Improve Your Vision While You Sleep!
Corneal Re-Shaping Eye Retainers
The most exciting thing happening in eye care today is the use of corneal re-shaping eye retainers:
- to mold away myopia (nearsight), hyperopia (farsight), and astigmatism in adults and children
- to prevent myopia from developing and worsening in children.
Ortho-K (short for "Orthokeratology") goes by a number of different names, among them Corneal Molding, Corneal Refractive Therapy (CRT), Corneal Re-Shaping, and "eye retainers". Developed over the past 50 years, Ortho-K has gained wide recognition as a safer and less expensive alternative to LASIK refractive surgery. Using specially designed extended wear rigid gas permeable contact lenses, we can re-shape the cornea while you sleep, so when you wake up and remove the lenses, your vision is clear all day without glasses or contacts. Besides stopping the progression of myopia in children, Ortho-K lenses can also be designed for people of all ages to temporarily eliminate myopia, hyperopia, astigmatism, and presbyopia.
Myopia has become an epidemic in the United States and around the world, and there is a revolution occurring in our understanding of how it progresses and how to stop it.
To understand how the eye becomes myopic, we need some basic knowledge about the eye:
- Emmetropia (clear far sight, without any effort from the focusing muscles) is when the eyeball's CENTRAL focus point of a distant object is on the retina.
- Hyperopia (known as "far sight"; requiring effort from the focusing muscles) is when the eye's CENTRAL focus point of a distant object is behind the retina. It is usually due to an eyeball that has become too short, requiring the activation of the focusing muscles to change the shape of the internal lens to bring the focus point forward onto the central retina. Small amounts of hyperopia can be brought into clear focus in this manner, but with larger amounts or in attempting to view near objects, the focusing muscles must exert even more effort to bring the focus point forward, and with increasing age they cannot change the lens power enough to bring the focus point all the way forward to the retina to obtain clear vision.
- Myopia (known as "near sight", without any effort from the focusing muscles) is when the eye's CENTRAL focus point of a distant object is in front of the retina. It is usually due to an eyeball that is too long, so distant objects are focused in front of the retina, causing blurry distant vision. It is called "nearsight" because when an object is brought near to the eye, the focus point moves back onto the central retina, resulting in clear near sight.
- The central retina is where the highest density of photoreceptors is located, and that is where we have the clearest vision. Therefore, when we look at an object, our brains point the central retinas directly toward whatever it is we are viewing in order to obtain the clearest vision. It is our central vision that we notice when we say something is clear or blurry. We do not generally pay attention to the clarity of vision in our periphery because there are fewer photoreceptors out there, causing the peripheral vision to be less clear than our central vision. Nevertheless, it has been proven that the peripheral retina is what causes the eye to become emmetropic, myopic, or hyperopic!
- The eye becomes emmetropic (called "emmetropization") in the process of development and maturation. All components of the eye that contribute to the ultimate refractive status (corneal curvature, internal lens power, eyeball length) must be coordinated to obtain central focus on the retina and thus clear vision. If the internal lens doesn't become strong enough, for example, then the cornea must become flatter or the eyeball must grow longer to maintain clear vision. If the cornea becomes more curved, then the lens must become stronger or the eyeball must stop growing longer. The process works differently for everyone because not everyone ends up with clear effortless distant vision.
- Eyeballs with peripheral hyperopia (whether they are emmetropic, myopic, or hyperopic centrally) become elongated and develop myopia (See Figure 1). Studies show that eyeballs exposed to peripheral hyperopic defocus, even for as short a period of time as 30 minutes become elongated and develop myopia. We now know that conventional myopic correction of children using single vision "minus power" eyeglasses or contact lenses creates peripheral hyperopic defocus, which causes these children to become more myopic. Most eye doctors are unaware of these studies and continue to recommend single vision correction for their young patients (See Figure 2)
- Eyeballs with peripheral myopia generally do not become myopic. In fact, we now know that we can create peripheral myopic defocus with optical devices that are instrumental in stopping the eyeball from growing longer and more myopic! There are a number of ways to create peripheral myopic defocus, including progressive bifocal eyeglass lenses, progressive bifocal contact lenses, and Ortho-K (Orthokeratology). The method with the highest success at stopping myopia progression in children is Ortho-K. (See Figures 3-5)
- Astigmatism is when the eye develops not one power, but 2 different powers 90 degrees apart, usually the result of the cornea becoming "warped" with two different power curvatures. This results in not one focus point, but two split focus points at different distances from the central retina in line with the eyeball's visual axis. These split focus points may be combinations of myopia, hyperopia, or emmetropia.
- Presbyopia is when the internal crystalline lens becomes less elastic with age, resulting in the inability to bring the near focus point forward onto the retina.
Below: Figure 1 showing how an emmetropic eye with peripheral hyperopia stretches and becomes elongated and myopic:
Below: Figure 2 showing how a single vision contact lens causes peripheral hyperopia, which in turn causes eyeball elongation and central myopia:
Below: Sketches demonstrating how Myopia Control works:
Below: Sketches demonstrating how Ortho-K (Corneal Molding) for myopia works:
Below: Sketches demonstrating how Ortho-K (Corneal Molding) for hyperopia works:
There are a number of different Ortho-K lenses available, but Dr. Jeruss prefers to use the WAVE computer designed lenses, which are the only ones that can be custom designed with:
- any overall lens diameter (to fit different sized corneas)
- any treatment zone curvature and diameter (to correct much higher refractive errors than other lenses are capable of, and to adjust for different pupil sizes)
- any reverse zone curvature and diameter (to create faster treatment)
- any slope between the treatment zone and the reverse zone (to create different amounts of peripheral myopic defocus for stopping myopia progression)
- any alignment zone width and curvature and slope (to improve lens centration)
- any edge width and degree of lift (to improve comfort)
- any overall power (to allow for clear vision with daily wear, if desired)
- any center and edge thickness (to prevent lens warping and improve comfort)
Below are screen shots of pre- and post- treatment topography maps and WAVE lens design window:
Above: Figure 12: pre-treatment corneal topography map.
Above: Figure 15: post-treatment corneal topography showing the flattened central treatment zone and surrounding steep ring created by the lens "pocket" allowing the central cornea to expand peripherally. This steep zone acts to create peripheral myopic defocus which stops the progression of myopia.
Above: Figure 16: WAVE lens design screen
"What can I expect?"
Typically, the lenses are worn during sleep, and removed upon waking, but because they do have your prescription power built in, you'll be able to see clearly with them on as well. After the initial measurement and fitting, we will schedule a dispensing visit to teach you how to use and care for your lenses, and then several follow-up visits: usually 1 week, 4 weeks, and 3-6 months after dispensing the lenses.
The vision improvement with corneal molding is temporary, and may tend, in the first few days, to lessen toward evening. This can be alleviated by re-inserting the lenses for a brief time during the day. All day clear vision is usually achieved within 3-7 days. The number of sleep hours may affect the results at first, but over time it will not make much of a difference.
"What are the benefits?"
Besides the obvious freedom from the hassle of glasses or contact lenses during the day, wearing corneal retainers has one other amazing benefit. Research has proven that they slow down and even halt the progression of nearsightedness in children by slowing down and stopping the elongation of the eyeball!! Myopia has become an epidemic, and besides the risk of becoming more and more dependent on thicker and thicker eyeglass lenses, people who are highly myopic tend to have an increased chance of developing glaucoma and retinal detachments. We can prevent this!
"What are the risks?"
As with all contact lenses there is a risk of corneal abrasions, inflammation, infections, and reactions to some of the chemicals in the solutions used for cleaning and storage. Studies have shown that overnight corneal molding carries no increased risk of bacterial corneal infection compared to other types of contact lenses.
"Why haven't I heard of this before?"
Unfortunately, most eyecare has turned into "fast-food" national commercial optical retail stores, whose main concern is how many "customers" can be crammed in and how many pairs of eyeglasses can be sold. The doctors who work there do not have the knowledge or specialized training to perform Corneal Molding, and for them it is "too time consuming". Ophthalmologists are surgeons who have little or no knowledge of Corneal Molding other than it's increasingly taking away from their LASIK business! Instead of trying to prevent their patients' eyes from worsening, they actually contribute to the epidemic of myopia by prescribing single vision eyeglasses and contact lenses for their young patients. If any of them ever tells you that your child "doesn't need bifocals", it is because they are unaware of the latest research on myopia prevention.
Dr. Jeruss has been successfully performing Ortho-K for over 30 years, longer than anyone in the Atlanta area. Call us at 770-578-1900 and see if you are a candidate!
For more information, please see the following web sites: