The essence of the disease - a severe disturbance of the refractive power of the optical function in the meridians: horizontal (weak) and vertical (strong). They are perpendicular to each other. When the disease occurs light focus at different points, which does not fall on the retina. Based on this expert establishes disappointing diagnosis.
What it is?
Astigmatism - a violation of the sphericity of the lens and the corneal surface. When the disease breaks the light beam falling on the retina. Projected focus in front and behind the retina. focus violation leads to a view of the nebula. Blur is developing unevenly.
Nebula arises in some areas. A careful analysis of the individual spots can be traced. Ophthalmologists say that the shadow point in the pathology creates a linear image, so distorted perception of surrounding objects. A person with astigmatism sees a circle instead of an oval.
The main reason for astigmatism eye - wrong configuration of the optical system. It appears when uneven curvature of the cornea or irregular shape of the lens. astigmatism disease can occur in congenital uneven pressure of the eyelids, eye socket bone and eye muscles.
If ocular astigmatism has acquired forms, it could provoke the following factors:
- carrying out eye surgeries - in this embodiment, the main cause of astigmatism may be incorrectly suturing the cornea, in which produces an incision, which can lead to a change in its form, namely if very strapped wound edges, when passing sutures or early disposal;
- Different types of injuries or sharp piercing objects, which resulted in corneal scarring or subluxation of the lens;
- corneal opacity due to inflammation;
- keratoconus - corneal pathology that causes thinning, as a result, it acquires a pointed conical shape;
- trauma dental system structure - the wrong structure of the upper jaw and its strong protrusion forward and the lack of a large number of teeth may cause deformation of the walls of the orbit, which in turn will promote astigmatism;
- pterygium - the expansion of the conjunctiva on the cornea, often occurs with prolonged and frequent exposure to the sun.
Often the disease is inherited. In this regard, the presence of astigmatism in one of the parents, the child should be examined by an ophthalmologist as soon as possible.
Astigmatism can be divided into 3 types, which are directly related to the state of farsightedness or nearsightedness:
|short-sighted||meridians struck myopia (singly or together).|
|hyperopic||meridians struck hyperopia (one or both).|
|Mixed||this type of astigmatism and hyperopia is, and myopia.|
All of these species can develop on the background of the following abnormalities:
- Straight or reverse astigmatism (location meridians and their spacing).
- Lens or corneal astigmatism (of them mentioned above).
It is worth noting that with a little astigmatism, people do not notice much deterioration of sight, but Depending on the species may appear in the form of the primary symptoms of a split, dizziness and blur.
Symptoms symptoms of astigmatism may be small, and eventually will be manifested more and more. It is important to detect the disease in time, and take the necessary medical measures - primarily consult an ophthalmologist.
The main symptoms of astigmatism:
- constant eye fatigue;
- irritation of the eyeball;
- blur or distortion of an image;
- difficult to catch the focus (especially while reading);
- visual fatigue;
- difficulties in placing objects near and far objects;
- headaches in the brow part.
It is important to notice blurred vision and timely adjust his glasses, lenses or other recovery methods.
How does astigmatism: photo
The photo below shows how the disease manifests itself in adults and children.
methods of diagnosis
If you suspect that astigmatism specialist conducts a comprehensive survey. Additional methods are distinguished:
- visometry - check visual acuity with special medical tables;
- skiascopy, or shadow test (diagnostic procedure using spherical and cylindrical lenses to determine the refraction degree);
- refractometry (hardware method for more detailed information about refractive eye disease);
- corneal topography (computer procedure for the preparation of a topographic map of the cornea).
To identify the causes that led to the astigmatism used biomicroscopy, ophthalmoscopy and ultrasound study.
treatment of astigmatism
The effectiveness of treatment of astigmatism correction and is defined by its type and degree. For example, the correct astigmatism can be corrected quite easily by using special contact lenses or glasses, while the irregular astigmatism trudnoizlechim and often requires surgical intervention.
For correction and treatment of astigmatism can be used:
- contact lenses;
- replacement of the lens;
- laser correction;
- exercises for the eyes.
Spectacle correction of astigmatism
In astigmatism often prescribe special "complicated" points with special cylindrical lenses. Experts mention that the wearing of "difficult" points in patients with a high degree of astigmatism can cause unpleasant symptoms, such as dizziness, pain in the eyes, eye the discomfort.
Unlike simple points in the recipe on the astigmatic "complicated" points appear data about the cylinder axis and its location. It is important that the selection of points to the patient a thorough diagnosis was conducted.
Because often there are times when a person with a diagnosis of "astigmatism" is necessary several times to change their glasses.
Contact lens with astigmatism
For the treatment of astigmatism contact lenses are chosen according to the same principles as the spectacle lenses. However, it is worth noting that compared to the lens glasses have a number of advantages.
The advantages of contact lenses over conventional glasses include:
- A constant distance from the retina. If they are wearing glasses (spectacles) continually shifted a few millimeters forward or backward, causing the focal length of the lens is also displaced. This leads to a decrease (albeit minor) visual acuity and accommodation tension. When using lenses their distance from the retina is always the same, which ensures a stable correction of astigmatism.
- More effective vision correction. When wearing glasses there is a certain distance between the lens and the cornea (10 - 12 mm), which creates an additional "interference" in the path of light rays. The lens is fixed directly on the cornea and is in close contact with it, forming a single refractive system, which significantly increases the effectiveness of the correction.
- Cosmetic effect. Many people are embarrassed to wear glasses and feel uncomfortable in them. Contact lenses are virtually invisible and do not cause discomfort to the person who wears them, so are the ideal solution for these patients.
For the correction of astigmatism may be used:
- Hard contact lenses. They are made of solid polymer, whereby retain its permanent shape. Moreover, the hard contact lens and trapped between it and the cornea tear fluid to a certain conducive to equalize the cornea, thereby reducing the degree of astigmatism and improves sharpness view.
- Soft contact lenses. They are made of soft materials and can be spherical, cylindrical or spherocylindrical (toric).
It is worth noting that the important issue of the appointment of contact lenses is a way to fix them. If you are using a spherical lens it is not so important, since it has the same refractive power along its entire length. At the same time, using a cylindrical or toric contact lenses is very important that the axis Cylinders are placed exactly perpendicular to the affected meridians, or the desired effect not from them will be.
Excimer laser correction of astigmatism
In recent years, for the treatment of astigmatism (up to ± 3,0 D) is most commonly used excimer laser surgery. Laser correction by the method is hardly LASIK surgery. This procedure is carried out for 10-15 minutes under local anesthesia drip, the laser exposure does not exceed 30-40 seconds, depending on the complexity of the case.
During LASIK vision correction by a special device - microkeratome separated surface layers of thickness 130-150 microns of the cornea, the laser beam opening access to its deeper layers. Then, the laser vaporizes a portion of corneal flap is returned and fixed in place due to collagen's own substance of the cornea. joints are not required overlay, as the restoration of the epithelium along the edge of the flap comes naturally.
After LASIK vision correction method minimum rehabilitation period. Good to see the patient begins after 1-2 hours after the procedure, and the final vision is restored within a week.
Exercising with astigmatism is used in combination with other treatments. Performed a systematic long course. Gymnastic procedures help lead the eye muscles in tone, relieve their stress.
General principles of gymnastics at the non-sphericity of the cornea:
- A set of exercises allows you to warm up and stretch the muscles;
- After performing the charge necessary to keep sight for 10 seconds;
- Peripheral vision leads to a relaxation of the cornea, lens;
- Between exercises need to withstand a break;
- The complex consists of strengthening procedures and relaxing part;
- To improve the visual acuity is recommended that frequent looked from distant objects to neighbors;
- The list of exercises - eye movement up and down, left and right, in a clockwise direction;
- When the charging is necessary to reduce the view to the bridge of the nose;
- Frequent blinking and smooth is also useful.
There are several exercise complexes eye for the correction of visual acuity. Developed whole school gym with astigmatism.
Surgical treatment is to establish the perimeter of the cornea deep cuts, changing its curvature. After surgery recovery period can last for a long time.
Selection regimen depends on what degree of pathology revealed the diagnosis, of the presence of scar tissue and age of the patient.
children, treatment begins with spectacle correction of astigmatism, LASIK safety of this technique makes it possible to use in pediatric patients.
Patients with astigmatism is important to constantly monitor your vision at the doctor, changing glasses and undergo preventive treatments. You should know that the wearing of the entire period of some lenses and glasses are not permissible, as changes occur in the process of aligning the cornea, requiring replacement and corrective therapy.
Ophthalmologist for treatment of astigmatism may issue a special memo painted exercises for the eyes. Exercises regularly carried out to prevent further falling of or in combination with the basic scheme of treatment lead to a marked positive outcome.
Prediction and prevention of astigmatism
At untimely or inadequate treatment of astigmatism may develop sharp decline in visual acuity, amblyopia, strabismus. The criteria for qualitative carrying out the correction of astigmatism is to improve the quality of binocular vision.
Prevention of astigmatism is rational distribution of visual stress, their alternation with special exercises eye and physical activity, prevent injury and inflammation the cornea. For congenital astigmatism necessary to conduct medical examination of children according to age schedule. Prevention of secondary complications require prompt optical correction of astigmatism.