Overview
Amblyopia is a condition in which the corrected visual acuity of one or both eyes does not reach 1.0 without obvious organic lesions. Currently, the standard for amblyopia in China is corrected visual acuity ≤ 0.8 or difference in visual acuity between the two eyes ≥ 2 lines. Amblyopia is an eye disease that seriously endangers the visual function of children.
1, to fully understand that the process of amblyopia treatment is slow, vision is gradually improved, parents should have patience and persistence.
2. It is important to patiently persuade the child to insist on wearing glasses, especially when covering the healthy eye, except for bathing and sleeping. The legs of the glasses should be connected with a chain to prevent them from breaking.
3.Guide your child to always wear glasses when looking at near objects, especially when drawing and writing, so that you can often achieve twice the effect.
4.For children with moderate or severe amblyopia, in addition to wearing glasses, insist on amblyopia training treatment at the hospital. Parents who apply amblyopia stimulators should encourage their children to draw pictures carefully and try to draw accurately.
Children aged 2 to 3 years old should have their eyes examined every two weeks, while older children should have their eyes examined every month, and their eyes should be dilated once a year. In short, due to the young age of children and poor self-control and other factors, it is very important for parents to be patient and guide their children to treatment.
Etiology and classification
1, strabismic amblyopia: In order to overcome the visual disorder and diplopia caused by strabismus, the visual center actively inhibits the vision of the strabismic eye, and over time, amblyopia is formed. According to statistics, about 50% of children with strabismus have amblyopia.
Amblyopia due to lid sutures, severe ptosis, or long-term masking of the eye to prevent light from entering the eye, which affects the development of the macula.
Refractive amblyopia: This condition is common in patients with refractive error in both eyes without corrective glasses, which causes amblyopia because the central macular sulcus optic cells are not fully stimulated for a long time.
4, refractive parametric amblyopia: due to the difference in refractive error between the two eyes of more than 3D, the difference in the size of the macula of both eyes is about 5%, making the brain fusion difficulties, resulting in long-term inhibition of the cerebral cortex to the eye with higher refractive error (or too small object), and amblyopia occurs over time.
5.Congenital amblyopia: This condition may be related to macular hemorrhage in newborns, which affects the normal development of optic cell function; or nystagmus, unable to gaze and visual impairment.
Symptoms
Low visual acuity in one or both eyes, often below 0.3 and not correctable with lenses, with normal fundus examination. The recognition of a single visual marker is much higher than the recognition of visual marks arranged in rows of the same size (enhancing 2 to 3 rows), which is called crowding phenomenon or difficulty in separation. This is called crowding phenomenon or difficulty in separation. Such patients are mostly accompanied by eye position deviation or nystagmus, abnormal nature of gaze and other characteristics.
1, first of all, parents should understand that the normal visual acuity of children of different ages is not the same, and the development of normal children’s vision is gradually improved as children grow. The normal visual acuity of our children at different ages is: 0.5 to 0.6 at age 2; 0.9 at age 3; 0.9 to 1.0 at age 4; and 1.0 or more at age 5 and above. Generally children’s vision development stabilizes between the ages of 6 and 8. If this is not understood it is easy to mistake a child with normal vision for amblyopia.
2, guide the child in looking at near objects, must wear glasses, especially when drawing, writing, so that often can achieve twice the effect.
3, to children in the early years of vision examination, once found myopia, farsightedness, astigmatism and other refractive errors, should be timely under the guidance of professionals to wear the appropriate degree of glasses, so as to avoid the development of amblyopia.
4. Be patient and persuade your child to insist on wearing glasses. In addition to bathing and sleeping, you must insist on wearing glasses, especially when covering the healthy eye, which is very important, and the legs should be connected with a chain to prevent the glasses from breaking.
5, after the child has amblyopia, have a correct understanding of amblyopia as a disease, to fully understand that the process of amblyopia treatment is slow, vision is gradually improved, can not be too hasty, have patience, persistence.
Clinical examination
1. Visual acuity examination. It is important to check the vision of children as early as possible. The following are several methods of vision examination for infants and young children: newborn infants can be determined early by pupil-to-light reflex and funduscopic examination to determine whether there are any abnormalities in the eye. 3 months to 2 years old children are observed to see whether there is light chasing in both eyes; whether there is aversion after masking, whether the vision moves with the target, and whether the object can be tracked and grasped for the initial evaluation of visual function, and the selective viewing method and visual evoked potential examination can also be used. The graphical visual acuity chart is suitable for children aged 2 to 3 years, and children aged 3 to 4 years or older with normal cognitive development should learn to read the E-type visual acuity chart, and can be given the international standard visual acuity chart and individual visual acuity for examination respectively. For children who are uncooperative, hospitals can also use computerized photographic optometry, which can screen for obvious refractive errors, refractive aberrations, refractive media clouding and strabismus under small pupils.
2.Refractive state examination. Use 1% atropine ophthalmic ointment applied to the conjunctival capsule, 3 times a day, dilate the pupil for 3 days after the retinal examinations to determine the refractive state to be corrected, and 3 weeks after the reopening. Infants and children can be initially judged and predicted by the refractive power used in funduscopic examination.
3.Eye position examination. Through corneal reflection method, masking test, trigeminal lens, malleolus rod, synoptic machine, etc., to determine whether there is strabismus and the angle of self-perceived strabismus and other perceived strabismus.
4.Trigonometry examination. To induce eye strabismus by 15△~25△ trigonometry, combined with the masking test to check the type of gaze of the child, then determine amblyopia and determine the degree of amblyopia. It is mainly used for preschool children who are unable to cooperate in the visual acuity check. The child is asked to look at the sight mark with both eyes, and a 15△. 25A trigonometric prism with a downward base is placed in front of the right eye to create a vertical separation between the eyes. If the right eye appears to move upward to re-gaze, it means that the right eye is gazing, and it is a continuous gaze. If there is no upward movement of both eyes after placing the mirror, the left eye is gazing (the left eye is the gazing eye). When the left eye was covered to force the right eye to gaze with the tricorder placed, and the left eye was uncovered, if the right eye continued to gaze for more than 5 s or could gaze at the target after blinking (holdthroughblink), it was still sustained gaze. If the right eye gaze did not last until the blink or lasted more than 2 s, the gaze was not continuous. The same procedure was repeated with the trigeminal lens placed in front of the other eye. If both eyes respond equally to this examination, respectively, as sustained fixation, the patient has equal or similar visual acuity in both eyes and may have binocular monovision. Some patients with refractive amblyopia have lower than normal visual acuity but can be equal, and the possibility of persistent binocular fixation cannot be excluded. Non-persistent fixation can be divided into: (1) gaze can last until blink, but after blink can no longer gaze (holdtoblink, notthroughblink), the patient has mild amblyopia. If the gaze lasts for a very short time of only about 2s, the patient has significant amblyopia. ③If the gaze cannot be sustained at all, i.e., the eye without trigeminal mask is removed, and the eye with trigeminal lens immediately loses gaze, the eye has severe amblyopia.
5. Slit lamp and fundoscopic examination. In addition to slit lamp and fundoscopic examination to exclude organic eye disease, children with amblyopia can also be classified into 4 types of gaze by using the black star target detector.
(1) central gaze – the macular central concave light reflection is exactly in the center of the black star, if it floats slightly on the black star central concave light reflection but does not go beyond the central concave range, then it is unstable central gaze.
(2) Paracentral concave gaze – outside the central concave of the black star but within the 3. ring.
(3) Macular gaze – the black star is between the 30 and 5 rings of the central concavity.
(4) Peripheral gaze – the black star is between the macular limbus and the optic papilla, and occasionally on the nasal side of the optic papilla. Clinically, it is generally classified as central gaze or paracentral gaze amblyopia. The farther the point of gaze is from the central recess, the worse the visual acuity of the amblyopic eye. Paracentral gaze can be divided into stable and wandering, with wandering having a better prognosis than stable. For monocular amblyopia with little difference in refractive status and no strabismus, attention should also be paid to macular ectasia. Fundus color examination under dilated pupil can be performed routinely to determine whether the macular position is normal.
6. Contrast sensitivity function (CSF). In amblyopic eyes, the CST curve is low and the peak is left shifted.
7.Visual electrophysiological changes. PERG shows a decrease in b-wave amplitude and PVEP shows a decrease in amplitude and prolonged latency. There are also clinical studies of visual electrophysiological changes in different types of amblyopia using multi-conductor graphic VEP and multi-focal VEP.
Key points of eye examination for children with amblyopia
1. For children who have reached the age of one year, regardless of whether both eyes are found to be normal or not, a comprehensive examination should be routinely done by a professional ophthalmologist to see if there is a possibility of pediatric amblyopia. Under normal circumstances, children should have normal vision when they reach the age of 4 years old when their eyes are mature.
2. Kindergarten children should have their vision checked every 6 months for early detection of pediatric amblyopia.
Common treatment methods for children with amblyopia
1.Piercing needle and bead training: After the child wears corrective glasses, he or she should pierce needles or beads with red thread, and wear 200-300 needles or 200-300 beads each time to prompt more near vision. To improve visual acuity.
2, red light flicker stimulation method: after the child wears corrective glasses, use the amblyopic eye to look at the flickering red light from the observation hole for 10-15 minutes each time, twice a day.
3.Treatment for young children: Checking the visual acuity of young children can be done with a children’s visual acuity meter, or with toys of different sizes at different distances to estimate the visual acuity of young children. The most accurate and reliable test is the visual evoked potential method. 1-2 year old children who are found to have amblyopia in one eye can be treated with 1% atropine ointment applied to the healthy eye under the guidance of a doctor once a day for three weeks and then rested for a week as a course of treatment. After each two sessions, the child will be examined and a decision will be made whether to continue treatment. The above treatment can be continued until the child is able to cooperate with the dilation of the pupil and the fitting of glasses. The purpose of treatment with atropine ointment is to cause temporary blurring of vision in the healthy eye and to force the amblyopic eye to look at external objects as a priority and improve visual acuity.
4.Covering treatment: After the child wears corrective glasses, under the guidance of the doctor, the eye shield made of plastic or black cloth is used to cover the healthy eye completely, forcing the amblyopic eye to look at objects, so that the amblyopic eye gets exercise and increases vision. The number of days to cover the healthy eye and the ratio of alternate coverage of both eyes should be flexible according to the child’s visual acuity and age. Covering the healthy eye should be thorough, so that the child cannot use the healthy eye to peek, and the masking therapy should be constant and cannot be interrupted, otherwise it will obviously affect the efficacy. Special attention should be paid to check the visual acuity of both eyes every 4 weeks of masking therapy to observe whether there is any progress in the visual acuity of the amblyopic eye and whether there is any regression in the visual acuity of the masked eye. If the vision of the covered eye does not regress, the masking can be continued. If the vision of the covered eye regresses, the masking should be stopped for a number of days, and the masking treatment should be continued after the vision of the covered eye has recovered.
Complete masking method: On the eyeglass lens of the eye with good vision, put an opaque paper, then let the patient do some fine activities such as drawing, picking sesame seeds, threading beads and so on. This method is suitable for amblyopic eyes with visual acuity above 0.3.
Partial masking method: Using transparent cellophane glued to the lens of the eye with good vision, so that its vision is 0.1 to 0.2 lower than the vision of the amblyopic eye after wearing these translucent glasses, and often do some fine activities for exercise. It is suitable for those who have a small difference in visual acuity between the two eyes and whose visual acuity in the amblyopic eye has improved to normal or close to normal after treatment with complete masking method.
5, optical drug suppression therapy: the application of this method is more complex, need to be implemented under the guidance of a doctor. First of all, the pupils of both eyes are examined, the refractive error is fully corrected, and the refractive error of both eyes is adjusted according to the visual acuity of the amblyopic eye, and then glasses are prescribed. Then, 1% atropine drops are applied to the healthy eye once a day, forcing the amblyopic eye to look far or near, in order to exercise the amblyopic eye and make the amblyopic eye’s visual acuity progress.
Why can’t children be cured of amblyopia?
1, only to the child wear myopic glasses, no other treatment: treatment of children with amblyopia, the child wears myopic glasses is only an emergency measure, and can not completely solve the problem, in order to completely solve the problem must be on this basis, with other methods of treatment, such as the use of masking therapy, visual stimulator therapy, etc., otherwise, such children will grow up, even if wearing myopic glasses, vision will be very poor. In addition, some amblyopic children wear a pair of nearsighted glasses for several years, which is also wrong. This is because as the child’s body develops, its refractive error will change, so amblyopic children should be re-opened every six months to a year, if necessary, to refit myopic lenses.
2, can not adhere to the use of masking therapy: amblyopia masking therapy is mainly through the healthy eye or the dominant eye cover, forcing the child to use the amblyopic eye to see things, so as to eliminate the inhibition of the eutropic eye to the amblyopic eye, to achieve the purpose of enhancing the vision of the amblyopic eye. It is a traditional method of treating amblyopia, which is convenient, economical and effective. However, because covering the eye affects the appearance of the affected child and can cause ridicule from other children, many amblyopic children are reluctant to undergo covering therapy. Some parents, out of compassion for their children, let it happen. If you cannot insist on using masking therapy, of course, you will not be able to achieve the purpose of treating amblyopia.
3, ignore the training of visual function of both eyes: childhood is the period when the visual function of both eyes (simultaneous vision, fusion vision, stereopsis) is established, developed and perfected. If a child suffers from amblyopia during this period, it will affect his or her visual development, and in serious cases, he or she will lose the visual function of both eyes and become stereoscopically blind. However, many parents of amblyopic children are not aware of this. They tend to pay attention to the visual acuity training of the amblyopic eye, but neglect the training of the visual function of the child. As a result, not only the treatment effect of amblyopia is greatly reduced, but also the development and improvement of advanced visual functions of the child is affected. Therefore, parents must pay attention to the training of visual function of their children, and should train them in binocular vision at the same time as they train their vision. In addition, parents should bring their children back to the hospital regularly to check the development of their binocular visual function and adjust the treatment plan according to the situation.
4, see the good and accept: children’s amblyopia as long as the treatment is timely, the method is appropriate, will receive obvious results, but easy to relapse. If the treatment is stopped immediately after the effect is seen, without consolidation treatment, the vision of the child’s amblyopic eye will soon decline again. Many parents are not very clear about this point. They often relax or even stop treatment when their child’s vision returns to normal, resulting in a relapse of amblyopia soon after. Therefore, the treatment of amblyopia in children should be a longer period of consolidation treatment after the vision of the amblyopic eye has reached or is close to normal, and a three-year follow-up is required until the child’s vision remains normal before it is considered cured.