Corneal Refractive Therapy (CRT)

What is CRT?

Corneal Refractive Therapy or CRT is nighttime vision correction that gives you freedom from glasses and contact lenses all day without refractive surgery. CRT utilizes a specially designed therapeutic contact lens to gently reshape the cornea while you sleep. The lenses are removed when you awake and you are able to go throughout the day without correction. This is a temporary process. If you stop wearing the lenses, your vision will return to its original state within 72 hours.

Most patients will notice great changes in their vision within just 1-2 days but it may take 7-14 days to achieve optimum visual results. During this transitional period we will provide temporary soft lenses for daytime use if needed. Because you are able to see with your Paragon CRT lenses on, you may decide to put on the lenses during the day for a short time during this transitional period.

Paragon CRT is currently designed for individuals with low to moderate nearsightedness (up to –6.00 diopters) with or without astigmatism (up to –1.75 diopters). The great thing about CRT is that there are no age restrictions. Even children can benefit from this treatment and not have to deal with lenses during the day. We usually will start fitting children into regular contact lenses around age 10 at the earliest and the same would be true for CRT. Children or teens who are active in sports, tend to forget or lose glasses or just won’t wear glasses are great candidates for CRT.

There are many people who have trouble with discomfort or dryness from wearing contact lenses during the day. Some people may not be ready for LASIK surgery or are not candidates for LASIK. CRT is a great option for these patients.

There is a small risk involved in wearing any contact lens. These may include increased risk of infection if not taken care of properly, corneal irritation and corneal swelling. In the FDA clinical study of CRT there were no serious adverse reactions

It is recommended that the lenses be replaced about once a year. The lenses are a very high oxygen permeable lens and have a very precise design. Replacing the lenses regularly will ensure the best vision possible.


Please feel free to visit paragonvision.com for more information. Or call our office for a consultation to see if you are a candidate for Paragon CRT.