Causes of development and treatment of mixed astigmatism
Mar 05, 2018
The most complex and heavily treatable form of astigmatism is the mixed astigmatism of , in which one longue eye is marked by hyperopia, and in other words - nearsightedness.That is, one or both eyes of the patient simultaneously see badly both afar and near.
Mixed astigmatism develops due to complex curvature of the cornea of the eye or lens( when there are convex and concave areas in different planes).The image is focused in part before and partly behind the retina.Causes Symptoms Diagnosis Treatment of mixed astigmatism Surgical treatment of mixed astigmatism
Reasons forRecommended reading:
Mixed astigmatism can be both acquired and congenital. The following conditions most often occur as the cause of the acquired form of the disease:
- Injuries to the eye.Operative interventions on the organ of vision.
- Infectious diseases of the cornea of the eye( eg, herpetic keratitis).
- Keratoconus is a cone-shaped deformation of the cornea, which develops due to the thinning and degeneration of the cornea.
In its turn, the congenital form of mixed astigmatism is a problem inherited. Therefore, parents who have or have this disease should regularly take the child to a pediatric ophthalmologist to promptly identify the pathology and begin treatment.
The main symptom of mixed astigmatism is a visual impairment.The patient can not check the objects, determine their size and distance to them. In addition, there are pathological signs that are characteristic of other forms of astigmatism:
- Rapid eye fatigue.
- Pain in the superciliary area.
To suspect mixed astigmatism in children who can not always describe their state of health, it is possible by the following signs: squinting while considering something, unwillingness to read and write, lagging behind in studies, crying, irritability, etc.
The success of treating mixed astigmatism largely depends on how correctly a refractive error( refraction of light rays) in the eye's meridians was determined.To obtain this information, you must visit an experienced ophthalmologist and undergo a complete computer vision diagnosis( including refractometry, keratotopography, vision research with maximally dilated pupils and other methods).
Treatment of mixed astigmatism
Visual disturbances caused by mixed astigmatism are corrected with glasses or lenses.Cure the same disease( that is, eliminate the cause - the curvature of the cornea) can only be through surgical intervention.
Glasses for glasses with mixed astigmatism are always chosen to be spherical-cylindrical, and so that in the meridian with myopia to reduce refraction, and in the meridian with hypermetropia, on the contrary, it should be strengthened.Children are recommended to wear these glasses constantly, as their organ of vision is still growing and developing, and that these processes proceed correctly, vision should be corrected.Adult astigmatic eyeglasses can be prescribed only for certain purposes, for example, for reading.
A more convenient method of correcting mixed astigmatism is hard and soft complex contact lenses.It is clear that for too young patients they are unacceptable.Doctors write out lenses to children only when they can already independently manage them.
Advantages of using contact lenses for mixed astigmatism( when compared with glasses):
- Correctly manufactured( in accordance with all the individual features of the patient's vision) contact lenses are capable of correcting high degree of astigmatism.
- Lenses are a much smaller source of discomfort when worn and do not limit the patient's activity.
- Lenses create optimal conditions for binocular vision( vision with two eyes).
- When using lenses, optical errors are minimized( since the lens fits snugly against the cornea).
To ensure that glasses and contact lenses are really effective, as the visual acuity changes, they need to be changed.To do this, every 6 months to visit an ophthalmologist and undergo computer diagnostics.
Surgical treatment of mixed astigmatism
To cure mixed astigmatism, as mentioned above, it is possible only with the help of surgical correction. In modern ophthalmology, the following types of operations are used for this:
- Laser vision correction.This technique allows you to simulate the curvature of the cornea in the desired meridians, achieving the optimal optical power of the eye in all planes.
- Astigmatic keratotomy, during which microscopic incisions are applied to the surface of the cornea to change the curvature of the cornea and eliminate refractive errors.
To date, laser correction( LASIK / LASIK) is the method of choice for mixed astigmatism.But to apply this kind of treatment, alas, it is possible not in all patients. Contraindications for laser correction include:
- Child's age( up to 18 years, the operation is performed only for individual indications).
- Inflammation in the eye.
- Dystrophic changes and thinning of the cornea( keratoconus).
- Changes in the fundus.
- Diabetes mellitus.Systemic diseases and the like. .
If there are contraindications, ophthalmologists choose other treatment options and correction of mixed astigmatism: glasses, lenses, hardware treatment or other methods of surgical intervention.That is, there is always a choice, the main thing is not to start the disease.
Zubkova Olga Sergeevna, medical reviewer, epidemiologist