What is the difference between prolonged lens wearing and continuous lens wear?

Modern medicine has made great breakthroughs in the field of ophthalmology. Today, people with poor vision successfully use contact lenses, which can be worn for several days without removing them. Modern optical devices are completely safe for human health. Depending on the model, they are characterized by prolonged and continuous wearing mode.

Advantages and disadvantages of optical products

Thanks to modern technologies for producing contact lenses, a person with poor vision can lead a normal life (swimming, traveling, having a prestigious position, enjoying all the subtleties and colors of the world around them). Thanks to the silicone hydrogel material used to make contact lenses, oxygen easily penetrates through it to the cornea of ​​the eye. This significantly reduces the risk of developing negative symptoms:

• there is no unpleasant burning of the eyes from the products;
• there is no feeling of dryness of the visual organs;
• there is an opportunity to work fully in equal conditions with well-visioned employees.

The only disadvantage of using optical products for vision correction is proper care for them. This problem is solved by using optical products for one-day use. They do not require periodic cleaning and disinfection; they are simply replaced with new ones after a day of wearing.

When asking the question of what to do for people with poor vision who do not have the opportunity to change contact lenses daily, one can answer that in pharmacies it has long been possible to purchase products with a prolonged and continuous mode of use.

Tips for caring for lenses

Proper contact lens care prevents serious eye diseases, some of which can lead to blindness. Such care involves following the following recommendations:

• Remove contact lenses before any contact with water: when taking a bath or shower, when swimming in a pool or swimming in a pond.
• Be sure to wash your hands before removing and putting on your lenses. Hands should be washed with soap and dried with a towel.
• Clean contact lenses as recommended by your eye doctor or lens manufacturer.
• Disinfect your lenses. Regular saline and moisturizing drops are not suitable for disinfection as they do not kill bacteria. Choose special antibacterial agents for disinfection.
• To clean and disinfect lenses, use only a fresh portion of the product.
• Store lenses in a clean, sanitized container.
• Do not use contact lenses for longer than the period specified in the instructions.
• Do not lend your contact lenses or contact lens case to others.
• If the lenses cause noticeable discomfort or even pain, remove them and consult a doctor immediately.
• Visit your ophthalmologist regularly. This will allow you to determine how suitable your lenses are for you, as well as to notice early signs of infection or eye disease.

Risk of long-term wearing

Almost all ophthalmologists believe that long-term wearing of lenses is extremely undesirable for eye health. They should be worn only when specifically necessary or at the strong request of the patient. Research over the years has shown that wearing this type of wear can cause microbial keratitis.

Continuous wear of lenses can cause this disease, which can lead to the most dangerous complications for the eye. For 20 years, ophthalmologists have studied this problem and identified the following trend: if you wear lenses only during the day and take them off at night, this disease does not develop. With prolonged wear, the risk of its occurrence is quite high.

Every person should have their vision checked at least once a year. An ophthalmologist will help you choose the right treatment for eye diseases and prescribe the necessary drops or lenses that will help the patient see better. Sometimes complex therapy can significantly improve people's vision. If your profession requires you to use products with a long wearing life, then follow the rules that are prescribed in each instruction for these products.

The most popular manufacturers of these products are Cuba Vision. They produce high-quality products, which are appreciated not only by experts, but also by ordinary users. Nowadays, lenses are so improved that people can safely use them in everyday life without fear for their health. Everyone should buy products only from companies that have an excellent reputation in the modern medical market.

Modern brands

The most popular are long-wear contact lenses from manufacturers such as Bausch + Lomb, CIBA Vision, Johnson & Johnson and Cooper Vision.

Bausch+Lomb

Bausch + Lomb produces Pure Vision continuous wear silicone hydrogel lenses. They provide high clarity of vision even in poor lighting and in the evening. Thanks to special manufacturing technology, the lenses are comfortable and safe to use. The oxygen transmittance of Pure Vision lenses is one hundred and thirty units.

CIBA Vision

One of CIBA Vision's products is Air Optix Night & Day contact lenses. They can be worn for a whole month, while providing complete comfort to the eyes, since the lenses are not felt on the eyes. Air Optix Night & Day lenses are made from lotrafilcon B, which provides good hydration. And their smooth surface does not accumulate protein and fat deposits.

Read more about daily colored lenses with diopters in the article.

Acuvue Oasys by Johnson–Johnson

Acuvue Oasys lenses from Johnson & Johnson can be used for up to seven days of continuous wear. The oxygen transmittance coefficient of these lenses is one hundred and forty-seven units, which provides one hundred percent comfort.

Cooper Vision

Contact optics manufacturer Cooper Vision offers Biofinity continuous wear lenses. Their manufacturing technology allows you to wear lenses without removing them for up to fourteen days in a row. Biofinity lenses have a high oxygen transmittance (one hundred and sixty units) and moisture content (forty-eight percent).

What are two-week lenses

Biweekly lenses are soft, routine replacement lenses that can be worn for two weeks. This means that they are put on in the morning and taken off in the evening.

It is important to know how to choose daily contact lenses. However, there are also two-week long-acting lenses that can be left in place at night for up to 6 days.

This type of contact lenses is especially convenient for those who use them every day. Firstly, this option is much less expensive than buying one-day lenses, and secondly, after one-day lenses they have the shortest service life, during which time they do not lose their characteristics and do not have time to accumulate microbes harmful to the eyes.

Two-week lenses are the most comfortable for the eyes:

• They are made of soft, oxygen-permeable material;
• They have a smooth but non-slip surface, which makes them easy to put on and take off;
• They do not have time to accumulate protein that is harmful to vision.

Tips for choosing lenses

Each person is individual, and each of us has special vision parameters. Therefore, the ophthalmologist writes a prescription for contact lenses taking into account visual acuity, optical power and radius of curvature, and so on.

In order to choose the right glasses, you need to check your visual acuity, see how to do this at this link.

Let's look at the most popular brands of continuous wear lenses and their features that will help you make your choice:

Bausch&Lomb. The manufacturer states that the lenses are intended for continuous use for one month. However, in reality everything is different: they must be removed at night after eight hours of wearing, otherwise you can get corneal edema. The problem is that Bausch&Lomb lenses are made of hydrogel. This material does not have very good oxygen permeability. According to the manufacturer, Optima FW lenses are very convenient and comfortable. Customer reviews of lenses for continuous wear for up to three months vary greatly. Some people think the lenses are good, while others say they will never wear them again. PureVision 2 HD. These lenses have a one-month replacement period and are made of silicone hydrogel. This material allows oxygen to pass through well, so the eyes “breathe” throughout the entire wearing period. PureVision 2 HD long-wear lenses are also suitable for dry eyes.

Bausch&Lomb

• Ciba Vision. Air Optix Aqua lenses have special UV protection. Therefore, they prevent the development of lens opacities, corneal dystrophy and many other problems. Lenses from the manufacturer Ciba Vision are well moisturized and have a high degree of oxygen permeability.
• CooperVision. This manufacturer produces two types of lenses for long-term wear: Biomedics 55 and Biofinity. Biomedics 55 continuous monthly wear lenses are well-hydrated and have up to ninety-eight percent UV protection. And Biofinity lenses are very comfortable and are not felt on the eyes.
• Johnson&Johnson. Lenses from this manufacturer are considered the most comfortable. The material used is silicone hydrogel. It provides good oxygen permeability. One of Johnson&Johnson's product options is ACUVUE OASYS monthly lenses for two-week continuous wear. They have UV protection and are suitable even for dry eyes.

Johnson&Johnson

Tips for choosing

You need to choose your daily wear contact lenses step by step.

1. Consultation with an ophthalmologist who will conduct a vision diagnosis on a computer.
2. The doctor provides information about the types of contact lenses and their use.
3. Selection of the optimal type of lenses.

The first stage is that the specialist conducts a full diagnosis. He checks visual acuity, corneal sensitivity, eye microflora, and so on.

At the second stage, the ophthalmologist will talk about the types of lenses and their manufacturers. Most often, the doctor suggests choosing imported soft contact lenses. Plus, he can recommend moisturizing eye drops.

The third stage is choosing a wearing mode. The most optimal mode is considered to be daily wearing of lenses. The lenses can be worn for up to twelve hours a day, and removed at night and treated with a solution.

The correct selection of contact lenses and methods of wearing them are described in the article “How to properly remove lenses from your eyes”

If you don’t know which lenses are better for daily or monthly wear, read here.

How to choose contact lenses for your eyes:

Technique of use

As a rule, you can try putting on and removing contact lenses for the first time in your eye doctor's office. The doctor can tell the patient about 2 existing application methods. You can put on the lens using both hands or one of them. The future user independently determines which method will be more convenient for him to perform all the necessary manipulations with it.

Putting on with both hands

Place the lens on the pad of your index finger. Using the middle finger of one hand, pull down the lower eyelid. Using the middle finger of your other hand, pull your upper eyelid upward. After this, apply the lens to the mucous membrane of the eye and, without letting go of the eyelids, move your gaze: the lens will be in the desired position. Then you can release both eyelids.

One-handed putting on

Place the lens on the pad of your index finger. Using the middle finger of one hand, pull down your lower eyelid while looking straight ahead. You can hold the upper eyelid with your other hand to prevent blinking. Turn your gaze upward and, without looking at the lens, apply it to the mucous membrane of the eye. After this, slowly lower your gaze down and release your lower eyelid. Then you can close your eyes and the lens itself will move into the desired position.

Removal

Pull your lower eyelid with your middle finger while looking upward. At the same moment, slide the lens down using your index finger. Using the pads of your index finger and thumb, pick up the lens using a pinching motion and place it in a container with the solution for subsequent storage and disinfection. Do the same with the second lens.

What is better to use - plus contact lenses or glasses for vision?

When deciding whether optical lenses or contact lenses are better, the patient’s wishes alone are not enough. The following details are important:

1. Age. It is not recommended for patients under 12 years of age to use the contact method of correction. Elderly people have difficulty fixing products. Therefore, doctors most often recommend glasses to such patients.
2. Type of professional activity. If a person works in a chemical plant and a dusty factory, then glasses are better suited. Doctors will help you choose glasses for your vision, and also advise patients who work in the medical and construction fields to use lenses. The contact method is also indicated for professional athletes.
3. Health status. If you have problems with coordination of movement, fine motor skills or mental disorders, then wearing contact lenses is prohibited.
4. Driving. For people who spend a long time driving, ophthalmologists recommend using soft lenses. Thanks to them, high clarity of vision at night is achieved.

What are daily wear contact lenses?

The mode of wearing contact lenses implies the period of time during which you are allowed to wear the lenses without removing them. In particular, daytime wear is the use of lenses only during the day. These lenses should be removed at night.

It is recommended to wear daily lenses no more than twelve hours a day. After removal, they need to be placed in a container with a disinfectant solution so that by the morning the optics are fresh and clean.

• Day lenses can be hydrogel or silicone hydrogel.
• Hydrogel lenses are very comfortable to wear, they are thin and soft. Such lenses moisturize the eyes well, but have a low percentage of oxygen permeability.
• Silicone hydrogel lenses allow oxygen to pass through well, they are more elastic than hydrogel lenses, so they hold their shape well.

If you choose silicone hydrogel lenses, you should remember that it is important to follow the wearing regimen:

• It is necessary to cleanse every evening.
• After the wearing period has expired, you should throw away the old pair and put on a new one.

Daytime contact lenses vary in terms of wearing time:

• Traditional lenses can be worn from six months to nine months. They are the most affordable, but they will require not only a regular solution, but also an enzyme solution, since these lenses accumulate protein and lipid deposits.
• Quarterly lenses have a wear period of three months.
• Planned replacement lenses can be worn for a month. They are the most popular lenses. You don't need to use an enzyme solution for them.
• Frequently scheduled replacement lenses have a service life of up to two weeks.
• Daily lenses are put on in the morning and removed and discarded at night. They are the safest for the eyes.

Rigid gas permeable lenses

Another type of lens approved for long-term continuous wear is rigid gas permeable lenses. Such lenses allow oxygen to pass through well, although they are inferior to soft lenses in terms of wearing comfort. Gas-permeable hard contact lenses can also be worn for 30 days and not removed at night. The only limitation is individual intolerance due to the rigidity of the material, which causes some discomfort when wearing and a constant feeling of the presence of a foreign body in the eye.

Risks associated with continuous wearing

Ophthalmologists say that using lenses for a long time throughout the entire month without removing them is extremely undesirable. Therefore, they recommend such contact optics only to those who really need it.

This is a very serious complication that leads to a significant decrease in vision and scarring of eye tissue. In sixty percent of cases, microbial keratitis occurs due to failure to comply with the deadlines for replacing contact lenses and improper storage.

Flexible wearing mode as an alternative

Despite the fact that long-wear contact lenses are made from modern and high-quality materials, this mode increases the risk of developing various complications. Many experts agree that the most optimal mode for using such contact lenses is a flexible mode.

What is “long” wearing mode?

Long-wear lenses require use for thirty days. They can be worn during this time without removing them at all, or they can be worn in a combination or flexible mode, which involves occasionally removing the lenses at night. In addition, lenses designed for continuous wear can be used in extended mode, that is, the lenses do not have to be removed at night for the entire duration of use.

Thanks to this “long” wearing regime, the lenses are perfect for people who lead an active lifestyle and play sports, work at night, or for those who find it difficult to adhere to the wearing regime.

Find out if glasses with holes help restore your vision here.

Experts still recommend at least sometimes removing continuous wear contact lenses at night. This will allow your eyes to rest and disinfect the lenses to minimize the risk of developing any problems or complications.

Pros of long-term wearing of contact lenses:

• There is no need for daily maintenance or use of disinfectants.
• The lenses are absolutely safe, they allow the eyes to breathe, so the quality of vision does not decrease over time.
• Possibility of using lenses in combined mode. But in this case, you will need a solution for hard lenses, their storage and cleaning.
• Saving time, the opportunity to lead an active lifestyle.
• The correction range starts from +6.0 and ends at -12.0 diopters, which allows the use of such lenses for myopia, farsightedness and presbyopia.

By wearing period

Disposable

Disposable or daily lenses can be worn up to fourteen hours a day. After which the used pair is thrown away and a new one is used the next day.

Advantages:

1. There is no risk of developing allergies.
2. Safety for eye health.
3. Comfort and clarity of vision.
4. No need to buy solutions or containers.
5. Ease of use.

The most common brand of manufacturer
Disposable lenses are suitable for vision correction and can be used as a replacement for conventional lenses. They are also used after instilling eye drops that dilate the pupils.

Reusable

Reusable lenses are lenses that are used throughout the day and removed before bed. The replacement period for such lenses is once every two weeks.

At night, reusable lenses should be stored in a container with a special solution.

Traditional (from a week to a year)

• The period of use is from six to nine months.
• The material used to make them is hydrogel.
• It is necessary to thoroughly clean the lenses with a disinfectant solution.

Modern manufacturers

• Baush & Lomb. This is one of the largest modern manufacturers of lenses and care products. The most famous and popular lenses from this manufacturer are PureVision silicone hydrogel lenses and Optima and SofLens hydrogel lenses.
• CIBA Vision. The manufacturer CIBA Vision is recognized as one of the leaders in the production of contact optics and additional care and disinfection products. Their lenses are very varied and are made from hydrogel and silicone hydrogel.
• CooperVision. This manufacturer ranks second in lens production. CooperVision is a world leader in toric lenses. Their range is very diverse; many types of lenses can be purchased in Russia.
• Johnson & Johnson Vision Care. This manufacturer is a leader in the production of soft contact lenses. Their most famous product is Acuvue lenses. This family of lenses includes hydrogel and silicone hydrogel lenses.

Educational program on contact lenses

The number of bespectacled people today can be counted on one hand. Every fifth beauty has eyes whose brightness is far superior to all shades existing in nature. In the clubs, glamorous fifas of both sexes with pupils in the shape of dollar signs are lit up. And all this thanks to contact lenses. Reliable, convenient, beautiful.

It would seem that getting contact lenses is as easy as shelling pears; these are not glasses with which you have to spend hours choosing the frame. However, when it comes to a visit to the optician, we get lost... Our eyes widen from the variety, and the consultant confuses us with clever terms, names of companies and materials.

What are they wearing now?

Now there are more than enough contact lens manufacturers on the Russian market. The most famous: Johnson & Johnson Vision Care; CIBA Vision, Bausch&Lomb, Maxima. Almost all of them offer a full line - from daily lenses to extended wear lenses.

By the way, it is one-day (disposable) lenses and those that can be worn without taking them off that are the priority areas of scientific research of leading scientists who attract consumers with their convenience - “put on, take off, throw away”, “long lasting” - because “put on and forget”.

Daily lenses

The main disadvantage of "daily" is the lack of moisture and low oxygen permeability of the material. Therefore, manufacturers tirelessly invent humidifiers that are “built-in” into the lens and are released throughout the day, or, conversely, add components that help retain existing moisture. Such lenses are made from biocompatible materials, which ensures their comfort and safety.

However, recently the Russian market has not been spoiled with new “daily products” - the most progressive ones, released several years ago, are “Focus Dailies All Day Comfort”, “1-Day Acuvue Moist” and “Maxima 1-Day”.

“Daily lenses” are the most expensive lenses on the market. That's why doctors often don't even suggest patients try them. But in vain. In the end, each of us is able to plan our own budget without the help of doctors. "Daily" is perfect for people suffering from allergies; those who usually wear glasses and use lenses only occasionally; as well as children, travelers and lazy people. According to doctors, such lenses are the safest.

Extended wear lenses

Previously, lenses were made from a material called hydrogel - they had to be removed at night and placed in a disinfectant solution, and put on again in the morning. All attempts to sleep in such lenses ended in failure - patients' eyes became red and swollen, and the risk of developing eye diseases increased. All this was a consequence of the low oxygen permeability of the hydrogel. It is, of course, higher than that of “daily bags” (in which you absolutely cannot sleep), but it is still not sufficient for eye comfort for a long time.

Modern long-lasting lenses are made from a more advanced material - silicone hydrogel. Such lenses have the highest oxygen permeability, which allows for increased comfort during continuous wear - the eye “breathes” in such a lens.

The latest achievement of the developers of silicone hydrogel contact lenses is “Acuvue Oasys with Hydraclear Plus”. A so-called moisturizing agent is added to their composition. It prevents the eyes from drying out and, accordingly, increases the comfort of the lenses.

“Moisturizing and breathable” lenses can be worn without removing them for seven days, after which they go in the trash. None of the previously released silicone hydrogel lenses contain moisturizing agents, so the appearance of a new product will most likely force other manufacturers to also come up with something similar.

When there is no agreement among comrades

Unfortunately, despite all the new products and inventions, there is still no complete unanimity between contact lens manufacturers and ophthalmologists.

Judge for yourself. Advertising information from some manufacturers: silicone hydrogel lenses can be worn without removal for 30 days. Yes, certifying organizations give permission for such long-term wearing, but doctors are categorically against it! The latest models – the already mentioned “Acuvue Oasys with Hydraclear Plus” and the comparable “O2optix”, which appeared a little earlier, are intended for continuous wear only for 6-7 days. Do you feel the difference?

Make no mistake - lenses of the previous generation, by definition, cannot provide the patient with more convenience and safety than newer ones!

Doctors warn that continuous wearing of lenses for more than seven days is fraught with serious complications (including corneal ulcers). If you’re too lazy to keep track of deadlines, tinker with solutions and containers, don’t bring yourself to the state of Gogol’s Viy (when you can’t open your eyes on your own some morning that isn’t beautiful) - buy “daily items”.

The choice of professionals

Everyone benefited from the introduction of contact lenses. And bespectacled people, teased since childhood by unkind classmates, and people with very poor eyesight, whose glasses often look ugly because of the thickness of the glasses, and those who stare at the monitor screen for hours, like you and me.

It is believed that sitting at a computer wearing contact lenses is much more comfortable than wearing glasses. They do not glare, and the field of view is larger.

On the other hand, computer users who wear contact lenses often complain of dry eyes. This is due to the fact that a person, looking at a monitor screen, blinks approximately 3-4 times less often than usual. In addition, office air conditioning and dust microparticles dry out the eyes. Plus, the evaporation of moisture from the surface of the lenses is higher than from the surface of the eye. Here you have “dry eye syndrome” with a feeling of sand, specks, and burning in the eyes. Therefore, experts recommend wearing lenses that retain moisture well when working at a computer, that is, the very latest developments.

Perhaps most of all, athletes (and people leading an active lifestyle) have benefited from the advent of comfortable contact lenses. Imagine a football player or biathlete wearing glasses... Funny! But contact lenses suit them very well. Even swimmers can wear contact lenses. Moreover, the lenses protect your eyes from chlorinated swimming pool water. The only risk that aquatic lens wearers risk is surfacing without a lens. In water, the lens can simply “float” out of the eye, and it is unlikely to be found in the bluish abyss of the pool.

Contact lenses that protect the eyes from ultraviolet radiation are not uncommon today. But so far, even manufacturers cannot decide whether it makes sense to add a UV filter to the lens material or not. For example, it has not yet introduced a UV absorber into any of its manufactured contact lenses. The company believes that lenses with UV absorbers do not provide 100% eye protection from ultraviolet radiation.

Anti-astigmatism lenses

Quite recently, a unique new product appeared on the Russian market - soft contact toric lenses designed to correct astigmatism. This is practically a revolution in the world of contact lenses, since previously one could only dream of the possibility of contact correction of astigmatism.

Today, in many optical shops there are posters on which a symbolic sun is drawn from dashes, and below the signature: close your right and left eyes in turn. If any of the rays of the “sun” change color, you urgently need to see a doctor for a diagnosis and news.

To be fair, I’ll say that my friend and I recently squinted at such a poster. As a result, both of them had to go for the new product - she, with long-diagnosed astigmatism, and I, whose ophthalmologist had just confirmed its complete absence. So trust doctors, not advertising posters!

Kinds

Contact lenses, depending on various parameters, are divided into the following types:

1. Depending on the material: hydrogel and hydrogel-silicone, polymer lenses.
2. Depending on the frequency of replacement: one-day, one-two weeks, 3 months, 6 months, annual.
3. Depending on the mode and time of wear: daytime, prolonged, flexible, continuous.
4. Depending on the level of transparency: transparent, colored.
5. Depending on the type of design: multifocal and spherical.

Ophthalmologists do not divide lenses into small groups and distinguish two main types based on the type of material:

• Soft lenses;
• Hard lenses.

More than 90% of ophthalmologists' patients wear soft lenses, because they are an excellent means of vision correction and have virtually no contraindications for use. This type of lenses is made on a hydrogel and silicone hydrogel base, which is why they must be stored in a special container with a solution.

As for hard lenses, they have a number of advantages over soft ones:

• Retains its shape for a long time;
• They wear for a long time;
• Significantly increase visual acuity;
• Provide a tight fit to the cornea of ​​the eye.

They are ideal for vision correction in the presence of diseases such as astigmatism, orthokeratology, keratoconus. These lenses are made from polymer materials that provide a high degree of oxygen penetration to the cornea.

Proper lens storage

Specifics of wearing contact lenses

New generation lenses are very helpful for people with poor vision, because they allow them to work, play sports, travel, enjoying the brightness and contrast of images and color rendition. With the advent of contact optics made of silicone hydrogel material, which combines all the advantages of silicone, which allows oxygen to easily pass to the cornea and hydrogel, the number of users experiencing unpleasant symptoms has decreased. Now those who have chosen contact lenses as the main method of vision correction do not feel dry or burning eyes, even if they work intensively with digital technology and are exposed to visual stress on a daily basis.

The only disadvantage of contact lenses, which are significantly superior to glasses in all respects, is the care of the optics. But this problem was successfully solved by one-day optical products that do not need to be cleaned and disinfected. But what about those who do not have the opportunity to remove their lenses in a timely manner in the evening, who are on a trip, or who work at night? For such consumers, manufacturers produce lenses with prolonged and continuous wear.

What are the specifics of the wearing mode? Why can some lenses be worn for a long time, while others cannot? Let's look at each mode:

• daytime wear - such models are designed for use during the day, for 10-12 hours, during this period they retain the moisture content characteristics declared by the manufacturer, and then the level of moisture may decrease, which causes significant discomfort to the user;
• flexible mode - daytime sleep in lenses is possible, night sleep is undesirable, but allowed (1-2 nights in a row);
• prolonged mode - you can wear optical products without removing them for one week;
• continuous wearing - with permission from an ophthalmologist, such models can be worn for 30 days, without interruption.

The best option for daytime wear are one-day models that do not require disinfection or cleaning of deposits. Contact optics, recommended for continuous or prolonged wear, have many advantages, since they remove many restrictions and allow you to forget about poor vision for a while.

Features of the selection of lenses with diopters

An experienced doctor should help you choose lenses. He will be able to give recommendations regarding the type and mode of such devices. If you purchase it yourself, it is a waste of money, and sometimes the cause of the development of adverse events. This article will tell you about women's glasses.

When choosing products, the following diagnostic procedures are of particular importance:

• visometry – determination of visual acuity;
• refractometry - determination of the refraction of the eye;
• ophthalmoscopy – examination of the fundus of the eye;
• accommodation - study of the reserve of accommodation;
• diagnostics of lateral vision and the ability to simultaneously see a picture clearly with both eyes.

For age-related hypermetropia

It is also worth knowing that multifocal lenses are one of the most effective means of correction for people suffering from age-related farsightedness. There are basic criteria for the correct selection of optical products:

1. Optical power. It is responsible for the degree of farsightedness in a particular person.
2. Radius of curvature. Each person has a different structure of the eyeballs, but choose a product with a standard radius of 8.6 mm.
3. Water concentration. The higher this indicator, the more practical the lenses will be. If you choose more rigid devices, they guarantee picture clarity
4. Oxygen permeability. The risk of developing negative phenomena depends on this indicator.
5. Tensile strength. The duration of wear depends on this parameter.

Reasons for wearing lenses

Lenses are the preferred optics option, recommended by the vast majority of doctors to their patients. Indications for wearing such products are:

• Farsightedness and myopia, including high degrees;
• Astigmatism (in this case, special toric lenses are used);
• Intolerance to spectacle vision correction;
• A significant difference between the diopters of the left and right eyes, for which the selection of glasses is extremely difficult;
• Vision correction for “lazy eye” syndrome.

Also, lenses are often worn if there are cosmetic problems, including color defects in the iris. Tinted samples of soft optics can also be used to give the eyes a more interesting shade (especially for light-colored irises). Less commonly, lenses are worn without any indication. However, in most cases, tinted models, as well as crazy lenses, are chosen for this.

It is these restrictions that you should first pay attention to when choosing certain product models.

Selecting lenses for long-term wear

Currently, the industry offers potential buyers a huge number of lenses with different wearing requirements. And in each category there are more and less acceptable samples for the vast majority of patients. They will be discussed below.

For continuous

This is the thinnest version of optics, which usually does not cause discomfort in use, provides normal air exchange to the cornea, and therefore generally reduces the risks associated with constantly wearing optics. Among the most popular and sought-after manufacturers of this type of product, experts note the following companies and their lines:

• Pure Vision (Bausch + Lomb), as well as Night & Day (CIBA Vision) - are indicated for continuous wear for 30 days.
• Biofinity by Cooper Visio - maximum use period - 2 weeks.
• Acuvue Oasys long-term wear contact lenses from Johnson & Johnson Vision Care are indicated for continuous wear for a week.
• PremiO from Menicon - the wearing period is also no more than 7 days.

All of the above optics allow you to correct the vast majority of visual impairments with maximum comfort for the patient and constitute the best alternative to glasses. And since the best material processing technologies were used during their development, they cause virtually no discomfort when worn.

Only after you have been examined by your doctor and are sure that similar models are indicated for you, can you order them.

Of course, for representatives of many professions and people leading an active lifestyle, such models are much more convenient. However, given the level of health risks associated with them, it is worth considering a safer option for yourself - lenses for daily wear.

For daytime and flexible

This type of optics is preferable for people with highly sensitive eyes, prone to allergic reactions, as well as those who cannot strictly comply with all optical hygiene regulations.

Among daily wear lenses, there are also favorites that have received high marks from ophthalmologists around the world. These include:

• OKVision Premium SiH-48;
• Maxima Optics (UK) Si Hy Plus monthly replacement samples;
• Avaira from Cooper Vision.

They are also suitable for daytime use.

Of course, both continuous wear samples and models for daytime use require careful selection and compliance with all requirements for their use. In this regard, each patient should receive a detailed consultation with the attending physician.

The saga of extended wear lenses

Over the past thirty years, the contact lens industry has experienced unprecedented growth, driven by scientific research and the development of new materials and production methods. In 1970, there were 2 million lens wearers worldwide, in 1986 there were 25 million, and today that number is 95 million. Despite this, people continue to search for the most optimal method of vision correction, and recently many have been thinking about refractive laser surgery or other alternative methods. At the same time, extended-wear contact lenses are considered as an alternative to laser surgery. These lenses have already appeared on our Russian market, but their introduction is accompanied by some information vacuum about their pros and cons. In this article we publish the results of recent research conducted in this area.

Long-wear contact lenses (which can be worn for up to a month) have long been considered a panacea for people seeking comfort, freedom and clear vision. Contact doctors use such lenses in order to achieve minimal changes in the natural environment of the cornea and minimize the risk of possible complications, in particular the occurrence of microbial keratitis. A study conducted by the Cornea and Contact Lens Research Unit (CCLRU) and the Center for Eye Research and Technology (CRCERT) found that patients are eager for a vision correction method to be found that can improve their visual perception once and for all; At the same time, 97 percent of respondents expressed a desire to wear lenses without removing them at least 6 days a week. Although quality of vision and comfort were noted to be the main factors in choosing contact lenses, 85 percent of respondents reported that they chose these lenses because they can be worn for long periods of time at night.

One study in the early 1980s found that nighttime corneal edema was avoided by using contact lenses with a Dk/t greater than 87. To date, similar lenses have been developed - two types of soft lenses and at least one type of hard gas permeable lenses. Silicone hydrogel soft contact lenses provide the same quality, comfort and surface characteristics as elective replacement lenses, but in addition they virtually eliminate hypoxia and associated changes in corneal structure and function.

Nocturnal corneal swelling with these new lenses is identical to nighttime corneal swelling when sleeping without lenses and much less than when sleeping with routine replacement lenses. A joint study conducted by CCLRU, CRCERT and the Center for Contact Lens Research (CCLR) at the University of Waterloo (Canada) showed that other signs of hypoxia - corneal striae, microcysts (a classic sign of epithelial hypoxia), endothelial polymegatism - in the case of the use of extended-release lenses. wear is extremely rare (if at all) compared to elective replacement lenses. Patients wearing these lenses experience unusually “white eyes” due to a decrease in hyperemia of the peripheral edge of the cornea and a complete elimination of limbal vascularization. Doctors and patients note the absence of redness of the eye.

Patients who successfully wore these lenses (follow-up period: 12 months) were very satisfied with them, with 93 percent rating them as excellent, according to the CCLRU and CRCERT study. The main reasons for these reviews were ease of use (eliminating the need for lens care - 88 percent), ability to see normally when waking up (7 percent) and overall comfort (5 percent). Ten percent noted that they completely forgot that they wore contact lenses. Before using extended wear lenses, two thirds of patients intended to go to a laser vision correction clinic for surgery.

After using these lenses, only 32 percent of them said they still considered the option of laser correction.

Despite these results, it should be noted that modern lenses are not the final stage in the development of extended-wear lenses. Studies conducted by CCLRU, CRCERT and CCLR have shown that although hypoxia-related adverse events are less common with extended wear lenses than with lenses with lower oxygen permeability (Dk), inflammatory processes such as ulcer of the peripheral part of the cornea, infiltrative keratitis, generalized papillary conjunctivitis, approximately the same as when wearing lenses with low Dk. The same can be said about complications arising from mechanical injuries (such as local papillary conjunctivitis). However, such complications do not pose a very serious danger to vision, and contact doctors can deal with them quite easily.

What principles and factors play a role in determining who is suitable for wearing such lenses, and what should be done when switching to 30-day wear lenses?

Patient selection

Currently, high Dk silicone hydrogel lenses are only available in spherical designs, so they are not suitable for people with 1 D or higher astigmatism. Previously, patients with high degrees of myopia or hypermetropia were not recommended to wear lenses with low Dk in extended mode due to the increased thickness of lenses of such refractions, which reduced the already low flow of oxygen to the cornea. New lenses with high Dk open up the possibility of extended wear for such people.

The physiological condition and stability of the cornea are the most important factors in deciding whether a person can wear contact lenses.

Prolonged wearing is not recommended for people with immune system disorders, severe allergies, or systematically taking medications. Potentially problematic patients are people who have a history of contact lens intolerance (eg, papillary conjunctivitis). With prolonged wear, such inflammatory processes may recur. Also, extended wear is not suitable for people who have had problems with daytime wear or have unsuccessfully tried to wear lenses without removing them for 6 nights in a row.

If a person who has never worn contact lenses wants to start immediately with extended-wear lenses, an adaptation period of at least one week should be provided, during which such lenses are worn during the day and the patient should not experience any discomfort. If no problems arise, you can switch to prolonged wear: the patient does not remove the lenses for one night and then undergoes an examination by a contact specialist. Then you can try leaving the lenses on for six nights in a row, after which the patient should be examined again, and if no undesirable effects are identified, only then can you move on to 30-day wear. Such a schedule allows the patient to get used to the lenses, and the contact specialist to determine the eye’s reaction to the silicone hydrogel material. Patients who have experience wearing contact lenses without complications can immediately switch to a prolonged wearing regimen.

Please remember that although silicone hydrogel lenses are designed for 30 days of continuous wear, flexible wearing is preferred. It is necessary to remove lenses if you feel any discomfort or discomfort. A lens removed for a short period of time should be cleaned before being put back on, and a lens removed overnight or for any other significant period of time should be disinfected. Do not use care products that have expired.

To summarize, it can be noted that the creation of silicone hydrogel contact lenses was a huge step forward in the fight against hypoxia, which gave patients the opportunity to wear lenses for a long time, up to 30 days. However, research shows that although the risk of complications associated with hypoxia is reduced, the likelihood of other complications remains the same and in some cases even increases. Therefore, an important role in the successful wearing of lenses in an extended mode is played by the correct selection of patients, getting used to the lenses under the supervision of a contact specialist, regular follow-up examinations, and compliance with the recommendations of the contact specialist.

Prepared by Vadim Davydov based on materials from the website www.siliconehydrogels.org.

Information provided by the online magazine about glasses and contact lenses www.Ochki.net

Selecting lenses for long-term wear

Silicone hydrogel lenses are today considered the safest among all types of extended-wear contact optics. They meet most of the requirements for continuous wear lenses.

Extended wearing mode

In the table we will look at examples of brands and manufacturers of lenses of this type offered on the market today.

Daytime and flexible wearing mode

All lenses presented above are suitable for both continuous, daytime and flexible wearing modes. The modern pace of life dictates to lens users their wearing regime, forcing them to keep their lenses on for 16-18 hours a day.

That is why manufacturers have developed contact optics with a daily and flexible wearing schedule. Such silicone hydrogel samples include the lenses shown in the following table:

Features of using lenses in different wearing modes

There are several models of contact lenses, which are characterized by the following technical characteristics:

• Daily use lenses are designed to be worn for 10 to 12 hours a day. During this time, they retain all the necessary technical properties declared by the manufacturer, for example, the required level of humidity for comfortable use;
• flexible level of use allows you to wear the optics for 1-2 days, but it is recommended to remove them before going to bed;
• Continuous use lenses can be worn continuously for a month, but it is recommended to consult an ophthalmologist first.

Lenses for daily use that do not require cleaning from dirt are considered optimal for daily wear. However, the prolonged action of other models is more comfortable, especially with a shift work schedule or frequent business trips.

Differences between lenses of different wearing techniques

Our product catalog contains a wide range of optical products from different manufacturers. Depending on the technical characteristics, we can list bestsellers with recommended wearing modes:

• Continuous wear lenses include: Air Optix Night & Day Aqua, Biofinity, Air Optix Aqua, Air Optix Plus HydraGlyde, Pure Vision 2 HD, Acuvue Oasys. Depending on the manufacturer's instructions, some of them can be worn continuously for a week to a month;
• disposable daily wear lenses include: 1 day Acuvue TruEye, Dailies Total 1, 1 Day Acuvue Moist, Dailies AquaComfort Plus. Wearing these products involves one-day use; technical properties are gradually lost after 10–12 hours of use.

Extended-release lenses can be used continuously for a week, while continuous-wear lenses can be used for up to 30 days in a row if there are no ophthalmic restrictions, provided they are removed at night.

How to use lenses

In the case of two-week daily wear lenses, remember that they must be removed at night. This way, your eyes will rest, and the lenses will be saturated with liquid and cleaned of dirt.

Lenses should only be put on with clean hands, and they should also be removed after washing your hands. If you are new to using lenses, a special lens remover will help you remove them. Not many people know how long they can wear lenses. It should be remembered that the time for using lenses begins to count down immediately after you open the blister with them. We must not forget about proper care of two-week lenses.

When putting on lenses, do not press them to the eye, just carefully place them directly on the cornea, center them and they will stick themselves and take the correct position

If you feel discomfort after putting them on, you need to pay attention to whether the lens is located in the center; if not, then it needs to be centered

It is worth remembering that lenses should be removed at night, unless they are extended-wear lenses, and should be kept in solution at all times.

Two-week lenses are worn for 14 days, after which they lose their performance properties, but do not cause irreparable damage to vision. Such lenses are the golden mean between daily and monthly lenses and have a number of advantages: they are much cheaper, and dangerous amounts of bacteria and infections do not accumulate on them.

Risks associated with continuous wearing

Why is this happening? The fact is that when wearing a lens constantly, the level of moisture in the eye noticeably decreases, which means that the mucous membrane actually becomes more susceptible to microbes. In this condition, a person is more easily infected with conjunctivitis pathogens and is more prone to allergic reactions.

In addition, it is when lenses are worn for a long time that protein residues accumulate on the eye.

Conjunctivitis is the most common of these ailments, but ophthalmologists consider it the lesser of the evils. Doctors call microbial keratitis a much more dangerous phenomenon. What kind of disease is this, and why the risks associated with it are so great, let’s try to figure it out.

Tinted lenses

Microbial keratitis

Keratitis is an inflammation of the cornea, which is accompanied by clouding, as well as pain and redness of the eye. The microbial form of this disease can be caused by amoebic infections. It is this type of disease that can lead to various complications, including the appearance of a cataract, as well as decreased vision and blindness.

It was practically excluded among those who preferred daily lenses from many companies, and was very often observed among people who preferred hydrogel lenses, especially those manufactured in the UK and the Netherlands. You can familiarize yourself with the pattern of occurrence of this disease among regular customers of certain manufacturers in the table below.

Of course, it is almost impossible to completely avoid the risk of this disease. However, it can be minimized. In order to avoid this disease, before you start wearing lenses, you must find out whether you have any contraindications to this optics, and also strictly follow the wearing regimen of the products selected for you and be sure to replace the lenses if they are damaged, as well as the end of the recommended wearing period .

Which lenses are best for continuous wear?

Before the introduction of silicone hydrogel lenses, some hydrogel lenses received FDA approval for continuous wear. These include two-weekly replacement contact lenses Acuvue 2 from Johnson, quarterly replacement contact lenses Optima FW from Bausch + Lomb, etc. However, these days, these and similar hydrogel lenses do not meet modern requirements for lenses intended for continuous wear. The fact is that the use of contact lenses with low Dk/t (oxygen transmission) in this mode inevitably leads to hypoxic complications of the cornea.

It is known that the physiology of the cornea, its ability to absorb glucose necessary for energy production, depends on access to oxygen. This is explained by the fact that the cornea itself completely lacks blood vessels. In this case, oxygen saturation of the cornea in contact with the contact lens can be carried out in two ways: through the circulation of tear fluid in the space between the lens and the eye and due to the ability of the lenses to transmit oxygen.

Since the circulation of tear fluid in the under-lens space depends on the operation of the so-called under-lens pump, and during sleep in lenses it has practically no effect, for continuous wearing it is very important to choose lenses that can pass a sufficient amount of oxygen through them even with closed eyelids. If you use lenses for this mode, in which the cornea will constantly experience oxygen starvation, blood vessels will begin to form in it.

Their advantages

Daytime contact lenses for vision correction provide excellent quality of vision and comfortable wearing, as they are made using special technology that provides protection against discomfort. In addition to this, we can highlight other advantages of lenses intended for daytime wear:

• A high percentage of oxygen permeability, which allows the eyes to “breathe” and not experience oxygen starvation.
• The lenses are sufficiently moisturized due to the material from which they are made. It protects the eyes from drying out, so there are no unpleasant sensations during the day.
• The surface of the lenses is smooth, which prevents fat and protein deposits from accumulating on their surface.
• With proper care, there is no risk of discomfort, redness, allergies and dryness.
• The lens material does not irritate the eyes.
• The lenses are perfect for correcting both myopia and farsightedness.

Features of wearing lenses for farsightedness

With the help of these optical products, it is possible to improve vision even with a high degree of pathological process. Only the choice of optics needs to be approached more carefully, since wearing inappropriate devices will lead to a decrease in near visual acuity, the development of eye fatigue and the appearance of various consequences.

Advantages and disadvantages of optical eye aids for vision correction

Lenses cope with the task much better, which cannot be said about glasses. Thanks to the optics, high clarity of vision is achieved and excellent lateral visibility is maintained, distorting and not narrowing the image in front of the eyes.

The following advantages of such products can be highlighted:

• there is no need to carry them with you in a case;
• are able to correct even the last degree of hypermetropia;
• practical to wear, do not injure the organ of vision;
• wearing lenses, you can go to the gym or for a morning jog, while maintaining clear vision;
• the products do not cast glare and do not fog up; nothing can be said about glasses.

Disadvantages of products:

• a long period of adaptation, and sometimes people still cannot adapt;
• high price combined with frequent replacement of the product;
• high-quality care and compliance with storage recommendations;
• complications may occur.

Indications

The contact method is the only method of correction in patients with deviations in diopters of more than 2 units. Solid products are indicated in the treatment of astigmatism and keratoconus.

Are there any contraindications

The contact correction method is prohibited for use in the following cases:

• inflammatory or infectious processes affecting the eyes;
• increased production of tear fluid;
• allergic reaction;
• bronchial asthma;
• glaucoma;
• lens luxation;
• severe form of strabismus.

At what age can children wear it?

Optical therapy can be prescribed to children aged 10 years and older. Such a child can already put on and take off the products himself.

Wearing mode and replacement frequency

Basically, they use the daytime mode, when the lenses are worn from morning to evening, removing them only before going to bed at night. If we talk about flexible mode, then you can wear the optics for 1-2 days. Continuous wearing is only possible when using silicone hydrogel products.

Short-term, one-day products need to be changed every 1-2 weeks. But there are optics whose service life is 1, 3 or 6 months.

Flexible lens wearing mode

The improved properties of contact lens materials still do not provide a 100% guarantee that complications that are possible with continuous lens wear will not occur. According to the unanimous conclusion of the overwhelming majority of experts, the ideal option for wearing them is a flexible mode, when the lenses are removed at night, but if necessary, it is possible to sleep in them without fear for the condition of the eyes. This option is especially suitable if you use rigid gas permeable or soft silicone hydrogel lenses.

In the medical department, everyone can undergo examination using the most modern diagnostic equipment, and based on the results, receive advice from a highly qualified specialist. We are open seven days a week and work daily from 9 a.m. to 9 p.m. Our specialists will help identify the cause of vision loss and provide competent treatment for identified pathologies. Experienced refractive surgeons, detailed diagnostics and examination, as well as the extensive professional experience of our specialists allow us to ensure the most favorable result for the patient.

The cost of selecting contact lenses in our clinic is 1,500 rubles. Prices for other medical services at MGK can be found here.

You can find out the cost of a particular procedure or make an appointment at the Moscow Eye Clinic by calling multi-line phone 8 (daily from 9:00 to 21:00, free for mobile phones and regions of the Russian Federation) or using the online registration form.

conclusions

Constant wear lenses are designed to be worn continuously for thirty days. They are comfortable and safe for the eyes, they provide good oxygen permeability as well as eye hydration. With these lenses you can forget about daily care procedures. You can wear them around the clock and not worry about the health of your eyes thanks to modern manufacturing materials. Don't forget that before you start using permanent contact lenses, you must visit your ophthalmologist so that he can write you a prescription for suitable lenses. Incorrectly fitted lenses will be completely useless and can only worsen your vision.

Read this article about the causes of foggy eyes. Find out how to choose the right contact lenses here.