Excimer laser surgery changes the geometry of the cornea. As a result of this 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, causing the image rays to be clearly focused on the macular zone. At the same time, vision becomes significantly better.
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, which leads to a decrease in quality of life.
Astigmatism, myopia and hyperopia 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 need can cause some inconvenience and is sometimes unsafe.
Among the diseases accompanied by refractive error, 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 myopia patients are diagnosed between 8 and 16 years of age. In the future, the disease may stabilize or continue to progress. In any case, myopia affects the quality of life, causing discomfort to the patient and, therefore, requires a lot of 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 contrary, 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 visual 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, myopia), experts are constantly developing new effective treatment methods. One of the new highly effective methods for ametropia is laser restoration of visual function.
Despite the fact that 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 very simple to explain why this happens. Firstly, even the most modern glasses bring some discomfort to their owner. During prolonged use, pressure occurs on the bridge of the nose and ears, which is sometimes accompanied by pain. It is also very inconvenient to wear glasses in winter, since with a sharp change in temperature in a hot environment, the glasses immediately fog up. Furthermore, when playing active sports, glasses not only cause discomfort, but can 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 any lens, even the most modern ones, the oxygen concentration 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. Mostly, irreversible changes in the eye occur 5 to 10 years after starting to wear contact lenses. After that, patients often need to switch to glasses or look for another alternative.
Laser correction of refractive error helps the patient to abandon contact lenses and glasses forever, therefore this treatment provides a high standard of living.
It is important to know that not all patients are suitable for laser treatment of ametropia. For example, children under 18 cannot have laser correction, as the growth of the eyeball 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 use the lenses correctly to avoid causing irreversible changes to the cornea. An ophthalmologist will help you do this if you visit him regularly and monitor the dynamics of changes in vision.
Preoperative preparation for laser vision correction
To have laser vision correction surgery, you must first have a comprehensive eye exam. During diagnosis, the doctor assesses 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, that is, 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;
- Ecobiometry necessary to measure eye length;
- Perimetry, that is, determining the limits of the field of vision;
- The Schrimer test is necessary to evaluate the amount of tear fluid produced;
- Computational topographic analysis of the cornea, which is a modern method for clarifying the structure of the cornea;
- Examination of fundus structures after preliminary mydriasis maximus with medicinal drops.
After careful pre-operative preparation and diagnosis, the doctor can speak with high certainty about what results the patient can expect after laser correction. This also allows you to avoid the most common post-operative complications.
How is laser vision correction performed?
During the operation, a minimally invasive effect is carried out on the substance of the cornea, which leads to a change in the curvature of its surface.
After the doctor has corrected the shape of the cornea using an excimer laser, the image rays converge to 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 lasts on average about 10 to 15 minutes. During the operation, local anesthesia is used, which is carried out using special eye drops. This allows you to minimize pain, both during the procedure and after it. After the operation is complete, the patient is observed in the clinic for about an hour and a half. Afterwards, the patient is sent home, having previously given all the recommendations. It is important to highlight that laser vision correction surgery has practically no effect on the patient's rhythm of life, that is, restrictions in the postoperative period are minimal.
During the complete medical examination, the doctor will provide full explanations about the characteristics of the preoperative period and the recovery period. To systematize this information, there are very convenient reminders in which the patient will find answers to all his questions.
Benefits of vision restoration with excimer laser
Vision correction with an excimer laser is a very common and sought-after procedure in all countries.
The advantages of the method include:
- Reliability of results;
- Painless;
- Execution speed (no more than a quarter of an hour);
- Security;
- Carrying out manipulations on an outpatient basis;
- Wide range of possibilities;
- Short recovery period;
- Predictable and predictable result with high precision;
- No cuts or seams;
- Simplicity and accessibility;
- No additional tests are required;
- 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 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 are reversible eye (or body as a whole) pathologies. After these diseases are cured, it is quite possible to carry out laser correction. Temporary contraindications include:
- Progressive myopia, as the refraction is not stable;
- Acute inflammatory changes, both in the eye itself and in other body systems;
- Pregnancy;
- Lactation period;
- Changes in the fundus, 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 for refractive errors includes several types. After reading the name, most patients do not understand the essence of the operation, since mainly abbreviations or established terms are used. A distinctive feature of SuperLASIK REIC and LASIK operations 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, as patients may think that the conventional LASIK technique is somehow inferior to it and is inferior. In foreign literature, a more correct term (custom LASIK) is used. In translation, this operation should be called custom LASIK. This does not mean that traditional LASIK surgery has disadvantages. It turns out that in some special cases it is preferable to perform SuperLASIK, while in other situations you can limit yourself to a simple LASIK operation. Therefore, when choosing a method of laser vision correction, an individual approach should be used, taking into account the data of the preoperative examination.
An important difference between FemtoLASIK and traditional laser correction is that the operation is completely non-contact. The first step, in which the superficial corneal flap is cut with a microkeratome blade, in FemtoLASIK is performed with a femtosecond laser. This technique is quite new, so not enough experience has yet been accumulated to clearly determine its effectiveness and safety.
Several doctors believe that the femtosecond laser is much safer than the microkeratome, but other experts do not agree 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 surface valve from the corneal tissue is absent. In this case, a refractive section is formed immediately in the deep layers of the cornea. The latter is removed through a minimal incision (2-4 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 disagree that a person needs eyes constantly, that is, 365 days a year. That's why it's so important to take care of them from an early age.