Corneal Refractive Therapy

CRT Contact Lenses

Have you ever thought about laser eye surgery but then decided that it was too expensive? Or perhaps you were you just too squeamish about the surgery? Or you were not an appropriate candidate for laser eye surgery? Well then, Corneal Refractive Therapy (CRT) may just be your ticket to visual freedom! It's a non-surgical alternative to laser treatment, and although it can be more costly than regular contact lenses, it's substantially more affordable than laser eye surgery. And unlike laser surgery, corneal refractive therapy is reversible.

CRT is basically a system where a custom-made contact lens is made specifically for your eye. While it's on your eye, it gently reshapes the corneal surface. You put these special contact lenses in at night just before you go to bed. Then when you wake up in the morning you take them out and you are able to see clearly! The length of time that a person is able to have clear vision without having to put the contact lenses back in varies; you may have an entire day of clear vision, or you may need to put the lenses in towards the end of your day. The effects may last even longer than a day, but it's important to put the lenses in each night to make sure your lenses don't regress back to their initial prescription.

How Does it Work?

CRT is a process whereby the cornea is gently flattened by a specially constructed rigid gas permeable contact lens. This flattening results in a gradual reduction in the amount of prescription needed for you to see clearly. However, you won't notice this gradual reduction because as long as you are wearing the contact lenses you can see clearly. When you take the lenses out in the morning after wearing them all night, you will have vision that is just as clear.

What to expect at the Optometrist's office

If you're interested in CRT then the next step is to see your optometrist. He or she will determine if you are a good candidate, if so you will be fitted with CRT lenses. When you are at your optometrist's office the most important instrument for determining your candidacy is called a corneal topographer. This machine essentially maps out the surface of your cornea, and works according to the same principle as orienteering maps. Each color represents a different elevation on your corneal surface. It's this map that the doctor will use to determine which lenses are right for you. It's also the way in which your doctor is able to monitor the progress and effectiveness of your lenses.

Who is a good candidate?

Anyone with moderate (ie. about -6.00 D) to low amount of nearsightedness (myopia) is a good candidate for CRT. Small amounts of astigmatism can also be corrected using CRT.

Will it hurt? Not at all. You may initially be aware that the contact lens is on your eye, but this will go away with time.

Who is not a good candidate?

CRT is not yet available for hyperopes (anyone whose prescription is preceded by a + sign, for example +1.50 D). Also, since CRT requires the wearing of contact lenses, any disease or condition that does not allow for contact lens wear is also not recommended for CRT.

How much does it cost?

CRT lenses are not cheap. However, they hold the amazing capability of reshaping your cornea so that you are able to have clear vision even without the bother of contact lenses or glasses during the day. On average, each lens will cost about $500 to $750. The cost varies with practitioner as well as the number of lens changes you may need. Generally the lenses are replaced annually, but this does vary among people according to such characteristics as protein build-up and cleaning regimes.

What about Ortho-K?

Perhaps you've heard of the term Ortho-K, or orthokeratology. This is a very similar technique, using the same principle about gently reshaping the corneal surface. The difference, however, is in the lenses used and the FDA approval status. CRT lenses use only one brand of specially-made contact lenses by a company called Paragon. This company holds proprietary rights and it is FDA approved. Ortho-K has been around much longer and is practiced with a variety of different lenses. Only one lens has been FDA-approved for overnight wear.