What is Corneal Refractive Therapy?

woman holding contact lens

What is Corneal Refractive Therapy?


Corneal Refractive Therapy, often referred to as CRT for short, is a painless, non-invasive and straightforward treatment that can be used to help patients to see clearly the next day, without the need for glasses or laser vision correction surgery. It has also been used to slow or even halt the progress of myopia – the most common refractive eye condition in the world. Here’s what you need to know about CRT, including how to identify is you are a suitable candidate for the treatment.


Refractive eye errors

To understand how CRT works, it’s first necessary to understand how we see and how refractive errors occur. Refractive errors get their name because they are caused by a problem with the way that light is refracted by the eyes. Refraction is an essential part of vision and occurs when light hits the cornea which is the front, clear dome covering the eye. The cornea refracts the light so that it passes through the eyes and hits an area of light sensitive cells at the back called the retina. The retina converts the light into a message that is sent up to the brain to be interpreted into what we see. In patients with refractive errors, the cornea doesn’t refract the light directly onto the retina and is instead focused in front or behind it. This causes the message to be sent up to the brain to be jumbled, resulting in blurred vision.


How does Corneal Refractive Therapy work?

Corneal Refractive Therapy works by changing the shape of the cornea so that it is able to refract the light correctly onto the retina and the patient can enjoy clear vision. This is achieved using special contact lenses, which are designed specifically for your eyes and which are worn overnight. While you sleep, the slight pressure that they place onto the eyes, combined with tear film flow, helps to reshape the cornea. However, the cornea is able to retain this shape for some time after the lenses are removed. CRT is progressive, meaning that you need to wear the lenses overnight consistently to achieve the optimal result. You may be able to see an improvement in your vision for a few hours after just one session of wearing them, but your vision will quickly deteriorate as your eye loses the new shape. However, with consistent use, at optimal level patients may be able to achieve and maintain clear vision for as long as 48 hours at a time without glasses or contact lenses. CRT isn’t permanent, meaning that if you cease treatment, your vision will return to normal fairly quickly.


Am I a suitable candidate for Corneal Refractive Therapy?

You may be a suitable 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 in generally good health




If you are interested in finding out more about Corneal Refractive Therapy in Wichita Falls, TX, don’t hesitate to contact our expert eyecare team today at Clarke EyeCare Center at (940) 905-0700.