Orthokeratology: Days Without Lenses

Do your eye lenses give you complications for all the day-time? Are you fed up wearing those nasty glasses? And, you cant even have a surgery for that, because of your age!.. Orthokeratology, or ortho-k can be proved a panacea for all your problems. Imagine, how it would feel when, you get up one morning and find your vision all corrected! No, it’s neither a fairy tell nor a farfetched idea. Orthokeratology is all set to turn your  dreams into a reality if you are suffering from nearsightedness.

First you will have to visit the doctor who’ll begin the process by measuring the curvatures of your corneas by the method called corneal topography. There is no need to fear, at all, because it’s a completely painless procedure and, it’ll be finished in a minute. The topography will provide the map of eye’s surface and the doctor might order lenses for you.

For your information, ortho-k is not a complete lenseless phenomenon. But the difference is, here, you will be advised to wear lenses while you sleep and, in some cases, even during some part of the day-time. You don’t have to bother wearing it for the whole day.

Before you start wearing those night lenses, the doctor will prescribe you a series of temporary lenses which, you will have to wear for a period of time, before reaching a desired prescription. Ortho-k is all about reshaping the surface of your eyes to that of the people of normal vision. When you sleep with the special contact lenses on, it gently reshape the surface of your eyes so that you could see clearly even after removing the lenses. The effect is temporary as it can last one or two days–you’ll have to wear the lenses each night.

As we know by now, ortho-k is only applicable for those, who are myopic or short-sighted. In this case, the light rays coming from distant objects do not focus on the retina and, do not make any clear images. The reason behind the defect is, either the cornea is too curved, or the eyeball is too long. Overnight lenses are gas permeable lenses made up of a special hard type of plastic. They gently press on the cornea and, reduce its curvature so that the focal length increases, refocusing the light directly on retina. It also shortens the eyeball with quite an efficacy. Doctors believe that the best candidate for such technology are people who have low amounts of myopia, about 4 diopters or less, but people with slightly higher amount of this, say, 5 or 6 diopters are also found to be benefitting.

Ortho-k is not a completely new phenomenon. It has existed for centuries. It’s believed that the chinese slept with small weights or sandbags, on their eyelids, to counter short-sightedness. However, it was not a very reliable method as, they never knew whether their lenses were going to work in the morning. After the development of the technique, corneal topography, the process has become far more accurate and easier. It has been practiced by some eye doctors for decades, only it had a limited appeal, because of the mixed results of the experiment.

The lenses are not suitable for people who are suffering from hypermetropia, because, their corneas are too flat and further flattening will only worsen the case.

There are many advantages of ortho-k over other techniques to correct your eye vision. First, as you are wearing the lenses while you are sleeping, you won’t have to grope for your specs, in case you wake up in the night and need to see. Second, you don’t have to fear the exposure to smoke, dust or water as you are not going to wear them throughout the day. It’s particularly recommended for those who live a very active life like sportspersons or journalists. Third, the people who want to wear the GP lenses (Gas Permeable lenses) but face difficulty wearing it, given the sensation and awareness resulting from the direct interaction of the eyelid with the edge of the lenses during blinking, can also wear it because during the sleep, blinking is not required. Fourth, it’s believed to be beneficial for those who have the problem of dry eyes.

Similar results, however, can be achieved throuh LASIK (laser-assisted in situ keratomileusis), a type of refractive surgery to correct vision. But for the adoloscents and teens, who are not eligible for LASIK, ortho-k becomes a lucrative option. Ortho-k can be performed on the eyes of any age as long as they are healthy. Besides, LASIK tends to worsen the case of dry eyes which is not the case with ortho-k.

Among a spate of advantages, you can also experience some side effects. During the time when your eyes are being reshaped, you’ll have halos and glare that’ll be reduced with time, but it’ll never go away. It’s also the problem with LASIK patients with large pupil. Secondly, there are some concerns about corneal infections in young people who went through ortho-k, so it’s advisable for them to go to an experienced eye care practitioner, who’s good in treating this age group. Thirdly, unlike LASIK, ortho-k is reversible. If you decide to have a surgery after you have gone through ortho-k, you can always do that after you corneas revert to their natural shape.

All contact lenses come with a set of side effects some of them very dangerous for the eyes. Certainly, ortho-k overnight lenses have an edge over them. We only hope this method to evolve further, so that it could become cost-effective and, easily accessible to the poor. Witnessing such developments, we can only hope a better and inclusive vision for the world.

Sangya Supatra

[Image courtesy: http://www.eyedoctorguide.com/images/orthokeratology_ortho-k_lenses.jpg]