Ortho K – twenty questions answered.

Ortho K 20 questions answered

Some of the questions we are often asked are outlined below. If you don’t see your query answered, get in touch!

What is Ortho K?

It is the night time wearing of special lenses that neutralise the eye’s power, allowing clear vision on removal.

What prescription range does it work for?

Generally, up to about -5.00 myopia with about -2.00 astigmatism.  However, in deciding who it will work best for, an accurate eye shape mapping is required as such factors as corneal steepness and prescription orientation can rule out individuals. Eye mapping is extremely important in Ortho K assessment as it is used in the ongoing assessment of treatment. As well as short sight correction, it can also be used for low plus prescriptions.

Why not use normal contact lenses?

The biggest problem for soft contact lens wearers is dryness and lens comfort after a period of wear. While modern materials have greatly improved and more people successfully wear lenses, lens comfort and stable vision is still an issue for people with drier eyes, vdu users and astigmatism lenses. Normal contact lenses are not suitable for certain occupations and sports. In addition to wearing Ortho K  lenses for better comfort, they also have an important role preventing shortsight getting worse. (Short sight has a tendency to get worse as children grow especially where there is a strong family connection. There is now strong evidence that Ortho K lenses help stop or slow myopia progression.)

Will they take long to work?

Ortho K  lenses work from the first night of wear. The full effect may not be achieved in one night but wearers can see there is a big difference on first removal. In the first week of wearing Ortho K lenses, two things are changing. 1) the quantity of correction increases ie how much you can see and 2) the quality of vision improves ie how well you can see throughout the day.

Are they comfortable?

Most new Ortho K wearers are previous soft contact lens wearers. They all report being  more aware of Ortho K lenses in the beginning but once eyes are closed there is no discomfort. By one week, few comfort issues are reported whether eyes are open or closed.

Are they worn every night?

No. Every wearer is strongly encouraged to leave lenses out at least once a week. Some wearers leave them out twice a week. In the early stages of wear, leaving out for a night is important as it reassures wearers that the correcting effect does not evaporate overnight.

Can I see with the lenses in?

For safety reasons, it is essential that you can see with, as well as without, Ortho K lenses in. Should you have to get up in the middle of the night and drive  – no problem.

What about eye infections?

Wearing any type of contact lens brings a slight increased risk of eye infection. While the record of Ortho K is very good, it is essential that wearers take responsibility for basic hygiene rules and should consult their eye care practitioner, when in doubt.

I have hay fever. Can I wear Ortho K lenses?

Yes. As you are only wearing the lenses to sleep in, you should not be affected by any itching that you may experience during the day.

How safe are these lenses?

In our experience, these lenses are safer than standard lenses.  This is related to the lenses being worn fewer hours per week, maybe 42 hrs compared with 77 hrs for normal lenses. More unscheduled appointments are made by normal lenses wearers who sleep in lenses compared to Ortho K lenses.

What about bifocal correction?

My oldest wearer of Ortho K lenses is in her 60’s and over 40’s are regularly fitted with Ortho K lenses, so bifocal or varifocal spectacle wearers can wear Ortho K lenses. Individual assessment will provide a reliable indication of likely success.

Why not have laser surgery?

Laser surgery is not suitable for everyone. Approximately, one third of candidates are excluded due to dry eyes. As a medical procedure,  laser surgery is not without its complications: when things go wrong, the effects may not be reversible.  Ortho K is completely reversible with 99% normality restored within 5 days of stopping lens wear.

Are contact lenses hard to put in and take off?

Applying and removing contacts takes a little practice and, sometimes, patience. We don’t expect everyone to master it in an instant so you shouldn’t worry about coming back a second time.

What are Ortho K lenses?

Ortho K (or orthokeratology, to give its full name) uses specially designed rigid gas-permeable (RGP) contact lenses to subtly alter the front of the eye (the cornea) during sleep. The effect is accelerated when worn overnight and removed in the morning. They eliminate the need for spectacles or contact lenses during the day.

What about for children?

Lots of studies have demonstrated that children benefit from a confidence boost in not wearing glasses. They are also better for sports activities – no having to sit out PE at school. Research also demonstrates that Ortho K lenses have a great benefit in helping to stop, or slow, shortsight progressing. Major manufacturers are spending millions developing better designs to expand the market for these lenses.

Do children find it difficult to learn to use them?

Various studies show  that children often adapt to contact lenses better than adults. This is put down to the fact that they more readily follow instruction. Adults often think about the process too much, over complicating it which results in taking longer to adapt. Children may need a little support from parents initially but often it is confined to stepping back and letting them get on.


I have dry eyes. Can I wear Ortho K lenses?

In many instances of dry eyes, Ortho K  lenses can be worn successfully. We would attempt to address the underlying causes of the dry eye, as part of the treatment regime ( in about 70% of dry eye cases, eyelid problems contribute to the dry eye. Improving the eyelid condition, alleviates some or all of the dry eye.  It may still be necessary to use some eye drops but appropriate advice will be given.)

How often are lenses changed?

At the Ortho K Clinic, lenses typically are changed annually. This routine works very well for the majority of wearers. Where more frequent replacement is advised, that frequency is tailored to the individual and can be six, eight or nine monthly.
Changing lenses more frequently increasing the costs involved. Frequency of lens change is often dictated by manufacturer’s fitting system and changing lenses six monthly is commonly advised.
Where appropriate for the health of the eyes, annual replacement is the most economic for users.

How easy are they to look after?

For the majority of wearers, a simple multipurpose gas permeable lens solution is all that is required. At the Ortho K Clinic, we usually advise an additional ‘EASYclean’  intensive cleaner at least monthly. Very straightforward and very effective.
Some wearers like to use EASYclean all the time. This is down to personal preference but does add a little to the monthly cost.

Can I store my lenses in water?

No. You should never allow tap water to come in contact with your lenses or storage case. Hands should be dried thoroughly after washing before handling your lenses. Eyes should be kept closed if lenses are worn in the shower.

How can I check my eyes for problems with my lenses?

If in doubt about your eyes you need to ask three questions: how do my eyes feel, how do my eyes look,  do I see well (no unusual blurring with either eye)? If you can’t give a ‘normal’  answer to each of these, you should consult your eye care practitioner.

Can my lens go round the back of my eye?

No. There is a clear membrane (the conjunctiva) that covers the white of the eye and folds back onto the upper and lower lid to prevent lenses or foreign bodies getting behind the eye.

How much do Ortho K lenses cost?

Once fitted they are less expensive than the best daily disposable lenses. We offer inclusive pricing for follow up appointments, emergency appointments and care products so you never have an excuse not to seek advice when needed.

Will I still need glasses?

There will always be occasions when you can’t wear your Ortho k lenses eg during illness. It is good to keep any spectacles you used pre-Ortho k fitting as the correcting effect will largely disappear over about 4 days. When you resume lens wear, the correcting effect will return very quickly.

Contact Colin direct with any questions about Ortho K

Testimonials from recent Clients

It is brilliant not having to consider glasses and being able to see in the gym in the mornings. Great going out in the evenings and not having to contend with contact lenses which can became uncomfortable because of dryness and made my eyes tired.

They are beneficial and I would definitely reco…