Amblyopia is the result of insufficient visual stimulation entering the eye during the critical period of visual system development due to various reasons, depriving the opportunity to form clear images and/or different visual input from both eyes, causing competition between clear and blurred images, resulting in the best corrected visual acuity in one or both eyes being lower than the corresponding age visual acuity, or the difference in visual acuity between the two eyes being 2 lines or more.
The normal visual acuity of children in different age groups is different. If the visual acuity is below the lower limit of normal, the difference in binocular vision is less than two rows, and no risk factors for amblyopia are found, a hasty diagnosis of amblyopia is not advisable.
What are the causes of amblyopia?
1. Strabismic amblyopia
In children with strabismus, the object images of both eyes do not fall on the corresponding points of normal retina, causing diplopia and visual confusion, and the patient feels discomfort.
2. Refractive parallax amblyopia
The refractive difference between the two eyes is more than 2.5 diopters, resulting in unequal size of retinal imaging between the two eyes and difficult fusion. One eye with heavy refractive error is inhibited and its function is not well developed, resulting in amblyopia.
3. Refractive amblyopia
Mostly binocular, occurring in patients with uncorrected refractive error, the visual system does not receive clear visual image stimulation, resulting in amblyopia.
4. Formal deprivation amblyopia
In early infancy, amblyopia is caused by insufficient visual stimulation due to corneal clouding, cataracts, ptosis, or overshadowing of one eye for too long.
5.Amblyopia caused by other reasons
Such as nystagmus, etc.
Amblyopia should be detected and treated early. Parents should take their children to the eye examinations early and start treatment immediately if the doctor confirms that the child is amblyopic. Generally speaking, treatment under the age of 12 is very effective, and the best time to treat is between the ages of 3 and 6.
Treatment methods include
1. Correction of refractive error and relief of form deprivation
Early correction of refractive errors, treatment of congenital cataracts, congenital ptosis, etc., and removal of interfering factors that cause amblyopia.
2., masking therapy
This method is simple and easy to implement. The duration of masking is decided according to the age of the child and the visual acuity of the amblyopic eye. In the process of masking, attention should be paid to the possibility of masking amblyopia in the healthy eye, and the visual acuity of both eyes must be reviewed regularly to adjust the treatment method in time.
3. Inhibition therapy, grating stimulation therapy, drug therapy, etc.
The younger the age, the higher the efficacy. However, amblyopia training should not be limited to the age limit of 12 years old, and there is no shortage of children above 12 years old who have received good results.
The effect of amblyopia treatment is also related to the degree of amblyopia, with mild amblyopia having high efficacy, moderate amblyopia having the second highest efficacy, and severe amblyopia having the worst efficacy; and the nature of gaze, with central concave gaze having good efficacy and peripheral gaze having poor efficacy. The goal of amblyopia treatment is not only to improve visual acuity, but also to establish binocular stereopsis.