Overnight Contacts: CRT, OrthoK
Sleep your way to clear daytime vision.
Corneal Refractive Therapy (CRT) or Ortho-keratology (Ortho-K) is an FDA-approved overnight therapy that frees you from contacts and glasses during the daytime. Specially-designed contacts are worn while you sleep. The next morning, the lenses are removed, and the world is in focus without glasses or contacts. Unlike Lasik, this treatment is reversible. Once lens wear is discontinued, the cornea returns to its natural shape.
Here in the Bay Area, where there is a high level of myopia and astigmatism, CRT is a popular option for adults and children. For children, these therapeutic lenses may help slow down the myopia progression. It is also an alternative to LASIK for those that are seeking the freedom and liberation of LASIK without the permanent effects of surgery.
Who is a good candidate?
Are you one of these people?
Consistently exposed to dusty, dirty environments
Active in water sports, winter sports, and full-contact sports
Interested in LASIK but unwilling to commit to permanent surgical change
Experiencing difficulty with daytime wear contacts and glasses
Is it safe??
There are horror stories floating around about all contact lens wear because no contact lens use is risk-free. However, longitudinal studies have proven that CRT is a safe and effective therapy when used correctly, and therefore CRT received unanimous FDA-approval without age restriction in 2002.
At our office, many patients begin CRT as young children or have CRT as their first exposure to the world of contacts. We closely monitor our patients throughout the year and are proud of our safe track record. Your CRT exam fee will include designing custom lenses, classes on care, classes on insertion/removal, and frequent, regular follow-ups with our doctors.
Will insurance cover CRT / Ortho-K?
In general, CRT / Ortho-K is considered an elective, cosmetic treatment, and your insurance will not cover the cost of your CRT exams. Certain vision plans may allot a monetary amount towards the purchase of contacts.
I want to learn more. What next?
Schedule your CRT consult and find out if CRT is an option for you. If you are a new patient, please bring a copy of your complete eye records, your glasses, and contacts prescription.
Ortho-Keratology Chinese Summary
角膜塑形术 （Orthokeratology) 是用一种特殊的隐形眼镜来减低或消除近视和散光的医疗方法。患者只需晚上睡觉时戴上Ortho-K 隐形镜，就可达到矫正视力的目的。它的原理是用这种特殊的隐形眼镜来改变角膜的形状从而改善视力的效果。
轻度 （ 小于200度）和中度 （小于 500 度）近视 效果最好，可能矫正到20/20 至20/30. 深度近视（大于 500度）也可大大改善视力，以至不戴眼镜就可行走。
首先根据患者的眼球形状，选择合适的Ortho-K 隐形镜。隐形镜会使患者的眼角膜形状渐渐减少曲率，更接近球形。这就会减低近视和散光。在这过程中，眼角膜慢慢的变形，患者的视力逐渐得到改善。 Ortho-K 隐形镜的材料是特殊设计制成，它能加速角膜的变形。 经过2到6周，矫形可达到最好程度，然后要用保型用隐形镜来保持和稳定角膜形状和改善了的视力。
Ortho-K 隐形镜以经被FDA 批准使用。多家大学完成了矫正术的研究，并一致认为角膜角矫正是安全的，无副作用的。