Orthokeratology

Orthokeratology, or Ortho-k, is a technique fitting a rigid contact lens that you only wear at night while you sleep. The shape of the lens slightly and gently changes the shape of the cornea, or the front surface of the eye, so that when you wake up and remove the lens, you can see during the day without glasses or contact lenses. You need to wear that retainer lens every night, or your eye goes back to its usual shape and your prescription returns. The process works on a wide range of prescriptions, but is most straightforward on people who are mild to moderately short-sighted, i.e. they can see up close, but not in the distance. The lenses are also designed so that you can see while wearing them, so although they do their best work while you sleep, if you do get up in the middle of the night, your vision is still ok!

Depending on your prescription, ortho-k can take a couple of days, or up to a couple of weeks, to correct your vision. During that time you might need some temporary glasses in an “in-between” power. If you stop wearing the ortho-k lenses your eyes go through the reverse process, with your prescription slowly going back to what it was before. This is sometimes necessary if you go on holidays and don’t want to wear your overnight lenses, or if you get an eye infection or the flu and can’t wear them, or even sometimes if we want to start from scratch and get new lenses. Your optometrist will work with you to make sure you can see during each stage of your ortho-k journey.

Contrary to what you might think, these rigid lenses are comfortable, because you’re not awake and blinking, your eyelids don’t constantly move over the lens and remind you it’s there. This makes ortho-k a great option for people who find contact lenses irritating to wear during the day, or people who have jobs or hobbies which might dislodge a normal daytime contact lens. Ortho-k has also been found to reduce or sometimes stop myopia (short-sightedness) from getting worse as the eye develops, and with proper care and supervision can be suitable to use in children to reduce the strength of the glasses they will need as an adult, and also reduce the risk of conditions that are more likely in myopes, like retinal detachment, glaucoma, cataracts and macular degeneration. The safety of ortho-k lenses is much the same as other forms of contact lens, you need to follow basic care and hygiene procedures, which will be clearly explained during the fitting, and in return you get clear, comfortable vision.

Ortho-k gives you a change in lifestyle, eliminating the need for vision correction during the day, while being safe, non-surgical, and completely reversible. Having great vision while being free from glasses or daytime contacts is ideal for sports and swimming, smoky or dusty environments, people who have dry eyes at the end of a workday, or children and teenagers whose parents are short-sighted and want to reduce the worsening of their own prescription.