Rus Articles Journal

Points down with! Laser correction of sight

As a rule, most of the people having problems with sight, for example, at short-sightedness, put on glasses or contact lenses. However recently more and more daredevils decide on surgical correction of sight. What does similar operation give? How she is had? Whether honestly that it is not sick at all?

the New opportunities

of Operation directed to correction of optical properties of an eyeball call

refraction because they change force of refraction of optical system of an eye expressed in dioptries. The majority of similar operations is performed on a cornea as it is the strongest lens of an eye.

Optics of eyes

a Human eye is similar

to a camera and consists of two important parts: optical (passing light) and touch (sensitive). An eye perceives light reflected from objects. At first it passes through optical part of an eye which represents system of lenses: cornea and crystalline lens. The strongest lens - a cornea (a forward transparent cover), it the first refracts the light beams entering an eye. Then light passes through a pupil - a round opening in a raduzhka which not only defines color of eyes, but also regulates pupil width. The pupil can be narrowed and extend thereby, regulating amount of light coming to an eye. Behind a pupil there is also a crystalline lens. A crystalline lens - the surprising lens capable to contract and finish, thereby focusing our look at the necessary distance - in bliz or in the distance. Normal the crystalline lens is absolutely transparent therefore it is not visible behind a pupil without special devices.

the Main objective of optical system of an eye - focusing of the considered image in the center of a retina - the sensitive cover covering an eyeball from within. The sensitive cages which are in a retina transfer visual information on nervous fibers to one nerve passing behind an eyeball. On this nerve information comes to a brain where there are an analysis and perception of the image.

the First refraction operations were carried out by

by means of the special surgical cutting tool making 4 - 12 radial cuts on a cornea (a radial keratotomiya or “a method of notches“ or “Fedorov`s method“). At first such operations were followed by a large number of complications, and many ophthalmologists were skeptical about this method of correction of sight. However as the technology of operation was improved, - the number of complications decreased to insignificant figures. During this time many people corrected the sight. However such method has a number of shortcomings. When performing similar operation sight became close to the desirable, but not always to ideal. In - the first, the result in many respects depends on experience and ability of the surgeon. In - the second, features of healing of cuts at each specific person not always allow to calculate the expected result precisely. Complications, such as dryness of an eye, decrease in sensitivity of a cornea, turbidity of a cornea, gaps in the area of cuts, though are rare, but nevertheless happened.

Now for refraction operations even more often use the laser. Laser surgery - one of the youngest and perspective directions of medicine. The laser is used in ophthalmology since the end 80 - x years of last century. Today more than 100 million laser interventions at various anomalies of a refraction (short-sightedness, an astigmatism) are around the world executed. In our country similar operations are performed since the end 90 - x years of the 20th century.

Ophthalmologists estimated at once possibilities of the laser which allows to influence with high precision a living tissue and to dose this influence. Unlike a radial keratotomiya, the majority of laser operations are carried out not on the periphery and in the optical center of a cornea. Thanks to it it is possible to predict more precisely effect of operation, and intervention became less traumatic. The essence of operation is that the laser “evaporates“ cornea cages, thereby, changing its optical properties. Operations of the laser cope the computer program that practically excludes any mistakes during operation. Accuracy and dosage of laser influence allows to cope with difficult options of violation of sight and to receive the planned result in 96% - 98% of cases.

Today two most widespread techniques of laser surgery exist: PRK and LASIK.

of PRK (in Russian - FRK, a photorefraction keratektomiya) is the first development of refraction laser surgery. Its essence - in the dosed removal of part of fabric of a cornea by means of the laser. The surface of influence remains open and begins to live within 2 - 3 days, at the same time the patient feels discomfort, dacryagogue and a photophobia are noted. It is easier for patient to be in the darkened room and the recovery period begins about 3 - 4 days. Within 1 - 3 months it is necessary to dig in drops.

of LASIK (in Russian - LAZIK, laser keratomilez) is represented by the most modern and most sparing type of correction of sight - it keeps anatomy of layers of a cornea. At the operation LASIK before influence of the laser the special device cut off a forward layer of a cornea and on a naked site of a cornea make “evaporation“ of its cages the laser. At the end of operation the cut-off rag is put on the former place. Edges of a rag and cornea stick together with each other - thus, integrity of a cornea is restored at once, and the patient should not feel discomfort.

- anomaly of optical part of an eye at which the light bunch entering an eyeball prepares for focus before a retina and therefore the image of a subject is projected by

of Miopiya (short-sightedness) on it not accurately. At short-sightedness the eyeball is excessively increased in the pereena - the back size (distance between a cornea and a retina). At young age when the eyeball is in a condition of active growth, an important role is played by excess visual loadings, heredity, a way of life. In other words, at short-sightedness the retina, as if moves away from a focusing zone. It is considered that each excess millimeter by which the eyeball grows corresponds to three dioptries of short-sightedness. Depending on extent of decrease in visual acuity distinguish: weak miopiya - to - 3 dioptries; an average miopiya - to - 6 dioptries; a strong miopiya - more - 6 dioptries.

Safety of any of refraction operations depends on its complexity, experience of the surgeon, size of risk of postoperative complications.

the Fulfilled technology of carrying out similar operations minimized possibility of side effects and complications. Besides, the modern level of inspection of the patient before operation does probable risk of complications minimum. Besides every year the equipment used to production of refraction operations is improved.

treat the most widespread complications of laser refraction operations: not full correction of sight (sometimes incomplete correction is the planned result of operation) or hyper correction (from gr. hyper - over), distortion of objects in twilight (at operations on high degrees of anomaly of a refraction), postoperative hypostasis, turbidity of a cornea, etc. All this leads to decline in quality of sight and in certain cases demands repeated operations. Let`s note that at the operation LASIK errors are possible during formation of a rag (for example, its gap or a separation, uneven thickness), the wrong fixing of a rag, shift, bad adhesion of its edges, etc. And also, from - for the fact that manipulations are made in deep layers of a cornea such complication as keratokonus, i.e. protrusion of a cornea in the form of a cone which top gradually grows turbid can develop. Sometimes at a keratokonus there is a hypersensibility of a cornea which is followed by pain and a photophobia. Simpler and, respectively, safe operation, from the point of view of the frequency of emergence of vnutrioperatsinny complications, is PRK as it is not connected with performance of cuts of a cornea, does not demand high surgical skills. LASIK are more dependent on experience of the surgeon and hardware. But they yield more predicted result in the postoperative period. And PRK in many respects depends on features of healing, individual at each patient. Besides, if the patient has a high degree of short-sightedness, then after PRK gradual partial return of a miopiya within 1 - 1,5 years after operation is possible. it is important to p to remember

that all similar operations correct only optical system of an eye, without curing of complications by which various violations of sight can be followed. For example, at short-sightedness, from - for superfluous lengthenings of an eyeball food and structure of a retina can suffer that threatens further with its peeling - in this case urgent special operation is required.

to

to Whom will be helped by the laser?

of the Indication to treatment of anomalies of a refraction by means of the laser - first of all, this desire of the patient to get rid of points and contact lenses. This the most important and in most cases only indication. However some violations of sight cannot be eliminated completely by means of points and contact lenses (for example, an astigmatism of high degree). And in this case the laser surgery can be the only method of restoration of sight.

people who lead the active lifestyle not compatible to glasses wearing and contact lenses, or the people wishing to refuse points for cosmetic reasons Also resort to the help of the laser. Some patients perform operations from - for career a reason, for example, at employment in the organization where on features of a profession 100% sight are required. Anyway the decision on carrying out operation is initially made only by the patient.

Should noticing

that as the purpose of refraction operation - disposal of points and contact lenses, it is possible to consider it cosmetic. Therefore, insurance companies do not pay similar operations, and all expenses lie on the patient. The price depends on extent of violation of sight. On average one eye operation can manage about 10000 rubles.

After operation sight changes qualitatively: it will become more volume, wide - points of similar effect cannot provide. The difference that will be more noticeable, than extent of violation of sight is higher.

However exists also a number of contraindications which should be considered, being solved on laser correction of sight.

Absolute contraindications (carrying out operation under no circumstances is impossible):

  • the congenital and acquired immunodeficiency;
  • only eye;
  • the progressing short-sightedness;
  • glaucoma (the chronic disease of eyes which is followed by increase of intraocular pressure and decrease in sight;
  • a cataract (an illness of eyes which main display is partial or full cataract with decrease of visual acuity up to its full loss);
  • thinning of a cornea;
  • the operated otsloyka of a retina (for LASIK);
  • tuberculosis;
  • oncological diseases;
  • venereal diseases;
  • pregnancy and lactation.

Relative contraindications (carrying out operation is possible under certain conditions):

  • diabetes;
  • mental diseases;
  • sharp and chronic inflammatory diseases of an eye;
  • the getting cornea hems;
  • the expressed changes from an eye bottom.
Preparation for operation

Discuss

with the doctor in advance what your way of life after operation will be. Frequency of surveys and those eye drops which should be used after operation. It is necessary to discuss all from the mode of visual loadings, restriction in physical activities (for example, a raising of weights, inclinations) before use of cosmetics. All this is solved strictly individually. For the period of treatment it is desirable not to change a hormonal background. For this reason do not advise to carry out laser correction of sight during feeding by a breast, and also for half a year before the planned pregnancy - the changing hormonal background can affect a current of the postoperative period. Discuss possible reception of hormonal contraceptives (oral contraceptives) with the doctor. Also it is worth discussing possible reception of other medicines and vitamins. Try to take vacation for the period of carrying out operation. It will allow you to be under control of the doctor at first after operation. All week preceding operation it is necessary to go without contact lenses - only wearing spectacles. A day before the appointed day it is necessary to wash up carefully the head and a face and to refuse cosmetics and a make-up. If laser correction of short-sightedness important that violation did not progress is planned. Otherwise, even successfully performed operation does not guarantee long-term effect: after a while short-sightedness developed from again - for the continuing lengthening of an eyeball. To be sure that short-sightedness does not progress it is necessary to pass inspection at the ophthalmologist twice with a difference not less than half a year. Besides, it is necessary to know that at correction of short-sightedness surgically, after 40 - summer age perhaps all the same it is necessary to use points for reading as from - for processes of aging of eyes begins to focus worse close.

the Astigmatism
- eye refraction pathology at which sphericity of a cornea is broken (its surface uneven) the image on a retina is focused by

differently in different meridians. As a rule, at an astigmatism there are two meridians, in one of them the cornea refracts stronger, in another is weaker, usually these meridians are located at right angle. The image of a subject is projected on a retina differently in different meridians and it turns out indistinct. What leads to decrease in sight. The person at the same time sees objects distorted in which one lines accurate, others - indistinct. The reasons of emergence of an astigmatism are up to the end not studied. In most cases this pathology has the congenital and inherited character. The astigmatism reason can also become eyeball operation and centuries or eye injuries.

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In all clinics before appointing laser correction of sight, conducts examination. Usually it takes about two hours. The ophthalmologist checks sight, sight with optical correction (wearing spectacles or contact lenses), removes the detailed topogram - the map of a cornea where all its optical parameters are displayed. Then the doctor describes to the patient all features of a condition of eyes, tells how there will take place operation and what feelings are probable after operation. Operation can take place also in day of inspection.

It is silent, there is an operation!

All operation takes with

only several minutes. It passes without anesthesia, but at the same time the patient feels nothing - the doctor digs in special drops thanks to which an eye is completely anesthetized.

before procedure try to calm down. Application of sedatives is sometimes possible. But it is better to communicate previously to those who already underwent a similar operation once again to be convinced that everything will be painless. During operation it is necessary to concentrate on accurate implementation of instructions of the doctor.

the Recovery stage

Visual functions are restored by

in 2 - 3 hours after operation, but final restoration of sight comes in 1 month.

is forbidden to touch with

Right after operation an eye, the sharp movements are not allowed by an eyeball, eyelids need to be closed quietly, without squeezing.

Practically right after operation can go home. It is better always to ask relatives to accompany the patient after operation and to take him to the house by car. Krome if to reach the residence by public transport, there is a risk to catch viral conjunctivitis (an inflammation of a mucous membrane of an eye). Sometimes, depending on a type of operation, the doctor advises within 1 - 2 days to observe the house mode. In some clinics after laser treatment insist on the temporary termination of alcohol intake.

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As a rule, after operation appoint gymnastics for eyes which promotes the fastest restoration of accommodation - abilities to see both close, and in the distance. In the first two weeks after operation it is necessary to dig in eye drops, visual and physical activity needs to be limited, it is desirable to wash a face and area of eyes with boiled water without use of cosmetics which can be applied approximately in a week after operation and only with the permission of the doctor. Within a month long bathtubs, visits of a bath and the pool are not recommended.

If all recommendations are implemented by

, then it will be shortly possible to enjoy new quality of sight without any restrictions.