Astigmatism

Astigmatism: It is another type of eye weakness, in which the light rays that reach the eye in parallel form after passing through the cornea and lens of the eye instead of being focused in one focus. Astigmatism is caused by changing the radius of curvature of the cornea at different angles, which means that the power of light refraction is not the same in all parts of the cornea, so the light rays that reach the cornea are not refracted equally in all directions after passing through the cornea, and the eye produces an image with multiple focal points and lines. In this case, a person may not fully recognize the direction of the letters of a line when looking at a vision board, that is, in the same line, he may recognize the direction of the upper and lower letters, but he may not recognize the direction of the left and right letters in the same line. Astigmatism includes different types depending on whether the foci are in front of the retina or behind the retina. Weakness of astigmatism type may be only in the form of astigmatism or it may be combined with degrees of nearsightedness and farsightedness. Therefore, an eye with astigmatism at a fixed and certain distance sees some points of an image clearly and some points of the same image dimly or sees some lines in one direction clear and in another direction.

Weakness of astigmatism is corrected according to its amount and severity by installing cylindrical lenses on the eyeglass frame or using soft toric contact lenses or by using hard lenses or surgical methods. This condition can be completely corrected with glasses, but if the angles of refraction of light are not perpendicular to each other, it is called irregular astigmatism. Usually, this condition cannot be completely corrected with glasses, and if a person wants to have good vision, he must use hard lenses. In the occurrence of astigmatism, only irregularities and disorders of the corneal surface of the eye are involved, and these irregularities and disorders of the corneal surface may be caused by trauma to the cornea, corneal surgical incisions, scar tissue and opacities, corneal surface burns and eyelid tumors. Astigmatism, both regular and irregular, must be corrected because, in addition to not having good vision, when doing things that require precision, such as reading, watching TV, sewing, doing art work, working with computers and mobile phones, driving, and other tasks that require precision vision, people quickly experience dry eyes and headaches in the forehead and back of the head. This situation becomes unbearable for a person sometimes. Therefore, if a person quickly experiences eye fatigue, headache, and lethargy while performing such tasks, he should definitely refer to an optometrist or an ophthalmologist for an eye examination. Sometimes the curvature of the cornea may be more than normal and the cornea may be bent, which is called keratoconus. If the cornea is not too severe, it can be corrected with glasses, and if it is a little more and the person does not have good vision with glasses, it is corrected by using hard lenses, and if the cornea is too thin due to the cornea and the cornea is very severe, even with the use of hard lenses, the person will not be able to see well, so the person will have to perform a cornea transplant surgery.

Eye examinations in astigmatism: as explained, the weakness of astigmatism in the eye, depending on its amount, in addition to causing blurring of vision, causes fatigue, burning, redness, and finally headache when doing tasks that require precision. Therefore, to solve these problems, it should be corrected as soon as possible, especially at the present time and with the advancement of technology, most people will feel more problems due to the continuous use of smartphones (mobile phones, tablets, and touch screens). On the other hand, if the occurrence of astigmatism is under the age of 9 years, if it is not corrected in time, it will cause eye laziness, which is a very, very important issue and should be followed up immediately so as not to cause problems for the child's eye system. Astigmatism is usually fixed most of the time and does not change, but in some cases it may change and if not properly followed up, it may lead to keratoconus. If there is astigmatism in the eyes of children up to the age of 9, it is better to have a complete and accurate examination by an optometrist or ophthalmologist every six months, and adults should have regular examinations at least once a year.

Write your opinion Cancel response