Excimer laser surgery changes the geometry of the cornea. As a result of such an operation, the human optical system becomes more perfect, and the patient no longer needs to use optical correction products (glasses or contact lenses).
It is important to note that during the surgical treatment of ametropia, the refractive power of the retina changes, as a result of which the rays from the image are clearly focused in the macular zone. At the same time, vision improves significantly.
Why is vision reduced?
Refraction refers to the optical power of the entire eye. Refraction is usually expressed in diopters. When this function is impaired, visual acuity decreases, which leads to a decrease in quality of life.
Astigmatism, myopia and farsightedness in all cases are accompanied by a decrease in visual acuity. Any refractive error leads to the fact that the focal point of the rays is not located in the plane of the retina, but in front or behind it. Therefore, such patients require correction of visual function using external optical devices (glasses or contact lenses). This requirement can cause some inconvenience and is sometimes unsafe.
Among diseases accompanied by refractive error, myopia is the most common. According to statistics, one third of all the inhabitants of the Earth suffer from farsightedness. The disease can be diagnosed at any age, but most myopia patients are diagnosed at the age of 8-16 years. In the future, the disease may stabilize or continue to progress. In any case, myopia affects the quality of life, causes discomfort to the patient, and therefore requires careful attention from specialists.
It should be noted that any visual impairment requires mandatory correction. Many people believe that when using glasses to correct vision, visual acuity decreases, but this is not true. On the other hand, if you do not use any correction method, your eyes may stop working, which will certainly lead to amblyopia over time. In this case, even with perfect vision correction, it will not be 100%
Why do you need laser vision correction?
Due to the fact that many people suffer from refractive errors (farsightedness, astigmatism, nearsightedness), specialists are constantly developing new effective methods of treatment. One of the new methods that are very effective for ametropia is the laser restoration of visual function.
Despite the fact that both glasses and contact lenses are widespread, easy to use and affordable, every day several thousand people turn to specialists with a request to perform laser vision correction.
It is quite easy to explain why this happens. First, even the most modern glasses bring some discomfort to their owners. During prolonged wear, pressure occurs on the bridge of the nose and ears, which is sometimes accompanied by pain. Also, glasses are very inconvenient to wear in winter, because with a sudden change in temperature in a warm room, the glasses immediately fog up. In addition, when engaging in active sports, glasses not only cause discomfort, but can be dangerous.
Glasses, like contact lenses, can be forgotten or lost, so the prudent person always has an extra pair to replace them.
If you choose the right contact lens, it will definitely reduce the discomfort. For example, the lenses do not fog, do not put pressure on the bridge of the nose, and are comfortable for active activities. However, when using any lens, even the most modern, the concentration of oxygen in the cells of the cornea decreases. As a result, channels from the base layer begin to grow into the cornea, and dry eye syndrome may also develop over time. Often, irreversible changes in the eye occur 5-10 years after starting to use contact lenses. After this, patients quite often have to switch to glasses or look for other alternatives.
Laser correction for refractive errors helps patients to get rid of contact lenses and glasses forever, so this treatment provides a high standard of living.
It is important to know that not all patients are suitable for ametropia laser treatment. For example, children under the age of 18 cannot undergo laser correction, because the growth of their eyeballs is not yet complete. For this category of patients, glasses and contact lenses are the only possible way to improve visual acuity. In this case, it is important to wear the lenses correctly so as not to cause irreversible changes to the cornea. An ophthalmologist will help you do this if you visit him regularly and monitor the dynamics of vision changes.
Preoperative preparation for laser vision correction
To perform laser vision correction surgery, you must first conduct a comprehensive ophthalmological examination. During the diagnosis, the doctor evaluates the condition of the eyeball as a whole and all its structures separately. Many important parameters are also measured.
The main diagnostic methods include:
- Visometry, which is the measurement of visual acuity;
- Pneumotonometry, necessary to determine the value of intraocular pressure;
- Pachymetry, where the thickness of the cornea is measured;
- Autorefractometry, where the refraction of the eye is determined automatically;
- Echobiometry is necessary to measure eye length;
- Perimetry, that is, determines the boundaries of the field of view;
- Schrimer's test is necessary to assess the amount of tear fluid produced;
- Computer topography analysis of the cornea, which is a modern method to clarify the structure of the cornea;
- Examination of fundus structure after initial maximal mydriasis using drug drops.
After careful preoperative preparation and diagnostics, the doctor can speak with high certainty about the results that the patient can expect after laser correction. This also allows you to avoid the most common complications in the postoperative period.
How is laser vision correction performed?
During the operation, a minimally invasive effect is performed on the corneal material, which leads to a change in the curvature of its surface.
After the doctor corrects the shape of the cornea using an excimer laser, the rays from the image focus on a point located strictly in the plane of the retina. All methods used in modern medicine are very safe, accurate and provide high visual acuity.
The laser vision correction operation itself lasts about 10-15 minutes on average. During the operation, local anesthesia is used, which is done with special eye drops. This allows you to minimize pain, both during and after the procedure. After the operation is completed, the patient is observed in the clinic for about an hour and a half. Then the patient is sent home, having given all the previous recommendations. It is important to note that laser vision correction surgery has almost no effect on the patient's rhythm of life, that is, restrictions in the postoperative period are minimal.
Already at the stage of a full medical examination, the doctor will give all the explanations about the features of the pre-operative and recovery period. To systematize this information, there is a very simple reminder where the patient will find answers to all his questions.
Benefits of excimer laser vision restoration
Vision correction using the excimer laser is a very common procedure that is required in all countries.
Advantages of the method include:
- Reliability of results;
- not painful;
- Speed of execution (no more than a quarter of an hour);
- Security;
- Carry out manipulations on an outpatient basis;
- Various possibilities;
- Short recovery period;
- Predictable and predictable results with high accuracy;
- No cuts or stitches;
- Simplicity and accessibility;
- No additional testing is required;
- High efficiency that lasts a lifetime.
It should be noted that, despite the many possibilities of laser vision correction, this operation does not guarantee the absence of various eye pathologies in the future.
Contraindications for laser vision restoration
Unfortunately, it is not always possible to perform laser correction of visual function. All contraindications for this operation can be divided into two large groups: temporary and permanent. Among the temporary contraindications, the most common is eye (or body as a whole) pathology that can be reversed. After the disease is cured, it is quite possible to do laser correction. Temporary contraindications include:
- Progressive myopia, due to unstable refraction;
- Acute inflammatory changes, both in the eye itself and in other body systems;
- Pregnancy;
- Lactation period;
- Changes in the fundus, including rupture and dystrophic changes;
- Degenerative process in corneal cells.
If there are persistent contraindications, laser vision correction becomes impossible. These include:
- Thin cornea;
- Glaucoma;
- Lens subluxation;
- retinal detachment;
- Cataracts;
- Decompensated diabetes mellitus;
- Previous surgical treatment for retinal detachment.
Interestingly, although there are absolute contraindications for laser vision correction, you can choose an effective alternative treatment method that will help restore vision.
The main difference between laser surgery and other techniques
Laser correction for refractive error includes several types. After reading the name, most patients do not understand the essence of the operation, because abbreviations or designated terms are mainly used. A distinctive feature of REIC and LASIK operations from SuperLASIK is the second stage of the operation, when a femtosecond laser is involved in the process.
The term SuperLASIK, which is used in practice, is not entirely correct, because patients may think that the conventional LASIK technique is somehow inferior to it and inferior. In foreign literature, a more accurate term is used (custom LASIK). In translation, this operation should be called personalized LASIK. This does not mean that traditional LASIK surgery has disadvantages. Only in some special cases it is better to perform SuperLASIK, while in other situations you can limit yourself to a simple LASIK operation. That is why, when choosing a laser vision correction method, an individual approach should be used, which takes into account the preoperative examination data.
An important difference between FemtoLASIK and traditional laser correction is that the operation is completely non-contact. The first stage, where the superficial flap of the cornea is cut with a microkeratome blade, in FemtoLASIK is performed using a femtosecond laser. This technique is relatively new, so sufficient experience has not yet been accumulated to clearly determine its effectiveness and safety.
Some doctors believe that the femtosecond laser is much safer than the microkeratome, but other experts disagree with this statement and prefer the mechanical formation of the flap.
Another new method of laser vision correction is the Smail operation. During this procedure, only a femtosecond laser is used, and the level of surface valve formation from the corneal tissue is absent. In this case, the refractive section is immediately formed in the inner layer of the cornea. The latter is removed through a minimal incision (2-4 mm) in the superficial layer of the cornea using a special instrument. This incision is also made with a femtosecond laser.
It is very important to understand that vision and eyes are one of the most important tools for human interaction with the outside world. Few people can disagree that a person needs points continuously, that is, 365 days a year. That's why it's important to take care of them starting from childhood.