Orthokeratology
What is orthokeratology?
For people that are tired of wearing contact lenses or glasses all day long and do not want to commit to vision correction surgery (i.e., LASIK, PRK, ICL, etc.), orthokeratology (ortho-k) is the ideal solution. Ortho-k is a modern, non-surgical process that involves reshaping the cornea, the front of the eye, by utilizing specialty contact lenses to provide temporary and reversible refractive error correction after lens removal.1 The gas-permeable (GP) lenses are intended to be worn overnight and provide uncorrected visual correction during waking hours. This process has gained significant popularity in correcting myopia (nearsightedness) and being used in myopia management for kids; however, it can be successful in correcting some amounts of astigmatism, hyperopia (farsightedness), and presbyopia (loss of near vision associated with age).1-3
Who are good candidates for orthokeratology?
Good potential candidates for ortho-k include children with progressive myopia, kids that struggle to keep their glasses on or are not independent enough to try soft contact lenses yet, patients that suffer from soft contact lens-related dryness or discomfort, and people with active lifestyles, such as participation in sports, where glasses or soft contact lenses are impractical. The amount of refractive error that can be corrected with ortho-k lenses varies but can correct up to ~6.00 diopters (D) of myopia and ~1.50 to 2.00 D of astigmatism.1 Although ortho-k is not commonly used to correct hyperopia or presbyopia, it has been successful in correcting up to about 1.50 to 2.00 D hyperopia and up to +2.00 D of monovision correction in patients with presbyopia.1,2 Ortho-k can also create a multifocal effect for presbyopia patients, but further research is needed to better understand this mechanism.
What does the orthokeratology process look like and where can I get fitted?
When an eyecare provider determines that a patient is a good candidate for ortho-k, they will run different tests and assessments to order the best fitting ortho-k lenses for that patient’s eyes. It may take a few different lenses to arrive at the best fit. Once the proper lens is determined, the patient wears the lens nightly. The majority of the visual correction happens during the first night of lens wear; however, it may take up to 1-2 weeks to achieve full correction.1 During this time, the provider may give the patient disposable soft contact lenses to provide visual correction during the day. Once full treatment is accomplished, the patient should be able to see well without the need for glasses or contact lenses during the day.
While ortho-k has gained popularity, not every eye care practitioner provides this specialized service, so it is important to do prior research to see which providers in your area offer orthokeratology.
How safe is orthokeratology?
Like any contact lens, ortho-k has some risk for non-serious and serious complications. Luckily, the majority of complications with ortho-k lens wear are not serious.1 Non-serious complications include eye discomfort/irritation, dryness, or blurred vision. These can be managed through the simple use of artificial tears and/or through design changes made during follow-up visits. A more serious complication that can occur is an eye infection, and if not managed and treated in a timely manner, can lead to vision loss. The risk of infection is rare for overnight ortho-k lens wear and is similar to other overnight contact lenses, which is about19-25 per 10,000 wearers.4,5 Because ortho-k involves overnight lens wear, frequent follow-ups/office visits and proper lens wear and care are recommended for long-term safety and success.
Why orthokeratology?
The most recent positive effect seen with the use of orthokeratology is slowing down the progression of myopia (nearsightedness) in children.1,3,4 With myopia/nearsightedness, the eyeball’s length (axial length) can be longer than normal and as the axial length increases, it can lead to more dependency on glasses/contact lenses or worse, visually debilitating complications. Studies have shown that orthokeratology is an effective treatment in myopia control by slowing eyeball growth.3.4
Another benefit with ortho-k that was discussed earlier is freedom from glasses or contact lenses during the daytime without the permanence of surgery. The reversible, temporary visual correction ortho-k provides can improve quality of life for many patients with myopia, astigmatism, hyperopia or presbyopia.
Contributed by: Janna Pham, OD
References
1. Vincent SJ, Cho P, Chan KY, et al. CLEAR – Orthokeratology. Contact Lens and Anterior Eye. 2021;44(2):240-269. doi:10.1016/j.clae.2021.02.003
2. Gifford P, Swarbrick HA. Refractive Changes From Hyperopic Orthokeratology Monovision in Presbyopes. Vol 90.; 2013.
3. Hiraoka T. Myopia Control With Orthokeratology: A Review. Eye Contact Lens. 2022;48(3):100-104. doi:10.1097/ICL.0000000000000867
4. Bullimore MA, Johnson LA. Overnight orthokeratology. Contact Lens and Anterior Eye. 2020;43(4):322-332. doi:10.1016/j.clae.2020.03.018
5. Liu YM, Xie P. The safety of orthokeratology – A systematic review. Eye Contact Lens. 2016;42(1):35-42. doi:10.1097/ICL.0000000000000219