If you’ve ever heard the phrase, “Don’t make that face, it will freeze that way,” you’ll be surprised that it contains a nugget of truth. Outside of sudden paralysis from brutalism toxin or an aneurysm throwing a clot, your eyes are the only part of your face that wear out from overuse.
Your eye naturally contorts throughout the day for a lot of reasons. Unfortunately, repeated strain translates to permanent damage to the shape. The process of corneal molding (orthokeratology) restores the shape to repair the strain.
Once a set of lenses has been created, they can be used for years without the need to be adjusted or changed.
Proper vision depends on your cornea, lens, and pupils adjusting to let in varying amounts of light. Focusing on distant and near objects requires different focal lengths. To achieve these lengths, your eye adjusts the lens and cornea shape to compensate.
Read on to learn more about how orthokeratology helps people live better.
Corneal Molding Facts
On the positive side, it takes years of repeated strain to warp your cornea and create myopia. On the negative, it takes a lot of time to reshape it as well.
Non-congenital myopia is a problem for a developing world. Studies indicate myopia occurs 2.6 times more in urban youths than rural youths. The presence of more objects that require more attention wears us out.
Check here for a more detailed overview of the process of orthokeratology itself. To summarize, an optometrist creates a set of customized contact lenses based on your cornea topography. You wear nighttime contacts and go without contacts or glasses throughout the day.
With that in mind, here are seven things to consider about orthokeratology and corneal molding.
1. Cornea and Lens Differences
The eye uses a variety of mechanisms to shape and interpret light. Adjustments in one area tend to create reflexive changes in other areas.
The cornea protects the eye from damage, like a windshield. The iris contracts, allowing light in. The lens then focuses that light onto the retina.
When the cornea’s shape changes, the light doesn’t go through the pupil area at the same angle, which makes the lens refract incorrectly.
So, when a corrective ortho lens is applied, it is on the cornea and not your eye lens. This distinction confuses a lot of people.
Both the lens and the cornea are malleable. They can and do change shape as part of their normal work. The cornea’s shape is largely affected by the aqueous humour, fluid between the cornea and iris.
The lens is shaped by ligaments attached to the ciliary body. These two structures suffer different problems from strain, which is why eye pain can feel like anything from an ache, to a string, to pressure.
2. The Molding Effect Comes from Pressure
Wearing the contact lenses overnight doesn’t physically reshape your cornea. That would damage the cornea too much. Instead, the contact lenses apply pressure to the aqueous humour beneath your cornea.
Since the contact lenses are semi-permeable, they allow in a different amount of airflow than you would normally have. That airflow change creates a layer of fluid on the outer surface of the eye. This fluid is essentially made of a build-up of the same lubricant you get from blinking.
The topography used to create the lenses increase this fluid in some places and decrease it in others. The combined effect redistributes pressure in the aqueous humour and that affects the shape of the cornea.
3. Lasting Effects
The ultimate goal of orthokeratology is to retrain the cornea to maintain the best shape for functionality. In the early stages of treatment, the effect of an overnight wearing lasts a few days.
Early effects last about two days while continued wearing will stretch that to four days or more.
The lenses themselves provide a proper vision prescription like any other lenses or glasses. You could wear them during the day, but they tend to be uncomfortable and stiffer than normal ‘soft-wear’ contacts.
During the daytime hours, when the lenses aren’t worn, the cornea shape provides the same vision as a corrective lens. The cornea maintaining the corrected shape also limits eye strain, protecting other parts of the eye.
Eventually, the fluid pressure reverts to its resting state. However, the molding efforts also slows down further degeneration.
4. Myopia is on the Rise
The last 30 years have been bad for humanity in regards to myopia statistics. As already pointed out, it’s more common in urban environments. Worse, it’s also more common in the developed world.
Biologically, our eyes were designed to operate under conditions somewhat different than the ones we currently live under. The presence of electrical lighting pushes us to stay focused beyond a point we would have even two hundred years ago.
Instead of resting our eyes for the 10-12 hours of darkness that exist in nature, we rarely go more than six hours without some form of electrical light. We also look at words and shapes much smaller than we would normally encounter.
The earlier we start to overuse our eyes, the faster myopia develops. This snowballs future strain as the eye has to work harder to maintain adequate vision levels.
Myopia leads the eyesight degeneration charge but hyperopia and astigmatism are right behind. These conditions also benefit from orthokeratology and come from cornea shape among other causes.
5. Insurance Doesn’t Cover Orthokeratology
The lack of insurance coverage for treatments forms one the more troubling facts about orthokeratology. This, despite that the WHO suggests myopia and vision impairment correction should be available to all.
In the United States, orthokeratology falls under elective procedure notation. The efficacy of the treatment is not at issue, it is that the treatment has a cosmetic component.
Seeing properly without assistance through the day isn’t vanity, it’s practicality. Glasses leave peripheral vision spaces that create sources of strain.
Contact lenses mess with the natural chemistry of the eye. That’s why saline rinses are necessary and you sometimes get sticky or dry eyes from prolonged contact usage.
6. Orthokeratology Has a Long History
Even though myopia has been on the rise for 30 years, orthokeratology has been around, but underused, for longer.
The original discovery was in the 1940s. It was found that glass contact lenses had an overall effect on the eye. Initial tests of contacts were concerned with any damage that the new technology might cause.
As ophthalmologists reviewed the data, they noticed that the shape of the cornea could be molded by microns from contact lenses. Microns may not seem like a large thing by most scales.
Applied to the eye’s magnification abilities, microns scale quickly.
Through the 60s and 80s improvements in the shaping of contact lenses made more minute adjustments possible. With the 90s computer modeling and corneal topography became possible.
This final step allowed the already advanced ability to shape lenses precisely to be made more effective. Ophthalmologists could now know what shape was needed in addition to the ability to make that shape.
Topography didn’t make orthokeratology possible, it only made the effects possible to last longer.
7. Children Benefit
Children make better candidates for orthokeratology for a couple of reasons. First, their younger age prohibits them from receiving certain procedures. Long-term effect and minor surgeries such as refractive surgery and LASIK create too much risk for children.
Secondly, because they are young, their eyes are more prone to changing shape. There are far more adults that need glasses and corrective lenses than children. This is because strain is cumulative and also because young eyes adapt better.
Starting an orthokeratology treatment early limits misshaping damage. It also trains the eye to maintain a proper shape for longer.
Third, children fight the stigma of glasses and corrective lenses fiercely. Glasses are still seen as a negative by many children. Overnight orthokeratology lenses provide benefits to social status.
It’s also easier to participate in sports without protective glasses or possible contact lens loss.
Finally, orthokeratology fittings don’t happen all at once. It takes several visits and mappings (three, on average) to get the right lenses to provide maximum benefit. It’s easier to get a child in for multiple fittings than an adult.
Adults need to maintain function and disruption to their schedules comes at a price. This leads to many adults taking more time to get a proper fitting, which means more time to see results.
Right in Sight
The benefits of corneal molding echo into the future. Reduced headaches, a better quality of life, and restored vision are only the beginning. Making healthy life choices is difficult, but seeing returns on self-care is always amazing.
Eating right is a great way to maintain eye health as well. Read more and stay tuned for more lifestyle and health tips.