Frequently Asked Question
- A Brief History of OrthoKeratology
- Corneal Reshaping through Orthokeratology (OrthoK)
- Pharmacological Control of Myopia With Atropine
- Gas Permeable (rigid or hard) Contact Lens Wear
- Accommodative Vision Therapy
- Vision Undercorrection; Keeping Eyeglass Prescriptions Below 20/20 Vision
- Myovision Lenses from Zeiss
- Bifocal and Multifocal Eyeglass Wear
- Inducing Peripheral Defocus; Altering Peripheral Refraction
- Caring for Orthokeratology Devices
- The “Don’ts” of Wearing Orthokeratology Lenses
- Common Temporary and Reversible Challenges Using Orthokeratology
OrthoKeratology (also known as OrthoK and Corneal Refractive Therapy – CRT) has a 50 year history of correcting myopia in children. In the early days of contact lenses, doctors noticed that their patients wearing hard contact lenses would report less blurry eyesight and seeing better at distance after removing the contacts than they did before they put them in. They also noticed that the vision for some patients in these hard lenses changed less than people in wearing just glasses. They discovered the reason for this was that the lenses that had these effects fit flatter on the curvature of the eye than standard contact lenses, exerting a gentle pushing effect which temporarily reduced the amount of nearsightedness for the wearers. The practice of prescribing these “flatter” lenses went on for many years, until a company filed a special design and healthier contact lens plastic for approval by the FDA. The FDA approved accelerated OrthoK in the late 1990s for children of all ages. The procedure involves the child putting Orthokeratology lenses in their eyes before bed – when the eyes are closed they don’t feel the lenses; while they sleep they undergo gentle corneal reshaping which results in corneal refractive therapy. Upon awakening when they remove the lenses, they see perfectly clear all day until bedtime, when they need to reinsert the lenses. There is no age restriction for the use of Orthokeratology.
The Doctors at The Myopia Institute have many years of combined experience treating children and adolescents with Orthokeratology, Paragon CRT, Vision Shaping Treatment and other OrthoK technologies.
Corneal reshaping therapy options such as OrthoK, cornea refractive therapy including Paragon CRT (vision shaping treatment) are particularly helpful when seeking to improve eyesight in children with nearsightedness and astigmatism, and reduce change in vision, specifically myopia in children and may in some cases reduce the risk of children with myopia advancing to high myopia. If you are interested in managing your vision or the vision of a loved one with nearsightedness and concerned about vision changes, please contact an Eye Myopia doctor near you or read through our website to learn about other options that may help improving your child’s eyesight.
The curve of the cornea (front surface of the eye) is largely responsible for refractive errors such as nearsightedness (myopia), farsightedness (hyperopia) and astigmatism, the culprits behind blurry eyesight. For nearsightedness (myopia), the cornea may be steeper than average, causing light to enter the eye producing a blurry image for the retina. For farsightedness (hyperopia), the cornea may be flatter than average, which, depending on the age of the individual, creates problems focusing at different ranges of vision (near vs far). Astigmatism is when the cornea is steeper in one meridian yet flatter in another, causing images that enter the eye to be distorted to some degree. Corneal reshaping, either surgically (LASIK, PRK or Orthokeratology) can minimize or eliminate the refractive error caused by a cornea that is too flat, too steep or astigmatic. These methods seek to flatten the curve of the cornea in nearsighted (myopic) individuals surgically or non-surgically with Orthokeratology lenses (OrthoK lenses) in a process commonly known as corneal reshaping, cornea refractive therapy (Paragon CRT), corneal reshaping therapy and vision shaping treatment (VST)
Contact lenses were mainstreamed in the early 1960s with the introduction of Polymethylmethacrylate (PMMA) lenses to the market. These lenses are known historically as “hard” lenses. At the time PMMA lenses were introduced to the market, the only corrective option for millions of people was eyeglasses. A few years after the introduction of PMMA contact lenses, patients were reporting some interesting experiences; some noted that they could see for a period after they removed their contacts without the aid of glasses. They might wear their contacts all day and remove them to go to a cocktail party or such. Doctors noted that in some cases progressive myopia slowed down in people who had repeatedly year after year manifested increases in prescription. Doctors discovered that lenses that were fit flatter than the curvature of the cornea were the reason for both phenomena, so they started purposefully fitting the contact lenses flatter. The results were dramatic in some cases. People with generally less than a certain amount of prescription could remove lenses and see, sometimes for an entire day. The resulting therapy took on the name Orthokeratology, or OthoK for short. “Ortho” is latin for straight and “keratology” is the science of altering the shape of the cornea. While interesting and helpful for many patients, PMMA material is not permeable to oxygen, so there were some inherent risks in extending wear of these lenses to achieve the desired effect. Also, fitting them to achieve the desired effect was an arduous and inexact science.
In the 1970s plastics for contact lenses were developed that had a higher permeability to oxygen. The flourosilicon elastomers proved safer and healthier for the eye and reduced the risks of Orthokeratology, but fitting these lenses was still challenging for doctors and time consuming for patients.
In the 1990s plastics were developed that reached a new level of oxygen permeability. These “hyper-permeable” lenses made sleeping in gas permeable contacts much safer. In the late 1990s, a company also developed a lens shape, known as “reverse geometry” that greatly increased the ease of fitting and success for Orthokeratology patients. Combining the healthier materials with the reverse geometry dimensions, Orthokeratology became much more popular and was mainstreamed. It provides excellent vision without glasses or contacts for thousands of people worldwide. Studies have been performed that demonstrate the safety and efficacy of the procedure, and other studies have been performed that demonstrate that Orthokeratology is successful at managing myopic shift, providing the only known way of providing myopia control for contact lens wearers. Orthokeratology is not without risks, but the risks of Orthokeratology are very similar to the risks one has wearing any contact lens, specifically extended wear contact lenses (lenses people sleep in). This includes an infection of the cornea known as a keratitis, which is treatable if diagnosed promptly.
Options such as Orthokeratology (OrthoK) cornea refractive therapy including Paragon CRT vision shaping treatment) are particularly helpful when seeking to improve eyesight in children, and reduce change in vision , specifically myopia in children and may in some cases reduce the risk of children with myopia advancing to high myopia. If you are interested in managing your vision or the vision of a loved one with nearsightedness and concerned about vision changes, please contact one of our eye doctors near you or read through our website to learn about other options for improving your eyesight.
Several studies have shown that atropine eye drops can reduce myopia progression by temporarily paralyzing the focusing muscle inside the eye. (Atropine also causes the pupil to dilate widely.) One such study is the Atropine in the Treatment of Myopia (ATOM) study, which tested 400 children aged 6 to 12 over a two-year period. Atropine is one of a class of drugs from the family solinaceae. In general, atropine lowers the activity of all muscles regulated by the parasympathetic nervous system. The muscles in the eye that control focusing (accommodation) are some of these muscles. Topical atropine is used as a cycloplegic, to temporarily paralyze accommodation. It does this by paralyzing the ciliary muscles, whose action inhibits accommodation to allow accurate refraction in children.
Gas permeable contact lenses generally refer to contact lenses manufactured from a class of polymers which incorporate silicon in the matrix, whether hard or soft lenses. The presence of silicon enables oxygen to pass through the plastic to the eye, oxygen being advantageous to the health of the cornea, the surface of the eye. Historically, gas permeable referred to rigid plastic lenses that took some getting used to in terms of comfort. In the late 1990s classes of silicon-based soft lenses were developed, so the term “gas permeable contact lenses” is not limited to the rigid kind anymore. For the purposes of our discussion, “gas permeable” will refer to the more rigid type of contact lens. In the 1960s, the first rigid contact lenses were brought to market. These lenses were made of a plastic impermeable to oxygen, polymethylmethacrylate (PMMA). The introduction of these lenses marked the first time that the public was mass marketed a vision correction product other than eyeglasses. After a few years of fitting these lenses on patients, optometrists noted interesting differences in wearers of PMMA lenses compared to eyeglass wearers. Certain patients fit in the PMMA lenses demonstrated slower rate of myopia progression, in some cases a total halt, while some patients reported that, for a certain amount of time after they removed the lenses, they could see better. In some cases those people reported not having to wear glasses or contact lenses for many hours after removing the lenses. Doctors attributed these effects to wearing of PMMA lenses that were fit flatter than the curvature of the cornea. It appeared that lenses fit flatter than the curve of the cornea exert a gentle pressure on the cornea, causing the cornea to temporarily take on a slightly flatter shape and remain molded that way for a certain period of time after the lens was removed. While that would explain seeing better after removing the lenses, (flatter corneas experience less blur from myopia) the phenomenon of stabilization remained a mystery until only recently, when scientists and doctors began to suspect that peripheral refraction played a role in controlling the worsening vision people with myopia undergo. In the 1970s, gas permeable plastics were introduced and gradually replaced the PMMA lenses as gas permeable lenses were healthier for the eye.
Several studies have shown a positive and several studies have shown no correlation between wear of standard gas permeable contact lens and myopia control effect, although the results of studies to determine the correlation between the two has not been conclusive. This is likely due to studies not standardizing variables such as quantifying the amount of flattening the lenses provided to each individual cornea, corneal thickness and malleability constants, contact lens diameter and other individual characteristics that might have affected the study outcomes. These studies are referenced for your convenience in the research library section of this website.
The eye receives light and processes it. This process is similar for viewing near and distant objects. Looking at distance objects differs from looking at near objects in how the musculature of the eye adjusts the focus mechanism, the Lens. Adjustment of focus for viewing near objects is termed Accommodation. When viewing distance objects (objects greater than 20 feet or 6 meters from our eyes), the eyes are aligned straight ahead and the line of sight of each eye is approximately parallel to one another. Light from the distance target enters the eye and is focused on the Retina, or light-sensitive tissue on the back of the eye. When looking from a distance target to a near target, the eyes must change focus. The eyes must also turn in towards each other to bring proper focus onto the near object (Convergence). This change in focus only occurs when looking from distance to near. When looking up from near work, or near to distance, the eye un-focuses (releases accommodation) and the eyes straighten and the lines of sight go from being converged on a near target to being parallel again. The process of going from a position of convergence (looking at near) and accommodation (focusing at near) to being straight and unaccommodated for distance viewing is called divergence. The processes of convergence and divergence are controlled by the musculature surrounding the eye. These muscle actions for convergence and divergence are intertwined with the muscle that controls the focus for the lens of the eye so when the eye converges, the eye muscle focuses the lens for near and when the eye diverges, the eye muscle unfocuses the lens for distance. The eye muscles receive information for when to converge or diverge, direct the eyes to the left, the right, up or down based on information shared between the retina (image positioning information) and the nuclei (eye movement information). If an object passes to the left of you, the image of the object will fall on an area of the retina that corresponds to your left side. The nuclei will receive this signal and relay another signal to the eye muscles to look left in order to move the image of the object towards the area of the retina where the image is best viewed (the Fovea). Muscles inside the eye then control the process of accommodation and unaccommodation. When the act of focusing occurs, the mind assumes that a near object is to be viewed and convergence action kicks in. How does the mind know you are viewing a near target? When an object directly in front of you is brought closer to you, the image size of the object projected on the retina increases and the retinal image blurs. This slight amount of blur is the stimulus for the focus mechanism to kick in. Proximity of the object and blur are stimuli that activate the convergence/accommodation nuclei in the brain. The visual system transfers information about object proximity and blur to nuclei responsible for accommodation. Impulses are sent through the accommodation/convergence pathway. The impulses cause muscles inside the eye to increase the convexity of the lens of the eye. The increase in convexity increases focusing power, enabling focus at near. These stimuli cause accommodation for near and the eyes converge. When the object moves away from you, the image magnification on the retina decreases, the stimulus to converge and focus for near decreases as the eyes diverge to see the object at distance. The muscles in the eye cause the convexity of the lens to decrease, decreasing focusing power. This moves the point of focus out to distance. There is no convergence without accommodation and no accommodation without convergence. There is no divergence without unaccommodation and vice-versa. Accommodative vision therapy attempts to address one or more of the various errors of the accommodative convergence system and there are no long term, blind, double-masked randomized clinical studies to show it is effective for controlling or reducing myopia.
Undercorrecting involves determining the appropriate prescription for a person to see at distance 20/20 or better and “backing off” the prescription so that distance vision is slightly blurrier than 20/20. Historically but with no scientific studies to back it up, people and doctors alike have recommended undercorrection as a means of managing myopic progression. While it is possible to adapt to a lower prescription it is not what is best for anyone who hopes to retard the progression of myopia. Scientific studies elsewhere in this website have shown that blur is actually a stimulus to more nearsightedness; the eye changes it’s refractive state in response to blurry images received by the retina, or back, of the eye. The only proof that undercorrection works comes from a study of just 33 Japanese children in 1965, and from studies on chicks in the 1990s and these studies have since been attacked as lacking rigour or relevance.
Every 2nd child in urban populations in Asia suffers from myopia: and the number of myopes is still growing. In about 60% of cases, myopia is caused by a genetic elongation of the eye that is inevitable and cannot be reversed. Myopia is first diagnosed at the age of 4-6 years and continues to progress until the mid-20s. Up until now, there is no effective way to stop myopia progression due to continuing eye elongation. ZEISS has now developed a new and breakthrough myopia control spectacle lens for kids, that reduces myopia progression by 30%*. It provides dear and sharp vision and it retards myopia.
lt’s tailor-made for specific needs of myopic kids with extra thin & light plastic lenses: excellent wearing comfort, good looking and easy to handle. It’s been tested on, and accepted by, myopic children.
Watch this video to learn more about ZEISS myovision lenses. For a Myovision consultation, contact one of our eye doctors near you.
To view objects at distance (greater than 20 feet or 6 meters), the visual system causes the focus mechanism of the eye to un-focus or relax. When looking at near, the vision system causes the lens of the eye to accommodate to focus on a near point. This accommodation is achieved by increasing the convexity of the lens of the eye. Accommodation is the process of moving the distance point of focus on the retina to the near point of focus by increasing or decreasing the convexity of the lens of the eye. To look at it in a different light (no pun intended) accommodation is the process of moving a distance point of focus to a near point of focus by increasing convexity of the lens. Spasm of accommodation, or pseudo-myopia occurs when the convexity achieved for the near point of focus “locks in” and won’t release again to view distance objects clearly. An example of “locking in” is seen in college students. Many patients in their late 20s and early 30s report having had perfect vision until sometime during or immediately after their college years. The first change they note in vision was blur at distance after reading, studying or hours of computer work. They report looking up from a book after a study session, then blinking a few times or squinting to see far away again. There far away vision gradually returned, but slower and slower until the distance vision was slightly blurry permanently. Then, going for an eye exam where the chief complaint they tell the doctor is distance blur, they are prescribed eyeglasses for distance, see better and become dependent on the glasses, but the whole time the near problem was never addressed. So, their vision blurs at distance, is tweeked in an eye exam and the problem continues. If the student had only told the doctor that the problem was the change in focus from distance to near, they may have been prescribed glasses to help them focus at near (reading or computer glasses). That may have solved the problem and halted a problem that gradually leads to a need for glasses at distance full time.
Clearing someone’s distance vision is a no-brainer for your eye-care professional. You could leave a patient alone in the examination room with the ‘better #1 or better #2 machine’ and within 5 minutes they could find a prescription that could clear the bottom line of the eye chart. The person determines whether 1 or 2 is better at distance, gets shown to the optical and another nearsighted person is created. The problem was not at distance, but at near. The blur is not the consequence of continued development of the visual system. It is the first sign of visual change secondary to false distance blur, or Pseudo-myopia. People concentrate on print or virtual pixel images 16 to 19 inches in front of their nose for hours on end. After focusing at near for extended periods of time, the focusing system may lock in on the near image. When the person looks up, the distance image appears blurry. The neurological signal to focus for near is not letting go and blur is caused by looking at the distance object through the near focus. The person is looking far away, but their eye hasn’t let go the focus from the book or computer screen! The person is unable to relax accomodation for near back to distance. When they go for an eye exam, often distance glasses are prescribed. Distance glasses clear blur, but the problem of near over-focus remains and the cycle of annual prescription changes and increases continues. If the near point vision problem is not addressed, the progression of pseudo-myopia will eventually lead to more dependence on the distance prescription. Real doctoring involves identifying the cause of the changing vision and making recommendations to slow the vision changes down, stop them or reverse them.
In the 1960s, the first rigid contact lenses were brought to market. These lenses were made of a plastic impermeable to oxygen, polymethylmethacrylate (PMMA). The introduction of these lenses marked the first time that the public was mass marketed a vision correction product other than eyeglasses. After a few years of fitting these lenses on patients, optometrists noted interesting differences in wearers of PMMA lenses compared to eyeglass wearers. Certain patients fit in the PMMA lenses demonstrated slower rate of myopia progression, in some cases a total halt, while some patients reported that, for a certain amount of time after they removed the lenses they could see better. In some cases those people reported not having to wear glasses or contact lenses for many hours after removing the lenses. Doctors attributed these effects to wearing of PMMA lenses that were fit flatter than the curvature of the cornea. It appeared that lenses fit flatter than the curve of the cornea exert a gentle pressure on the cornea, causing the cornea to temporarily take on a slightly flatter shape and remain molded that way for a certain period of time after the lens was removed. While that would explain seeing better after removing the lenses, (flatter corneas experience less blur from myopia) the phenomenon of stabilization remained a mystery until only recently, when scientists and doctors began to suspect that peripheral refraction played a role in controlling the worsening vision people with myopia undergo. In the 1970s, gas permeable plastics were introduced and gradually replaced the PMMA lenses as gas permeable lenses were healthier for the eye. Myopia is defined by the Merriam-Webster dictionary as a condition in which visual images come to a focus in front of the retina of the eye resulting especially in defective vision of distant objects. The most frequent cause of myopia is an excessively long eyeball in terms of its axial length. The cause of an eye growing excessive in length has been the subject of much research and debate. Growth of the eye occurs in the sclera, or hard white shell of the eye. Studies suggest that sclera growth in human eyes is controlled by the clarity of the image received by specific areas of the retina. When the sclera grows, the position of the retina is changed in relation to where the image of the object being viewed falls within the eye. To change, it must either remodel or stretch.
The growth of the sclera that surrounds the center of the retina (Macula) is an important variable for keeping the axial length of the eye concurrent with the image being transmitted towards it. In eyes that are myopic (eyes with hyperopic peripheral refractions) more scleral expansion is expected, which also moves the macula in the myopic (nearsighted) direction. Changes in axial eye growth therefore produce changes in the shape of the globe resulting in changes in peripheral refraction.
Light that enters the eye closer to the center of the eye is focused on or close to the macula, or area of the retina responsible for sharpest vision. The light that enters the eye concentrically outward of the center of the cornea gets focused on areas of the retina peripheral to the macular region, hence the term peripheral refraction. The shape of the eye may be an important indicator for people at risk for progressive myopia. Myopes tend to have higher relative peripheral hyperopia, meaning that as the prescription of their eye is measured from the center of the eye towards the periphery, it gets “lower” i.e. the numbers decrease.
Research suggests that altering peripheral refraction may be a key in the management and stabilization of progressive myopia. It is believed that inducing myopic defocus in the periphery in myopic children is effective in stabilizing refractive change. There are optical and mechanical ways of inducing myopic defocus. Mechanically, the shape of the cornea can be altered by refractive surgery such as LASIK or PRK, or by “molding” with a standard gas permeable lens or an Orthokeratology (OrthoK) lens. Optically one can wear a new type of soft contact lens that attempts to alter the peripheral refraction of the eye.
On 25 March 2010, Scientists from the Vision Cooperative Research Centre (Vision CRC) in Australia announced that myopia, or short-sightedness, can be controlled with new technology. This ground breaking discovery was based on research conducted by Vision CRC partners – the University of Houston College of Optometry and the Brien Holden Vision Institute, located at the University of New South Wales.
Successful basic research on the nature and cause of myopia has led to the discovery that the peripheral retinal image plays a major part in stimulating eye growth and myopia. Large scale clinical trials testing both spectacles and contact lenses designed to control the position of the peripheral image and involving over 500 children in China and Australia, have produced promising results.
With myopia, instead of a distant image being focused on the retina, as it needs to be for clear vision, it is focused in front of the retina. Myopia often occurs when children commence school (ages six to seven), and if left undetected the condition progresses and can adversely impact the child’s education and social development.
Professor Brien Holden, CEO of the Vision CRC, explained further, “For hundreds of years focusing defects of the eye have been corrected by simply moving the visual image backwards and forwards with spectacle lenses. Professor Earl Smith from the University of Houston College of Optometry, has demonstrated that if we move the central image onto the retina but leave the peripheral image behind the retina, the peripheral image can drive the eye to elongate, causing myopia to increase.”
“The beauty of this new technology is that it addresses this problem by bringing the peripheral image forward, onto or even in front of the retina, and at the same time independently positioning the central image on the retina giving clear vision.
“The commercialisation of this technology is a most important outcome for the CRC program because of the potential vision and eye health benefits,” Professor Holden said.
Professor Holden announced that the breakthrough technology has been licensed to Carl Zeiss Vision (CZV) and developed into the first spectacle lens of its kind through a joint project with CZV lens designers. This new spectacle lens will be launched under the ZEISS brand name throughout Asia from April of this year. The Vision CRC has also licensed its myopia control technology to CIBA VISION for contact lens applications. Professor Holden added, “Myopia can be a serious eye condition. High myopia significantly increases the risk of cataract, glaucoma, and retinal detachment, all potentially blinding conditions and the public health risk is significant.” Dr Padmaja Sankaridurg, Head of the Myopia Program at Vision CRC, emphasised the nature of the new technology’s appeal. “Our unique lens designs act to curve or shift the peripheral image forward, thereby removing the stimulus to axial elongation and myopia progression,” she said. “We are continuing testing in Chinese and Australian children and young adults. So far, the trials have found that the first spectacle lens prototypes based on this new technology slow the rate of progress of myopia by 30% in children six to 12 years of age, where the child has a history of parental myopia,” she said. Professor Smith, from the University of Houston, commented, “Evidence shows that the number of individuals with myopia will dramatically escalate with increasing urbanisation and less outdoor activity”. “As urbanisation has increased in China, the prevalence and average amount of myopia has also increased. Recent evidence indicates that similar trends are occurring in the US and Australia. This ongoing epidemic of vision loss is associated with spiralling health and social costs, especially in many developing countries where over 80% of children have no correcting spectacles or contact lenses,” he said. “This new technology is not just for children either. Over 25% of myopes in the Western world are adult-onset myopes, which often begins at University. We believe that this technology has potential benefits for all myopes,” Professor Smith said.
Corneal reshaping therapies with gas permeable lens technologies may be helpful when seeking to improve eyesight in children, and reduce change in vision, specifically myopia in children and may, in some cases reduce the risk of children with myopia advancing to high myopia. If you are interested in managing your vision or the vision of a loved one with nearsightedness and concerned about vision changes, please contact one of our eye doctors near you or read through our website to learn about other options for improving your eyesight.
Orthokeratology lenses are FDA approved medical devices that, when properly maintained, may be worn with minimal risk of eye infection and inflammation. Proper maintenance of Orthokeratology lenses involves using appropriate device cleaning and care systems. Certain systems are appropriate for certain devices, so be sure to ask your doctor which system is best for your child’s devices. Common Orthokeratology cleaning systems include:
- Boston Advance
- Lobob System
- Opti-Free GP Multi-Purpose Solution
- Barnes-Hind Comfort Care
- Bausch & Lomb Wetting and Soaking Solution
- Clear Care Solutions
- DO NOT use Boston Simplus
Tap water, while clean enough to drink poses certain risks when used to rinse, clean or store Orthokeratology devices. We strongly recommend your devices and device storage containers not come in contact with standard tap water, distilled water or bottled water. Should the lens come in contact with water and be used overnight, the risk for a serious eye infection called Ancanthamoeba may result.
Rinsing of cleaning solutions off of lenses should be performed with sterile contact lens salines. Be sure not to let the dropper tip touch any surface, or the entire bottle becomes contaminated.
Steps for cleaning:
Your cleaning kit should contain (1) a cleaning solution (2) a soaking/rinsing solution (3) a clean storage case and possibly (4) eye drops for rewetting the devices while in the eye. The eyedrops are for use with standard rigid gas permeable (RGP) lenses and should not be put in your childs eye while wearing lenses.
STEP 1 – CLEANING WITH CLEANING SOLUTION
This solution is a very mild abrasive and is used in conjunction with finger-rubbing to dislodge and remove debris from the lens surface. The cleaner is in suspension, so shaking it is necessary before use. Dispense 2-3 drops of cleaning solution into the palm of the hand and place the Orthokeratology device in the palm. Without too much pressure, gently massage the cleaning solution across both surfaces of the lens for approximately 1 minute. Most solutions start out clear and foam up as you clean. To ensure you have cleaned long enough, the foam should be milky white and thick when finished.
The concave side of Orthokeratology lenses has a circular “edge” which can be challenging to clean. The front side is spherical and smooth and easily cleaned, but rubbing with finger tip pads isn’t always sufficient to dislodge and remove debris from within this “edge”. Spending extra time rubbing with the cleaning solution on the concave side of the lens is recommended, or one may use a q-tip soaked cotton applicator to clean the concave side to ensure debris comes out of the “edge” of the lens.
STEP 2 – RINSING CLEANING SOLUTION OFF THE DEVICE
Once the device has been cleaned manually with cleaning solution, it is important to remove the abrasive cleaner from the device before putting the device in an eye or back in it’s case. It is a good idea to wash the cleaning solution from the previous step off your palms before proceeding to rinse the cleaning solution off the device.
Obtain sterile saline from a pharmacy, drugstore or other retail store. Place the device in the palm of the hand and use a strong stream of saline by squeezing the bottle firmly to rinse each side of the device. Be sure to pull the stopper up in the sink or lay a paper towel over the drain so the device isn’t accidentally washed out of your palm and down the drain during the rinsing process.
STEP 3 – STORING THE DEVICE
Using a clean storage case, fill it with the soaking solution and place the newly cleaned lens in the case. The case MUST be a screw-down plastic case – the sample cases given in the doctors office that are press-down are only temporary cases and should not be used more than one day.
PROCEDURES FOR USE
Orthokeratology devices are worn during sleep. To achieve maximum effect, at least 8 hours of sleep is required. More than 8 hours has no additional benefit as 8 hours should be sufficient to achieve results. A clean Orthokeratology device should be removed from the case after 5 minutes of hand washing with anti-bacterial soap. Do not rub the eyes when the devices are on.
Inserting and Sleeping With Orthokeratolgy Devices
Upon insertion, the child should be directed to go directly to sleep. Wearing the Orthokeratology devices while awake for more than a few minutes is not recommended and has resulted in eye irritation, discomfort and small abrasions that can lead to other temporary problems wearing the devices. When the eyes are open, Orthokeratology devices are often described as anywhere from “itchy” to “irritating”. When the eyes are closed, while there may be some “awareness”, it is generally not described as discomfort. It is normal to experience some type of discomfort for the first 2 weeks, which gradually dissipates from day 1 to day 14. Any irritation that remains when the child’s eyes are closed after 2 weeks should be reported to the doctor. The case should be emptied of soaking solution, dried with a clean paper towel and wiped with an alcohol wipe in the well where the lens was stored as well as on the screw-down cap and around the threads on the case that the cap screws onto. After the alcohol rub-down, the case and cap should be stored upside down on the paper towel to minimize risk of contamination. DO NOT screw the cap on the empty case; the potential of creating a dark, moist, air-free environment within the case that encourages colonization of bacteria is enhanced by cleaning and shortly thereafter sealing the case by screwing the cap on.
Awakening After Wearing Orthokeratology Devices
In the morning, the child should make their way to the bathroom, wash their hands for several minutes with antibacterial soap, pull the stopper in the sink or lay down a paper towel over the drain and remove their devices. The devices should be cleaned according to the procedure outlined in steps 1 and 2, the case filled with fresh storage solution and put into the case in the storage solution with the appropriate lens for each eye in the side of the case labeled “L” for left or “R” for right. The case lids should be screwed down.
- Never rinse devices or cases with tap or bottled water. Water should never come in contact with either.
- Patients are instructed never to wear their devices while in the presence of noxious substances.
- Do not use hairspray around the devices.
- Do not use Boston Simplus cleaner.
- Do not get alcohol on the devices.
- Do not let the devices touch non-sterile surfaces other than the contact lens case contents.
- Do not wear the lenses for any significant period of time with your eyes open.
- Do not let pain or pain accompanied by sensitivity to light go unchecked by the doctor.
- Do not neglect to keep the contact lens case clean as recommended.
- Do not touch the dropper tip of your cleaning and solution bottles to anything.
- Do not use any solutions or eyedrops in conjunction with wear unless discussed with your doctor.
- Do not neglect your annual examination and Orthokeratology check-up; lenses that are slept in pose certain risks and eyes using Orthokeratology must be monitored annually. This is imperative.
Common complaints during and subsequent to the initial few weeks of therapy with Orthokeratology include eye redness, itchiness, irritation, vision challenge under low illumination and discharge (mucous) from the eye or coating the lens. Most of these conditions will resolve themselves, however, any ongoing concern should be brought to the attention of the doctor. Pain accompanied by redness, sensitivity to bright lights, discharge (mucous) or a combination of any two or more of these symptoms must be evaluated by a doctor.
Redness in and of itself is not a sign of a problem with Orthokeratology or a problem with the eye caused by the therapy. It is common for an eye to appear red in the morning for up to an hour or two after using Orthokeratology devices. Redness combined with pain and/or sensitivity of light is a problem that should be taken to the doctor that day. As Orthokeratology is worn over greater amounts of time, redness tends to decrease.
Most Orthokeratology devices cause itchiness or awareness when the eyes are opened. This is due to the motion of the eyelid back and forth over the lens. When the eyelid is closed as it is supposed to be for Orthokeratology device wear, itching is supposed to subside. If the lens is itchy or causes awareness with the eyelids closed, inform your doctor. In some cases, eye allergies may be magnified through use of Orthoerkeratology devices. If this happens to your child, we recommend treatment with a prescription allergy eye drop in conjunction with the Orthokeratology therapy. If this alone doesn’t work, in rare cases we have recommended the child stop wearing the therapy devices during their allergy season.
TRANSIENT VISUAL BLUR
When overnight corneal reshaping lenses dislocate during sleep, transient distorted vision may occur the following morning after removal of the lenses. This distortion may not be immediately corrected with spectacle lenses. The duration of distorted vision would rarely be greater than the duration of the daily visual improvement normally achieved with the lenses.
Mild to Moderate Irritation or Awareness
Mild to moderate irritation or awareness is common during the early stage of Orthokeratology therapy and not of concern generally. It is expected that a person is aware of these devices when the eye is open and ultimately there should be no sensations when the eye is closed. Over time, the eye adapts to the device and irritation and awareness subsides; this usually occurs over a period of 2 weeks, irritation and awareness lessening linearly during that time. Sometimes using a doctor recommended eyedrop can help to minimize the irritation or awareness. It is possible that irritation or awareness are caused by external factors such as (1) an device not cleaned well (2) a broken device (3) A foreign body like an eyelash or fuzz from a paper towel lodged between the eye and the device, (4) dust (5) other environmental factors. Once these factors have been ruled out as a cause and the lens has been worn for a few weeks, report any additional closed-eye irritation or awareness to your doctor. Patients are instructed to remove the devices if they experience sharp pain that lasts more than a few minutes, extreme sensitivity to light or ongoing foreign body sensation that persists after the lens has been removed from the eye.
Vision Challenged Under Low Illumination
The way in which the optics of the eye are altered by flattening the cornea with Orthokeratology devices may result in vision challenges under low illumination, specifically night vision. This is a common side effect that reverses itself once Orthokeratology is discontinued. It is not a medical concern and never permanent. In some cases, it might indicate a slight “under” correction, meaning that a lens change may improve it slightly, but in most cases people who experience this should understand it won’t go away, while daytime vision and indoor vision in most cases should be excellent.
Sometimes the eye responds to having a foreign body in it by increasing secretion of mucous. It is common to have mild to moderate mucous production from wearing Orthokeratology devices in the first 2 weeks. The mucous production should be bilateral i.e. occur in each eye. Mucous that occurs in one eye only may need to be evaluated by the doctor as it might be a sign of an infection. Allergy sufferers will produce more mucous and the mucous will occur in both eyes. Mucous producers should pay closer attention to lens cleaning and may have to clean more vigorously to get their lenses clean. Copious production of mucous should be evaluated by your eye doctor.