By Michael Hutton 

Ortho-k lenses cost  much less than most people think given that they provide all the benefits of laser surgery - but without the risks of the surgery. Orthokeratology is a relatively new treatment for short-sightedness - otherwise known by the technical term ‘myopia' - and is becoming of increasing interest globally given that it can be used by people of all ages from 6 to 60. It is a particularly attractive option for dry eye and allergy sufferers, sports participants and children, with the latter group enjoying the additional important benefit of ‘myopia control'. This means that once a child starts wearing ortho-k lenses, their short-sightedness will not continue to worsen as would be the case if glasses or conventional contact lenses are worn instead.

So what does orthokeratology involve? Well, it is a straightforward treatment where precise and highly detailed maps of the eyes are created using a special computerised device called a topographer. These maps are then used to design and manufacture small bespoke contact lenses which are only worn while sleeping. This is the unique feature of orthokeratology - once the lenses are removed each morning, the wearer has perfect natural vision which lasts all day long until the lenses are reinserted at night. And if you wake at night with the lenses inserted, you still see perfectly because the lenses are fully optically corrected - you can see with them in or out of your eyes. Such a great way of dealing with short-sightedness and the good news is that ortho-k lenses cost  less than a daily cappuccino.

For those who think it still sounds like a case of ‘smoke and mirrors', you may be surprised to know there is a perfectly solid science behind orthokeratology. Whilst sleeping, the lenses gently reshape the surface of the eye using the mild pressure of closed eyelids to ensure that light entering the eyes focuses directly on the retina rather than in front of it which is why distant objects look blurry to short-sighted people. The effect is like muscle memory and last for over 24 hours which is why the lenses need to be worn every night to maintain perfect vision all day after they are removed. So you can swim, play rugby and forget about dry irritable eyes to name but three benefits - and see to the far end of the coffee shop yet ortho-k lenses cost  less than the contents of the cup in front of you.