Custom Contact Lenses
Custom contact lenses may be for you if you can't wear regular contact lenses because of problems such as an irregularly shaped eye or too much astigmatism.
You also might consider custom contact lenses if regular contacts are uncomfortable or cause vision problems.
Custom-made contacts are available both in rigid gas permeable (RGP or GP) and soft lens materials, and may be able to provide sharper vision and greater wearing comfort than regular GP or soft lenses.
Gas Permeable Custom Contacts
Most eye care professionals agree that gas permeable contact lenses generally provide sharper vision than soft contacts. This especially is true for people with certain types of astigmatism.
But some people find gas permeable lenses hard to wear. Traditionally, GP lenses have been designed with a slight gap between the edge of the lens and the eye's surface. This "edge lift" enables tears to flow behind the lens during and after blinks to provide more oxygen for eye health.
Unfortunately, the interaction between the edge of gas permeable lenses and the eyelid and the movement of GP lenses during blinks can make these lenses uncomfortable for some wearers.
Also, for individuals with unusually shaped corneas, it may be impossible to fit the eye properly with conventional GP lenses so the lenses remain properly centered on the eye. This increases the risk of discomfort and variable vision.
To overcome these limitations and enable more people to enjoy clear, comfortable vision with GP lenses, contact lens manufacturers are now using advanced technology to create customized gas permeable lens options.
The fitting and lens manufacturing process for gas permeable custom contact lenses differs from conventional GP lenses in two ways: how your eye is measured and how the lenses are designed.
Eye Measurements, Lens Designs for Conventional GP Lenses
Understanding how conventional GP lenses are fitted as part of a contact lens eye examwill help you understand the complexities of custom contact lenses.
Most eye care practitioners measure the curvature of the front surface of the cornea with an instrument called a keratometer.
The keratometer uses light reflections from the cornea to determine the steepest and flattest meridians of the eye. To picture how this works, imagine that the front of the eye is like the face of a clock. A line connecting the 3 and the 9 is one meridian; a line connecting the 12 and 6 is another meridian, and so on.
The curvature of a conventional GP contact lens is based on three keratometry measurements: the curve of the steepest meridian of the cornea, the curve of the flattest meridian and the orientation of the flattest meridian — in other words, whether the flattest meridian is horizontal, vertical or somewhere in between.
Based on these measurements, the eye care practitioner or lens manufacturer chooses the curves to apply to the back surface of the GP lens for the best possible fit. With a conventional GP lens, the back surface typically has one curve for the central part of the lens (called the base curve) and two or more flatter curves in the periphery of the lens.
These flatter curves help the lens align better to the surface of the cornea, which typically becomes flatter in the periphery. The peripheral curves also provide the proper amount of edge lift so tears can circulate behind the surface of the lens during and after blinks.
Eye Measurements, Lens Designs for GP Custom Lenses
Compared with conventional methods, the eye measurements and lens designs for custom gas permeable lenses are much more complex.
Instead of obtaining just three measurements of the cornea from a keratometer, the eye care practitioner who fits GP custom contact lenses uses an instrument called a corneal topographer to obtain curvature data from several thousand reference points on the eye.
Bifocal and Multifocal
Contact Lenses:Bifocal contact lenses are designed to provide good vision to people who have a condition called presbyopia.
The main sign that you're developing presbyopia is that you need to hold menus, newspapers and other reading material farther from your eyes in order to see it clearly.
Bifocal contact lenses come in both soft materials and rigid gas permeable (GP) materials. Some can be worn on a disposable basis. That means you have the convenience of throwing the lenses out at specified intervals (even daily, in some cases) and replacing them with fresh, new lenses.
Several lens manufacturers offer multifocal contact lenses made of silicone hydrogelmaterial. These lenses allow significantly more oxygen to reach the cornea than conventional soft lenses for greater wearing comfort, and are available for both daily wear and extended wear.
Brands of multifocal silicone hydrogel contacts include Acuvue Oasys for Presbyopia (Vistakon), Air Optix Aqua Multifocal (Ciba Vision), Biofinity Multifocal (CooperVision) and PureVision Multi-Focal (Bausch + Lomb).
Bifocal Contacts, Multifocal Contacts – What's the Difference?
Bifocal contacts lenses have two prescriptions in the same lens. Multifocal contact lenses have a range of powers (similar to progressive spectacle lenses) in each lens.
"Multifocal contacts" also is used as a catch-all term for all contact lenses with more than one power, including bifocal contacts.
How Multifocal Contact Lenses Work
Bifocal and multifocal contact lenses work in several different ways, depending on the design of the lens. The designs fall into two basic groups:
- "Alternating vision" (translating) lenses are so named because your pupil alternates between the two powers, as your gaze shifts upward or downward.
- "Simultaneous vision" lenses require your eye to be looking through both distance and near powers at the same time. Although this might sound unworkable, your visual system learns to select the correct power choice depending on how close or far you're trying to see.
Simultaneous vision lenses come in two types: concentric ring designs and aspheric designs. 
Left: In this example of a translating design the near power is on the bottom. The bottom edge is flattened to keep the lens from rotating on your eye when you blink. Middle: In this concentric design the distance prescription is in the center and is surrounded by rings of near and far power, but near-center versions also are available. Right: In this aspheric design the near and distance prescriptions are both in front of the pupil.Alternating Bifocal Contact Lenses
Alternating or translating bifocals work much like bifocal eyeglasses. They have two power segments, with an obvious line of separation between the distance correction on top and the near correction below. Your eye looks through either one or the other, depending on whether you're looking far or near.With bifocal eyeglasses, this mechanism works because the lenses stay in place even as your eye moves. That can happen with contact lenses, too. Since most alternating bifocals are GP lenses, they are smaller in diameter than soft lenses, and they ride on your eye above your lower eyelid. Therefore, when your gaze shifts downward, the lens stays in place, allowing you to see through the lower, near-correction part of the lens.Concentric Ring Designs
This type of bifocal contact lens features a prescription in the center and one or more rings of power surrounding it. If there are multiple rings, they alternate between the near and distance prescription.pupil area, but this varies as your pupil expands and contracts due to varying light.Concentric ring bifocal contact lenses can be made of either soft or rigid (GP) material. The locations of the powers will vary:- GP bifocals usually have the distance power in the center (called center-distance).
- Soft bifocal contact lenses usually have the near power in the center (center-near).
- Some soft multifocal designs are center-near on your dominant eye but center-distance on your non-dominant eye.
Aspheric Multifocal Contact Lenses
These multifocal contact lens designs work more like progressive eyeglass lenses, where the different prescriptive powers are blended across the lens. Unlike eyeglasses, however, aspheric contact lenses are simultaneous vision lenses, so your visual system must learn to select the proper prescription for the moment.This is the only type of multifocal contact lens that can be described as "progressive." It's also concentric, like the concentric ring designs, and it has become the most popular type of multifocal contact lens.Will Bifocal Contact Lenses Work for Me?
Bifocal contact lenses have been around for many years, but until recently they weren't very popular.Older bifocal designs didn't satisfy many people, leading to frustration among wearers and prescribers alike.Today, new technology has produced more successful designs, as well as a greater variety of designs. So if one design doesn't work for you, another might.Your doctor may also try these related techniques:- Monovision involves using single-vision lenses to put your near prescription on one eye and your distance prescription on the other.
- Modified monovision uses a single-vision lens on one eye and a multifocal lens on the other.
Disposable Contacts:
A Healthy Choice:Disposable contacts are worn for a specific period of time, then thrown out and replaced with fresh lenses. Disposables have become the most common type of contact lenses.Many eye care practitioners and consumers prefer disposable contacts for their health and convenience benefits.What Are Disposable Contact Lenses?
Contact lenses generally fall into these categories, based on how frequently they are replaced:- Disposable lenses: Replaced every two weeks, or sooner
- Frequent replacement lenses: Replaced monthly or quarterly
- Traditional (reusable) lenses: Replaced every six months or longer
The term "disposable" often refers to both disposable and frequent replacement lenses.
Are you following your eye doctor's cleaning instructions? If not, you might be better off with daily disposables.Replacement Schedule and Wearing Schedule
A common source of confusion about contact lenses involves replacement and removal intervals:- Replacement schedule refers to how often your lenses are discarded and replaced — that is, whether they are disposable, frequent replacement or reusable.
- Wearing schedule refers to how long you wear your contacts before removing them. "Daily wear" means you wear contacts only during the day and remove them each night. "Extended wear" means you wear them continually for two or more days, including during sleep.
Disposable contacts can be prescribed either for daily wear orextended wear, depending on your eye physiology and needs.Why Throw Out Lenses at All?
The more frequently you replace your contact lenses, the healthier and more comfortable your eyes can be.Protein, calcium, lipids and other substances found naturally in your tears can build up on your lenses. These deposits make your contacts less comfortable than when they were new, and can also make your eyes more prone to infection.Of course, lenses can be cleaned, but cleaning is not 100 percent effective. Some deposits will remain and continue to accumulate over time.Daily Disposables: The Ultimate in Convenience and Health
There are two ways to avoid just about all contact lens care. One is to wear extended wear lenses continuously for several days, and then discard them when you remove them. Unfortunately, overnight wear of contact lenses is not a good idea for everyone, and wearing contact lenses during sleep may increase your risk of eye problems.The other alternative is daily disposables, also called one-day disposables: contacts that you discard every night and replace in the morning with new ones.Many eye care professionals and contact lens wearers feel that daily disposable contacts offer the best of both worlds: They are convenient because no lens cleaning is required, and they are healthy because there is no day-to-day accumulation of lens deposits. Also, because these lenses are not worn overnight, you potentially have less risk of contact lens-related eye problems.How Different Are Disposables from Regular Lenses?
Even before the advent of disposable lenses, it was well known that frequent lens replacement was a healthy thing to do. Problem was, contacts were too expensive to discard very often — so various cleaning solutions and devices were used to prolong the life of the lens.Then contact lens manufacturers developed new manufacturing methods to produce high-quality lenses in greater volume, at lower cost. These advances led to lower lens prices, making it affordable to replace lenses more often.Some of today's disposable lenses are made of the same materials as traditional lenses; other disposables are made from new materials developed especially for disposability.How Much Do Disposable
Contacts Cost?The cost of being fitted with contact lenses varies widely, depending on where you live, the eye care practitioner you choose and how complicated your prescription is.The incremental cost of choosing disposable contacts over traditional contact lenses is slight and is somewhat offset by the reduced need for cleaning products.Even daily disposable lenses are more affordable than many people expect. If you buy a year's supply of the lenses, you can wear daily disposable contacts for little more than a dollar per day. Also, with daily disposables you'll eliminate the cost of lens cleaning products.Extended wear contact lenses may be the right option for you if you would like to wake up each day with clear vision.Contact lenses are available for two different wearing schedules:- daily wear (you remove them before sleeping)
- extended wear (you leave them in overnight)
In the United States, the FDA has approved some contact lenses for daily wear only and others for extended wear. Extended wear lenses allow more oxygen to reach your cornea.Most extended wear (EW) lenses today are made of silicone hydrogel lens materials that allow significantly more oxygen to reach the front surface of the eye, compared with earlier soft (hydrogel) lens materials.Several extended wear lenses are FDA-approved for up to seven days of continuous wear, and at least two brands of silicone hydrogel EW lenses — Air Optix Night & Day (CIBA Vision) and PureVision (Bausch + Lomb) — are approved for up to 30 days of continuous wear.Also, some gas permeable lenses have received FDA approval for up to 30 days of continuous wear.It's important to note that these are the maximum wearing schedules allowed. Many people cannot tolerate wearing EW lenses for this length of time, and some people's eyes cannot tolerate any overnight wear of contact lenses. During your contact lens fitting and follow-up, your optometrist or ophthalmologist will advise you whether you can wear EW contacts overnight and how many days of continuous wear your eyes can tolerate.Recently, an international survey of contact lenses prescribed for extended wear in 2006 to 2010 found that:- 71 percent were spherical lenses to correct nearsightedness or farsightedness.
- 14 percent were toric lenses for astigmatism (with or without nearsightedness or farsightedness).
- 10 percent were multifocal lenses for presbyopia.
The same survey found that the majority of extended wear lenses (66 percent) were designed for monthly replacement; approximately 18 percent were for 1-2 week replacement.Risks of Extended Wear Contacts
The FDA first approved certain contact lenses for overnight wear in 1981. These lenses were approved for up to two weeks of wear without removal. Shortly thereafter, some lenses received FDA approval for up to 30 days of continuous wear.
Researchers found, however, that the incidence of eye infections was greater among people who slept while wearing contact lenses. In response, the FDA changed the maximum extended wear period to seven days.However, many eye care practitioners decided that any overnight wear was too risky, and they began encouraging patients to always remove their contacts before sleep, even if the lenses were FDA-approved for extended wear.Extended wear lenses are a concern because bacteria and other potentially dangerous microorganisms can adhere to the lenses and get trapped between the lenses and your eyes. These microbes thrive in the warm, moist environment under your contact lenses, especially when your eyelids are closed during sleep. And because contact lenses reduce the oxygen supply to your corneas, your eyes are less able to fight off infections.Contact lens-related infections can range from an annoying case of pink eye to more serious conditions such as Acanthamoeba keratitis and fungal eye infections that can cause permanent vision loss. If you wear contacts continuously for several days, your risk of these problems increases significantly.New Extended Wear Lenses
Advances in contact lens technology have made new extended wear contact lenses safer than previous lenses prescribed for continuous wear.Also, eye care practitioners generally are taking a more cautious approach to patient selection and wearing recommendations to reduce the risk of eye problems from continuous wear of contact lenses.These advances and new approaches to extended wear include:- Most modern extended wear lenses are now made with silicone hydrogel lens materials that allow significantly more oxygen to pass through the lenses to the eye than previous EW lenses.This decreases the risk of hypoxiathat makes the cornea more susceptible to inflammation and infection.
- Nearly all soft lenses prescribed for extended wear today are disposable contacts that are discarded at two-week or monthly intervals. More frequent replacement of EW lenses reduces the build-up of proteins, lipids and other lens deposits that cause eye inflammation and discomfort and create a hospitable environment for the growth of infection-causing microorganisms.
- Extended wear lenses also are available in new rigid gas permeable (GP) lens materials. Some eye care practitioners prefer GP lenses for extended wear because they cover less of the eye and, because they move more with each blink than soft EW lenses, there is less risk of debris and infection-causing microbes getting trapped behind the lenses.
- Many eye care practitioners are recommending "flexible wear" of extended wear contacts rather than wearing the lenses continuously for several days without a break. In flexible wear, disposable EW lenses usually are removed at night before sleep, but can be worn overnight occasionally — during a weekend camping trip, for example, or for daytime naps. Though flexible wear is not quite as convenient as extended wear (proper lens care using an approved contact lens solution is required each time the lenses are removed), it may be less risky than full extended wear.
Extended Wear Safety
Despite these improvements, wearing contact lenses during sleep still carries a greater risk of complications than removing your lenses daily. For this reason, most eye care practitioners prefer daily wear lenses for their patients.
In a study of contact lens fittings by eye care professionals in 39 countries over a 14-year period ending in 2010, researchers found that use of EW contact lenses peaked in 2006, when approximately 12 percent of all soft contact lens prescriptions were for extended wear lenses.In 2010, approximately 7.8 percent of worldwide contact lens fittings were for extended wear lenses. The rate was highest in Norway, with 27 percent; in the United States, EW lenses accounted for about 10 percent of soft contact lens fittings.The reason for the decline in use of extended wear lenses from 2006 to 2010 might be due in part to increased use of daily disposable contact lenses. These daily wear lenses are removed and discarded each night before sleep, and (like disposable extended wear lenses) they offer the convenience of not requiring daily cleaning and disinfection with contact lens solutions.Also, some candidates for extended wear contacts are instead choosing LASIK and other types of refractive eye surgery to eliminate their need for prescription eyeglasses and contact lenses.Eye infections and other complications of contact lens wear often are caused by failure to clean and disinfect the lenses after each use. You can bypass the need for daily lens care by wearing extended wear contacts continuously, but it's critical to discard your lenses as instructed by your eye doctor and not exceed the maximum wearing schedule your doctor recommends.Usually this means replacing your lenses weekly, every two weeks or monthly (depending on the type of lenses you have), and sleeping without your lenses on at least once a week.Keep in mind that exposure to smoke, wearing your contacts while swimming or relaxing in a pool or hot tub, dry eyes and previous eye irritations or infections are additional risk factors for extended wear contact lens complications.Another way to avoid a problem with extended wear lenses is to "listen" to your eyes and take action, if necessary. Every day, take a good look at your eyes in a mirror. They should always:Monovision With Contact Lenses:
The onset of presbyopia can be frustrating if you wear contact lensesand want to continue seeing clearly up close without reading glasses.One solution is to have your eye care practitioner perform a monovision contact lens fitting. Monovision with contacts can reduce your need for "readers" and is an especially good option if you are not a good candidate for bifocal contacts.How Monovision Works
With monovision, you wear a contact lens on one eye to correct your distance vision and a contact lens on your other eye to correct your near vision. The lens for distance vision is usually worn on your dominant eye.With monovision, the eye that sees well for distance vision will be slightly blurred up close and the eye that sees well up close will be slightly blurred when looking at distant objects. But with both eyes open, typically the result is acceptably clear and comfortable vision at all distances.Therefore, the term "monovision" is somewhat misleading. The two eyes still work together as a team to see clearly at all distances; it's just that one eye is clearer than the other, and the "stronger eye" will depend on whether you are looking at something far away or up close.Though monovision might sound difficult to adjust to, most people adapt very well and eventually don't even notice which eye is their "distance eye" and which is their "near eye."Variations of Monovision
Depending on your daily visual demands and how you respond to monovision with contact lenses, your eye doctor may recommend a variation of monovision to best suit your needs. These variations include:- Mini-monovision. In this variation, a less-than-typical magnifying power is added to the near vision lens. Mini-monovision often is an excellent solution for people who find that standard monovision does not give them the sharp distance vision they desire, and they don't need to do a lot of close-up work (or they don't mind wearing reading glasses on occasion). A good example is someone who spends much of their day driving and little time working on a computer or reading, but wants to be able to read a menu withoutprescription glasses.
Though a person with mini-monovision may need reading glasses more than someone who has standard monovision, he or she will be less dependent on readers than a person wearing distance contact lenses in both eyes. - Modified monovision. In this variation, a single vision contact lens is worn on the distance eye and a bifocal contact lens is worn on the near eye. Modified monovision, like mini-monovision, can provide sharper distance vision than standard monovision, while still providing acceptable near vision without reading glasses for many close-up tasks.
The distance power of the bifocal lens also can be adjusted to provide sharper vision at arm's length for tasks such as computer work.
The Limitations of Monovision
The downside of monovision is that some people find it compromises the clarity of their distance vision too much, making distant objects appear slightly blurred. Others find monovision doesn't provide adequate near vision to give them the freedom from reading glasses they were hoping for.Also, although the two eyes still work together as a team in monovision, binocular vision is slightly compromised, which can cause a slight decrease in depth perception.Cost of Monovision Contact Lenses
In standard monovision and mini-monovision, conventional single vision contact lenses — including disposable contact lenses — are used. Because these are less expensive than multifocal contacts, lens replacements will cost less. Even modified monovision will save you money on lens replacements, since a bifocal contact lens is worn only on the near eye.But fitting monovision contact lenses is more complex and generally takes more office visits than a regular contact lens fitting. This is because even slight changes to the contact lens power on either eye in monovision can make a significant difference in the wearer's visual satisfaction, and each modification of lens power should be followed by several days of lens wear to see how you adapt to the change.Therefore, the fitting fee for monovision usually is significantly higher than a standard contact lens fitting. Many eye care professionals charge the same for monovision contact lens fittings as they do for bifocal contact lens fittings. This may be roughly twice the fee for a standard contact lens fitting or more.Surgical Monovision Options
Monovision also can be accomplished with surgery for presbyopia, including LASIK,conductive keratoplasty (CK) and other corneal or lens-based refractive surgeries adapted for presbyopia correction.Prior to any surgical monovision correction, it's smart to "test-drive" the concept with contact lenses beforehand. Generally, a two-week period of wearing monovision contact lenses will give you a good idea of how well you will do with permanent surgical monovision.For more information about the pros and cons of monovision versus bifocal contact lenses for your particular visual needs, see your eye doctor for a consultation and possible trialOrthokeratology:
Reshaping Your Eyes
With Contact Lenses:Wouldn't it be great if you could correct your nearsightedness and reduce your dependence on glasses or contact lenses — without having to undergo eye surgery?It might sound far-fetched, but it's a reality for many people. It's called orthokeratology, or ortho-k, and it is available throughout the country.Ortho-k is not new: It has been performed for decades by eye doctors who specialize in contact lens fitting. Interest in orthokeratology has increased in recent years due to advances in ortho-k technology and a desire among many people for a non-surgical alternative to LASIK and other refractive eye surgery to correct their nearsightedness.How Ortho-k Works
Orthokeratology is the design and fitting of special gas permeable contact lenses that gently reshape the clear front surface of the eye (cornea), so you can see clearly even after you remove the lenses.Myopia (nearsightedness) is caused by the cornea being too steep. Ortho-k, like LASIK, reshapes the cornea so light entering the eye is more accurately focused on the retina.Unlike LASIK, however, the corneal reshaping effect of orthokeratology is temporary — generally enough to eliminate your need for glasses or contacts for a day or so. Then you have to wear the ortho-k lenses again to maintain the proper corneal shape.Overnight Ortho-k: Corneal Reshaping While You Sleep
In June 2002, the FDA granted approval to Paragon Vision Sciences for overnight corneal reshaping called Corneal Refractive Therapy (CRT). Approval of overnight wear of corneal reshaping lenses has made ortho-k much more convenient and has led to a recent surge in its popularity. With overnight ortho-k, all corneal reshaping takes place while you sleep, and "retainer" contact lenses no longer have to be worn during the day to preserve good vision.Currently, two brands have FDA approval for overnight corneal reshaping: Paragon CRT (Paragon Vision Sciences), and Vision Shaping Treatment (Bausch + Lomb). Both are fit only by eye care practitioners who have been through each company's certification procedure.In February 2012, Wave Contact Lens System announced its custom gas permeable (GP) lens designs for orthokeratology were approved for overnight wear under the Bausch + Lomb Vision Shaping Treatment (VST) program.Wave's ortho-k lenses are custom-designed directly from the patient's corneal topographydata and each lens contains hundreds of lathe-cut curves to closely match the shape of the cornea for optimum lens centration and comfort during corneal reshaping, according to the company.Sometimes, eye care professionals use other brands of extended wear GP contact lenses for overnight ortho-k as an "off-label" use at the doctor's discretion (see sidebar).Who Is a Candidate?
Orthokeratology is for people of any age who are nearsighted.The FDA has approved Paragon CRT corneal refractive therapy lenses for the treatment of up to -6.00 diopters (D) of myopia; VST overnight ortho-k lenses are approved for up to -5.00 D.Astigmatism also can be treated: up to -1.75 D with Paragon CRT, and up to -1.50 D with VST.Many doctors believe the best candidates for ortho-k are people who have no more than -4.00 D of myopia and little or no astigmatism.Non-surgical corneal reshaping with contact lenses can be performed on people of any age, as long as their eyes are healthy. Ortho-k holds particular appeal for people who participate in sports, or who work in dusty, dirty environments that can cause problems for regular contact lenses.Because ortho-k offers similar benefits to LASIK, it's also appealing to adolescents and teens, who are not eligible for LASIK. However, there are some concerns about corneal infections in young people who are fitted with ortho-k lenses, so it's wise to discuss this with an eye care practitioner who is experienced in treating this age group.What Results Can You Expect from Ortho-k?
Eye care practitioners usually aim for 20/20 vision after ortho-k and corneal refractive therapy, but 20/40 vision (the legal minimum for driving in most of the United States) typically is considered acceptable.In the FDA clinical study for approval of Paragon CRT lenses, 93 percent of patients achieved 20/32 vision or better, and 67 percent achieved 20/20 or better. In the clinical study for FDA approval of one VST design, about 95 percent achieved 20/40 or better, and 73 percent achieved 20/20 or better. Both studies followed patients over at least a nine-month period.What to Expect When You Begin Ortho-k
The eye doctor will begin by measuring the curvatures of your corneas using an instrument called a corneal topographer — a painless procedure that takes about a minute and produces a topographical map of your eye's surface.Your doctor might use an in-office inventory of lenses for fitting your eyes with ortho-k lenses the same day corneal topography measurements are taken, or he or she may order custom ortho-k lenses for fitting at a later date.You may need a series of temporary lenses to see properly until you reach the desired prescription. "My goal is one pair of lenses for each patient," says Marjorie J. Rah, OD, PhD, of the New England Eye Institute. "But for the most part, I'm using two pairs of lenses."How Long Does Ortho-k Take?
Ortho-k can reshape two to three diopters of myopia in two weeks or less, says Dr. Rah.During the time your eyes are being reshaped, you can experience side effects. "In the beginning, you'll have glare and halos that will be reduced with time, but may never completely go away," says Dr. Rah. "As with LASIK, patients with large pupils are especially susceptible to this."Once your eyes reach the desired prescription, you will need to wear lenses when you sleep or during part of the day to maintain your prescription. Discontinuing lens wear altogether allows your corneas to gradually regress to their original shape or close to it.Is Ortho-k Comfortable?
Some people have comfort issues with daytime wear of gas permeable contacts (also known as GP, RGP or "oxygen permeable" lenses), which are used for ortho-k.With GP contacts, a sensation of lens awareness can result from interaction of the eyelid with the edge of the lens during blinking. (This doesn't happen with soft lenses because they are larger and remain tucked under the eyelids.) But when ortho-k lenses are worn during sleep, blinking and lens awareness generally are not a problem.Cost of Ortho-k
Fitting ortho-k lenses takes more of a doctor's time than fitting regular contact lenses. It requires a series of office visits and potentially multiple sets of lenses. Each eye care practitioner determines his or her fee for orthokeratology, which is based both on time and lens costs.According to industry sources, ortho-k on average costs $800 to $1,500 for both eyes, which is roughly half the cost of LASIK. This does not include the cost of replacement lenses.Ortho-k cost can vary based on the region of the country, urban vs. rural settings, and the type of practice. Normally, orthokeratology is not completely covered by vision care insurance plans.Should You Have Ortho-k Instead of LASIK?
Ortho-k works best for people who don't want to wear glasses or contact lenses all day, every day — but don't mind wearing contact lenses at night, or occasionally during the day.If your primary goal is to reduce your dependence on glasses or contacts during the day, then ortho-k might be a good alternative for you. However, if you want to eliminate the bother of contacts altogether, then corneal refractive therapy is not likely to satisfy you.Ortho-k may be a good option if you suffer from dry eyes. It's been found that this condition sometimes is worsened by LASIK.Unlike LASIK, ortho-k is reversible. If you try reshaping lenses and later decide you want laser eye surgery instead, you can do that. But you will have to discontinue wearing the lenses and wait a period of time before surgery (possibly several months) to allow your corneas to fully revert to their natural shape.As with all contact lenses, there are some possible side effects and complications of wearing ortho-k lenses.
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