Myopia, or nearsightedness, is an eye disorder that causes light to focus IN FRONT of the retina instead of ON the retina, causing distance objects to appear blurry. If you experience one or more of the following symptoms, you should be evaluated for myopia:
Squinting
Needing to sit closer to see
Holding books very close to read
Excessive blinking
Rubbing eyes frequently
Poor grades or falling behind in school
Historically, myopia has been treated with the use of glasses or contact lenses. LASIK is another method to surgically correct myopia. One lesser known treatment option is ortho-keratology (ortho-k), also known as corneal refractive therapy (CRT). When worn overnight, corneal reshaping contact lenses will gently correct the curvature of the cornea, resulting in a corneal shape that focuses light correctly onto the retina. After removing the lenses in the morning, distant objects should be in focus and you will be able to see clearly throughout the day without having to wear glasses or contact lenses.
CRT can provide more natural vision because you won’t have to wear glasses or contact lenses during daytime hours. This helps eliminate distortions, reflections or blur from dirty lenses, as well as inherent discomfort or dryness from contact lens wear.
Most patients have rapid improvement in the first few days of treatment and achieve optimal vision in approximately 10-14 days. In one study of 159 eyes, 67% of patients obtained 20/20 vision in at least one eye, and 94% achieved at least 20/40. There is a small percentage of patients that will not improve enough to function under all conditions without additional correction. There are many studies currently being performed researching the possibility that ortho-k can slow down the progression of myopia. Early results are promising. This would lessen the prevalence of complications associated with myopia such as retinal detachments, early formation of cataract, and glaucoma.
CRT is temporary. If you stop wearing your lenses your vision will return to its original state usually within 72 hours. The more change to your cornea with treatment, the longer it will take for the corneal curvature to return to normal. Also, if you discontinue wear for one night, your vision may be impaired the next day. Glasses or contact lenses you wore prior to CRT will not be effective. It is for this reason that having a spare pair of lenses is highly recommended.
Use of CRT lenses is safe. There are small risks present with the use of any contact lens. These risks are minimized with proper lens care. The therapy is not painful. Initially, you may have a slight awareness of the lens, but you will not feel the lenses when you sleep. You will not be able to feel that the lenses are working, you will simply see the visual improvement when the lenses are removed in the morning!
Only certain people are good candidates for CRT. Those with high myopia, large amounts of astigmatism, or large pupil size are not ideal candidates. Children between 8-12 years old, adolescents and adults under 40 are the best qualified. The FDA has placed no age restrictions on CRT wear. It can be a great option for children and teens that are active in sports or other extracurricular activities. It can also provide children a great boost in self-confidence. Patients who are older and require reading glasses or bifocals may still be a candidate. Distance vision can be corrected with CRT and wear reading glasses for close work. Or monovision may be an option: one eye corrected for distance and one eye corrected for near. Just as all patients can’t be fit with CRT lenses, not all eye doctors can perform this procedure. It requires additional certifications and training, and a considerable amount of time to ensure success and to properly care for the patient.