home Analyzes The history of laser vision correction. Vision correction surgery – simple, affordable, safe, effective

The history of laser vision correction. Vision correction surgery – simple, affordable, safe, effective

I’m probably writing for those who really poor eyesight and who is afraid and wondering whether to have surgery or not.

My vision began to deteriorate in kindergarten. And when I went to school, each school year took it away from me more and more. As a result, by the age of 14 I had progressive high myopia degrees - vision-7, clouding of the lenses, astegmatism.

I was prescribed glasses back in science classes, but I didn’t wear them, I had a terrible complex. And the older I got, the more these complexes grew. In high school, I only wore glasses for tests; the rest of the time I saw the world like a blurry movie. Further than a meter, everything for me was streamlined and cloudy, just a constellation of blurry colors. I felt extremely uncomfortable wearing VP glasses. Especially when I entered the premises from the street, transport. My glasses immediately fogged up and I was left in complete disorientation and darkness. And of course, the toughness of teenage classmates. There were two bespectacled people in our class - me and another girl. They mocked us horribly. They hid our glasses, but we couldn’t find them because we couldn’t see anything without them. They deliberately broke the chokes, etc. Later I learned to guess people by their voice and even their smell)) At the age of 15 at the Lyceum I played volleyball and hit the ball according to the approaching sound, and successfully))

From the age of 17 I began to wear lenses; they were always selected for me by an ophthalmologist in Regional hospital. That is, not in shops, but with a professional, who spent two days with me full diagnostics vision and selection of exactly the right lenses for me.

When I first put on the lenses, it was a shock. Everything is clear and bright. I hadn’t seen so much before, I didn’t know how bright and beautiful this world could be. It was a delight! But my happiness did not last long. The lenses caused me terrible discomfort - a constant feeling foreign body In eyes. My eyes were constantly swollen, inflamed, and watery. The doctor tried to find me other options - more expensive, imported, etc. But my eyes reacted the same to any lenses and solutions.

The trip to the subway was especially torture for me. For some reason, it was there that I experienced the most terrible sensations. My eyes stung terribly, tears flowed. And when an eyelash or dust, sand, etc. got into them, it was real hell! You cannot put your fingers into the lens, but if something stuck to the lens, the pain was unbearable. When you can’t walk, you’re lost in space, tears streaming down your face, your eyes reddening! Once I tried to catch something that got on the lens and ended up leaving a cut on it. I had to urgently go to the hospital and change the lenses for new ones.

My always inflamed eyes, and when without lenses at all, almost zero vision prevented me from spending my young years the way I wanted. I couldn’t go to a club at night, go on overnight hikes with friends, and in general, as I realized later, I often didn’t notice male gazes on me precisely because I simply didn’t see them.

My ophthalmologist tried her best to dissuade me from having laser correction. They say that surgical intervention is always dangerous, you may be left without any vision at all. BUT when, by the age of 23, I developed corneal dystrophibus with the help of lenses (the lens constantly had a mechanical effect on my eyes), I changed my mind. It was scary. FOR 3 months I practically lost my sight. There was terrible swelling. The doctors couldn't even find glasses for me. With the most powerful diopters, I could not see even the largest letters on the table. I remember how my husband was leaving for work, and I was trying to cook dinner and cutting my hands with a knife. I saw practically nothing. After 3 months, when I managed to cure the corneal edema, I decided to have surgery.

Yes, I was terribly scared. They were around me good people who said that after the operation I would remain blind, etc. BUT, accidentally talking with a neighbor, she said that a couple of years ago she had surgery in Excimer with a specific doctor and was happy. She gave me his number.

How we raised money for this operation is a different story. We had a certain amount. After reading their prices, I estimated the amount for progressive myopia and was sure that it would be enough for me.

The doctor at Excimer diagnosed me and said that my case was terrible. That he does not want to take on such a thin cornea, there is almost none left. Said the lenses have done their job over the years. I burst into tears. Lenses were now contraindicated for me, and glasses, even made from good imported (whatever the name is) material, were thick and ugly. The doctor shook his head, sighed and said, if I had less experience, I was still 5 years old, I wouldn’t have taken it, but now I’ll take the risk. But you must clearly understand that surgery may not help you. You won’t be left completely blind, but I don’t promise to return your sight to you either. I agreed to everything. He calculated my cost and it came out to 20 thousand!!! in those years it was a large sum more expensive than what I was counting on. I'm in tears again. EVEN my mother, who was sitting next to me, shed tears. She knew how much I suffered and how I dreamed of healthy eyes. -Well, what is it again? asked the doctor. I told how long we had been saving this amount, how we borrowed, got out, and how much I had in my hands. And imagine, he agreed! He sighed again and said, “I hate it when women cry.” He wrote on all the documents that I paid 60 thousand, but in fact there were only 40. Just don’t even think about telling anyone about this, he told me.

On the day of the operation, I was terribly anxious and did not sleep all night. When I arrived and was waiting for my appointment, suddenly the lights went out in the clinic and the operation had to be postponed. It was a bummer. It seemed as if the entire universe was against my being able to see.

But a week later the operation took place. It was painful. Yes. There was a smell of logs, a laser blasting into the eyes. I moaned and twitched, but soon it was all over.

I remember walking out to the car after the operation. It was spring and sunshine. And this sun was killing me. The pain in my eyes was unbearable, I almost groped my way to the car. It was impossible to open my eyes. I felt this pain for two more weeks after the operation, but it became less and less every day.

And then the magic began)) My vision began to return to me a little every day)) At night, I opened my eyes and every time I looked at the pattern of the curtains, I saw it more and more clearly. These days could be compared to a child's anticipation of the New Year. When the aroma of tangerines is already in the air, when a letter to Santa Claus has already been written, and you wake up every night and hope to see him come and hide a treasured gift somewhere.

Each new day brought new colors and shapes into my life. Out of habit, I still tried to find my glasses on the table in the morning, and then smiled and opened my eyes, enjoying what I could now see with my own eyes!

After some time, I had another operation to strengthen the retina so that after childbirth my vision would not deteriorate. This operation was not so scary, but also unpleasant. It felt like my head was being drilled.

My doctor said that one of my eyes sees perfectly, and the other is just a little worse. According to the contract, I had the right to demand another correction for free, but the doctor dissuaded me and said that this time there might not be enough corneas. I didn't want to. I didn’t feel that one eye saw a little worse than the other.

8 years have passed since then. I gave birth to two children. My vision hasn't deteriorated one bit. I still have dreams in which I see the same as before - everything is blurry and unclear. And then in my sleep I start to panic, I squint my eyes, I try to concentrate, but nothing comes of it. And in a dream I understand that I have lost my vision again and I am overcome by panic and terrible melancholy. These dreams are very frequent and after them I wake up in constant fear. And only when I open my eyes do I realize that it was just a dream.

I am very glad that I decided to take this step. All my complexes are gone, I am able to see the world in all its colors, I began to see the looks of men on me)) I can walk at night with my husband and go on overnight hikes, live full life! And I am incredibly grateful to the doctor who risked ruining my sight and did not refuse me when he realized that I did not have enough money.

Therefore, girls, I do not encourage anyone to do anything, let everyone draw their own conclusions. Whether you need it or not. Just sharing my story.

Hello, dear friends!

Still, thoughts about laser vision correction do not leave me alone. I can’t even believe that you can get rid of eye problems once and for all, break your glasses, flush your lenses down the toilet and live a full life.

“But this is still an operation, an intervention in the body. Think 100 times!” - Mom warns me.

“The correction costs money. What if it doesn’t help? - the husband is being miserly.

"Maybe, better exercise all sorts of drops, vitamins?” - whispers a cautious inner voice.

My dears, my dears!!! Where does this pessimism come from? Read this one most interesting article, you will learn that the history of laser vision correction goes back 30 years, and during this time the technique of performing the operation has been perfected. Do you also have doubts, dear readers? So, you should also study the information from this article.

Apparently, the issue of the safety of operations to restore vision occupies one of the main places in the minds of Russians.

Laser correction, the most popular method of correcting myopia, farsightedness and astigmatism, is the subject of a lot of articles and studies, and is discussed by visitors to numerous forums and blogs. And among adequate and truthful information they often slip various kinds conjectures and judgments that truly frighten the inexperienced reader seeking the truth.

What you won’t learn from the messages of well-meaning online visitors: it’s harmful, it’s painful, and during correction they remove a layer of the cornea, but the problem ITSELF is not eliminated, and you’ll have to wear a blindfold for several months, and you can’t do laser correction nulliparous women, and then the vision drops again... Horror, Horror, I want to close my eyes and, exhaling, say: “No, I won’t let you cut my eyes, I’d rather look like that!”

Cut your eyes! Where did this even come from? And who came up with horror stories about bandages, the lack of statistics on laser corrections and other misconceptions? It’s difficult to answer this question, but in order to establish the truth once and for all, let’s turn to an irrefutable source: the history of the issue.

Radial keratotomy

So, the first method of vision correction called “radial keratotomy” appeared back in the 30s. last century. Its essence was that incisions were applied to the cornea of the eye (from the pupil to the periphery of the cornea), which subsequently grew together.

As a result, the shape of the cornea changed and vision improved. However, these first vision correction operations were accompanied by many serious complications (one of them was clouding of the cornea, leading to loss of vision).

The accuracy and stability of the result of such vision correction also left much to be desired, since the speed of healing depends on the individual speed of regeneration of the cells of each person’s body - some can boast that their wounds heal instantly, while others are forced to walk with a bandage for weeks due to for the slightest scratch...

And besides this, the surgeon’s instruments were often far from micron precision. It was this method that gave rise to many rumors and prejudices that frighten people of the 21st century.

This method received a new life in the 70s, when it was improved by the famous ophthalmic surgeon Svyatoslav Fedorov. New diamond instruments and microscopes have already appeared, allowing the radial keratotomy method to move to a qualitatively new level.

However, this technique still required a long period of rehabilitation, and was often accompanied by complications; the patient could lose vision from accidental stress during any load. Well, the question of the predictability of the result and the accuracy of its execution still remained open.

Few managed to obtain the desired “unit”. This is where the roots of many prejudices about laser vision correction come from. Therefore, trying to find another way to return good vision, were not abandoned.

The history of the excimer laser, actively used in modern ophthalmology, begins in 1976. Then the attention of medical scientists was attracted by the developments of IBM Corporation. IBM specialists used laser ray for engraving on the surface of computer chips. This procedure required truly jewelry precision (down to microns). Therefore, this know-how seriously interested doctors.

As a result of the research, doctors have established that the safety of using a laser beam and the ability to control it in depth and diameter of the impact zone is of particular importance in such a delicate area as refractive surgery. And the triumphant march of laser vision correction technology began.

In 1985, the first laser vision correction using the PRK technique was performed. As with radial keratotomy, the cornea of the eye was directly exposed. But the principle of influence was completely different. No notching was required. The shape of the cornea changed under the influence of a laser, which evaporated tissue from its surface and formed a new surface.

High accuracy made it possible to achieve good predictability of the result, a significant reduction side effects vision correction. But for the patient, the period of restoration of the surface layer (2-4 days) was extremely unpleasant, and adaptation ended only after 3-4 weeks. But, despite this, the patients were very satisfied, because the acquired excellent vision made it possible to very quickly forget about these unpleasant sensations.

Lasik technique

The most popular Lasik technique today appeared in 1989. Its main advantage was that the superficial layers of the cornea were not affected, and the evaporation of corneal tissue occurred from the middle layers.

This laser correction method has become a real revolution in refractive surgery, and today LASIK allows vision correction to be performed under local anesthesia in a few minutes, significantly reducing the recovery period.

During correction using special device— a microkeratome bends the surface layer of the cornea 130-150 microns thick, after which the laser evaporates part of the cornea and the flap is placed in place. Restoration of the epithelium along the edge of the flap occurs within a few hours after correction, and it is securely fixed; the patient immediately notices a significant improvement in vision. Its sharpness is finally restored within a few days.

LASIK technology has undergone multi-stage clinical trials before it began to be used in ophthalmological centers and clinics. Long-term observations of patients have shown that the excimer laser does not cause any disorders, since the impact occurs only on one of the refractive media - the cornea, and the depth of impact is strictly limited.

They are working with her today medical centers and clinics in 45 countries. Over the past 10 years, about 5 million vision corrections using the Lasik technique have been performed worldwide. In the USA and Japan, the procedure for restoring vision using laser vision correction has long gone beyond specialized clinics.

Often small laser correction centers can be seen in the territories of large shopping and entertainment complexes, next to dental and cosmetology offices and beauty salons. The patient undergoes a vision diagnosis, and then, according to the data obtained during the examination, the doctor makes a correction.

In addition, the US government, as part of the National Armed Forces Improvement Program, year after year pays for laser vision correction for military personnel of all ranks and branches of the military.

High level of procedure safety and advanced laser installations latest generation made the laser correction procedure simple and accessible to everyone. Of course, we must not forget that like everyone medical method, laser correction has some contraindications and limitations. It is not recommended for people suffering from:

But for those who can restore their vision using this technology, the correction becomes a real salvation. After all, it is an incomparable pleasure to look and see every day the world bright and clear.

Among the thousands of people who have undergone laser vision correction, there is not a single one who would at least once regret their decision to give up glasses and contact lenses. Former patients ophthalmologists often admit that only after laser correction did they begin to feel like full-fledged people.

It's so nice to not care about the fact that you might not see something. Having made the correction, they persuade all their visually impaired friends to do this feat. And they, in turn, then wonder why they were so poorly persuaded and could not be convinced earlier?

The truth about laser correction is that it really helps get rid of nearsightedness, farsightedness and astigmatism. Today it is the most reliable and perfect way to restore vision, allowing you to forget about glasses and contact lenses once and for all!

http://excimerclinic.ru/press/true/

Day of laser vision correction surgery through the patient's eyes

DAY OF OPERATION. This is how one patient describes LASIK laser vision correction surgery.

9.30 This morning I find myself away from cosmetics and perfumes, which is mandatory for eye surgery. I haven't worn it for two weeks now contact lenses so that the eye returns to its normal state before surgery.

10.00 After light breakfast, I leave the house accompanied by my husband. During the operation he will wait for me and then take me home.

11.00 ARRIVAL at the clinic
"Good morning, how are you?" They greet me warmly at the reception. Yesterday I wrote a statement of consent to the operation. I have no more questions, and I am invited to the reception department.

11.10 Brief eye examination. The doctor checks my eyes one last time before surgery.

11.20 In the preparation room I receive a cap and shoe covers that I need to wear during the operation. Then they put medicine in my eye to local anesthesia and disinfect the skin around the eyes. "How are you feeling?" the nurse asks me. She offers me depressant from possible nervousness.

11.30-11.50 OPERATION
I go to the operating room and lie down on the bed. The doctor opens my eyes and instills eye drops into me again.

11.45 I feel a brief pressure, it becomes dark, the eye is treated with a microkeratome knife. Then it becomes light again and I can hear the laser working on my eye. I do not feel anything.

11.50 Having finished the work, the doctor asks me: “Are you feeling well?” I feel good and can already get up. The doctor checks the result of the operation using a special lamp - he is happy with everything.

11.55 I can leave the operating room and change clothes. Then I sit on the sofa in the clinic lobby and relax. Laser eye surgery is over. A polite nurse offers me coffee.

12.15 The operated eyes are checked again. Everything is fine! I get antibiotic eye drops and some simple tips.

12.20 WE ARE LEAVING

"Bye see you tomorrow!" — the receptionist says goodbye to me after she has scheduled my follow-up visit for the next day.

http://www.cvz.ru/laser-correction/operation-laser/den-operacii-glazami-pacienta/

The doctor Barraquer first proposed surgery to treat myopia in 1949. To do this, he removed part of the cornea using a knife. Subsequently, the corneal disc was frozen and then ground down, changing its shape. Since the accuracy of the operation was low and the result was not stable, keratomileusis did not become widespread. Also, after surgery, clouding of the cornea often occurred.

After this it was proposed surgery for the treatment of myopia, which consists of applying radial incisions (radial keratotomy). In this case, 4-12 incisions are made through the cornea, which heal through scarring. This causes the central part of the cornea to become flatter and the focal point to move closer to the plane of the retina. This type of correction was used until the late 1980s, but it was also not accurate and had many disadvantages. For example, due to a loss of strength, the cornea could burst in the incision area during an impact. Also, over time, the result of the operation decreased, and astigmatism could not be cured in this way.

Since the end of the last century, thermokeratoplasty has been proposed for the treatment of farsightedness. In this case, point coagulations were applied to the peripheral zone of the cornea using a thermal laser or a hot tip. After this, pinpoint scars and opacities formed along the edge of the cornea. The central part became more curved. The effectiveness of the operation was unstable and inaccurate, so it did not receive widespread. In addition, there was an excessive damaging effect on the cornea.

No laser was used in all of these operations. The excimer laser was first proposed for corneal ablation in 1983 by Trokel. These lasers operate due to an excited dimer (a noble gas halogen atom) that decays and releases a high-energy ultraviolet photon. In this case, living tissues are exposed to an influence that leads to the breaking of intermolecular bonds, that is, the solid becomes gaseous. This is the phenomenon of so-called photoablation. There is no thermal effect on cells during ablation.

The excimer laser was first used to treat myopia in 1986 by a team of doctors led by Marshall. This operation is called photorefractive keratectomy. Then it became a real breakthrough in the correction of myopia and was used to treat weak and medium degree visual impairment. Using PRK to correct myopia and astigmatism high degree led to the frequent development of side effects (corneal clouding, residual ametropia).

In this regard, scientists began to develop methods for correcting myopia exceeding 6 diopters. As a result, LASIK was developed, whose history begins in 1989. It was then that doctor Buratto performed the first such operation. The main difference between LASIK was the preservation of the superficial layers of the cornea with ablation of only stromal elements.

LASIK has been successfully used to correct severe myopia and astigmatism. The equipment used during the operation is improved every year, so the risk of complications is also reduced.

An important stage of LASIK is the formation of a superficial corneal flap, for which a special microkeratome is used. The success of the entire operation often depends on the model of this device. IN last years For this purpose, they also began to use a laser (femtosecond), which makes it possible to perform LASIK surgery in a completely non-contact way.

During active implementation in ophthalmological practice femtosecond laser, German scientists have developed a fundamentally new method of laser vision correction. In 2006, doctors V. Secundo and M. Bloom proposed cutting a lens with certain parameters from the corneal stroma and then removing it through a micro-incision. The ReLEx SMILE technique avoids the formation of a corneal flap and does not cause displacement of the surface layers. That is, in one stage, using only a femtosecond laser, it is possible to restore vision even if it deviates significantly from the norm. After the SMILE operation, the biomechanical stability of the cornea is maintained, and recovery period does not exceed 1-2 days.

- Evolution of vision correction methods

Evolution of vision correction methods

History of the development of vision correction

Vision correction - website

The oldest method of vision correction is, of course, glasses.

During excavations in Troy and Crete, optical lenses made of rock crystal were found, which theoretically could be used as optical instrument for vision correction. According to legend, the Roman Emperor Nero used optical lens made of emerald for vision correction. Glasses, in the modern sense, are about 600 years old., it was from the end of the 13th century that medical treatises mentioned glass lenses for vision correction. The author of this invention of a non-surgical method of vision correction remains unknown.

The search for a method that would help a person regain good vision began a long time ago. Glasses and contact lenses are temporary means of correcting the loss of vision and they have never fully satisfied those who were forced to wear them. Already in the 19th century, works were published on the possibility of correcting vision as a result of exposure directly to the eye itself.

The first method of vision correction by influencing the cornea of the eye is radial keratotomy. It appeared back in the 30s. last century. Its essence is that deep radial incisions were applied to the cornea of the eye (from the pupil to the periphery of the cornea), which fused together after the operation. As a result, the shape of the cornea changed and vision improved. However, the first vision correction operations were accompanied by many serious complications (one of them was clouding of the cornea, leading to loss of vision). The accuracy and stability of the results of such vision correction left much to be desired. And besides this, the surgeon’s instruments were often far from micron precision. It was this method that gave rise to many rumors and prejudices that frighten people of the 21st century.

New interest in this method arose in the 70s, when it was improved by the famous ophthalmic surgeon Svyatoslav Fedorov, a new diamond instrument was invented, and microscopes appeared that made it possible to monitor the progress of the operation. However, this operation still required a long period of rehabilitation and was often accompanied by complications; subsequently, the patient could lose his vision due to unexpected stress during any load. Therefore, attempts to find another way to restore good vision were not abandoned.

The history of the excimer laser, actively used in modern ophthalmology, began in 1976. Then the attention of medical scientists was attracted by the developments of IBM Corporation. IBM specialists used a laser beam to engrave the surface of computer chips. This procedure required truly jewelry precision (down to microns). Therefore, this know-how seriously interested doctors.

As a result of the research, doctors have established that the safety of using a laser beam and the ability to control it in depth and diameter of the impact zone is of particular importance in such a delicate area as refractive surgery. And the triumphant march of laser vision correction technology began. It has been proven that excimer laser beam allows you to change the shape of the cornea without destroying it.

For the first time, an excimer laser beam was used to correct myopia by removing the superficial layer of the cornea by Marshall et al in 1986. The operation was called photorefractive keratectomy (PRK).

The shape of the cornea changed under the influence of a laser, which evaporated tissue from the surface of the cornea. High accuracy made it possible to achieve good predictability of the result and a significant reduction in the side effects of vision correction. But for the patient, the period of restoration of the surface layer (2-4 days) was extremely unpleasant, and adaptation ended only after 3-4 weeks. PRK is recognized as the optimal way to correct mild and moderate myopia. The use of this method for myopia and high-degree astigmatism is associated with the risk of residual myopia (up to 10% of cases) and astigmatism, in addition, the development of corneal clouding is possible, which resolves over time, but residual myopia remains.

In 1989 it appeared new technique laser vision correction - Lasik (Lasik). Essentially this is a combination surgical method vision correction ALK with laser vision correction using the PRK technique.

At ALK Two discs were cut from the cornea, the superficial one was subsequently returned to its place, and the inner one was removed. This method required very great skill from the surgeon, in addition, its accuracy was not very high. When performing laser vision correction using the Lasik method, the upper layers of the cornea are also separated and lifted using a special instrument - a microkeratome. The laser then models the exposed surface, and the raised layers are returned to their place.

When correcting vision using the Lasik technique, the corneal incision, unlike radial keratotomy, occurs in a horizontal plane. The flap is quickly and firmly fixed (due to the structural features of the tissue). As a result, there are subsequently no restrictions on physical activity. For certain indications, laser vision correction performed using the Lasik method has no equal.

Long-term observations of patients have shown that the excimer laser does not cause any disorders, since the impact occurs only on one of the refractive media - the cornea, and the depth of impact is strictly limited.

Today, medical centers and clinics in 45 countries use this technology. Over the past 10 years, about 5 million vision corrections using the Lasik technique have been performed worldwide. In the USA and Japan, the procedure for restoring vision using laser vision correction has long gone beyond the confines of specialized clinics. Often small laser correction centers can be seen in the territories of large shopping and entertainment complexes, next to dental and cosmetology offices and beauty salons. The patient undergoes a vision diagnosis, and then, according to the data obtained during the examination, the doctor makes a correction. In addition, the US government, as part of the National Armed Forces Improvement Program, year after year pays for laser vision correction for military personnel of all ranks and branches of the military.

The first refractive surgery to correct myopia was proposed by Barraquer in1949 He proposed removing part of the corneal tissue in its thickness, this operation was called. The corneal tissue was excised with a knife, and subsequently the corneal disc was frozen and turned on a lathe. The operation has not been widely used due to the low accuracy of the results obtained and the risk of developing corneal clouding.

Until recently, the most common operation to eliminate myopia was (“incisions”, RK). The purpose of this operation is to make 4-12 deep (almost through) incisions on the cornea. Due to the formation of scars, the central part of the cornea flattens, the focus moves towards the retina. This technique was widely used until the end of the 1980s, but it gave many complications and had many disadvantages, such as a decrease in the mechanical strength of the cornea (in cases of a blow to the eye, it could burst along the scars, like orange slices), the presence of rough scars on the cornea, insufficient the accuracy of the result obtained, a decrease in the effect over time, the impossibility of correcting high astigmatism, etc.

Thermokeratoplasty has been used to correct farsightedness since the end of the last century. The principle of the operation is to apply point coagulations (cauterizations) to the extreme part of the cornea using a hot tip or a thermal laser. After surgery, pinpoint opacities - scars - form on the periphery of the cornea, and the central part of the cornea becomes steeper. Currently, thermokeratoplasty has limited use due to its unstable and weak refractive effect and strong damaging effect on the cornea.

But all these were operations in which the laser had not yet been used. The first report on the possibility of using excimer lasers to change the refractive power of the cornea was made by Trockel in 1983.

Excimer lasers get their name from a combination of two words: excited - excited, dimer - dimer. An excited dimer is an excited noble gas atom and a halogen atom that form a diatomic gas molecule. The subsequent decay of this molecule results in the emission of a high-energy photon in the ultraviolet range. The principle of the influence of the ultraviolet range (less than 300 nm) on an organic compound, in particular on corneal tissue, is the separation of intermolecular bonds and, as a result, the transfer of part of the tissue from a solid to a gaseous state (). Wherein thermal effect on the fabric (burn) is absent.

For the first time, an excimer laser beam was used to correct myopia by removing the superficial layer of the cornea by Marshall et al in 1986. The operation was called PRK. PRK is recognized as the optimal way to correct low to moderate myopia. The use of this method for myopia and high-degree astigmatism is associated with the risk of residual myopia (up to 10% of cases) and astigmatism, in addition, the development of corneal clouding is possible, which resolves over time, but residual myopia remains.

With the advent of these complications, there was a need to develop a method that would correct myopia and high-degree astigmatism (over 6.0 D). LASIK became such a method (derived from the English abbreviation LASIK - Laser Assisted in situ keratomileusis). The history of LASIK dates back to 1989, when Burrato performed the first keratomileusis surgery using an excimer laser. It was subsequently improved by Pallikaris. Unlike PRK, with LASIK, photoablation is carried out while preserving the surface layer of the cornea, which is capable of regenerating and reducing the effectiveness of PRK. Thus, LASIK can be used to correct high myopia and astigmatism without the risk of developing haze and residual myopia. Every year, the equipment used for operations is improved, and the number of complications also decreases. The keratome model is of no small importance when performing this operation. A keratome is a rather complex instrument used to create a superficial corneal flap containing the regenerating part of the cornea, since until recently the main complications of the operation were problems associated with the microkeratome. The most modern and at the same time successful model is the Chiron Vision Hansatome microkeratome, the main advantage of which is the location of the flap pedicle at the top, which is the most physiological; in addition, the device is highly reliable and at the same time easy to use.