active lifestyles, dry eye problems with soft contact lenses, and for people doing water sports 
• Ortho-k is the only treatment with evidence for stabilizing eye growth in young adults with myopia, although the available evidence is limited.
• In young adults, ortho-k for myopia control is as safe if ortho-k is only for vision correction, as long as correct wear and care systems are followed.

Myopia, also known as short-sightedness or near-sightedness, causes vision to become blurred in the long distance, and the need for glasses or contact lenses to bring the eye back into focus.

In most cases, myopia starts in childhood, and then progressively increases typically up until early adulthood when it stablizes.¹ Myopia is a lifelong condition and increases risk of potentially sight threatening conditions in later life, causing the World Health Organization to classify myopia as a global health concern.²

'Myopia control' has become the increasingly adopted term to describe any approach that aims to slow progression of myopia. Myopia control is particularly important in children and young teenagers, because this is the stage in life when myopia is most likely to progress.¹

While myopia progression is less likely in young adults, it can still occur³ and hence there is a potential benefit from myopia control treatment.⁴

Ortho-k is a special type of rigid contact lens which is worn overnight, while sleeping, to gently reshape the cornea (the clear dome at the front of the eye) so that daytime wear of glasses or contact lenses is not needed.⁵

As a way to correct vision, ortho-k was first tried back in the 1960's when it was predominantly used in adults. In more recent years there has been a marked increase in children and teenagers wearing ortho-k, because of its proven ability to slow progression of myopia.⁶

Ortho-k eliminates the need for daytime wear of contact lenses, making it a fantastic option for vision correction for young adults. Freedom from spectacles or contact lenses during waking hours provides the following benefits:

• Working in dry, dusty or air-conditioned environments can be challenging to keep glasses clean and contact lenses comfortable. Ortho-k is a great option here.⁵ 
• Improved eye health safety in swimming or other water sports. Water exposure to contact lenses significantly increases the risk of serious eye infection.⁷
• In young adults who had dry eye symptoms in soft contact lens wear, ortho-k has been shown to improve those symptoms and be a preferred type of vision correction to soft contact lenses.⁸
• For young adults who have progressive myopia, there is a small amount of evidence that ortho-k can stabilize eye growth in young adults with progressive, or worsening myopia.^9.10

How ortho-k slows progression of myopia is not fully understood, however the current consensus is that it favorably alters the way light is focused onto the retina. In addition to correcting myopia, the focus pattern created by ortho-k is believed to send a stop signal to the eye to slow down eye growth.¹¹

The main reason for myopia developing and progressing in children and teenagers is because the eye grows faster than it should, which causes the eye to fall out of focus. Eye growth is typically fastest in children but still occurs as teenagers into early adulthood.^1,3 Consequently myopia can still progress into young adulthood when standard (non myopia control) glasses or contact lens vision correction is used.

Research reveals ortho-k to provide a 50% myopia control effect, meaning that it can slow progression of myopia by around half. While ortho-k is most likely to provide a greater overall myopia controlling effect in younger children, there is strong evidence that ortho-k significantly slows progression of myopia in teenagers with most evidence for teenagers up to 15-16 years of age.¹²

There is some limited evidence that ortho-k can remain effective for myopia control in young adults aged 18 to 29.^9.10 There is a lack of evidence for different myopia treatments in young adults is partly because myopia progression starts to stabilize at this age, with half of young myopes naturally ceasing their myopia progression by age 16.¹

Since recent research shows that almost 40% of people in their 20s will suffer myopia progression in that decade,³ expert advice is that myopia control treatment should ideally continue into early adulthood where possible.¹³

There are a growing number of ways that myopia can be corrected while providing a myopia control effect in children and teenagers including special types of spectacles, soft contact lenses and atropine eye drops.

Ortho-k is one of the best currently available options for myopia control, with the largest amount of research to support its ability to slow myopia progression in children and teenagers.¹³

There is no evidence for special types of spectacles, soft contat lenses or atropine eye drops slowing myopia progression in young adults, and only a small amount of limited evidence for ortho-k.^9,10

In ortho-k, the focusing power of the eye is altered to correct vision during waking hours, so if ortho-k is working well then there will be clear vision and a minimal residual refraction (power of glasses or contact lenses) to measure. A stable refraction over time can indicate minimal myopia progression. Axial length of the eye can also be measured to indicate stability of myopia in young adults.

Yes, in young adults ortho-k for myopia control is as safe if ortho-k is only for vision correction, as long as correct wear and care systems are followed. You do need to be aware that ortho-k increases risk of eye infection, however, current research revels this to be low at around 1-2 cases of corneal eye infection per 2,000 patient wearing years.^14,15

1. Hou W, Norton TT, Hyman L, Gwiazda J; COMET Group. Axial Elongation in Myopic Children and its Association With Myopia Progression in the Correction of Myopia Evaluation Trial. Eye Contact Lens. 2018 Jul;44(4):248-259. (link)
2. The impact of myopia and high myopia. Report of the Joint World Health Organization-Brien Holden Vision Institute Global Scientific Meeting on Myopia. 2015 (link)
3. Lee SS, Lingham G, Sanfilippo PG, Hammond CJ, Saw SM, Guggenheim JA, Yazar S, Mackey DA. Incidence and Progression of Myopia in Early Adulthood. JAMA Ophthalmol. 2022 Feb 1;140(2):162-169. (link)
4. Gifford KL, Richdale K, Kang P, Aller TA, Lam CS, Liu YM, Michaud L, Mulder J, Orr JB, Rose KA, Saunders KJ, Seidel D, Tideman JWL, Sankaridurg P. IMI - Clinical Management Guidelines Report. Invest Ophthalmol Vis Sci. 2019 Feb 28;60(3):M184-M203. (link)
5. Vincent SJ, Cho P, Chan KY, Fadel D, Ghorbani-Mojarrad N, González-Méijome JM, Johnson L, Kang P, Michaud L, Simard P, Jones L. CLEAR - Orthokeratology. Cont Lens Anterior Eye. 2021 Apr;44(2):240-269. (link)
6. Efron N, Morgan PB, Woods CA, Santodomingo-Rubido J, Nichols JJ; International Contact Lens Prescribing Survey Consortium. International survey of contact lens fitting for myopia control in children. Cont Lens Anterior Eye. 2020 Feb;43(1):4-8. (link)
7. Ibrahim YW, Boase DL, Cree IA. How Could Contact Lens Wearers Be at Risk of Acanthamoeba Infection? A Review. J Optom. 2009;2(2):60–6.
8. Duong K, McGwin G Jr, Franklin QX, Cox J, Pucker AD. Treating Uncomfortable Contact Lens Wear With Orthokeratology. Eye Contact Lens. 2021 Feb 1;47(2):74-80.
9. Gifford KL, Gifford P, Hendicott PL, Schmid KL. Zone of Clear Single Binocular Vision in Myopic Orthokeratology. Eye Contact Lens. 2020 Mar;46(2):82-90. (link)
10. González-Méijome JM, Carracedo G, Lopes-Ferreira D, Faria-Ribeiro MA, Peixoto-de-Matos SC, Queirós A. Stabilization in early adult-onset myopia with corneal refractive therapy. Cont Lens Anterior Eye. 2016 Feb;39(1):72-7. (link)
11. Smith EL 3rd. Optical treatment strategies to slow myopia progression: effects of the visual extent of the optical treatment zone. Exp Eye Res. 2013 Sep;114:77-88. (link)
12. Sun Y, Xu F, Zhang T, Liu M, Wang D, Chen Y, Liu Q. Orthokeratology to control myopia progression: a meta-analysis. PLoS One. 2015 Apr 9;10(4):e0124535. (link)
13. Brennan NA, Toubouti YM, Cheng X, Bullimore MA. Efficacy in myopia control. Prog Retin Eye Res. 2021 Jul;83:100923. (link)
14. Bullimore MA, Sinnott LT, Jones-Jordan LA. The risk of microbial keratitis with overnight corneal reshaping lenses. Optom Vis Sci. 2013 Sep;90(9):937-44
15. Bullimore MA, Mirsayafov DS, Khurai AR, Kononov LB, Asatrian SP, Shmakov AN, Richdale K, Gorev VV. Pediatric Microbial Keratitis With Overnight Orthokeratology in Russia. Eye Contact Lens. 2021 Jul 1;47(7):420-425. (link)