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Corneal Refractive Therapy and Myopia Control (CRT)

Holly discusses Corneal Refractive Therapy

Corneal molding, or CRT, is a method used to correct or slow the progression of myopia (nearsightedness) by wearing special hard contact lenses that reshape your eyes overnight, allowing you to be free of glasses or contact lenses during day. While success rates for CRT are generally higher for more mild vision prescriptions, stronger prescriptions can also be corrected. According to FDA trials conducted on CRT lenses, more than 65% of CRT patients were provided with 20/20 visual acuity. A whopping number of more than 90% of CRT patients achieved 20/40 vision or better (this is the legal requirement for driving without vision correction in most states).

The process is quite simple. The CRT molds are inserted at bedtime and worn as you sleep. Throughout the night, the lenses gently reshape your cornea so that your vision is clear the following morning. The correction is temporary, so in order to maintain sharp visual acuity on a daily basis, you need to wear the CRT reshaping lenses every night.

CRT is very suitable for nearsighted people who are not appropriate candidates for vision correction surgery, such as children. Individuals of all ages with healthy eyes can try CRT. People who require vision correction and engage regularly in sports or work in extremely dusty, dirty environments will also appreciate the convenience of CRT.

CRT Q&A:

What is corneal refractive therapy?

It is a way for us to change a patient’s prescription without actually performing surgery to the eye. The patient wears a hard, breathable contact lens at night that reshapes the surface of the eye while he or she sleeps. This manipulates the prescription and allows the patient to see clearly during the day without the help of contact lenses or glasses.

Who is a candidate for CRT?

Any nearsighted patient with healthy eyes is a possible candidate for CRT.

Can children wear them?

While CRT works for adults, it was specifically designed to slow the progression of nearsightedness in children. If we begin CRT on a child at the first signs of nearsightedness, we can slow down or possibly even stop the negative changes to their vision over time.

Is it painful?

When you first begin wearing CRT molds, you will have lens awareness until you get used to having hard contact lenses in your eyes. This slight discomfort will quickly subside and you will have no trouble wearing these molds while you sleep.

Are they difficult to put in and remove?

Inserting CRT molds is slightly different from regular contact lenses because they are designed to suction to the center of the eye. Once you learn the technique, it is very simple. You must use a special plunger to remove the molds from your eyes in the morning, which is also a very easy process.

How long does it take to correct my vision?

This depends on your specific prescription. The higher the prescription, the longer it will take to fully correct your vision. Low prescriptions can see full correction within the first night of wearing the molds. For higher prescriptions, it can take longer to stabilize the changes to the surface of the eye and optimize the vision.

Is it permanent?

No. You must continue to wear the molds to ensure optimal vision. If the molds aren’t continuously worn, your cornea will gradually return to its original shape.

What happens to my vision if I stop wearing them?

You will go through a similar transition period to when you began wearing molds as your vision gradually changes back to your original prescription. It can take a week or so for your vision to return to a point where you can comfortably wear your glasses or regular contact lenses again.

Can I see when I’m wearing the molds?

They do function just like regular contact lenses. While they are meant to be worn while you sleep, you can easily put them in before bedtime and then continue to see well as you complete your nightly routine.

How much do they cost compared to regular contact lenses?

CRT molds are very similar in price to daily contact lenses. They are slightly higher than a monthly or biweekly contact lens, but they are extremely affordable.

Will my insurance cover them?

Your insurance treats them just like regular contact lenses. So if you have vision benefits that contribute toward contact lenses, these benefits will also apply to CRT molds.

How often do I have to purchase new ones?

This will vary from patient to patient. It is dependent on how they are cared for and how the molds hold up over time. Typically they are replaced once a year, but there are times that they can be worn for over a year.