Corneal Refractive Therapy with Paragon CRT®
Sleep your way to Great Vision  

Correct your vision while you sleep with safe,
non-surgical Paragon CRT therapeutic lenses, and
enjoy great vision 24 hours a day, without the hassles
of glasses and daytime contacts.
Our doctors at Eyeworks of San Mateo are trained, certified, and experienced  to
perform CRT®.  This is a specialty contact lens that not all practioners can fit.

CRT is a great non-surgical option for kids as well as adults, allowing them to see well without
glasses or contacts by day.  We have treated sucessfully kids as young as 8 years of age.
After fitting the lens, we track and follow the progress of the patient for up to 3 months out.
As a matter of fact, Dr. Gary Lai was interviewed on Channel 7 ABC with Dr. Dean Edell.
See here.

To see if you are a candidate for CRT, give us a call to schedule a complimentary consultation.
We'll tell you if you qualify or not. Upfront. Just the facts.  If you are a candidate for CRT, then you can
decide if CRT is something you like to pursue.  

On the day of consultation, be sure to bring your glasses and packaging of your contact lens if you
have them.

For more information, simply call us with any questions or visit
The following is excerpted from Paragon CRT's website for your convenience.
Corneal Refractive Therapy (CRT) is a non-surgical process clinically developed
and FDA approved to reshape the cornea while you sleep. The result is the
temporary correction of myopia with or without moderate astigmatism.

Similar in appearance to standard contact lenses, Paragon CRT therapeutic
lenses gently reshape the corneal surface during sleep.  When the Paragon CRT
lenses are removed in the morning, the treated cornea allows light to focus on the
retina. The result is clear, natural vision for all or most of your waking hours.  

Because Paragon CRT offers freedom from glasses and the hassle of wearing
contact lenses during the day, this leading-edge technology can enhance the
lifestyle of those requiring vision correction. Active individuals can freely participate
in sports without the interference of glasses or bother of contacts. Eye irritation or
dryness, sometimes associated with contact lens wear due to outside dust and
pollutants, is eliminated.   
What is CRT®
and how does
it work?
FAQ's - Frequently asked questions
How new is Paragon CRT?

Contact lens corneal reshaping is not a new concept.  Previous corneal reshaping designs were only as
successful as technology allowed.  Paragon Vision Sciences has taken the recent advancements in
computerized corneal mapping, computerized manufacturing, and oxygen permeable contact lens materials and
produced a therapeutic contact lens design that is like no other.  This has allowed Paragon CRT to become the
one corneal reshaping modality that truly stands out and the first to earn FDA approval for nighttime Corneal
Refractive Therapy.  

Is Corneal Refractive Therapy or Paragon CRT FDA approved?

Paragon CRT is the first therapeutic lens design approved by the FDA for overnight contact lens Corneal
Refractive Therapy for the temporary reduction of myopia.  Paragon Vision Sciences, the manufacturer of Paragon
CRT, received the final written approval on June 13, 2002.  The issuance of this approval is the culmination of the
most extensive clinical study to date to establish the safety and efficacy of contact lens corneal reshaping in
overnight use.

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.

Can everyone wear Paragon CRT?

Not everyone can wear Paragon CRT.  This lens is designed for individuals with low to moderate myopia
(nearsightedness up to –6.00 diopters) with or without astigmatism (up to –1.75 diopters).  Paragon CRT
therapeutic lenses are not yet available in bifocal prescriptions for presbyopia (which requires reading glasses or
bifocals).  At your doctor’s discretion you may be fitted in a monovision mode (one eye corrected for near vision
and one corrected for distance vision).  You might still need reading glasses.  However, since there are variations
in patient physiology and visual needs, the decision for CRT, at any age, can only be made after a thorough eye
exam and the recommendations of the eye care professional.  At this time, hyperopia (farsightedness) is not
correctable with CRT.

Are there age restrictions for Corneal Refractive Therapy with Paragon CRT?

No.  The FDA placed no age restrictions on candidates for Corneal Refractive Therapy with Paragon CRT.   CRT
is being successfully performed on children 12 years old and younger.  It can be a great option for children and
teens that are active in sports activities or any other extra curricular activities.

Those who are older and presbyopic (requiring reading glasses or bifocals) may still be candidates for CRT.  
They may correct their distance vision with CRT and wear near-vision reading glasses for close work.  At the
doctor’s discretion you may be fitted in a monovision mode (one eye corrected for near vision and one corrected
for distance vision).  

Visual requirements due to age or activities can only be assessed after a thorough eye exam.  Your Paragon CRT
certified eye care professional will recommend what is best for you.

How long does it take to reach good vision?

Most patients have rapid improvement in the first few days of treatment and achieve nearly their optimum vision in
10 to 14 days.

What do I do to see adequately in the period of time between when I start Corneal Refractive Therapy with
Paragon CRT and when I achieve full treatment?

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 insertion of
your Paragon CRT lenses for part of the day or some use of temporary soft lenses in different prescriptions as an
option. Your eye care practitioner will discuss your options for visual correction during that transitional period of

Are there any risks involved with wearing Paragon CRT?

There is a small risk involved when any contact lens is worn.  It is not expected that the Paragon CRT lenses for
contact lens Corneal Refractive Therapy will provide a risk that is greater than other contact lenses.  There were
no serious adverse events reported in the Paragon CRT FDA clinical study.

Can I see with my Paragon CRT lenses in?

Yes.  One of the great features of the Paragon CRT lens is that if you have to get up in the middle of the night, you
will be able to see where you are going.  Or, if during the initial treatment phase, you find you need some form of
vision correction, you can put in your Paragon CRT lenses and see clearly.

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

Generally speaking the Paragon CRT lenses will have to be replaced once a year.  However, depending on
factors such as protein build-up, how well the lenses are taken care of, etc., the lenses may have to be replaced
more frequently.

How do I care for my Paragon CRT lenses?

Your lenses should be chemically disinfected after every use (not heat).  Your eye care practitioner will instruct
you about which care system is best for you.

Is Corneal Refractive Therapy painful?

The therapy is not painful.  Initially, you may have a slight awareness of the therapeutic lens.  You will not feel the
lenses when you sleep and there is no sense of physical corneal change…. just visual improvement when the
lenses are removed.

What is the difference between Corneal Refractive Therapy and Paragon CRT?

Corneal Refractive Therapy is the process of using a therapeutic contact lens to reduce myopia by reshaping the
corneal surface while you sleep.  Paragon CRT is the product for this therapy.

If I discontinue CRT, will my vision to return to normal?

There are no recorded permanent corneal changes post-treatment.  Generally, the more myopia being reduced,
the longer it will take for the corneal curvature to return to normal.  For instance, if your pretreated correction was -
4.50D, it would take a few days longer to return to normal than if the pretreated correction was -1.50D.  

My driver’s license is marked that I need corrective lenses to operate a motor vehicle.  What do I do about that?
Your eye care professional will supply you with a document that states you are participating in a visual therapy
program that eliminates the need for corrective lenses during working hours.  The document should have an
expiration date and you should have your driver’s license updated with a new vision screening through your local
DMV office to reflect this change, before the expiration date.

What happens if I lose or damage a lens?

Corneal Refractive Therapy is different than wearing regular contact lenses.  If you discontinue wear for one night,
your vision may be impaired the next day.  Previously worn glasses or contact lenses may not help.  Immediate
replacement is necessary!  Having a spare pair of lenses is strongly recommended.

I used to wear contact lenses, but stopped due to discomfort.  Am I a candidate for Corneal Refractive

Paragon CRT lenses are worn at night while you are sleeping.  This greatly reduces any discomfort normally
experienced while wearing contact lenses during the day.  

I have astigmatism.  Am I a candidate for Corneal Refractive Therapy?

Paragon CRT is designed to correct myopia with to 1.75 diopters of astigmatism.  Each individual should be
evaluated by a certified eye care professional to determine if CRT is right for your visual requirements.

I wear glasses.  Am I a candidate for Corneal Refractive Therapy?

The transition from wearing only glasses to Paragon CRT should not be a concern.  About 18% of the patients in
the FDA study were non-contact lens wearers.   The dropout rate related to discomfort was only 3.9%.
Myopia control with Paragon CRT®