Excimer laser surgery changes the geometry of the cornea. As a result of such an operation, a person's optical system becomes more perfect, and the patient no longer needs to use optical correction products (glasses or contact lenses).
It should be noted that during the surgical treatment of ametropia, the refractive power of the retina changes, as a result, the rays from the image are clearly focused in the macular zone. 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, which leads to a decrease in the quality of life.
In all cases, astigmatism, myopia and farsightedness are accompanied by a decrease in visual acuity. Any refractive error causes the focal point of the rays to be in front of or behind the retina, rather than in the plane of the retina. Therefore, such patients require the correction of visual function using external optical devices (glasses or contact lenses). This need can cause some discomfort and is sometimes dangerous.
Among diseases accompanied by refractive error, myopia is the most common. According to statistics, one third of all inhabitants of the Earth suffer from myopia. This disease can be diagnosed at any age, but in most cases, patients with myopia 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 patient's quality of life, which causes anxiety, and therefore requires serious attention from specialists.
It should be noted that any visual impairment requires mandatory correction. Many people believe that visual acuity decreases when using glasses to correct vision, but this is not true. On the contrary, if you do not use any correction method, your eyes may stop working, which will 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?
Since many people suffer from refractive errors (farsightedness, astigmatism, myopia), specialists are constantly developing new methods of effective treatment. One of the new highly effective methods for ametropia is laser vision restoration.
Despite the fact that both glasses and contact lenses are widely available, easy to use and affordable, several thousand people turn to specialists for laser vision correction every day.
It is quite simple to explain why this happens. First, even the most modern glasses bring some discomfort to the owner. During a long stay, pressure occurs in the bridge of the nose and ears, which is sometimes accompanied by pain. It is also very inconvenient to wear glasses in winter, because the glasses immediately fog up with a sharp change in temperature in a warm room. In addition, when doing active sports, glasses not only cause discomfort, but can also be dangerous.
Glasses, like contact lenses, can be forgotten or lost, so careful people always have an extra pair to replace them.
If you choose the right contact lenses, they will certainly cause less discomfort. For example, lenses do not fog, do not put pressure on the bridge of the nose and are comfortable for active activities. However, when using any lenses, even the most modern ones, the concentration of oxygen in the corneal cells decreases. As a result, the vessels from the lower layers begin to grow in the cornea, and dry eye syndrome may develop over time. In most cases, irreversible changes in the eye occur 5-10 years after starting to use contact lenses. After that, patients often have to switch to glasses or look for another alternative.
Laser correction of refractive error helps the patient to give up contact lenses and glasses forever, so this treatment ensures 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 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 lenses correctly so as not to cause irreversible changes in the cornea. An ophthalmologist will help you do this if you visit regularly and monitor the dynamics of vision changes.
Preoperative preparation for laser vision correction
To perform laser vision correction surgery, you must first undergo a comprehensive ophthalmological examination. During the 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, the measurement of visual acuity;
- Pneumotonometry necessary to determine the value of intraocular pressure;
- pachymetry, which measures the thickness of the cornea;
- Autorefractometry, where the refraction of the eye is determined automatically;
- Ecobiometrics needed to measure eye length;
- Perimetry, that is, determining the boundaries of the field of view;
- Schrimer's test is needed to assess the amount of tear fluid produced;
- computer topographic analysis of the cornea, a modern method for clarifying the structure of the cornea;
- Examination of fundus structures after primary maximum mydriasis using drug drops.
After careful preoperative preparation and diagnosis, the doctor can speak with high confidence about what results 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 substance of the cornea, which causes 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 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 about 10-15 minutes on average. Local anesthesia with special eye drops is used during the operation. This allows you to minimize pain both during and after the procedure. After the operation, the patient is observed in the clinic for about an hour and a half. Then the patient is sent home, having given all the recommendations previously. It should be noted that the laser vision correction operation has practically no effect on the patient's life rhythm, which means that restrictions in the postoperative period are minimal.
Already at the stage of a full medical examination, the doctor will give all the explanations regarding the features of the pre-operative and recovery period. To systematize this information, there are very convenient reminders that will answer all the patient's questions.
Benefits of excimer laser vision restoration
Vision correction using excimer laser is a very common procedure required in all countries.
The advantages of the method include:
- Validity of results;
- painless;
- Execution speed (not more than a quarter of an hour);
- Security;
- Conducting manipulations in ambulatory conditions;
- Wide possibilities;
- Short recovery time;
- Predictable and predictable result with high accuracy;
- no cuts and seams;
- Simplicity and accessibility;
- No additional tests are needed;
- 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, laser vision correction is not always possible. All contraindications of this operation can be divided into two large groups: temporary and permanent. The most common temporary contraindications are eye pathologies (or the body as a whole). After these diseases are cured, it is quite possible to do laser correction. Temporary contraindications include:
- Progressive myopia, because 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 tears and dystrophic changes;
- Degenerative processes in corneal cells.
If there are permanent contraindications, laser vision correction becomes impossible. These include:
- thin cornea;
- glaucoma;
- Subluxation of the lens;
- Retinal detachment;
- cataract;
- decompensated diabetes mellitus;
- Previous surgical treatment for retinal detachment.
Interestingly, even if there are absolute contraindications for laser vision correction, you can choose an effective alternative treatment method that will help restore vision.
The main differences between laser surgery and other methods
Laser correction of refractive error includes several types. After reading the name, most patients do not understand the essence of the operation, because mostly abbreviations or defined terms are used. The distinguishing feature of REIC and LASIK surgeries from SuperLASIK is the second stage of the surgery, where a femtosecond laser is involved in the process.
The term SuperLASIK used in practice is not entirely correct, as patients may think that the traditional LASIK technique is somehow inferior to it and inferior. In foreign literature, a more correct term is used (special LASIK). In translation, this operation should be called personalized LASIK. This is not to say that traditional LASIK surgery has disadvantages. It's just that in some special cases it is preferable to perform SuperLASIK, while in other cases you can limit yourself to simple LASIK surgery. 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. In FemtoLASIK, the first stage, in which the superficial flap of the cornea is cut with a microkeratome blade, is performed with a femtosecond laser. This technique is quite new, so not enough experience has yet been gathered to clearly determine its effectiveness and safety.
A number of doctors believe that the femtosecond laser is much safer than the microkeratome, but other experts disagree 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 there is no stage of forming a surface flap from the corneal tissue. At this time, a refractive section is immediately formed in the deep layers of the cornea. The latter is removed with a minimal incision (2-4 mm) in the superficial layers of the cornea using a special tool. 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 means of human interaction with the outside world. Few people can agree that a person needs eyes constantly, that is, 365 days a year. Therefore, it is very important to take care of them from an early age.