If you’ve dreamed of waking up in the morning able to see clearly, but you don’t want or aren’t a candidate for surgery to correct your nearsightedness, orthokeratology might be for you. Also known as ortho-k, orthokeratology is a process that uses special, semi-rigid gas permeable contact lenses to change the shape of your eye while you sleep so you can see more clearly when you are awake.
Focus on the Eye
When light enters the eye it passes through a clear layer on the front of the eye called the cornea, then travels through the pupil and lens to the retina, which is the lining on the inside of the back of the eye. The cornea and the lens both work to focus the light on the retina. When the light doesn’t focus correctly, our vision is blurry. When we can see near objects, but not far away objects, we are nearsighted or myopic. This is usually corrected using either eyeglasses or contact lenses to help the eye focus clearly.
How Ortho-k Works
LASIK surgery corrects nearsightedness by using a laser to change the shape of the cornea so the eye can focus more clearly. Ortho-k uses the same theory to correct vision by reshaping the cornea. But rather than using a laser for a permanent change, ortho-k uses specially shaped contact lenses to flatten the surface of the cornea without surgery. New developments in night-wear contacts now allow these special lenses to do their work overnight. The affects are not permanent, but in many cases wearing the lens each night while you sleep will change the shape of your eye enough to give you clear vision through the next day.
Ortho-k is not a quick fix. Each pair of contacts can only make a small change to your vision. Depending on how nearsighted you are you may have to go through several pair of contact lenses to step up to the best level of vision possible. Some people may have clear vision in just a few weeks while others require several months before their eyes stabilize after wearing the lenses each night.
Ortho-k is a temporary vision solution, which means you must continue to wear the lenses every night to maintain clear vision once your eyes have stabilized. This process is similar to wearing a dental retainer after braces are removed. If you don’t wear the lenses, your eyes will gradually return to close to their original shape.
Who Can Benefit from Ortho-k?
Ortho-k may be a good alternative for children and teenagers who are not eligible for surgery such as LASIK. People who live in dry, dusty climates or who play sports can also benefit from having clear vision without lenses during the time they are awake. If you chose to have surgery for permanent vision correction, you may need to stop wearing ortho-k lenses for several months before the surgery to allow your eyes to return to their natural shape.
Ortho-k is not a new procedure and a number of companies offer lenses for this procedure. Night-wear lenses are relatively new and few have been approved by the FDA at this time. Nightwear lenses that are FDA-approved include CRT (corneal refractive therapy) lenses from Paragon Vision Sciences and VST (vision shaping treatment) lenses from Bausch & Lomb. The FDA requires special training for doctors prescribing ortho-k lenses. Be sure to talk to your eye care professional about whether ortho-k is right for you and to find out which lenses they are approved to prescribe and fit.
Sources:
All About Vision
Ortho-k Network
U.S. Food & Drug Administration
Paragon CRT
Bausch & Lomb