Ortho-K (CRT)

What is ortho K/ Corneal Refractive Therapy?

Orthokeratology is a general term describing the treatment process whereby the curvature of the cornea is reshaped to allow you see clearly during the day. Corneal Refractive Therapy CRT is a branded term for orthokeratology by Paragon. There are also similar terms coined by different lens manufactures, such `OK’ lens.

CRT treatment lenses are worn at night while you are asleep. You remove the lenses in the morning and are able to see clearly throughout the day without any other vision correction.

Is CRT safe?

Older generations of orthokeratology lenses were not as effective and had some safety issues. Recent advances in computerized corneal mapping, computerized manufacturing, and oxygen permeable contact lens materials allowed the development of new generation of orthokeratology/CRT lenses that is much safer and effective than their older counter parts. Paragon CRT is the first to earn FDA approval for nighttime Corneal Refractive Therapy.

Are there any risks involved with wearing Paragon CRT?

Yes, like wearing any types of contact lenses, there is a small risk involved. Eyes can get infected if CRT is not worn and cared for properly. However, this risk is no greater than any other contact lenses. There were no serious adverse events reported in the Paragon CRT FDA clinical study.

Is Corneal Refractive Therapy Permanent?

No. It’s temporary. If you stop wearing the lenses regularly while you sleep, your vision will return to its original state in as little as 72 hours.

How Does CRT control myopia?

CRT lenses reshape your cornea in a way that it allows the image to be focused on the center of the retina and slightly in front of the retina in the periphery of the back of the eye. This slight defocusing in the peripheral retina tends to slow down myopia growth. Myopic people wearing regular glasses have peripheral images focused behind the retina, which promotes myopia development.

Who can wear Paragon CRT?

Paragon CRT treats nearsightedness (myopia up to –6.00 diopters) with or without minor astigmatism (up to –1.75 diopters). And because there are no age restrictions on Paragon CRT, it may be the perfect option for any member of the family including active adolescents. The doctor will provide more information about Paragon CRT and if it is right for you.

How long does it take to reach good vision?

It depends on your prescription and individual eye physiology. Clear vision can be achieved as fast as 2-4 weeks.

What do I do to see adequately before my CRT treatment reaches its full effect?

It’s important to understand that for a time after you have begun treatment, but before sufficient treatment is realized, your old glasses or contacts will no longer be the appropriate prescription. It may involve re-insertion of your Paragon CRT lenses for part of the day or some use of temporary soft lenses in different prescriptions. The doctor will discuss your options for visual correction during that period of time.

Can I see with my Paragon CRT lenses in?

Yes. One of the great features of the Paragon CRT lens is that if you get up in the middle of the night, you will be able to see perfectly. You will enjoy great vision with your Paragon CRT lenses on or off.

How often will I have to replace my Paragon CRT lenses?

Generally speaking the Paragon CRT lenses will have to be replaced annually. However, depending on factors such as protein buildup, how well the lenses are taken care of, etc., the lenses may have to be replaced more or less frequently.

How do I care for my Paragon CRT lenses?

Your lenses should be chemically disinfected after every use (not heat). An enzyme protein removal may be performed periodically. We will instruct you about which care system is best for you.

How much does Corneal Refractive Therapy with Paragon CRT cost?

For the first year, there is an initial treatment fee. CRT treatment cost can vary according to your prescription. We will give you an estimate after we evaluate your eyes. For subsequent years, there is an annual evaluation and CRT lens supply cost.