Eye health resource
How Overnight Contact Lenses Work to Control Myopia
Ortho-K lenses are worn during sleep to temporarily reshape the cornea and provide daytime vision without lenses. In children, Ortho-K may also slow myopia progression.
Reviewed for accuracy by Justin Bazan, OD on .
Orthokeratology (Ortho-K) uses specially designed rigid contact lenses worn during sleep to temporarily reshape the front surface of the cornea. The lenses are removed in the morning, and many patients can see clearly during the day without glasses or daytime contact lenses.
In children with progressive myopia, Ortho-K can also be one option in a broader myopia-management plan. Its daytime vision effect and its myopia-control purpose are related but not identical goals.
What Is Myopia?
Myopia, or nearsightedness, occurs when light focuses in front of the retina rather than directly on it. This commonly happens because the eye grows too long from front to back.
Myopia usually begins in childhood, often between about ages 6 and 14, and commonly progresses into the teenage years or early adulthood. Higher levels of myopia are associated with greater lifetime risk of retinal detachment, glaucoma, myopic macular degeneration, and some other eye conditions.
How Does Ortho-K Improve Daytime Vision?
An Ortho-K lens is designed from detailed measurements of the corneal shape. During overnight wear, the lens and the tear layer beneath it redistribute epithelial cells across the corneal surface, producing a controlled temporary change in curvature.
After the lens is removed in the morning, that altered corneal shape reduces the eye's myopic refractive error. The effect is temporary. If Ortho-K wear stops, the cornea gradually returns toward its original shape and the myopia correction wears off.
Does Ortho-K Permanently Cure Myopia?
No. Ortho-K does not permanently eliminate the underlying refractive tendency or permanently shorten an elongated eye.
The corneal reshaping effect needs to be maintained on the wearing schedule prescribed by the doctor. Some patients need nightly wear; others may eventually use another maintenance schedule depending on how their eyes respond.
How Can Ortho-K Help With Myopia Progression?
In children, specially designed myopia-management lenses can change the pattern of focus on the peripheral retina. Clinical studies show that Ortho-K can reduce the rate of axial eye growth in many children compared with ordinary single-vision correction.
That does not mean every child will respond the same way or that Ortho-K completely stops myopia. The goal of myopia management is to slow progression and reduce the chance of reaching a higher final level of myopia.
What Other Myopia-Management Options Are Available?
Park Slope Eye currently uses three broad approaches when appropriate:
- Ortho-K — overnight corneal reshaping lenses.
- Low-dose atropine — prescription eye drops used off-label in the United States for myopia management.
- Soft multifocal / myopia-control contact lenses — daytime lens designs intended to provide vision correction while changing peripheral retinal focus.
Atropine's myopia-control effect should not be reduced to the old idea that it simply “relaxes the eye muscles.” The biological mechanism is more complex and is still being studied.
Who May Be a Candidate for Ortho-K?
Ortho-K can be used by selected children and adults with appropriate corneal health and refractive error. The amount of myopia and astigmatism that can be treated depends on the specific FDA-approved lens design and the patient's corneal shape.
For children, maturity and the ability of the family to follow careful lens hygiene are important considerations.
Is Sleeping in Ortho-K Lenses Safe?
Ortho-K is specifically designed and prescribed for overnight wear, but sleeping in any contact lens carries more infection risk than not wearing a lens overnight. Careful fitting, cleaning, disinfection, hand hygiene, follow-up, and avoidance of water exposure are essential.
Remove the lenses and contact an eye-care professional promptly for significant pain, redness, light sensitivity, discharge, or sudden blurred vision.
What About LASIK?
LASIK or PRK can reduce refractive error in appropriate adults by permanently reshaping corneal tissue. They do not treat progressive childhood myopia, and they do not reverse the retinal or optic-nerve risks associated with an eye that is already highly myopic and elongated.
Refractive surgery is therefore a different decision from childhood myopia management.
What Happens at an Ortho-K Evaluation?
A recent comprehensive eye examination is required so the doctor has current prescription and eye-health information. Park Slope Eye also uses a corneal topographer to map the corneal surface for specialty lens design and follow-up.
If a comprehensive examination was completed elsewhere within about three months, Park Slope Eye can generally use it as long as we receive a copy of the complete exam record. An eyeglass prescription by itself is not enough. If we do not have documentation of the recent comprehensive examination, we will need to perform one before proceeding with the Ortho-K fitting.
Is Ortho-K Right for You or Your Child?
Ortho-K can provide daytime freedom from glasses or contacts and, in appropriate children, can also be part of a plan to slow myopia progression. The best choice depends on prescription, corneal shape, age, lifestyle, myopia progression, and the family's comfort with lens care.
Book an appointment to discuss myopia management and Ortho-K at Park Slope Eye.
Originally published . Substantially updated .