In most cases, astigmatism in children is hereditary and predetermined genetically. In this case, the child has a congenital violation of the sphericity of the cornea or lens. Astigmatism of a high degree in children may be accompanied by albinism, congenital retinitis pigmentosa, fetal alcohol syndrome.
Acquired astigmatism in children occurs with corneal scars, surgery and eye injuries, lens subluxation, accompanied by a rupture of the ligament of Zinn. Often, astigmatism in children develops due to the pathology of the dentition, which causes deformation of the walls of the orbit.
In astigmatism in children, associated eye diseases can be detected: keratoconus, congenital nystagmus, ptosis, optic nerve hypoplasia.
The direct cause of astigmatism in children is a violation of the sphericity of the cornea or, less commonly, irregular curvature of the lens. Therefore, the light rays after refraction in optical media are scattered and create several foci on the retina at the same time. In this case, the child sees objects distorted and unclear. Over time, astigmatism in children leads to a secondary decrease in visual acuity and the development of amblyopia.
Classification of astigmatism in children
Astigmatism in children may be physiological or pathological. Physiological astigmatism in children is characterized by the difference in the refraction of the two main meridians of less than 1 diopter; does not affect visual acuity and does not require treatment. The emergence of physiological astigmatism is associated with uneven growth of the eyeball in children. In the case of pathological astigmatism in children, the difference in refraction exceeds 1 diopters, and therefore is accompanied by a decrease in vision.
Also in children’s ophthalmology distinguish between correct and incorrect astigmatism.
In this case, the correct astigmatism in children can be of several types:
- simple hypermetropic – with normal refraction of one main meridian and hypermetropic – another;simple myopic – with normal refraction of one main meridian and myopic – another;
- complex hypermetropic – with hypermetropic refraction of both main meridians, but expressed in varying degrees;
- complex myopic – with myopic refraction of both main meridians, but expressed in varying degrees;
- mixed – with myopia in one meridian and hypermetropia – in another.
The following signs are characteristic of abnormal astigmatism in children: a spasmodic, rather than a smooth transition of refraction from one main meridian to another; non-perpendicularity of the main meridians relative to each other; different refraction of different parts of the same meridian.
The degree of astigmatism in children is judged by the difference in refraction in both main meridians. Based on this, there are 3 degrees of astigmatism in children: weak (less than 1 diopters), medium (from 3 to 6 diopters) and high (over 6 diopters).
Symptoms of astigmatism in children
Astigmatism can occur in children of any age. The parents may suspect astigmatism in the child if they notice that he is tilting his head or squinting his eyes while looking at the image; often stumbles or stumbles when walking, touches the corners of the furniture, puts objects past the table, hardly focuses the eye on the printed text, pulls the outer corner of the eye with a finger.
Children with astigmatism may complain of blurred vision, poor vision of objects near or far, distortion of visible objects, sensations of visual discomfort, visual fatigue, fatigue and eye irritation, headache due to visual load, double vision.
Uncorrected astigmatism in children can lead to a delay in the development of the visual system as a whole and the occurrence of strabismus and amblyopia.
Since children adapt well to visual impairment, there may not be subjective signs of impaired refraction. In this regard, a special role in identifying astigmatism in children belongs to dispensary examinations of the child by a pediatric ophthalmologist.
Diagnosis of astigmatism in children
Most often, astigmatism is diagnosed during examination of children of the second year of life. In astigmatism in children, it is necessary to conduct a comprehensive assessment of the state of the eyes and visual function.
The diagnostic algorithm includes visometry, biomicroscopy, ophthalmoscopy, eye ultrasound and ophthalmometry, which allow to identify concomitant eye pathology and the likely cause of astigmatism in children.
Refraction assessment is performed by performing a shadow test (skiascopy) with spherical or cylindrical lenses, autorefractometry, keratometry, computer keratotopography.
As a result of a complete examination, the ophthalmologist determines the presence, degree and form of astigmatism in children.
Treatment of astigmatism in children
Correction of astigmatism in children is carried out by conservative methods. Refraction operations (laser correction of astigmatism, keratotomy, etc.) are recommended after 18-20 years, when the visual system is already fully formed.
In astigmatism of a weak degree, not complicated by hyperopia or myopia, as well as subjective symptoms, correction is usually not required. In other cases, children with astigmatism are shown picking glasses or contact lenses.
For the correction of simple astigmatism in children, cylindrical lenses are used; for the correction of complex and mixed – spherocylinder lenses, combining spherical and cylindrical glass. The optimal method of correcting astigmatism of any kind is contact correction, which contributes to a clearer focusing of the image on the retina. Contact lenses require careful handling and special care, which limits their use in young children.
One of the ways to correct astigmatism in children is orthokeratology, which involves wearing hard contact lenses that temporarily correct the curvature of the cornea. OK lenses are worn only for the night, for the period of sleep, and are suitable for children who absolutely refuse to wear glasses or contact lenses. Orthokeratotherapy is used for astigmatism in children not exceeding 1.5 diopters.
Parents should be aware that glasses and contact lenses do not cure, but only correct astigmatism in children, improving visual function. Completely get rid of astigmatism is possible only with the help of surgical intervention.
Prevention of astigmatism in children
The degree of congenital astigmatism tends to decrease during the 1st year of life. For most children, by the age of 7, the degree of astigmatism stabilizes. In the absence of correction with age, both a decrease and an increase in the degree of astigmatism are possible. Timely undertaken correction of astigmatism in children contributes to increased visual acuity, the possibility of reducing the strength of glasses or the complete rejection of glasses. When astigmatism is high, refractive strabismus and amblyopia may be developed without undergoing eye correction.
Children with astigmatism should be observed by an ophthalmologist and undergo a routine examination twice a year. Since children have a constant growth of the eye, it is necessary to monitor the timely change of optics.
To reduce the risk of astigmatism in children, it is necessary to alternate visual loads with eye exercises, moving rest. Useful swimming, a contrast shower, massage the cervical-collar zone, good nutrition.
Astigmatism in children is a refractive disorder of vision, accompanied by a change in the sphericity of the cornea or lens and their refracting properties. Astigmatism in children can cause reduced vision, dizziness, migraine-like headache, strabismus. Diagnostics of astigmatism requires examination of children by an ophthalmologist: skiascopy, autorefractometry, determining the degree of astigmatism using cylindrical lenses, keratometry, computer corneal topography, checking visual acuity, etc. To correct astigmatism in children, glasses or contact lenses are prescribed, OK therapy.
Astigmatism in children is a defect in the refracting medium of the eye, leading to blurring, blurring the image of a visible object. The term “astigmatism” literally translated from Latin means “no focus point”. In astigmatism in children, as a result of irregular corneal curvature (less often the lens), rays emanating from one point cannot be reassembled in a single focus on the retina, as a result of which the image of the object appears blurred and blurry.
- Astigmatism of varying degrees occurs in almost every child, but 90% of children have a small degree (less than 1 diopter), which does not affect visual acuity. However, in 10% of children, astigmatism requires a special ophthalmologic correction. Astigmatism in children is often accompanied by myopia or farsightedness.