What is orthokeratology (ortho-k)?
Orthokeratology treatment, also known as Ortho-K, OK or corneal refractive therapy, is a non-surgical, reversible procedure in which specially designed contact lenses are applied just before going to bed, and gently mould the cornea (front surface of the eye) to a flatter curvature, thus reducing myopia (short sightedness) and astigmatism (the irregular shape of the cornea). This gentle and gradual re-shaping allows clear and natural vision without the need for prescription glasses or contact lenses during the day.
Wearing orthokeratology custom-made rigid contact lenses also gently reshapes the peripheral cornea also, and it’s the moulding on the peripheral cornea that reduces the worsening of short sightedness.
What is ortho-k? Watch this video:
Ortho-K and myopia control – information for parents
How ortho-k corrects myopia & slows progression
Orthokeratology lenses are applied to the eyes surface just before bed. On awakening, the lenses are removed and you can see clearly all day without glasses or contacts! So the contour change is the reason orthokeratology slows myopia progression, and the side benefit of that contour change means you can see well with the lenses removed.
These custom made contact lenses are worn during sleep and removed upon waking, the effect lasting from several hours in the first week to several days as therapy progresses.
Ortho-K lenses use fluid surface tension to gently reshape the cornea and the process has been likened to the use of retainers by orthodontists to maintain straightened teeth. Like orthodontists or orthopaedics, “ortho” means changing or correcting, and “kerato” is the Latin word for cornea. So an orthokeratologist changes the corneal contour and this anatomical change is the reason this treatment slows the progression of myopia. Unlike bones and teeth, the cornea is elastic, so these lenses are worn every night to retain the moulding effect once the correct corneal shape has been achieved, just like a retainer for your teeth.
It is a very effective treatment for controlling myopia as it creates an imprint on the cornea. The imprint persists, provided you keep sleeping in the lenses, and washes away when you stop. Within a week of no lens wear, the cornea bounces back to its natural shape and former prescription. So it’s beauty is it’s reversible, adaptable to script changes, and surgery free.
Ortho-K isn’t new. The moulding effect of the cornea induced by contact lenses was learnt in the 1940’s. The fact you could mould the eye to improve vision was discovered almost by accident back in the 1960s. Since then the technology, accuracy and safety of orthokeratology has dramatically improved. Our ability to accurately map the corneal changes, along with the development of new contact lens materials that allow extremely high levels of oxygen to reach the cornea, and the introduction of computer-controlled precision lathes that manufacture these corneal moulds to exact design specifications, have meant its popularity has grown.
Orthokeratology has been a very successful, well researched, effective treatment for myopia control for over 20 years. OrthoK has been shown in scientific studies to significantly slow down the progression of myopia by 32-100% according to the literature. At Custom EyeCare, we’ve found in most patients it nearly always STOPS vision from getting worse.
Orthokeratology is suitable for all ages but it has a special advantage of slowing myopia progression in children & teenagers. It can be a more difficult treatment in very young children. The youngest little orthok wearer at Custom Eyecare was 6 years old. She is now a growing teenager in high school and still enjoying her orthokeratology treatment.
Orthokeratology (OrthoK) overnight vision correction is available for adults, teens, & children at Custom Eyecare in Newcastle.
Click here to arrange your baseline initial examination to commence ortho-K
FAQs on ortho K
Is ortho-k new?
Orthokeratology was discovered almost by accident back in the 1960s but the technology then was too limited to provide good results. In recent years, advances in computerised corneal mapping & lens manufacturing technology allowed a huge increase in accuracy and reliability.
Very few optometrists in Newcastle or the Hunter Region of NSW have the equipment and expertise to offer orthokeratology, but it’s available at the Myopic Clinic within Custom Eyecare in Newcastle’s Darby Street.
How does orthokeratology work? What happens to my eyes?
The outermost layer of cells of the cornea (the epithelium) is normally around 50 microns, or 0.05mm thick. In orthokeratology, a very thin layer of tear fluid is trapped between the back of the contact lens and the cornea, and pressure differences within this tear layer cause thinning and thickening of different zones of the corneal epithelium, effectively changing its shape or curvature. In the treatment of short-sightedness (myopia), the central area of the cornea is flattened, allowing an improvement in long distance focus. The suction forces are so gentle that orthokeratology lenses worn overnight are usually more comfortable than traditional lenses worn during the daytime. You can’t feel the cornea changing, but of course you can see the improvement in your vision.
Ortho-K uses fluid surface tension to gently “pull” or reshape the cornea into the correct shape overnight while you sleep, to correct your vision.
After the contact lens is removed in the morning, the cornea very slowly starts to return to its original shape, so vision gradually returns to its previous state. How quickly this happens varies, but it usually takes at least a day or two before a change in vision becomes noticeable. In other words, you will need to continue to wear your ortho-K lenses on an ongoing basis (either every night or most nights) to maintain clear vision.
Stabilisation and reinforcement of the effect occurs over the next few days & weeks, depending on the initial degree of myopia or astigmatism and the rates of change in corneal shape. As the therapy progresses, your overnight lenses provide you with clear vision for longer periods of time, so you may be able to skip a night here or there.
Most people comment that they forget they have lenses on after the first night or two of sleeping with them in.
We monitor the vision and corneal contour changes at each review appointment
To find out more about the process of Ortho-K – watch this video:
What are the advantages of ortho K?
A child’s favourite advantage is being able to see all day every day without wearing glasses.
This is especially fabulous when it comes to sport, especially water sports such as swimming or surfing. It’s also great for social reasons as getting kids out of glasses gives a big boost to self-esteem.
Who is suitable for orthokeratology?
Ortho-K works just as well on children as adults, and so the lower age limit really depends on the maturity, motivation, willingness and ability of the child (with parental supervision) to insert, remove & clean the lenses hygienically. In our practice we have successfully treated short-sighted children as young as six years old with orthokeratology.
Find out more about who is suitable for Ortho-K in this video:
Is there an age limit for orthokeratology? Watch this video:
What are the steps involved in Ortho-K?
The first step is a comprehensive initial examination with one of our optometrists to assess the vision and general condition & health of the eyes. Also at this visit the contours of your corneas are measured using a computerised corneal mapping system (it’s fast and comfortable). This provides you with an opportunity to discuss the likely effectiveness of the procedure with more precise background information.
The next step is the fitting. Based on your individual eye shape and prescription, a pair of custom made lenses will be ordered, which may take approximately 2-3 weeks.
When your lenses arrive we’ll show you how to insert, remove, and care for your ortho-K lenses. We allow an hour for this visit, to ensure you’re comfortable with the insertion & removal technique, which is different to handling soft lenses. Inserting the lenses is fairly easy; getting them out takes a little more practice, but we’ll make sure you’re comfortable before you leave the practice!
Your new lenses are then worn for the first time that night. The following morning we see you for your first review appointment at 9:00am. Your vision isn’t expected to be perfect after the very first night, but most of the improvement does occur rapidly during the first few days. You may need to wear a weak pair of temporary disposable soft lenses, or an older pair of your glasses that are weaker in prescription, during the first day or two until your vision is fully corrected.
During the initial six months, and especially over the first weeks, your optometrist will ask you to return for review visits to assess not only your vision but also the fitting of the lenses, which is critical to your success. Sometimes, a modified contact lens may need to be ordered for you which is included in your treatment fees.
After the initial treatment period, regular ongoing review visits (6 monthly) are still necessary, to ensure the good health of your corneas and the best performance of your lenses. It’s important that you come for these regular check-ups even if you are happy with your vision.
What are the fees for Orthokeratology?
Once you’ve had your baseline eye examination and corneal topography mapping ($186 for both) showing that you’re suitable, the cost of your orthokeratology treatment program is typically $2100, but can be up to $3250 for higher prescriptions. This includes your first pair of lenses, a starter pack of solutions and accessories, any lens modifications or remakes required during the fitting process, and all fitting and checkup visits for the first six months. After that, you only need routine checks every six months, and lens replacement perhaps every 12-18 months (depending on how well you look after them) at $600 each lens. Over time, the cost of orthokeratology works out to be comparable to wearing regular disposable soft contact lenses and glasses.
You can normally claim a modest rebate from Medicare for the initial baseline consultation. And if you’re in a private health fund with ancillary (extras) cover, you should be able to claim an annual rebate for the rigid gas permeable contact lenses used in orthokeratology (health fund item 812).
Why wasn’t I offered Ortho-K previously?
Ortho-k has been around since the 1960s, but in the past it was not as successful as today due to a lack of suitable contact lens materials and instrumentation. Improvements in breathable contact lens materials (allowing safe overnight wear), accuracy of lens manufacture with specialised computer driven lathes and sophisticated corneal mapping instrumentation (computerised topography) lend to modern Ortho-K being much more predictable and achieving better results.
Can any optometrist provide Ortho-K?
As Ortho-K requires specialised equipment and training, most optometrists do not offer this treatment.
Are there risks with Orthokeratology?
Common and minor lens complications include:
- Mild lens binding on awakening (this is not uncommon and you will be taught how to dislodge a bound lens safely and easily).
- Mild corneal surface abrasions (which will normally heal after a few hours – sometimes the lens shape has to be modified to avoid this; but more commonly it just means the lenses need a good clean!).
- Allergy to disinfection solution (you will be switched to another type of care system).
- Fluctuating vision on certain days after myopia reduction (this could happen if your lenses did not centre properly when you wore them the night before, and again sometimes the lens shape has to be modified to avoid this).
- Haloes around lights at night time (often a modified lens can be ordered to improve this, but sometimes with the correction of higher amounts myopia haloes are hard to avoid).
Contact lenses are a medical device worn on the surface of the eyes so the other risks involved in this treatment are similar to those of regular contact lens wear, which includes eye infections and allergic responses to the contact lens.
No contact lens patient fitted at our practice has ever lost vision due to a contact lens related eye infection, thanks to our detailed hygiene & care instructions, and careful scheduling of review appointments. So, as with any type of contact lens wear, regular checkups and clean lenses on your eye do minimise the risk of problems.
Generally lenses are replaced every 12-18 months for hygiene reasons.
How do I get started?
Orthokeratology begins with a baseline eye examination including precise vision measurement, full eye health assessment, and computer mapping of the shape of your eyes (corneal topography).
Contact us for an appointment where your individual suitability can be discussed. Upon payment of your deposit, your custom designed orthokeratology lenses can be ordered on the same day!
Orthokeratology Research
The studies on ortho K show a 32-100% reduction in myopia progression, depending on which one you read.
The evidence started with a pilot study out of Hong Kong published in 2005 called the Longitudinal Orthokeratology Research in Children (LORIC) study, where they compared 35 kids wearing orthokeratology lenses and compared them to spectacle wearers. At the end of 2 years, the orthokeratology group had significantly less axial elongation (eyeball growth). But the control group was actually from a different study even though they were matched for age, gender and baseline refraction, so not the best study design.
Then in the US, a 6-month pilot study, called Children’s Overnight Orthokeratology Investigation (COOKI) compared a small group of children wearing overnight orthokeratology lenses to those wearing conventional contact lenses by day. All children were aged 8-11 and they found that orthokeratology lenses were more effective at treating the children’s myopia than traditional contact lenses, and there were no serious adverse events.
The COOKI study was followed by the larger Corneal Reshaping And Yearly Observation of Nearsightedness (CRAYON) study in 2009 where they compared orthokeratology lenses to traditional soft contact lenses where the children were grouped with other age and gender matched children who were randomly assigned to either modality over 2 years. The orthokeratology group was found to have 0.16 mm less axial length elongation compared to traditional soft contact lens. Eye growth was slowed by a reported 55%.
From there the Stabilizing Myopia by Accelerated Reshaping Technique (SMART) study evolved. It was a large multicenter, multi year longitudinal study out of Chicago, USA that looked at the same comparison. Children either wore orthokeratology lenses overnight or traditional soft contact lenses by day. The first 5 year results show a statistically significant difference between the two groups of children. Over the three year period the orthokeratology group had only a slight change in their refraction of -0.12D, whereas the control group wearing soft contact lenses progressed more than -1.00D. The unique study design meant lens wear was discontinued at the yearly visit for the orthokeratology patients until all orthokeratology effects had worn off so dropout rate was high.
A cute little study was done by our local orthokeratology gurus at the University of NSW in Sydney which was a randomized 12 month crossover study, meaning they fit one eye with an overnight orthok lens, and the other with a conventional rigid contact lens won during the day. At the 6 month mark the lens/eye combinations were reversed in all patients. The eye that wore a standard rigid lens showed an increase in axial length during both intervals, whereas the eye fitted with a custom orthokeratology lens showed no axial length elongation. So 100% myopia progression control!
Then the Retardation Of Myopia In Orthokeratology (ROMIO) study came out of Asia. This was a 2-year randomized clinical trial which included children aged 6 to 10 years who wore either glasses or overnight orthokeratology lenses. At the end of the 2 years, the average axial elongation in the orthokeratology group was 0.36mm versus 0.63mm in the control group. The conclusion was that on average, children wearing orthokeratology lenses had slower increases in axial elongation by 43% compared to children wearing spherical distance glasses.
These researchers also documented that myopic progression was most rapid in children aged 7 to 8 years. Specifically, among the 7 to 8 year old children, 65% progressed more than -1.00D per year, while among the 9 and 10 year olds only 13% had such a high rate of myopic progression. This has important implications for the timing of interventions to control myopia.
Orthokeratology – Further Reading & Resources
Ortho-K Solution & Equipment Guide
Wikipedia article on orthokeratology
“All About Vision” article on orthokeratology – All About Vision is a huge online publication with independent consumer information on all eye health and vision correction topics.
Orthokeratology Society of Oceania (OSO) – formerly the Orthokeratology Society of Australia (OSA), the OSO supports professional development, education and communication among orthoK practitioners in Australia and our surrounding region.
International Academy of Orthokeratology (IAO) – the global peak body for scientific research and training in orthokeratology
European Academy of Orthokeratology – promotes orthokeratology science & education in Europe
Orthokeratology Academy of America – devoted to the research and education of orthokeratology
