Parents ask questions
Hello! Two and a half years old baby has three hundred degrees of astigmatism in both eyes, what should I do? Do you have to wear glasses at all times? Are there any advanced treatments out there?
Thank you for your question and trust!
Next, I will answer you the prevalence, nature, negative effects, and treatment of high astigmatism in simple vernacular.
Astigmatism is common among Chinese children, high astigmatism is uncommon
Astigmatism above 300 degrees is called high astigmatism. 2.2% of Chinese school-age children have high astigmatism, and 14.2% of children have astigmatism above 150 degrees . As the rate of myopia increases, the degree of astigmatism will increase . For example, 20% of children in the third grade of junior high school have astigmatism of more than 150 degrees, and 20-25% of high school students have astigmatism of more than 150 degrees .
The prevalence of astigmatism in children under 6 years old: 13.8% of 3-year-old children have astigmatism of more than 125 degrees , and 12.7% of children aged 4-6 have astigmatism of more than 100 degrees .
Astigmatism is usually inherited
Astigmatism is not a disease, but a measure of the precision of the lens of the eye camera, such as the optical imperfections of the front and rear surfaces of the lens. A high degree of astigmatism is congenital, usually rooted in the imperfect shape of the cornea. The cornea was the first camera lens of the human eyeball camera. The perfect corneal shape would be a hemispherical shape (left in the image below), and the shape of a cornea with high astigmatism would be a football (right in the image below).
Looking at the picture above, the cornea is a hemispherical equatorial line K1 radian and the north-south line K2 radian. If the values of K1 and K2 are close, then the astigmatism of the cornea is very low, even 0, so the total astigmatism of the eyeball camera is also usually below 75 degrees. If the values of K1 and K2 are very different, then the astigmatism of the cornea is high, and the total astigmatism of the eyeball camera is usually higher than 300 degrees. Therefore, a cornea with high astigmatism is like other imperfect human anatomical structures, such as short limbs, a flat nose… just imperfect, not a disease. In adulthood, corneal refractive surgery can re-sculpt the central area of the cornea into a perfect hemisphere, correcting high astigmatism once and for all.
Corneal K1 and K2 usually have a high genetic predisposition , that is, the parents are likely to have high corneal astigmatism, and may also be passed on to the next generation. Therefore, you and your husband need to screen for high astigmatism, and the person with high astigmatism needs to do Pentacam corneal topography to rule out keratoconus . You don’t have to worry too much that your child will have keratoconus. The incidence of the latter is very low, and it can be ruled out by annual eye examination. The incidence of keratoconus in children is 0.53%, and the incidence of keratoconus in people >14 years old is 3.78% .
Negative effects of high astigmatism
After going to school, it affects distance vision (can’t see the small characters on the blackboard clearly), the key is to affect the reading speed , which is not conducive to learning and exams; it also affects sports performance , such as running down stairs, not good at ball games, etc. Wait.
High astigmatism can only be corrected, not cured. High astigmatism of the cornea is usually fixed by about 2 years of age . Therefore, do not rely on food, glasses, vision training, acupuncture massage, drugs, etc. to reduce corneal astigmatism.
If the uncorrected visual acuity is less than 0.3 and the corrected visual acuity is less than 0.5 when the child is 3 years old , he must wear glasses to correct high astigmatism.
Before the age of 5, you can choose to wear spectacles to correct high astigmatism. The goal of correction is to achieve a visual acuity of more than 0.5 with glasses and a near-stereoscopic vision of less than 100 arc seconds.
After the age of 5, RGP , a hard contact lens, is more common in foreign countries. RGP brings higher vision and more refined visual quality than frame glasses and is suitable for school-aged children. The goal of correction is to achieve 1.0 visual acuity with glasses and a near-stereoscopic vision of less than 40 arc seconds.
At the age of 18, you can undergo corneal refractive surgery or intraocular lens implantation.
I hope my answer is helpful to you, and good luck!
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