Orthokeratology
What Is Ortho-K?
Orthokeratology (ortho-k) is the fitting of specially designed gas permeable hard contact lenses that you wear overnight. While you are asleep, the lenses gently reshape the front surface of your eye (cornea) so you can see clearly the following day after you remove the lenses when you wake up.
Ortho-k lenses are prescribed for two purposes:
- To correct refractive errors (primarily nearsightedness, but also astigmatism and hyperopia). In some cases, ortho-k also is used to correct presbyopia.
- To slow the progression of childhood myopia. (Read more about myopia control.)
Ortho-k lenses are also called “corneal reshaping contact lenses” or “overnight contact lenses to correct or control myopia.” Only highly “breathable” GP lenses that have been approved for overnight wear should be used for orthokeratology. Speak to your eye care professional to learn more.
How Long Does The Ortho-K Effect Last?
You should be able to see acceptably well without glasses or contact lenses for a day or two, sometimes longer. For best results, you should wear the ortho-k lenses every night. Consult with your Optometrist to achieve the best performance when trying Ortho-K.
Which Vision Problems Can Ortho-K Correct?
Orthokeratology is most frequently used to temporarily correct myopia (nearsightedness). Generally, ortho-k can correct upwards of -6.00 diopters (D) of myopia.
Ortho-k also can correct lesser degrees of astigmatism, hyperopia and presbyopia.
The type and amount of refractive error that can be effectively managed with orthokeratology differ on a case-by-case basis. Your Optometrist will be able to give you more specific guidance after examining your eyes.
Who Is A Good Candidate for Orthokeratology?
Most people with mild to moderate myopia (with or without mild astigmatism) are good candidates for ortho-k. The corneal reshaping effect is temporary so little risk is involved, and you can discontinue wearing the lenses at any time — provided you are willing to start wearing glasses or contacts again when your myopia returns!
Children and young adults who want to be glasses-free but are too young for LASIK or are not good candidates for refractive surgery for other reasons (dry eyes, for example) often are good candidates for ortho-k. People who participate in contact sports or work in dusty environments that can pose problems for contact lens wear also can be good candidates.
Who Fits Ortho-K Lenses?
Optometrists perform most orthokeratology lens fitting. But ophthalmologists also perform ortho-k fittings. In some cases, ortho-k may be performed by an Optician or contact lens technician under the supervision of an optometrist or ophthalmologist.
It is important to know that orthokeratology is a very specialized type of contact lens fitting, and not all Optometrist who fit contact lenses also fit ortho-k lenses. If orthokeratology interests you, seek the services of an Optometrist who specializes in fitting these lenses.
What Results Can You Expect From Ortho-K?
Eye care practitioners usually aim for 20/20 vision after ortho-k, but 20/40 vision (the legal minimum for driving in most of the United States) often is considered an acceptable outcome.
In the FDA clinical study for approval of Paragon CRT lenses, 93 percent of patients achieved 20/32 vision or better, and 67 percent achieved 20/20 or better. In the clinical study for FDA approval of one VST design, about 95 percent achieved 20/40 or better, and 73 percent achieved 20/20 or better. Both studies followed patients for at least nine months.
What To Expect When You Begin Ortho-K
The Optometrist will begin by measuring the curvatures of your corneas using an instrument called a corneal topographer— a painless procedure that produces a topographical map of your eye’s surface.
Your Optometrist might use an in-office inventory of lenses for fitting your eyes with ortho-k lenses the same day corneal topography measurements are taken, or he or she may order custom ortho-k lenses for fitting at a later date.
You may need a series of temporary lenses to see properly until you reach the desired prescription. In most cases, up to three pairs of lenses are required to achieve the maximum vision correction effect.
When you begin to wear ortho-k lenses, you will likely have some awareness of the lenses on your eyes until you fall asleep. With time, the lenses typically become more comfortable immediately upon insertion.
How Long Does It Take For Maximum Ortho-K Effect?
This depends on many factors, especially the amount of nearsightedness (and possibly astigmatism) you have when you begin the ortho-k process. Some people can have excellent vision after a day or two of overnight ortho-k. But for higher prescriptions it can take two weeks or longer for maximum correction.
Until your eyes are fully corrected, you might notice blurred vision and glare and halos around lights. In some cases, you may need to wear glasses (with a lesser prescription than you originally had) during the ortho-k process. Also, in some cases, mild glare and halos might persist even after maximum ortho-k correction.
How Much Does Ortho-K Cost?
Fitting ortho-k lenses is a more time-consuming process and requires more expertise than fitting regular contact lenses. It requires a series of office visits and potentially multiple sets of lenses. Each eye care practitioner determines his or her own fees for orthokeratology, based in part on the doctor’s level of expertise, time required and lens costs.
The cost of ortho-k, including follow-up care associated with fitting the lenses, can vary significantly depending on the type and degree of your refractive error and whether you are choosing ortho-k lenses for long-term myopia control in addition to the temporary correction of existing myopia. Costs also can vary based on the region of the country, urban vs. rural settings, and the type of practice where you have the fitting and treatment performed.
Ortho-k prices generally range from $1,000 to $3,000 (for both eyes), making the procedure roughly half the cost of LASIK. But particularly difficult cases of ortho-k can cost as much as $4,000. There are additional costs for replacement ortho-k lenses, lens care solutions and follow-up exams, which can total about $300 to $500 per year.
Normally, orthokeratology is not covered completely by vision care insurance plans, but a portion of the fees may be covered by some plans. Please consult with your eye care professional to learn more about all costs involved.