What is astigmatism?
What is Astigmatism? What are the solutions provided by modern medicine for this pathological phenomenon ?!
Normally, light rays that reach the retina are refracted in such a way that the focus is positioned at the center of the retina, or the so-called macula. In this normal position, we can clearly see the image in front of us.
In the case called nearsightedness, the focus is before the retina, and so we can see the objects close to the eye clearly, while there is blur in the vision of distant objects.
In the case called farsightedness, the focus is after the retina. If the foresight is great, the patient suffers from a defect in seeing objects near the eye, and then suffers, at a later stage, from a defect in seeing objects far from the eye.
Astigmatism is a condition of refractive disorder in which a patient needs a cylindrical lens (Cylinder). Astigmatism is caused by varying levels of convexity in different parts of the cornea or lens of the eye. In this case, the light rays collect in two points located in different places in the eye, which would distort the light rays that reach the eye, and lead to blurring of the far and near vision.
Astigmatism is a widespread phenomenon among people. But a good percentage of people with reduced astigmatism do not know at all that they have this condition. Astigmatism is measured according to the "Diopter" units, which is the unit of measurement for refraction in lenses, as is the case with measuring the number of glasses. In fact, the total number found, consists of the correction number, the lens lens number, and the cylindrical axis. As for the method that is used to determine the number in the eye, it is done through an examination called a refraction examination. This ophthalmologist (optometrist) or ophthalmologist will perform this examination, which requires visual equipment.
Astigmatism can be classified according to different degrees: low degree (up to 1 diopter), medium degree (between 1 - 3 diopters) and high degree (more than 3 dioptres).
In addition to the degree, the direction of astigmatism is determined as to whether the structure is uniform or not. It is possible to know whether there is regularity or irregularity through the use of various imaging methods, the most important of which is the imaging of the corneal topography. This imaging allows receiving information related to the hunching of different parts of the cornea, and it is an important means in the suitability of specialists for contact lenses, as it contributes to determining the suitability of a person to perform the removal of glasses by laser rays, and in the diagnosis of various corneal diseases such as keratoconus (keratoconus) Pellucid marginal degeneration).
It is worth noting that in cases of high and irregularity of astigmatism, and in cases where astigmatism increases during a short period, it is important for the ophthalmologist to examine the patient, and in some cases he may recommend a corneal topography examination in order to diagnose or exclude infection with these diseases In the cornea.
How is astigmatism treated?
The conservative method used to treat astigmatism is the use of optical aids, such as glasses or contact lenses, designed to repair this deformation.
Another way to treat astigmatism is to perform various types of surgeries to fix visual distortion:
Laser treatment - In this treatment, the outer surface of the cornea is polished according to the astigmatism (number) the patient suffers from, and according to the required visual axis. The laser treatment is based on the refractive scans and corneal imaging of the patient, which was performed using modern computerized techniques. With this treatment, astigmatism can be repaired with a high degree of accuracy, as long as its structure is uniform.
Astigmatism keratotomy (AK - Astigmatic keratotomy) - This procedure permits the creation of various cracks in the cornea with a diamond knife. In this way, existing astigmatism is reduced (and even removed). This treatment is often performed as part of an additional surgery being performed (for example, in the context of cataract surgery for a patient with astigmatism).
Intraocular lens implantation - this process is called "Faco". In these cases, it is about people between 20-40 years old, who suffer from nearsightedness or farsightedness to a large degree, with or without astigmatism. A small, microscopic industrial lens is inserted into the eye during this surgical procedure. This lens performs the required visual repair. About 2% of people who are tested for their suitability for laser glasses removal are appropriate for a lens implant. There are different types of lenses, as the best quality and safest way to fix nearsightedness is the Artiflex lens, while Artisan is the most effective lens for treating middle to high astigmatism. Other types of lenses used to repair astigmatism include an ICL lens.
For people with cataract, an additional surgical treatment is the use of lenses during surgery. In this surgical procedure, the natural black ophthalmic lens is removed and replaced with an artificial one. Today, this procedure is usually performed by creating a small incision of 1-3 mm in length, during which the natural eye lens is aspirated with a sophisticated ultrasound. Upon completion of the process, an artificial lens is implanted into the eye and the incision is closed without the need to suture. The period of time required for the operation to take place and the recovery period required for recovery after are usually short. Also, implanted lenses are able to fix the number, and they cannot repair astigmatism if any. Thus, a person who suffers from cataract and astigmatism eventually needs to wear glasses