Excimer laser surgery modifies the geometry of the cornea. Thanks to 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 surgical treatment of ametropia, the refractive power of the retina changes, so the image rays are clearly focused in the macular area. At the same time, vision improves significantly.
Why does vision decrease?
Refraction refers to the optical power of the entire eye. Refraction is usually expressed in diopters. When this function is impaired, visual acuity decreases, leading to a reduction in quality of life.
Astigmatism, myopia and hyperopia are in all cases accompanied by a reduction in visual acuity. Any refractive error leads to the fact that the focus of the rays is not located in the plane of the retina, but in front or behind it. Therefore, these patients require correction of visual function using external optical devices (glasses or contact lenses). This necessity can cause certain inconveniences and is sometimes dangerous.
Among the diseases accompanied by refractive errors, myopia is the most common. According to statistics, a third of all inhabitants of the Earth suffer from myopia. This disease can be diagnosed at any age, but most often myopic patients are diagnosed between the ages of 8 and 16. In the future, the disease may stabilize or continue to progress. In any case, myopia affects the quality of life, causing discomfort for the patient, and therefore requires special attention from specialists.
It should be noted that any visual impairment requires mandatory correction. Many people think that when using glasses to correct vision, visual acuity decreases, but this is not true. On the contrary, if you do not use any correction method, your eyes may stop working, which will definitely lead to amblyopia over time. In this case, even with perfect visual correction, it will not be 100%
Why do you need laser vision correction?
Since many people suffer from refractive errors (hyperopia, astigmatism, myopia), specialists are constantly developing new effective treatment methods. One of the new, very effective methods against ametropia is laser restoration of visual function.
Despite the fact that glasses and contact lenses are widespread, easy to use and affordable, several thousand people every day turn to specialists to carry out laser vision correction.
It's pretty simple to explain why this happens. Firstly, even the most modern glasses bring some discomfort to their owner. During prolonged wear, pressure occurs on the bridge of the nose and ears, sometimes accompanied by pain. It is also very inconvenient to wear glasses in winter, because with a sharp change in temperature in a warm room, the glasses immediately fog up. In addition, when playing active sports, glasses not only cause discomfort, but can also be dangerous.
Glasses, like contact lenses, can be forgotten or lost, so prudent people always have an extra pair to replace them.
If you choose the right contact lenses, they will undoubtedly cause less discomfort. For example, the lenses do not fog up, do not put pressure on the bridge of the nose and are comfortable for active activities. However, when using lenses, even the most modern ones, the concentration of oxygen in the corneal cells decreases. As a result, vessels from the underlying layers begin to grow into the cornea and dry eye syndrome may also develop over time. Most of the time, irreversible changes in the eye occur 5 to 10 years after starting contact lens use. After that, patients often have to wear glasses or look for another alternative.
Laser correction of refractive errors helps the patient to permanently give up contact lenses and glasses, therefore this treatment provides a high standard of living.
It is important to know that not all patients are suitable for laser ametropia treatment. For example, children under 18 cannot undergo laser correction, because the growth of their eyeball has not yet been completed. 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 have a complete eye exam. When making a diagnosis, the doctor separately assesses the condition of the eyeball as a whole and all its structures. Many important parameters are also measured.
The main diagnostic methods include:
- Visometry, i. e. measurement of visual acuity;
- Pneumotonometry, necessary to determine the value of intraocular pressure;
- Pachymetry, during which the thickness of the cornea is measured;
- Autorefractometry, in which the refraction of the eye is determined automatically;
- Echobiometry required to measure eye length;
- Perimetry, i. e. determining the limits of the field of vision;
- The Schrimer test is necessary to assess the amount of tear fluid produced;
- Computer topographic analysis of the cornea, which is a modern method for clarifying the structure of the cornea;
- Examination of fundus structures after preliminary maximum mydriasis using medicinal drops.
After careful preoperative preparation and diagnosis, the doctor can speak with great 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 carried out?
During the operation, a minimally invasive effect is exerted on the substance of the cornea, 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 image rays converge at 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 on average about 10 to 15 minutes. During the operation, local anesthesia is used, carried out with special eye drops. This allows you to minimize pain, during and after the procedure. Once the operation is completed, the patient is observed in the clinic for approximately one and a half hours. Then the patient is sent home after giving all the recommendations. It is important to note that laser vision correction surgery has practically no effect on the patient's pace of life, that is, postoperative restrictions are minimal.
Already at the stage of a comprehensive medical examination, the doctor will give all explanations about the features of the preoperative and recovery period. To systematize this information, there are very practical reminders in which the patient will find answers to all their questions.
Benefits of excimer laser vision restoration
Vision correction using an excimer laser is a very common and demanded procedure in all countries.
The advantages of the method include:
- Reliability of results;
- Painless;
- Speed of execution (no more than a quarter of an hour);
- Security;
- Carry out outpatient manipulations;
- Wide range of possibilities;
- Short recovery period;
- Predictable and predictable result with high accuracy;
- No cuts or seams;
- Simplicity and accessibility;
- No additional testing is necessary;
- High efficiency that lasts a lifetime.
It should be noted that, despite the wide possibilities of laser vision correction, this operation does not guarantee the absence of various eye pathologies in the future.
Contraindications to laser vision restoration
Unfortunately, it is not always possible to perform laser correction of visual function. All contraindications to this operation can be divided into two large groups: temporary and permanent. Among the temporary contraindications, the most common are reversible pathologies of the eye (or the body as a whole). Once these diseases are cured, it is quite possible to carry out laser correction. Temporary contraindications include:
- Progressive myopia, since the refraction is not stable;
- Acute inflammatory changes, both in the eye itself and in other body systems;
- Pregnancy;
- Lactation period;
- Fundus changes, including ruptures and dystrophic changes;
- Degenerative processes in corneal cells.
If there are constant contraindications, laser vision correction becomes impossible. These include:
- Thin cornea;
- Glaucoma;
- Lens subluxation;
- Retinal detachment;
- Cataract;
- Decompensated diabetes mellitus;
- Previous surgical treatment for retinal detachment.
Interestingly, even if there are absolute contraindications to laser vision correction, you can choose an effective alternative treatment method that will help restore vision.
The main differences between laser surgery and other techniques
Laser correction of refractive errors includes several types. After reading the name, most patients do not understand the essence of the operation, since abbreviations or established 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, used in practice, is not entirely correct, because patients may think that the conventional LASIK technique is somehow inferior and inferior to it. In foreign literature, a more correct term is used (custom LASIK). In translation, this operation should be called personalized LASIK. This does not mean that traditional LASIK surgery has disadvantages. It's just that 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 method of laser vision correction, an individual approach should be used, which takes into account the data of the preoperative examination.
An important difference between FemtoLASIK and traditional laser correction is that the operation is completely contactless. The first step, in which the superficial corneal flap is cut with a microkeratome blade, in FemtoLASIK is performed using a femtosecond laser. This technique is relatively new and therefore sufficient experience has not yet been accumulated to clearly determine its effectiveness and safety.
A number of doctors believe that the femtosecond laser is much safer than a microkeratome, but other specialists disagree with this statement and prefer mechanical flap formation.
Another new method of laser vision correction is the Smail operation. During this procedure, only a femtosecond laser is used and the step of forming a superficial valve from the corneal tissue is absent. In this case, a refractive section is immediately formed in the deep layers of the cornea. The latter is removed through a minimal incision (2 to 4 mm) in the superficial layers 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 deny that a person needs eyes constantly, that is, 365 days a year. This is why it is so important to take care of it from a young age.