What is Corneal Refractive Therapy?

Corneal refractive therapy (CRT), also known as Ortho-K (Orthokeratology), is a simple, painless treatment for refractive eye errors like myopia and has two core benefits. First, it can be used to help patients see clearly during the day without using glasses or contact lenses, giving them the freedom and flexibility that they need to live life to the fullest. Second, CRT has been shown to help slow the progression of myopia, keeping prescriptions under control and potentially reducing the likelihood of patients developing serious eye health problems associated with high myopia in the future. 

CRT involves the use of specially designed contacts that you wear to bed at night. As you sleep, the lenses apply gentle pressure that reshapes your corneas into your ideal vision prescription. Upon awakening, simply remove the lenses and enjoy the entire day with clear vision without glasses or contact lenses. Some patients can see clearly for only a few hours, but some can see clearly for up to two days after wearing them for just one night. But with higher prescriptions, it is less likely that patients will be able to achieve functional vision without contacts or glasses.  CRT is also NOT A PERMANENT CORRECTION OF VISION, but a temporary correction so if you stop wearing the lenses, your vision will gradually return back to normal over the course of a few days.  

Another key benefit of CRT is that it can actually help to slow the progression of myopia. Most people who are nearsighted find that their eyesight gets progressively worse as they get older. This deterioration may not be rapid, but it can end in patients requiring high prescriptions. Studies have found that patients who have high myopia are more likely to develop serious eye problems in the future, including myopic degeneration and detached retina. Regular use of your corneal refractive therapy lenses could help keep your prescription stable and lower your risk of developing these problems. 

The idea for CRT started in the late 1950's when eye doctors noticed that nearsighted patients who wore hard contact lenses sometimes experienced a temporary improvement in their vision when they removed their contact lenses.  It happened because the contact lenses temporarily changed the shape of the cornea.  The cornea plays a critical role in how light is bent in the eyes and how clear the images are projected onto the retina.  The cornea is very malleable, meaning that it can mold into a different shape for a short period of time. This discovery led to the development of corneal refractive therapy, also known as orthokeratology or Ortho-K.

Here’s everything that you need to know about corneal refractive therapy and what it means for you. 
 

Understanding Refractive Vision Problems

Refractive eye problems like nearsightedness, farsightedness and astigmatism are extremely common. Patients with myopia (nearsightedness) can see nearby objects clearly, but objects further away become progressively more blurred.  Refractive errors occur when the combination of the shape of the cornea (the front surface of the eye), the lens and the length of the back of the eye together impair the light-bending and focusing process in your eyes. The light ends up focusing in the wrong place and the image projected onto the retina and then passed on to the brain, is blurred.
 

Am I a Candidate for Corneal Refractive Therapy?

You may be a candidate for corneal refractive therapy if you:

• Have a myopia prescription within specific parameters

• Have a prescription for hyperopia, presbyopia or astigmatism within specific parameters

• Have stable vision, which means that your prescription hasn’t changed during the last two years

• Are not a suitable candidate for laser vision correction

• Have a job that makes it impractical or unsafe to wear glasses or contact lenses

• Enjoy hobbies that make it impractical or unsafe to wear glasses or contact lenses

• Have healthy eyes and are generally in good health

​How Long Does It Take?

Once you receive your custom CRT/Ortho-K contact lenses, it will take anywhere from one to four weeks to fully see all the benefits to your vision that they will provide. However, some of our patients find that their vision is improved after only wearing their lenses for a single night!  During the first few days, you may also still need to wear temporary prescription glasses to see clearly enough to drive or get through your normal day, but that is generally quickly resolved. Also, some patients experience some mild discomfort for the first few nights, but as the eyes adjust to sleeping in the contact lenses, they should no longer be bothered by the feel of the lenses. Then as vision changes, new custom lenses will be prescribed to increase the changes in vision, so the process could take several months.

Is the Procedure Safe? Orthokeratology was approved by the Food and Drug Administration (FDA) in 2002. The procedure is considered safe, effective, and reversible. However, there are some side effects associated with Ortho-K. Most of these side effects are a result of improper cleaning of the lenses that can lead to minor infections and irritation.  Corneal irritation and scarring can also occur so it is imperative to keep your follow up appointments.

For more information, please set up a consultation with Dr. Kubota today.