Ortho-K Lens

What is Ortho-K Lens?

Despite the fact that eyeglasses and standard contact lenses have been shown to treat nearsightedness, farsightedness, and other visual issues. Some people may always prefer the flexibility and comfort of not wearing corrective glasses during their everyday activities. While many people are ready to pursue long-term remedies such as laser surgery, others want a less intrusive, more reversible approach.

Orthokeratology, or ortho-k, is the temporary reshaping of the cornea with specifically designed and fitted contact lenses to improve eyesight. It's similar to orthodontics for your eyes, and the procedure is frequently likened to dental braces. The majority of ortho-k lenses are used at night to reshape the front surface of the eye while you sleep. Vision improvements are reversible, but they can be sustained if the lenses are used as prescribed.

Ortho-K lenses (orthokeratology lenses) are gas-permeable lenses that are used to reshape the cornea. The patient wears the lenses overnight, and when they remove them in the morning, they will have good vision for the rest of the day without the need for glasses or daytime contact lenses. Ortho-K lenses can treat a wide range of vision problems, including astigmatism, myopia (nearsightedness), and hyperopia (farsightedness).

A variety of companies manufacture orthokeratology lenses, which all employ unique gas-permeable contact lenses to reshape the cornea. The lens material, particularly its oxygen permeability as evaluated by the 'Dk' rating (the higher the number, the greater the degree of oxygen permeability), is critical for sustaining eye health throughout therapy. Materials and processes differ around the globe, as does country approval. For example, "Menicon Z Night" lenses are often used just overnight, but in the United States, they are also FDA-approved for up to 30-day usage on a regular GP schedule.

Some practitioners have also created their own orthokeratology lenses, often by combining corneal topography data with their own knowledge and experience to establish the optimal lens characteristics for particular patient prescriptions. These practitioners are clearly acting "off-label," as the FDA has not certified their designs for safety. Other names of Ortho-K Lens include Night lenses, Ortho-K, OK, Overnight Vision Correction, Corneal Refractive Therapy (CRT), Accelerated Orthokeratology, Cornea Corrective Contacts, Eccentricity Zero Molding, and Gentle Vision Shaping System (GVSS).

Ortho-K Lenses were developed in the late 1950s when eye experts found that nearsighted individuals who wore hard contact lenses saw a brief improvement in their unassisted eyesight. This is because the curvature of the cornea affects how light is refracted and pictures are transmitted to the retina. Myopia (nearsightedness), hyperopia (farsightedness), and astigmatism can all be caused by an irregularly shaped cornea. However, the cornea is pliable and can temporarily adapt to a new shape. This breakthrough opened the way for corneal refractive treatment, often known as orthokeratology or Ortho-K.

 

Who will benefit the most from Ortho-K Lens?

Ortho-k is mostly used to treat nearsightedness (myopia). Eyeglasses, normal contact lenses, LASIK, or photorefractive keratectomy (PRK) can all be used to treat this visual impairment. Orthokeratology is a non-surgical procedure that allows some individuals to discard their glasses and avoid wearing contact lenses all the time. Orthokeratology is a fantastic alternative for any adult who has myopic prescriptions. It's also ideal for people with milder degrees of astigmatism. Furthermore, ortho-k is frequently utilized as a validated therapy option for farsightedness (hyperopia) and age-related lens hardening of the eyes (presbyopia).

Ortho-k is occasionally prescribed for children's eyesight correction. Some children's vision might continue to alter throughout maturity into their twenties. LASIK and other vision correction operations are not indicated until the patient's vision is steady. Ortho-K lenses can help practically everyone, but youngsters are especially ideal candidates. This is because LASIK surgery is not appropriate for these young people. Children who do not wish to wear glasses, on the other hand, typically obtain excellent outcomes with Ortho-K lenses. doctors now know that this therapy is one of the most effective ways of decreasing progressive myopia in children, and it is quickly becoming the gold standard for myopia control.

Other suitable candidates include people with a certain prescription range and those who require vision correction without the use of corrective glasses, such as pilots, police officers, or athletes. If you are physically active and cannot use glasses or contact lenses while participating in sports, ortho-k may be the best vision correction treatment option for you. Furthermore, Ortho-k is appealing to persons who work in dusty, unclean conditions where contact lens usage is challenging.

 

How Ortho-K Lens work?

The cornea is a transparent, dome-shaped window at the front of your eye that focuses light onto the retina and accounts for the majority of your eye's capacity to focus. Its tissue is very malleable. A 6 µm flattening of the corneal thickness (about 5% of the thickness of a human hair) results in 1 diopter of altered vision in myopia. As a result, a specifically designed lens may be utilized to gently massage the cornea, gradually reshaping it to the ideal form for focused vision. Once acclimatized, the corrective effect lasts up to 72 hours, which is long enough to be a realistic method of vision correction.

Your ophthalmologist will use a corneal topographer to map and measure the surface of your cornea before designing a lens specifically for your eye. Reflecting light off the surface of the eye produces the cornea map. There is no discomfort and the machine does not touch your eye. Your ophthalmologist will be able to see the form and curvature of your cornea thanks to the corneal topography map.

Ortho-K contact lenses are a form of rigid gas-permeable contact lens. It is so precisely made and structured that when the lens is worn while sleeping, the lens and tear layer of the eye work together to exert moderate pressure on the cornea, altering its shape. Each fully tailored lens has a pre-programmed therapeutic effect for each individual's prescription, eye shape, and visual demands. Ortho K lenses are quite pleasant to wear.

The lenses function by flattening the center of the cornea, altering the way light bends as it enters the eye. The majority of orthokeratology lenses are worn overnight to flatten the cornea before being removed throughout the day. These are rigid, gas-permeable lenses that are strong enough to sculpt the cornea while also allowing oxygen to pass through to keep your eye healthy.

When properly adjusted, an individual can experience clear vision after removing the lenses in the morning, with the benefit continuing throughout the day. The lenses should be used every night throughout regular sleep for optimum results. After only one night of Ortho-K usage, all the Ortho-K patients experience an instant improvement in their eyesight, and some even reach 20/20 vision on day one. The majority of treatments require 1-2 weeks to properly stabilize.

When ortho-k lenses are removed, the cornea remains flattened for a short period of time, and eyesight is corrected without the use of glasses. If you stop wearing the lenses at night, your eyes will revert to their previous form, and the refractive defect will reappear. To retain the vision correction, you must wear the lenses on a daily basis.

It is a perfectly safe and reversible procedure. The effect fades off within 48-72 hours, and the cornea gradually returns to its original form. Ortho-K is a non-surgical, non-permanent alternative to laser correction surgery for many people. It also has the added benefit of considerably slowing down myopia growth in youngsters, something ordinary glasses and contact lenses simply cannot accomplish.

 

What are the effects suspected from using Ortho-K lens?

The cornea undergoes substantial adaptation between hours to days, with complete adaption commonly taking 2 - 3 weeks. Some people's vision may be impacted during this early period. Following adaptation, FDA testing revealed that more than 65 percent of patients acquired 20/20 vision and more than 90 percent achieved 20/40 vision or greater (the typical US requirement for driving without glasses).

Although the therapeutic impact is stable, it is not permanent. If left alone, the eye will gradually lose its corrected shape, requiring roughly 3 days to return to its previous vision. The Ortho-K lenses must consequently be used on a daily basis in order to keep and maintain the corrected corneal shape. They are normally worn for a portion of the day (often only when sleeping at night); some users may only need to use them one night every two or three nights.

Orthokeratology typically takes a couple of weeks or more to accomplish adequate vision correction, although some patients enjoy significant vision improvement in just a few days.

Patients may require a succession of temporary ortho-k lenses before attaining the required prescription. To achieve the optimum vision correction, you may need to wear up to three pairs of this precise corneal reshaping technology, one after the other. When your corneas have reached the ultimate ideal curvature, you will begin utilizing retainer ortho-k lenses. You may wear them if your eye doctor advises you to.

Ortho-k vision benefits are reversible, but they can be sustained if used as instructed. Clinical trials on ortho-k lenses approved by the Food and Drug Administration yielded a vision of 20/40 or better. One of the most successful optical therapies for myopia correction is orthokeratology. Several variables, as previously stated, make a person a perfect candidate for orthokeratology.

Ortho-K lenses can correct mild to moderate short-sightedness, long-sightedness, and even astigmatism, allowing for acceptable functional vision during the day without the use of glasses or daytime contact lenses. Ortho-K lenses are frequently fitted by ophthalmologists for prescriptions up to -7.00 diopters, and sometimes higher prescriptions are feasible depending on patient appropriateness. Doctors have fitted prescriptions as high as -10.00 diopters of myopia.

Ortho-K allows people to enjoy good vision without the need for glasses or daytime contacts. Some patients are long-term soft contact lens wearers looking for an alternative since normal contacts cause their eyes to become overly dry. Some have considered laser surgery but prefer a non-invasive option, or their prescription has not yet stabilized sufficiently for permanent surgical correction.

 

For children and teenagers, Ortho-K lenses have two benefits:

• Restoring their eyesight so that they no longer need glasses for school, sports, and other activities.
• Slowing the deterioration of their short-sightedness (myopia) and preventing their prescription from becoming stronger by minimizing abnormal eye elongation. That implies improved eyesight and eye health.

Ortho-K is the most successful optical therapy for myopia correction at the moment and is often recognized as the "gold standard." Many clinical studies published over time have shown Ortho-K to be helpful in lowering the rate of myopia progression by roughly 50% in eligible children, and some children have had even greater outcomes.

 

How long does the effect of the Orthokeratology lens last?

Although patients should wear their contact lenses every night for optimum outcomes, the effects typically last longer than one day. In fact, after wearing Ortho-K lenses for one night, it is normal for patients to have corrected vision for up to two full days. The lenses may be worn throughout the day, but they are more pleasant at night since they reshape the cornea. It's usually more vital to wear the lenses every night at first when the reshaping process is taking place. You may be able to wear them more frequently as your therapy proceeds.

 

Does Ortho-K Lens hurt?

Some people experience discomfort when wearing gas permeable contact lenses during the day. However, while ortho-k lenses are worn while sleeping, comfort and lens awareness are often not an issue.

It may appear that corneal reshaping is painful, but it is not. This is due to the fact that the reshaping is not the consequence of squeezing or "squishing." Instead, it is caused by hydraulic forces. The lens creates a vault of fluid over the eye, causing some portions of the cornea to absorb more fluid than others, altering the shape of the cornea and temporarily addressing curvature abnormalities.

 

What are the Complications associated with Ortho-K Lens use?

Ortho-k is linked to a higher risk of infection (microbial/bacterial keratitis). This danger is especially problematic for children and teenagers, who may be less able to maintain proper hand and contact lens cleaning than adults.

Every year, about a million Americans seek medical attention for eye infections. Contact lens usage is the leading cause of infection. Eye infections can have devastating effects, including permanent vision loss. As a result, ortho-k may be more problematic than glasses for correcting the same issues. That is one of the reasons why, if you are seeking ortho-k, you should check with an ophthalmologist. According to a Chinese study, the use of Paragon CRT lenses in children might cause complications like bacterial corneal ulcers.

The absolute incidence of bacterial corneal ulcers in Ortho-K lens patients is unclear. Before prescribing Ortho-K lenses to children, extreme caution should be taken, and informed consent should include the possibility of sight-threatening corneal ulcers. Although sight-threatening corneal ulcers are uncommon, informed permission should be acquired for all new contact lens wearers, regardless of whether they are used overnight or not.

A Canadian study described two cases in which Acanthamoeba infections caused temporary or permanent blindness following ortho-k therapy, presumably due to cleaning the lenses in tap water. There is no time restriction for wearing orthokeratology lenses. Regular check-ups with your ophthalmologist are required. However, if your eyes remain healthy and comfortable, ortho-k may be worn for many years.

Because Ortho-K lenses are normally used for significantly shorter durations (6-8 hours rather than daytime or 24/7) and when asleep rather than active, the risks are equivalent to or safer than regular contact lenses. They also compare favorably to surgical correction because there is no surgery involved, corrections to the eye's shape can be handled over time (surgery corrects vision at a single point in time, but post-operative ongoing changes to eyesight will occur throughout the patient's lifetime), and it is generally safe for younger patients.

Furthermore, from a safety standpoint, Ortho-K is not "new"; contact lens safety is widely thought to be well established. However, like with other contact lenses, it is critical to maintain excellent cleaning and hygiene practices. Rigid lenses are not as pleasant as soft lenses, however Ortho-K claims to eliminate the sensation of the eyelids sliding across the lens borders while blinking during awake hours. With Ortho-K lenses are worn, the eyes are closed during sleep, but the same concerns that occur when wearing contact lenses during sleep (rapid eye movements and decreased tear production) persist. 

 

Contraindications may include: 

• Inflammations or infections of the cornea or anterior portion of the eye.
• A disease, injury, or abnormality that affects the cornea, conjunctiva, or eyelid, or has an influence on contact lens wear.
• Extremely dry eyes or poor eye moisture.
• Corneal hypoesthesia (low sensitivity)
• Allergies to contact lens solutions and other eye-related allergies.

Some users may have visual impairments like ghosting, double vision, contrast problems, and/or starbursting during the first month of lens usage, while the treatment zone on the surface of the cornea is still forming. These problems are usually cured by the end of the first month of wearing the lenses. If these problems remain beyond the initial time, the culprit might be a lack of centration of the lens on the eye and/or an excessively big pupil size (in light or dark). Redesign, material improvements, improved eye moisture retention (night eye masks, duct blockage, etc.) or other measures may help.

Complications are more likely to arise when the patient fails to follow proper hygiene requirements when handling or cleaning the lenses. One typical concern is the use of tap water to rinse (although some systems allow for or recommend the use of "clean" tap water) or storage, which may produce undesirable mineral buildup on the contact as well as other problems.

Complications may also occur as a result of relative corneal hypoxia (lack of oxygen) caused by extended or nighttime contact lens usage in lenses composed of the incorrect material. The use of high or hyper oxygen-permeable materials certified by the US Food and Drug Administration, on the other hand, greatly lowers hypoxia. The same safety advice that applies to most types of contact lenses also applies to ortho-k night-time lenses.

 

Can I have LASIK surgery after using Ortho-K Lens?

Yes, LASIK surgery may be performed after orthokeratology. However, because ortho-k lenses alter your cornea, you must remove them for a period of time (often several months) to allow your eyes to recover to their former shape and settle. Tell your LASIK surgeon that you've been wearing ortho-k lenses so they can advise you on how long you should wait before undergoing the operation.

 

How much do Ortho-K Lenses Cost?

In most circumstances, orthokeratology would be a therapy of choice. There are frequently simpler, less expensive, and more well-known treatments for correcting refractive problems, including as eyeglasses. However, in rare circumstances, insurance may recommend and pay for ortho-k lenses.

The cost of ortho-k, including follow-up treatment for lens fitting, can vary greatly depending on the kind and degree of refractive defect. Ortho-k costs typically vary between $1,000 and $4,000. Annual expenditures for lens replacement, lens care products, and follow-up exams can range between $300 and $500.

 

Conclusion 

Orthokeratology, often known as ortho-k, is the temporary reshaping of the cornea with specially designed and fitted contact lenses in order to improve vision. Ortho-K lenses are gas-permeable lenses used to reshape the cornea. When the patient removes the lenses in the morning, they will have good vision for the rest of the day without the need for glasses or daytime contact lenses.

Ortho-K lenses can be used to address a variety of vision issues, including astigmatism, myopia (nearsightedness), and hyperopia (farsightedness). Nearsightedness is the most common condition for which ortho-k is used. This visual impairment can be treated with glasses, regular contact lenses, or LASIK surgery. Orthokeratology is a non-surgical method that allows some people to stop wearing glasses and instead wear contact lenses all the time.

Although the therapeutic effect is steady, it is not long-lasting. If not used properly the eye will start losing its corrected shape, taking around 3 days to return to normal vision. As a result, the Ortho-K lenses must be worn on a daily basis in order to retain the correct