Corneal Refractive Therapy (CRT)

Are you frustrated with the eyesight you were born with? Do you feel like your vision is getting worse with time? Corneal Refractive Therapy (CRT), or Orthokeratology, is a non-surgical way to improve eyesight by using special contact lenses. Just like orthodontists use braces and retainers to restructure the mouth, ophthalmologists utilize CRT to gradually improve your eyesight. Get better vision without needing eyeglasses or contacts every day!

How Corneal Refractive Therapy Works

How Corneal Refractive Therapy Works Therapeutic contact lenses are designed to gradually change the shape of the cornea to reduce moderate to severe nearsightedness. Unlike normal contact lenses, CRT contact lenses are not designed to match the cornea’s existing shape, but instead, apply gentle pressure to the center of the cornea. That pressure corrects extreme roundedness of the cornea, the cause of nearsightedness. CRT lenses are usually only worn overnight.

Who can benefit? CRT is an excellent option for

  • individuals with nearsighted vision
  • individuals with astigmatism
  • both adults and children


CRT patients may start to see changes and improvements within hours or days of using their lenses. Significant improvements are usually noticed within 3 to 6 months. Once maximum results are achieved, retainer lenses are work periodically to maintain the new corneal shape. CRT is a corrective procedure. The frequency that patients wear their retainer lenses depends upon their unique eye health. Usually, it’s a short period of daily or weekly wearing time. Patients who do not follow their prescribed schedule of maintenance may have their previous vision return.