Rigid contact lenses for astigmatism. What are astigmatic eyeglass lenses. Astigmatic lenses: what is it, their types

Artificial vision is also vision

Technological progress and the development of information technologies are rapidly changing our lives and even physical parameters:

We grow taller and broader in the shoulders,
The overall life expectancy is increasing.

But:

Evolution does not keep pace with the increase in the number of computers and other sources of information that require prolonged strain on the organs of vision.

If in the last century ophthalmologists considered myopia and farsightedness to be the main diseases of the eyes, then with the development of medical science, they pay equal attention to the treatment of astigmatism, which patients consider an additional incomprehensible “scourge”.

Instead of glasses, lenses began to be worn relatively recently. But many took the lenses organically and practically abandoned glasses.

Now, when a new “misfortune” is discovered, patients ask a natural question about whether Can you wear contact lenses with astigmatism?

The answer of doctors of different specialties is unequivocal: it is possible and necessary!

The disorders caused by the diagnosis require correction. Contact lenses are the most common treatment for astigmatism.

Appointment, selection and benefits

In the polymer components of the lenses and in the lenses of the glasses, the rays are refracted with focusing on the retina of the eye.

Correction of vision in the presence of astigmatism is more difficult than with myopia and hyperopia. Therefore, only an ophthalmologist has the necessary qualifications and selects lenses.

During the examination of vision, the doctor determines the degree of astigmatism:

weak - up to 3 diopters;
medium - from 3 to 6 diopters;
high - above 6 diopters.

What to build on when choosing an optics material?

Astigmatic soft lenses are used for any degree of pathology.

Important: The use of soft optics is especially recommended if the number of diopters in one eye differs from that of the other eye by more than two units.

Even a large difference in visual acuity does not cause pain, while maintaining the possibility of equivalent binocular vision.

The choice of lenses depends on the lifestyle of a person:

sports,
the presence of extreme situations,
daily eye strain
the need to drive a car, etc.

Sports - to support health

Not everyone knows that lenses, like glasses, can be worn by children. Their appointment is especially necessary for babies who have congenital defects in the structure of the cornea.

Important: With this disease, correction from early childhood is extremely important, otherwise the child develops strabismus and other serious complications.

What are lenses for?

The use of lenses provides:

vision stability.
The absence of "blurring", headache and other sensations that arise as a result of defocusing of the eyes.
The fixed position of the lens eliminates the risk of shifting or falling out in extreme situations and when playing sports. Stabilization is achieved by technical solutions embedded in the form.
Visual acuity and peripheral vision create ideal conditions for driving, as well as for other work that requires good vision.
Improving vision at dusk and at night by wearing special "night" lenses.
Preservation of the natural beauty of the eyes.

Important: The use of multi-colored lenses does not affect vision, but changes the color of the eyes.

Types of lenses

Contact lenses are divided into tough and soft.

Important: Used to treat astigmatism soft toric lenses.

They are called TKL, because they have two meridians with different refractive indices.

The meridians are located at an angle of 90 degrees to each other.

SCL should be in a certain position in relation to the retina. The stability of the lens arrangement is achieved by their special shape.

Which firm to choose?

There is a huge variety of lenses. The doctor has the opportunity to select them individually, and the patient will choose from the recommended ones which are best for him personally.

Among the many options for the treatment of astigmatism offered by different manufacturers, the accelerated stabilization design is notable for Acuvue lenses. They are made by a company known for health products, Johnson & Johnson.

The material is synthetic silicone hydrogel, which:

allows for a long time to prevent the drying of the cornea,
retains ultraviolet rays that create additional stress.

Check out the products acuvue in more detail:

Types of lenses according to the method of application

Daily: used for a year, then they need to be changed. Removed for the night. Daily treatment with a cleaner and once a week cleaning from protein deposits is necessary. They have a low cost.
long wear: Used around the clock for a month. Cleaning and disinfection is carried out once a week.
Planned replacement: allowed to wear for three months with mandatory daily processing.
Frequent scheduled replacement, the price of which is the highest, do not require daily processing. They are prescribed for patients prone to allergic reactions. Terms of wearing - one, two, three, four weeks, depending on the model.

Contraindications for wearing

Medical appointments are a forced measure, which is due to the detected pathology in the patient.

Treatment of astigmatism is possible in various ways: glasses, surgery, exercises. Therefore, sometimes people do not understand why doctors do not advise wearing lenses for astigmatism.

Ophthalmologists explain their shortcomings:

As a foreign body, lenses can cause mechanical irritation with eye inflammation.
Oxygen starvation of the permanently closed cornea can cause increased myopia.
With different thicknesses in both eyes, optical distortions may occur.
Allergic reactions to polymers.

About vision correction with contact lenses:

What glasses to wear with astigmatism: the right choice of optical lenses

Those who have had to deal with nearsightedness or farsightedness are well aware that visual impairment can be conveniently and easily corrected with the help of contact lenses. This is a modern, safe and affordable way to effectively restore clarity of vision, which means the ability to fully work, study, perform household tasks and relax. But is it possible to wear contact lenses with astigmatism? This disorder is different from myopia or presbyopia.

Astigmatism contact lenses do exist and can be worn to improve vision. But they have their own characteristics in design and operation, in some cases they are contraindicated, therefore the selection of this type of CL requires a special approach and the mandatory participation of a specialist.

For information: astigmatism is a common visual impairment caused by the curvature of the surface of the cornea or lens. As a result, the light beam, falling on the eye, is incorrectly refracted and forms several foci instead of one. A person suffering from astigmatism sees everything in a blurry or bifurcated form. In most cases, mixed astigmatism is diagnosed, that is, combined with either myopia or farsightedness, such a pathology develops on its own extremely rarely. Previously, special glasses were used to correct astigmatism. Today, soft and hard contact lenses of various types are more comfortable and effective.

Description and features

With astigmatism, regardless of the severity of the pathology, it is combined with myopia or hyperopia, complex toric contact lenses are always used - TCL. These lenses differ primarily in design. Ordinary lenses are spherical, while toric lenses are spherical-cylindrical. The lens consists of two zones with different optical power: one acts along the meridian and corrects the curvature of the cornea in case of astigmatism. And the other one corrects a concomitant defect - myopia or hypermetropia. Even visually, they are denser and thicker than conventional CL.

Even an inexperienced patient will be able to notice the external difference between ordinary and astigmatic CLs.

If, when choosing ordinary lenses, the main parameter is the number of diopters, then lenses for the treatment of astigmatism are selected taking into account two additional values:

cylinder force;
cylinder axis.

It is very important to stabilize the SCL so that during operation they do not move in the eye. To do this, the lower edge of the lens is cut off or sealed. Then the lenses are worn for half an hour to check how well they are chosen, whether it is comfortable for the patient. If there are no complaints, then the lenses are chosen correctly, the doctor writes a prescription for them and makes an entry in the patient's card.

To correctly choose the optimal SCR, the difference in the refraction of the rays is taken into account. If it does not exceed 0.5 diopters, treatment and correction of astigmatism is not required. If the difference is 0.75 diopters and above, the wearing of special CLs is indicated.

Weak - TCL from 0.75 to 3 diopters will be required. With a weak degree of astigmatism, vision correction is possible in any way - with the help of laser surgery, ordinary glasses or soft CLs.
Medium - apply CL from 3 to 6 diopters. With this degree of corneal curvature, correction is necessary to prevent further complications and visual impairment. Surgical operations are expedient.
Strong - lenses more than 6 diopters are selected. Soft CLs are not suitable in this case, the doctor will select hard lenses that can correct and maintain the distorted shape of the cornea.

As usual, lenses for astigmatism correction are tinted, colored, colorless, biocompatible, with UV protection. According to the mode of wearing, they, like ordinary ones, are divided into:

one-day;
daytime, which need to be removed at night, disinfected and stored in a special solution in a container;
weekly - you can wear for six days and wear without taking off;
long-term wear - they are worn for up to one month, there are both day and night models.

Which of the listed types is the best can only be determined empirically, since the organs of vision and needs of each patient are individual, there is no single solution here. Today, CLs are considered the best way to correct vision, including astigmatism. Its main advantage is that the lens fits snugly against the surface of the eyeball and forms a single system with it. Whereas the lenses of the glasses are at a certain distance from the eye, which often causes a distorted visual image.

Almost every major manufacturer of optical products has toric CLs in their product line

People who suffer from even a low degree of astigmatism and use glasses rather than lenses are more likely to make mistakes in performing everyday household tasks, get into accidents while driving a car, and cannot move independently without injuries and collisions in the dark. Astigmatism without proper correction can lead to serious problems and accidents. Properly selected TKL in this case will be the best solution.

Useful information: for the correction of astigmatism, both soft and hard CLs can be selected. Rigid ones are more durable; with some diagnoses, only such types can correct a visual defect. But soft ones are more convenient to use, it is easier to adapt to them, they are practically not noticeable before our eyes. In addition, you can choose colored lenses for astigmatism, while hard lenses are mainly available only in a transparent version.

The main disadvantages of TCL

Most patients prefer to use CL for vision correction, as it is more convenient, effective and more aesthetic than the use of classic glasses. But at the same time, toric lenses have a number of features, because of which they are not suitable for everyone. Many users leave negative reviews about them and prefer to wear regular CLs as needed, without astigmatism correction, or continue to use glasses. The main reason is the complex and lengthy adaptation due to the thickness of the CL.

If the patient has never used contact methods of vision correction, it will be easier for him to adapt to thickened SCLs - he will not be able to compare them in operation with others. But if the patient used to wear soft regular CLs, and then switched to TKL, he will feel the difference and suffer from discomfort.

During the adaptation period, irritation and redness of the eyes, discomfort, dryness of the cornea may disturb - in this case, unpleasant symptoms will be softened by moisturizing eye drops

So, if you decide to try toric contact lenses, you should be prepared for such possible complications and side effects:

Since toric CLs are thicker than usual ones, when worn, they can cause discomfort, a sensation of a foreign body in the eye: even after a few weeks, adaptation does not occur.
An additional cylinder on the lens loads the organs of vision, the eyes in such lenses get tired faster than in ordinary ones. This is important for those who work at a computer all day or spend driving.
TCLs do not pass air well, because the cornea does not receive enough oxygen. This can lead to a change in its shape, which is why ophthalmologists recommend not to use TCL continuously, but to remove it at night. For many patients, this mode of wearing is uncomfortable.
If the diopters are different on the right and left eyes, optical distortions may occur when wearing the TCL.
With prolonged, constant wearing of cylindrical lenses, the shape of the cornea changes in patients, which leads to the formation of keratotonus. Keratotonus is a contraindication to laser vision correction, and the patient should definitely be aware of this if in the future he is going to correct the defect by this method.
Since cylindrical lenses are denser, in case of careless operation, it is easy to injure the surface of the eye when removing or putting on the CL.
TCLs have a significant mechanical effect on the eyes, therefore, if the patient uses decorative cosmetics, special hypoallergenic products should be selected. This reduces the chance of developing irritation.
Conjunctivitis, dry eye syndrome, corneal edema and irritation, ulcers and erosion are more often diagnosed in those patients who regularly use TCL.

In addition, there are a number of patient conditions when the use of contact lenses of this type is strictly prohibited. These include:

contraindications to refractive correction;
presbyopia (senile farsightedness) of any degree;
astigmatism 6 diopters or more, myopia up to 30 diopters or farsightedness up to ten diopters.

With individual intolerance to ordinary contact lenses, toric lenses are not prescribed.

It is worth knowing: despite the contraindications and a rather long list of shortcomings, modern, improved TLC for many patients has become a real salvation. People got the opportunity to continue to engage in their favorite sport, to fully work and relax. It is not necessary that the adaptation is difficult, and the lenses themselves cause eye irritation. If you follow all the recommendations for care and use, no side effects will occur.

In optics stores and online stores, you can easily purchase high-quality toric lenses in any price range.

Overview of the most popular models

Optix air. These are soft silicone hydrogel contact lenses that can only be worn during the day. A feature of this model is an extended optical zone, due to which the patient receives a clear image without distortion and displacement. Manufacturers have achieved the maximum possible thinness of the lenses, so that they do not cause discomfort even during the adaptation period and do not interfere after continuous 6-hour wear. But at night they should be taken out and disinfected.
Akuvyu oasis. All patients who wore this manufacturer's SCL noted comfort and secure fixation on the surface of the eyeball. These lenses effectively correct high astigmatism combined with nearsightedness or farsightedness. With sharp turns of the head, tilts, active movements during sports and even diving into the water, they are securely held in front of the eyes, do not change their position and do not distort the visual image.
Biofinity Torik. soft, silicone hydrogel contact lenses for astigmatism correction. They pass oxygen well and have a high level of moisture. The surface of the CL is treated in a special way, which prevents the accumulation of protein deposits, dirt and bacteria, and the growth of fungi.
Pure Vision 2 Torik. soft hydrogel SCLs with scheduled replacement once every thirty days. Thoughtful design eliminates spherical distortion, while the lenses are highly breathable, moisture-retaining and non-irritating. The peculiarity of this model: TKL can be worn only during the day, used in a flexible schedule (for example, wear for two or three days without taking it off, then pause for a day), or go in continuous wearing mode for seven days.
Biotru Van Day. These are disposable silicone hydrogel contact lenses for the correction of astigmatism. Buyers note the perfect fit of the lenses and complete comfort even after 16 hours. The big advantage is that this model does not require any care, including moisturizing drops throughout the day.

Most patients, having tried toric CLs once, no longer want to go back to glasses, despite the often occurring difficulties with adaptation.

Slight redness and swelling of the eyes in the first days of wearing new optical systems is normal. But if the redness does not go away after 5-7 days, the irritation increases, you should consult a doctor. It is possible that the selected TKL model is suitable, but the solution for caring for them causes allergies. Or the patient does not follow the rules for the use of contact lenses with astigmatism.

And it is also important to change lenses in a timely manner. By the end of the service life recommended by the manufacturer, the breathability of CLs is significantly reduced, and they also correct astigmatism and myopia worse. If you wear CL for longer than the prescribed period, the eye will swell, become irritated and inflamed, and fungal or bacterial infections may develop.

The solution for cleaning and disinfecting KL also has its own expiration date. It usually ranges from two to six months. It should be changed every day. and if the shelf life has expired, the solution has become cloudy, acquired an unpleasant odor, it is disposed of.

In no case should you wash TKL, and in general any lenses, with ordinary tap water, even if it is boiled. Do not use other antiseptic liquids or alcohol solutions for disinfection. And also you can not moisten the lenses with saliva. Such actions will immediately lead to inflammation of the conjunctiva.

Properly selected contact lenses for astigmatism can not only normalize the quality of vision, but also stop its deterioration in farsightedness or myopia

Astigmatism is a partial loss of the ability to see the world around. This is due to the appearance of a defect in the lens or cornea of the eye as a result of their deformation.

Due to falling on the retina streams of light have several focuses, and objects appear blurry. Therefore, the disease needs to be corrected, as it causes pain and redness in the eyes, accompanied by a headache and leads to the development of strabismus.

Wearing lenses for eyes with astigmatism

Astigmatism is corrected cylindrical contact lenses (CL). Use at any stage of the disease toric spherocylindrical lenses.

This is an effective and safe optical tool that fully compensates for visual impairment. Are made from vapor and gas permeable materials.

There are also disadvantages, consisting in a larger mass, which makes it impossible to use them for a long time. CL are characterized by the following parameters:

cylinder force;
the axis of the cylinder;
stabilization;
membrane;
period of wearing;
diopters.

Reference. Cylinder power needed to correct a defocused beam of light both vertically and horizontally. There is a correction of astigmatism directly along a given meridian, as well as the correction of pathologies of myopia and farsightedness along a certain horizon.

The axis of the cylinder is characterized by the angle of inclination of the astigmatism. He deviates 10-180 degrees depending on the shape of the lens or cornea. Stabilization of the angle prevents slipping of the shell of the contact product by creating specific shapes - thickening or trimming.

Orientation of these fixtures guarantees a tight fit, at which the light is scattered, creating a clear image. The chemical industry has various bonding methods.

Exist ballast lines with a sealed membrane, double- with alternating thick zones, as well as truncated at the bottom.

The surface of the contact product is colorless, tinted, tinted, colored and with a UV filter.

Wear time and diopter choose individually.

Important! Lens selection starts in the office at the ophthalmologist using biomicroscopy, visometry, refractometry, keratotopography. This takes into account the optical and astigmatic correction forces, the radius of curvature and the diameter of the cornea, the location of the defect, the type of stabilization (design).

The resulting recipe allows you to choose the right manufacturer for the preoperative period.

With a myopic form of pathology

Myopic astigmatism - most common form, combining the signs of myopia, when objects seem distant, and defocus, when the reproduced image is distorted.

This is because a small part of the light hits the retina, while the rest is focused at a point in front of it. Wherein observe the vagueness and bifurcation of silhouettes.

Photo 1. Scheme of focusing rays on the retina with normal vision (top) and with myopic astigmatism (bottom).

Wearing toric CLs is also mandatory. It is necessary to measure the control points at which the image destabilizes, and bend the horizontal axis so that the focus becomes clear. For this use high-precision equipment and test samples.

Is it possible to wear regular or colored contact products when sick?

Ordinary contact lenses are spherical not suitable for deformed cornea or lens. When worn, there will be a feeling of discomfort, redness and burning of the eyes. The focus itself will become even more blurry, which will not solve the problem. In addition, such products do not have multidirectional optical powers that bring the incoming light to the desired points. And free movement along the axis of the pupil will create a veil effect.

Colored spherical lenses have the same principle of operation, with the exception of aesthetic toric ones. They are saturating shade, creating a shade or fully colored.

Features of astigmatism correction with lenses

Toric or cylindrical lenses effectively correct astigmatism due to the special composition formula and shape. Each product has a sphere and a cylinder along a given axis, in which all light rays are collected.

At the same time, visual correction occurs by 2 meridians or optical powers, which are clearly fixed by the shape of the product.

Sometimes lenses cannot correct vision. Their use is limited period of time before the operation. Diagnosis reveals the type of treatment, which is complemented by laser retinal surgery or refractive lens replacement.

Astigmatic lenses: what is it, their types

There are two types of lenses that are used to correct astigmatism: soft and hard.

Soft

The basis for the manufacture of toric CL is hydrogel or silicone hydrogel. In the first case, oxygen enters the cornea through a tear, in the second case, directly through silicone, which is tightly attached to the retina. Therefore, hydrogel lenses are more prone to slip due to the accumulation of tears under them. it causes the focus points to shift. Such lenses are cheaper, poorly pass oxygen, but retain moisture under the shell, preventing protein deposition.

Rigid

These lenses are made of hard polymer materials. used during sleep. They can be oxygen permeable or oxygen isolating. Such products correct vision with closed eyelids which is reflected in their cost.

Photo 2. The principle of operation of hard contact lenses. Products during sleep smooth the surface of the cornea.

pros

With optical effects toric CLs almost do not distort vision, and not only binocular, but also lateral, and even contributes to the improvement of these indicators. And also they stabilize the light output in the presence of concomitant eye defects. And finally, they can be used in any weather and are suitable for active life.

Minuses

Astigmatic lenses can cause various diseases eye. allergic reactions determined by the material and storage solution. papillary conjunctivitis is the result of improper use. Corneal edema arise as a result of poor-quality fit and prolonged wear.

Photo 3. Papillary conjunctivitis, which is one of the complications of wearing lenses. Follicles form on the inside of the eyelids.

These side effects need timely elimination. Another disadvantage of lenses is limited oxygen access to the cornea, which can lead to myopia or changes in the topography of the cornea.

Selection of contact products

This issue is dealt with by an ophthalmologist. Wearing such means of correction is mandatory for astigmatism, as well as for cataracts, corneal diseases and after surgery. Therefore, various methods of modern electronic diagnostics are used. Be sure to take into account the age, lifestyle, health status and profession of the patient.

First thing measure axles and cylinders corrections, tilt angle relative to the horizontal for each of the eyes. Further, according to a special table, the necessary parameters are selected and a prescription is written out. Sometimes the surface of the cornea is severely deformed, which is why stabilization test. For this, the patient within 30 minutes reveals the degree of comfort of the product.

Differences between astigmatic and stigmatic lenses

Unlike astigmatic lenses, stigmatic have 2 spherical surfaces without a cylinder that refract light. In each meridian section they have the same optical power. The image is given by a focus with a certain power radius or diopters.

One focus is located on the outer surface, and the other is located on the inner. If you have astigmatism this shape of the product cannot correct distortion.

Therefore, astigmatic, combining spherical and cylindrical parameters are used.

Use of one-day optics

Disposable lenses made using the same technology as conventional. But their form includes all the parameters aimed at correcting defects. Such lenses are considered the most convenient for travel and replace the need to purchase a special solution.

How to choose visual correction tools for children

The main difference in choosing lenses for children is age. The stages of diagnosis of the disease correspond to the standard procedure. It is recommended to start wearing toric lenses at 7-8 years of age. when the child can understand the importance of hygiene and is able to independently use the vision correction tool.

Astigmatism is a specific change in the work of the eyes, in which everything around is seen with rather blurry boundaries or with certain distortions.

This disease affects people of all ages.

Often, astigmatism is combined with pathologies such as myopia or hypermetropia. Not so long ago, they were considered the most important pathologies of the eyes, but with the development of technology, more and more attention is now being paid to astigmatism.

In this regard, many patients ask the question: is it possible to wear lenses with astigmatism, how to choose and which ones are better?

Correct vision with the help of contact lenses began relatively recently, but already quite a large number of people prefer them rather than glasses.

Features of astigmatic CL

If astigmatism is detected in a person, the doctor writes a prescription for the purchase of special astigmatic or toric CLs.

There are stigmatic and astigmatic lenses on the market today.

The main distinguishing feature of toric CLs from ordinary ones is their shape. So stigmatic lenses for the correction of myopia have the shape of a sphere. While lenses for astigmatism are presented in a form that combines a sphere and a cylinder.

They have different optical powers that spread vertically and horizontally. On the outer meridian, one of the values corrects astigmatism, the second corrects the presence of myopia or hypermetropia.

Astigmatic SCLs are good at correcting disturbances in the perception of surrounding objects that arise due to different curvature of the cornea or lens. With such a curvature, the refraction of light rays in the vertical plane differs from their refraction in the horizontal. As a result, a person sees the world around him vaguely, and small details are illegible.

The second important difference between astigmatic and spherical CLs is their location on the cornea of the eye. In a spherical lens over its entire area, the power of refraction of light rays is equal. So, it does not matter how it lies on the cornea.

Toric lines must occupy a certain location. Only in this case, the cylindrical component will act on a specific area of the cornea. In the manufacture of CL are equipped with a special mechanism that fixes them in one position. This position does not change with blinking and head movement.

The following methods of fixing CL are distinguished:

prismatic ballast - in this case, the lower part of the CR has a large thickness as a result of gravitational forces, the lens remains in the correct position;
clipping or truncation - with this method, a small part of it is cut off for reliable fixation along the bottom of the lens;
periballast - in this case, the top and bottom of the line are made thinner;
various changes in the curvature of the anterior or posterior surface of the lens.

The best fixation is achieved by combining several methods of fixation. For the correct location of the SCL, the ophthalmologist focuses on certain laser marks.

Types of CLs that correct astigmatism

Today, there are a wide variety of toric lenses on the market for ophthalmic products from a variety of manufacturers. Acuvue and optics have gained the greatest popularity.

The following main types are distinguished:

Soft - these lenses are made from a thin polymer material. They are made in a special form that combines a sphere and a cylinder. As a rule, wearing this type of CL is regulated by the established regime, that is, they must be removed at night.
Rigid - for the production of this type of CL, solid materials are used. Astigmatism can only be corrected with gas-permeable rigid lenses. To correct astigmatism, these CLs are worn for at least six months. At night they should not be left on the cornea.

Important! When correcting astigmatism of the CL, one must carefully monitor the state of one's health. Since certain complications can develop with diseases such as diabetes, glaucoma or high blood pressure.

Manufacturers also produce colored lenses, which, in addition to correcting astigmatism, will change the color of the eyes. As well as multifocal, designed to correct this pathology in combination with farsightedness, provoked by the patient's age.

Advantages of CLs compared to wearing glasses

Until recently, astigmatism was corrected only with hard CLs. But progress does not stand still and even today people suffering from astigmatism can use special toric SCLs. Soft contact lenses with astigmatism can have an outer surface of a toric shape or an inner one. In the first case, the astigmatism of the cornea and lens is corrected up to 4.5 diopters, in the second case, the astigmatism of the cornea is corrected up to 6 diopters.

Compared to glasses, lenses win in the following ways:

correct astigmatism of the cornea to a high degree;
minimally limit the field of view and practically do not distort images on the retina;
provide the best conditions for lateral vision;
minimize spherical aberrations and prismatic effect;
allow you to achieve higher clarity of vision, because tightly adhering to the cornea, they create a single whole system of optics.

In addition to all of the above, a great advantage of CL is their production from the latest materials. Today, contact lenses of this type are made from hydrogel or silicone hydrogel. Both of these materials are remarkably tolerated by the cornea.

Wearing modes are also quite diverse - for one day, for two weeks, for 1-3 months. This allows you to choose the option that will be ideal for a particular patient.

Among other things, in order to get used to wearing CL, you need to spend less time than getting used to glasses.

Important! A prescription for the purchase of lenses to correct astigmatism is issued only after a complete examination and. Such lenses are prescribed only for astigmatism greater than 0.75 D.

Disadvantages of astigmatic contact lenses

With a large number of positive qualities, toric lenses still have some disadvantages.

These disadvantages include the following:

The development of the process of eye inflammation is possible - due to the greater thickness of these CLs, the patient may experience some inconvenience and may need more time to adapt to them. Also, when wearing lenses of this type, the patient's eyes can become especially sensitive.
Myopia may increase - this is due to a chronic lack of oxygen in the cornea.
The process of changing the topography of the cornea is possible - in this case, a specialist can diagnose keratoconus in a patient. This diagnosis may be a contraindication for vision correction with a laser.
It happens that various optical distortions occur - this is due to different thicknesses in different parts of the lens.

Important! With the help of CLs, it is possible to correct astigmatism, but they are unable to eliminate it. An experienced specialist should select lenses, taking into account individual characteristics in the structure of the eyes. Otherwise, their use may be harmful to health.

When deciding on the use of astigmatic contact lenses, the choice should be made on CL for one day or one month. They require a minimum of care and when used, the risk of inflammation is minimal.

Features of selection and cost of toric CL

When choosing lenses for astigmatism, the doctor spends more time compared to choosing ordinary SCLs in the form of a sphere.

Large expenditures of time are associated with the need to:

correctly selected spherical and cylindrical components for adjustment;
clarification of the existing axes of astigmatism;
mandatory assessment of the location of the astigmatic lens.

If the CL is located in the wrong place, the doctor will have to recalculate the astigmatic lenses.

These factors cause a higher price for the services of a specialist in the selection of toric CLs in comparison with conventional ones.

Also, the cost of this type of CL is affected by the complexity in their production.

However, when using astigmatic lenses, the patient sees the objects around him more clearly and better than when using cylindrical glasses or SCLs that have the shape of a sphere.

With the development of progress and various techniques, an increasing number of people are faced with the problem of astigmatism. A natural question arises: is it possible to wear contact lenses with astigmatism?

Recently, it has become possible to correct astigmatism with soft contact lenses. Such CRs have a special toric shape.

Due to the complexity in their manufacture, toric SCLs are more expensive. However, their cost is offset by a clearer picture that the patient sees in astigmatic CLs.

With astigmatism, the picture becomes blurry at close and far distances. A person with this refractive error constantly squints his eyes, due to which the lack of vision is partially compensated. Astigmatism is corrected with toric contact lenses. We learn what kind of contact optics it is and how to choose it correctly.

Why does astigmatism occur?

Violation of the refractive power of the eye, caused by its irregular shape, curvature of the lens or cornea, is called astigmatism. With this type of ametropia, bulges or, conversely, pits can be observed on the cornea. The lens or the entire eyeball is also curved. Because of this, light rays are not collected on the macula - the central region of the retina, but fall on two of its points at once. As a result, the picture is blurry. This is typical for vision at any distance.

There are three degrees of astigmatism. At the first, when the deviation is 1-2 diopters, a person sees quite well. Often, he does not notice the visual impairment, but reflexively squints, which temporarily improves the image quality. The second degree of pathology with a deviation from 3 to 6 diopters is characterized by diplopia, blurring of the resulting picture. With this form of the disease, headaches often bother, overwork occurs, symptoms of asthenopia develop. At this stage, it is rather problematic to do without correction of the refractive error. The third degree - a deviation of more than 6 diopters - is considered a severe form of the disease. The cornea is very strongly deformed. Often, such a defect can only be corrected through surgery.

There is astigmatism congenital, when hereditary factors become the cause, and acquired. Basically, the first form is diagnosed, which leads to abnormal development of the fetus in the womb: the gene that is responsible for the formation of eye structures, in particular the cornea and lens, is damaged. The gene is passed down from the father or mother. If one of the parents is its carrier, that is, suffers from astigmatism, most likely it will develop in the child.

The acquired type of this visual pathology occurs after eye injuries, operations on the organs of vision, eye diseases of inflammatory etiology. In rare cases, the cause of astigmatism is a disease of the dentoalveolar system. Some of them develop in parallel with the change in the shape of the walls of the orbits.

What are the difficulties in correcting astigmatism?

This refractive error is corrected with the help of spectacle and contact optics. When choosing a correction method, the stage and type of astigmatism are taken into account. Its light degree is corrected by cylindrical lenses or contact optics with an aspherical design. Complex forms of pathology, for example, mixed astigmatism, lenses with a cylindrical surface are not able to correct. This refractive error is often accompanied by myopia or hypermetropia. With myopia and astigmatism, the picture appears at two points in front of the retina. If astigmatism develops against the background of farsightedness, then on the contrary, the rays of light after refraction are at two points behind the plane of the retina. Only lenses with a toric design can fix this.

Cylindrical lenses for astigmatism

Spectacle lenses of a cylindrical shape, simply referred to as astigmatic, are visually cut along the barrel. Such optical products are equipped with positive diopters. The cast from this cut cylinder has a negative force. Two meridians can be drawn along the cylinder from its axes. One of them will be inactive. With a simple form of astigmatism, this is enough to provide clear vision. When it has a complex shape, correction along several meridians is required. Ordinary cylindrical lenses are not designed for this.

In some cases, patients are prescribed glasses with a complex design: cylindrical glasses are enclosed in spherical lenses. Such optics are able to cope even with the second stage of astigmatism, but it does not look very aesthetically pleasing. In addition, not everyone can tolerate glasses with similar lenses. Actually, almost all astigmatic glasses have to be adapted. At the first use, a person may feel pain in the eyes and other painful symptoms. In childhood, wearing cylindrical lenses with astigmatism is even more difficult. These glasses are heavier than usual. They will press on the bridge of the nose or fall off the face. The best alternative to such optics are toric contact lenses.

Toric lenses for astigmatism - what is it?

Contact optics are available in spherical, aspherical, toric and multifocal designs. With astigmatism, it makes no sense to wear ordinary lenses with a spherical surface. Such ophthalmic products do not always cope even with complex forms of myopia and hyperopia. In them, a person is concerned about distortions that form on the periphery of vision. Aspherical lenses prevent their occurrence. They expand the field of view, adhering more closely to the cornea and repeating its curved shape. They can compensate for astigmatism with a deviation of 1-2 diopters, but they do not correct the second and third degrees. This requires contact optics having a spherical shape.

Toric lenses can be represented as a ball, squeezed on both sides by hands. At the point of compression, the surface of the ball is more curved than on the sides, and from the outside it will have the shape of a hemisphere. There are two optical centers in such ophthalmic products. Light rays that fall on several points of the retina during astigmatism pass through both meridians, correcting not only the underlying pathology, but also the accompanying myopia or hypermetropia.

How are toric lenses selected?

With astigmatism, as with any other form of ametropia, lenses are selected with an optometrist. In addition to the standard set of parameters - the radius of curvature, diameter, optical power - the doctor needs to know the axis of the cylinder of future ophthalmic products that you will wear. It is also very important to choose contact optics with a suitable stabilization method. Toric lenses must be clearly fixed on the cornea. Even the slightest shift will degrade the image quality. Today, toric models of contact optics are produced with different stabilization methods:

Ballast use. With this method of stabilization, the lens has a slight seal on the bottom edge. When a person keeps their head straight, ophthalmic products are in the correct position. As soon as you tilt your head or change the position of your body, the lenses shift and the image blurs. These models are no longer produced.
Cutting off the edge of the lens, which is stabilized by the natural pressure of the lower eyelid. Such an ophthalmic product can also move, but already when blinking. A second later, it again takes the necessary position.
Periballast. Contact optics with this stabilization method have thin edges and four seals. Modern toric lenses are made mainly according to this principle. They do not restrict a person in movements. They can play sports.

Modern contact lenses with toric design - which ones to choose?

What lenses to buy for astigmatism? A few years ago, people with this vision pathology had to wear glasses that caused discomfort and looked unaesthetic. Now you can choose astigmatic contact lenses of any type. Even one-day models with a toric design are produced: 1-Day Acuvue Moist for Astigmatism. They are manufactured by Johnson & Johnson. They have a high level of comfort. Optical properties allow you to correct astigmatism, myopia, hyperopia of various degrees.

Monthly toric lenses are in demand. They are preferable for many, as they are much cheaper than disposable ones. At the same time, the optical and other parameters of such lenses are very high. This is evidenced by:

Biofinity Toric is developed by CooperVision. These lenses are made using Aquaform technology. They are 48% hydrated and have hydrophilic properties.

PureVision 2 HD for Astigmatism from Bausch + Lomb are ophthalmic products that guarantee the highest quality of vision even during intense physical exertion.
Alcon's DAILIES AquaComfort Plus are biocompatible lenses for people with corneal hypersensitivity.

- the most advanced toric lenses created from silicone hydrogel. Their oxygen permeability is 116 Dk/t, and their moisture content is 48%. They do not dry out and allow the eyes to "breathe".

Are colored lenses worn for astigmatism?

In principle, decorative contact optics are not contraindicated for people with astigmatism. However, toric colored lenses are practically not produced. There are two most famous models: Maxvue Vision ColourVUE Toric Gorgeous Gray (tinted) and Lunelle ES 70 Torique Couleur UV (colored). They are very expensive - about 20-30% more expensive than ordinary lenses, and therefore finding them is quite problematic.