Astigmatism, translated from Latin, means “lack of a focal point.” Astigmatism occurs due to an irregular (non-spherical) shape of the cornea (less commonly, the lens). In a normal state, the cornea and lens of a healthy eye have a smooth spherical surface. With astigmatism, their sphericity is disrupted. They have different curvatures in different directions. Accordingly, with astigmatism, different refractive powers are present in different meridians of the corneal surface, and the image of an object passing through such a cornea is distorted.
In simple terms, astigmatism is a condition that occurs because the lens or cornea is elongated into an elliptical shape, although it should be round in a healthy state. Because of this, light is refracted incorrectly and does not focus in the center of the retina. The image is blurred.
Some parts of the image may focus on the retina, while others may focus behind or in front of it (there are also more complex cases). As a result, instead of a normal image, a person sees a distorted image in which some lines are clear and others are blurred. You can get an idea of this by looking at your distorted reflection in an oval teaspoon. A similar distorted image is formed when astigmatism occurs on the retina of the eye.
Specialists distinguish between corneal and crystalline astigmatism. However, corneal astigmatism has a greater impact on vision than crystalline astigmatism, as the cornea has greater refractive power. The difference in refraction between the strongest and weakest meridians characterizes the degree of astigmatism in diopters. The direction of the meridians will characterize the axis of astigmatism, expressed in degrees.

Perfect shapes are rare in nature. Every rose petal and every oak leaf differs from the others in its shape. This is because they have a unique combination of genes. The same can be said about the refractive surfaces of the eye. People are born with individual characteristics of the cornea and lens configuration, which are inherited. There are as many characteristics of the optical properties of the eye as there are people. That is why defocusing is considered a fairly common disorder of the refractive system of the eye. According to statistics from the Ministry of Health, astigmatism occurs in adults in the following proportions:

• 0.5 D and above — 11.4-67.97%,
• 1.0 D and above — 15.6-22.5%,
• 2.0 D and above — 4.2-5.4%,
• 3.0 D and above — 1.6%.

Corneal astigmatism, when the cornea is not spherical but ellipsoidal in shape, is considered to be more common. As a result, the refractive power of the cornea varies when measured at different meridians of the eye.
Astigmatism can develop over the course of a lifetime due to uneven growth of the eyeball. Astigmatism can be caused by trauma, corneal disease, lens subluxation, previous surgery, or age-related changes.

The main symptom of astigmatism is blurred vision when a person tries to see objects both near and far. When reading, people with astigmatism often confuse similar letters that differ in small details: “F” and “P”, ‘R’ and “P”. In the early stages of this disorder, blurred vision worsens at night and at dusk. Distortion, double vision, and blurred images occur as a result of light rays splitting and forming a complex three-dimensional structure, focusing at several points.
In myopic astigmatism, several focal points may be located in front of the retina. Either part of the image is projected onto the retina, while the other part does not reach it.
Hyperopic astigmatism is characterized by the location of focal points behind the inner membrane of the eye. In complex cases, the focal points may be located both on the retina and behind it.
In addition to reduced vision, symptoms of astigmatism include headaches, rapid fatigue when working on a computer, hypertonicity of the facial muscles, increased lacrimation, and the need to squint to see the small details of an object.

Modern computerized ophthalmic devices make it fairly easy to diagnose astigmatism at any stage of development. A whole range of tests are used for this purpose. For example, aberrometry, ophthalmoscopy, keratometry, keratotopography, and others.
The doctor prescribes the relevant set of tests depending on individual indications. At the Excimer clinic, each patient can undergo a comprehensive diagnosis of the visual system to obtain comprehensive information about the health of their eyes.
As a rule, the examination of the degree of astigmatism begins with standard methods — visometry (determination of visual acuity) and ophthalmoscopy. Using the SC-1600 NIDEK sign projector, the doctor identifies various visual characteristics of the patient — separately for each eye.
Aberrometry can be performed as part of a comprehensive diagnosis or specifically to clarify data when making a diagnosis. Aberrations are any distortions in the optics of the eye. This method is based on wavefront technology and is 20 times more accurate than other diagnostic methods in detecting refractive errors, including astigmatism.
Keratometry, which measures the radius of curvature of the corneal surface, is considered an essential method for diagnosing astigmatism. The Tonoref II NIDEK expert-class autorefractometer is part of the diagnostic equipment at the Excimer Clinic. It measures objective refractive errors, the radius of curvature of the cornea, intraocular pressure, accommodation amplitude, and other parameters in a matter of seconds.
For an even more detailed examination, especially before surgical treatment, keratotopography is performed. The Excimer Clinic is equipped with the Sirius multifunctional corneal topography system, which allows scanning of the cornea and the anterior chamber of the eye. As a result, the doctor receives detailed 3D analysis data for 25 sections of the cornea. For the patient, this examination is non-contact, painless, and takes only a few minutes. The only requirement is that the patient remain still during the examination and be able to fix their gaze on a single point for 25-30 seconds.

If a vision focus disorder is detected in time and an ophthalmologist prescribes the correct vision correction, the pathology usually does not progress.
To prevent astigmatism, especially in children, it is important to follow a number of measures:

• ensure that there is sufficient lighting when working on a computer;
• take regular breaks from reading from a screen to reduce eye strain;
• a balanced diet is also beneficial for vision: include foods containing vitamins A, C, E, B6, and B12 in your diet.

The best prevention for astigmatism is regular checkups with an ophthalmologist — at least once a year.

Experts distinguish three degrees of astigmatism:

• mild astigmatism – up to 3 D;
• moderate astigmatism – from 3 to 6 D;
• high astigmatism – above 6 D.

The symptoms of mild astigmatism are often virtually imperceptible, and a person with this type of refractive error may only learn about their diagnosis during an examination by an ophthalmologist.
With moderate astigmatism, vision impairment becomes noticeable—the higher the number of diopters, the more blurred the image will be. Another unpleasant symptom appears: the image becomes distorted, straight lines begin to curve, and the outlines of objects “float.”
In addition to vision impairment, high astigmatism is characterized by an increase in symptoms associated with constant eye strain. Dizziness, eye pain, and headaches, which are also present to some extent in milder forms of astigmatism, can cause serious discomfort for people with high astigmatism.
To understand how a person with astigmatism sees, just imagine that the world suddenly became as if you were looking at it through a crooked mirror. Lines break, become blurred and unclear.

According to the nature of its occurrence, astigmatism is divided into congenital and acquired.

• Congenital astigmatism—up to 0.5 D—occurs in most children and is considered "functional," meaning it does not affect visual acuity or the development of binocular vision. However, astigmatism exceeding 1 D or more significantly reduces vision and requires treatment with corrective eyeglasses.
• Acquired astigmatism appears as a result of severe cicatricial changes on the cornea following trauma, injury, or eye surgery.

Depending on the refractive error associated with astigmatism, the following types of this visual impairment are distinguished:

• simple hypermetropic or simple myopic astigmatism – a combination of farsightedness or nearsightedness in one meridian of the eyeball and normal refraction in the other;
• complex hypermetropic or complex myopic astigmatism – a combination of farsightedness or nearsightedness of varying degrees in the main meridians of the eye;
• mixed astigmatism is a combination of farsightedness in one meridian and nearsightedness in the other.

In most cases, this aberration does not affect the course of pregnancy or the choice of delivery method. Conversely, astigmatism does not worsen during pregnancy. However, the decision on whether a woman with astigmatism can give birth naturally is made by the attending ophthalmologist and obstetrician-gynecologist. A cesarean section is preferable in cases where the pregnant woman has complications with pronounced degenerative changes in the retina of the eyes.cc

Physical activity is recommended for all people with astigmatism. There are no contraindications based on age or the severity of the refractive error. Another issue is that some sports require sharp vision and high precision. Examples include biathlon, archery, golf, soccer, hockey, and other team sports. Athletes are also required to have increased reaction speed, coordination of movements, and orientation in the terrain. With astigmatism, it is more difficult to develop these skills. The solution may be contact lenses that correctly take into account the degree of refractive error, as well as laser vision correction.

A high degree of astigmatism may be grounds for a conscript not being allowed to enter military service. In this case, the young man is assigned category G or D (temporarily or permanently unfit for service).
A moderate degree of astigmatism from 4 to 6 D is usually grounds for assigning category B, i.e., exemption from conscription into the army in peacetime. However, the person will be conscripted in the event of general mobilization.
A mild degree of astigmatism up to 4 D is not considered a restriction for conscription into military service.

Today, there are three ways to correct astigmatism: glasses, contact lenses, and excimer laser correction.

For astigmatism, special “complex” glasses with special cylindrical lenses are most often prescribed. Experts mention that wearing “complex” glasses in patients with a high degree of astigmatism can cause unpleasant symptoms, such as dizziness, eye strain, and visual discomfort. Unlike simple glasses, the prescription for astigmatic “complex” glasses includes information about the cylinder and its axis. It is very important that the patient undergoes a thorough diagnosis before selecting glasses. This is because there are often cases when a person diagnosed with astigmatism has to change their glasses several times.
With astigmatism, wearing glasses is not only possible, but necessary. Without correction, astigmatism can progress and vision can deteriorate.
It is important to understand that glasses do not cure astigmatism, but only compensate for it. When glasses are removed, the person will again see distorted curved lines. Astigmatism can only be eliminated with laser vision correction.

When discussing the correction of astigmatism with contact lenses, it is important to note that until recently, astigmatism could only be corrected with hard contact lenses. This type of lens was not only uncomfortable to wear, but also had a negative effect on the cornea. However, medicine does not stand still, and today special toric contact lenses are used to correct astigmatism.
Special astigmatic lenses differ from conventional lenses in that three parameters are important for correct selection: diopter power, cylinder power, and cylinder axis. Toric lenses are designed specifically to correct vision problems associated with astigmatism, while conventional lenses do not fully compensate for them.
Patients with mild astigmatism (0.5-0.75 diopters) may be prescribed regular (non-toric) contact lenses. If astigmatism exceeds 0.75 diopters, astigmatic lenses are indicated.

In recent years, excimer laser correction has been the most common treatment for astigmatism (up to ±3.0 D). LASIK laser correction can hardly be called an operation. The procedure takes 10–15 minutes under local anaesthesia, with the laser exposure lasting no more than 30–40 seconds, depending on the complexity of the case.
During LASIK vision correction, a special device called a microkeratome is used to separate the surface layers of the cornea, which are 130-150 microns thick, allowing the laser beam to access the deeper layers. The laser then vaporizes part of the cornea, and the flap is returned to its place and fixed in place by collagen, a substance found in the cornea itself. No sutures are required, as the epithelium at the edge of the flap heals naturally. The rehabilitation period after LASIK vision correction is minimal. The patient begins to see well within 1-2 hours after the procedure, and vision is fully restored within a week.
During consultations with an ophthalmologist, many people ask whether mild astigmatism needs to be corrected. Mild astigmatism does not exceed 1 diopter and does not necessarily need to be corrected. However, if even mild astigmatism affects the quality of vision and causes discomfort, it is important to correct it.

What should you avoid doing if you have astigmatism?
You can participate in sports if you have astigmatism, but you should avoid lifting heavy weights, sudden movements, and intense muscle strain (for example, when weightlifting or working out at the gym). This can negatively affect intraocular pressure. If you have severe astigmatism, it's not a good idea to play team sports because of problems with spatial orientation.