Today's health information is 'causes and treatment and correction of astigmatism'.
Astigmatism is a refractive error in the eye in which light entering the eye is refracted by the cornea and fails to focus at one point, but has two or more focal points. As the type of astigmatism is accompanied by astigmatism, it is divided into complex myopia, simple myopic astigmatism, mixed astigmatism, simple hyperopic astigmatism, and complex hyperopic astigmatism.
Causes of Astigmatism.
The exact cause of astigmatism is still unknown. However, if the parents have astigmatism, the child is more likely to develop astigmatism, so genetic factors are thought to be related. Astigmatism can also be caused by ptosis, ptosis, the eyelids pressing against the eye, or the eyebrows touching the eyeball.
Astigmatism may also develop after an eye disease, such as pterygium, or after eye surgery.
Symptoms of Astigmatism.
The most common symptom of astigmatism is that objects appear blurry and not clear. Unlike with nearsightedness, both distant and near objects cannot be seen clearly.
Mild hyperopic astigmatism may have no symptoms, and in severe cases of astigmatism, eye fatigue occurs due to the accommodation phenomenon (contraction of the ciliary muscle of the eye to see close objects better). Also, if you squint your eyes, it will look a little clearer, so you may develop a habit of squinting your eyes.
In rare cases, severe astigmatism may complain of double vision even when looking at objects with one eye. However, even if you have astigmatism, you may not be aware of it until you enter school or learn to read, so pediatric ophthalmologists recommend that you have your eyesight checked at around 3 years of age.
Eye refractive errors can be broadly divided into hyperopia, myopia, and astigmatism. Some people with severe astigmatism have few symptoms, while others have mild astigmatism but have significant symptoms.
There are also people who have the same degree of astigmatism and have no symptoms at all, while others are very uncomfortable.
Diagnosis of Astigmatism.
Astigmatism is diagnosed by performing a refractive test to measure the degree of refractive error. Farsightedness, myopia, and astigmatism are called refractive errors. The degree of astigmatism is diagnosed through corneal topography, which measures the high degree of cornea and expresses it in the same way as contour lines on a map.
Treatment and correction of astigmatism.
glasses.
The most common method is glasses. Since astigmatism rarely exists alone, glasses that correct for nearsightedness or farsightedness are worn together. In cases where astigmatism is not severe, astigmatism correction is omitted and only myopia or farsightedness correction is performed in some cases. Unlike myopia and farsightedness, astigmatism can cause problems when the values measured through refraction are applied to glasses as they are.
In particular, if you have previously worn non-astigmatism glasses (or did not wear glasses) and then wear glasses that correct astigmatism, sudden increase in astigmatism, different axes of astigmatism in both eyes, and astigmatism axes If it is tilted, or if the astigmatism axis is different from the previous glasses, you may feel dizziness due to distortion of the image (or the difference) caused by the astigmatism glasses.
While young children can easily overcome these initial discomforts, the older they get, the more difficult it is to adapt to these changes, so a compromise has to be found.
contact lenses.
If it is difficult to wear glasses (in case of occupation or considering appearance) or if it is difficult to correct vision sufficiently with glasses due to dizziness, contact lenses are used. Contact lenses are broadly divided into soft contact lenses and oxygen-permeable contact lenses.
Since general soft contact lenses do not have an astigmatism correction function, mild astigmatism has no effect. In this case, you should consider soft contact lenses for astigmatism correction and always have them in a certain direction.
As such, there are methods such as attaching a prism at the bottom or making the design unique, but nonetheless, there is a disadvantage that the eyesight may be unstable if there is a slight rotation. However, severe astigmatism of more than 2.0~2.5 diopters is difficult to correct even with soft contact lenses for astigmatism correction.
Oxygen-permeable contact lenses can correct severe astigmatism, which is difficult to correct even with soft contact lenses for astigmatism, and are the most used contact lenses for severe astigmatism. Astigmatism can be corrected with spherical contact lenses when the astigmatism is small, but astigmatism is usually severe, often using aspherical contact lenses.
refractive surgery.
Recently, refractive surgery such as LASIK and LASEK has been very developed, and it can correct not only farsightedness and myopia, but also the accompanying astigmatism. In case of high myopia, which is difficult to correct myopia such as LASIK or LASEK, intraocular lens implantation can be an alternative.
In the case of intraocular lens implantation for astigmatism correction, if rotation occurs in front of the eyes, the effect of astigmatism correction may decrease, and such complications have been reported.
surgical treatment.
To treat astigmatism, corneal resection, limbal incision, and plastic ring insertion are being performed. Since corneal resection weakens the strength that our eyes can withstand when subjected to external shock, the use of keratotomy is decreasing recently. It is used as a method in combination with the city.
Plastic ring implantation has limitations in that long-term results are not yet available and its predictive power is poor. Recently, as a method to reduce astigmatism during cataract surgery, an artificial lens for astigmatism correction has been introduced and is in the spotlight.
Astigmatism is difficult to call a disease, and there are no special complications.
Astigmatism usually does not progress or change significantly, unless there is something special enough to cause an ophthalmic abnormality. It is recommended that you have regular eye exams to check for refractive errors in your eyes and correct them if there are any.
In particular, when a child turns 3 years old, they should undergo an ophthalmological examination to check for refractive errors and correct them with appropriate glasses. Avoid reading in the dark or in a shaky vehicle or working at close range for extended periods of time.
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This information is a reference material to help you understand health information.
In order to accurately determine the patient's symptoms and disease, it is necessary to see a doctor.
