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Corneal Refractive Therapy (CRT)

Correct your vision while you sleep with safe, non-surgical Paragon CRT therapeutic lenses.

Enjoy great vision 24 hours a day, without the hassles of glasses and daytime contacts with this process. A specialty of Dr. Haak’s, CRT has become popular—particularly with younger children.


What is CRT?

Corneal Refractive Therapy (also called orthokeratology or ortho-k for short) is a non-surgical process clinically developed to reshape the cornea while you sleep.

Is Paragon CRT new?

While contact lens corneal reshaping is not a new concept, Paragon CRT is the one corneal reshaping modality with proven safety and efficacy and the first to earn FDA approval for nighttime Corneal Refractive Therapy.