What Are the Most Common Symptoms of Amblyopia in Children?

Those who have no organic lesions in their eyes and whose corrected vision is lower than 0.9 are called amblyopia. Amblyopia is a common eye disease in children in clinical ophthalmology. It is a state of visual impairment that occurs when infants and young children fail to receive appropriate visual stimuli due to various reasons such as perception, movement, conduction, and central vision. , Mainly manifested as low vision and binocular monocular dysfunction.

Basic Information

English name: Amblyopia
Visiting department: Ophthalmology
Multiple groups: child

Common locations: eye
Common causes: Failure to accept appropriate visual stimuli due to perception, movement, conduction, and visual center, affects visual development
Common symptoms: Low vision, monocular dysfunction in both eyes

Causes of Amblyopia in Children

Strabismic amblyopia

The amblyopia in children with unilateral gaze is often caused by amblyopia in children. In order to eliminate diplopia and visual disturbance, the visual cortex center actively inhibits the visual impulses input by the macula in strabismus. Function is inhibited for a long time to form amblyopia, that is, the consequences of visual confusion caused by visual confusion.

2. Ametropic amblyopia

The refractive errors of the two eyes are large, which makes the retinal imaging unequal in sharpness or the size of the retinal imaging after correction. The fusion is difficult. The visual cortex centrally suppresses the object image from the eye with the larger refractive error, and the long-term inhibition occurs amblyopia.

3. Deprived amblyopia

In infants and young children due to opaque interstitial opacity, complete ptosis, congenital (such as eyelid hemangioma), iatrogenic (such as covering), etc., preventing light stimulation from entering the eye, preventing macular acceptance Stimulation inhibits visual function development. If it occurs during the visually sensitive period (before 3 years old), it is more likely to form amblyopia.

4. Ametropia

Unilateral or bilateral, occurred in children with high refractive error without corrective glasses, often with high hyperopia or astigmatism, due to limited adjustment. He did not wear corrective glasses, and could not obtain a clear object image for far and near objects, and formed amblyopia.

Classification of amblyopia in children

1. Mild amblyopia: vision is 0.8 to 0.6.

2. Moderate amblyopia: vision is 0.5 to 0.2.

3. Severe amblyopia: vision does not exceed 0.1.

Clinical manifestations of amblyopia in children

Often asymptomatic or low vision in one eye, the visual acuity and corrected vision of amblyopia are lower than 0.9. Coverage, strabismus, and / or extraocular muscle surgery in childhood. The corrected visual acuity is lower than that of normal children of the same age, and most of them are monocular or both. Visual targets of the same size are easier to recognize individually than arranged in a row.

Strabismic amblyopia

Amblyopia may occur in children with common strabismus in childhood because both eyes cannot focus on the same object at the same time. Because the child's brain is relatively easy to adjust and adapt, it will inhibit the relatively blurred image obtained at one glance, interfere with the visual development of the brain, and cause the vision of the eye to decline, that is, amblyopia. When the degree of deflection of the eyes is small, it is difficult to detect. However, those with a small degree of strabismus may also develop severe amblyopia, which should not be ignored clinically.

2. refractive amblyopia

Amblyopia can cause amblyopia. Eyes with lower refractive errors provide a relatively clear retinal image. The brain selects the image of that eye and suppresses the blurred image of another eye with a high refractive error, causing the amblyopia of the eye. . Children with asymmetric hyperopia need special vigilance, because the adjustment of the two eyes is equivalent, and only the image of one eye can be focused at the same time, and the eyes with high hyperopia can be suppressed because they cannot focus clearly. The severity of refractive amblyopia is not significantly different from strabismic amblyopia.

3. Form Deprivation and Covering Amblyopia

The main reason is that the ocular refractive medium is cloudy or opaque, such as cataracts, corneal scars, etc., which restricts sufficient visual perception input and disrupts visual development. This amblyopia may persist even after the opaque medium is removed. Covering amblyopia has a low incidence, which usually occurs in covering normal eyes.

Amblyopia in children

No special laboratory inspection is required.

General inspection

Visual inspection, external eye and fundus examination, refractive examination, strabismus examination, fixation examination, binocular monovision examination, retinal correspondence examination, fusion function examination, stereo vision examination.

2. Laser interference visual acuity (1aserinterferencevisualacuity, IVA)

3. Contrast sensitivity function

The contrast sensitivity function (CSF) measurement is the ability of the human eye vision system to recognize sinusoidal grating sight targets with different spatial frequencies under bright contrast changes. It can be used as a sensitive, accurate, and quantitative detection from a time and space perspective. An indicator of visual function in patients with amblyopia, which reflects not only the resolution of the sight on small targets, but also the resolution of coarse targets.

4.VEP vision

Sokol measured some infant and adult image VEP (pattern VEP, PVEP) and found that infants and young children had the strongest response to a checkerboard with a viewing angle of 7.5 or 15 at 6 months, which is the same as 20/20 vision of adults. At 6 months, infants and young children have established a 20/20 visual function. The measurement method is to use checkerboard stimulation, and the squares become smaller until the VEP that can measure the smallest amplitude is induced. At this time, the highest spatial frequency represents the most Good vision.

5. Electrophysiological examination

(1) Electroretinogram with simple light stimulation (F-ERG), there is no significant difference in electrical response between amblyopic eyes and normal eyes. Sokol reported that using graphic electroretinogram (P-ERG) to check the b-wave amplitude and The amplitudes of the posterior potentials have all decreased. Through domestic research, Yin Zhengqin and others found that the P-ERG response of strabismus decreased, and that the visual function damage caused by strabismus also involved the retina and the visual center.

(2) Visually evoked potentials (VEP) The nerves are excited after the retina receives light or specific graphic stimulation, which is transmitted to the visual center through the visual pathway. Using modern microelectrode technology and computer technology, these potential activities can be recorded to obtain visual evoked potentials. Potential (VEP).

(3) Multi-view VEPs (12 to 48 electrodes ) with full-view or half-view stimulation, multi-view visual evoked potential topography , can observe the entire skull surface (especially the skull surface covering the visual cortex) at a certain moment after stimulation. The distribution and change of VEPs in the dimensional space. Based on this, the potential values collected by each electrode are processed by the computer, and points of the same polarity and value are connected to form an isoelectric map of VEPs, that is, a multi-conductor VEPs topographic map, which can be dynamic. Image, visually show EEG activity after visual stimulation.

6. Auxiliary inspection

(1) Except for detailed follow-up examinations, except for organic causes of low vision.

(2) Concealing-Deconcealing test to check eye position.

(3) Retinoscopy: Retinoscopy is performed under ciliary muscle paralysis to determine the refractive status.

Diagnosis of amblyopia in children

Visual inspection is an important way to find amblyopia or strabismus in children. It can also find congenital eye diseases such as cataracts, glaucoma, and retinoblastoma. Regular inspections can be found early and treated or corrected early. Visual function tests can be performed within a few months after birth, and vision tests can be performed around the age of 3.

Differential diagnosis of amblyopia in children

The disease should be distinguished from strabismus.

Amblyopia treatment in children

(A) treatment principles

Resume vision function

Eliminate inhibition, improve vision, correct eye position, and train macular fixation and fusion functions to restore binocular vision. The treatment effect of amblyopia is related to age and fixation. It is better at 5 to 6 years old, and worse at 8 years old; central fixation is better, and lateral fixation is poor.

2. Treatment summary

Amblyopia must first wear corrective glasses to correct refractive errors. Cover the healthy heel, force the amblyopia to fixate and perform fine work. Over-corrected or under-corrected lenses and daily atropine methods are used to suppress eye health. A red film with a wavelength of 620 to 700 nm was affixed to the lens of the central gaze.

The best time to treat amblyopia is 2 to 6 years old. Generally, children over 12 years of age are difficult to treat and it is difficult to improve their vision. This is because 2 to 6 years old is the visually sensitive period of infants and young children.

(Two) treatment measures

1. Correct the cause of amblyopia

First wear corrective glasses to correct refractive errors. Early treatment of congenital, traumatic cataracts and complete ptosis.

2. Covering therapy

Divided into full and partially covered. The purpose is to cover the healthy heel, force the amblyopia to fixate and perform fine work. The time and method of concealment should be selected according to the age, vision and gaze characteristics of the child. In young children, to prevent covering amblyopia can cover healthy eyes for 3 to 6 days, and cover amblyopia for 1 day. Follow-up visits every 3 to 6 weeks. Cover until the eyesight is equal or the vision no longer improves, use partial covering therapy instead. If amblyopia occurs when covering the eye, cover the contralateral eye for a certain period of time and follow up closely. If the amblyopic eye is treated and the visual acuity improves to 1.0, the full cover should also be changed to a partial cover. Open the healthy eye for 2 hours a day. After 1 month, if the vision does not decrease, open it for 4 hours a day and gradually change to 6 hours, 8 hours, open all day.

3. Depression therapy

Overcorrected or undercorrected lenses and daily atropine methods are used to suppress the healthy eye function, and the amblyopic eyes wear normal corrective lenses. Depressive therapy includes depressive looking far, depressive looking near, complete depressive, and alternate depressive. It is suitable for children with moderate amblyopia, older age and unwilling to do cover treatment.

4. Visual stimulation therapy

(1) Vision stimulator (CAM), also called grating therapy, is used for central fixation and ametropia. In this method, bars with strong contrast and different spatial frequencies are used as stimulation sources to stimulate amblyopic eyes to improve vision. The thinner the bars, the higher the spatial frequency. Cover the healthy eyes during treatment, 7 minutes each time, once a day, 10 days as a course of treatment. With the improvement of vision and the interval of treatment time, the time gradually increases.

(2) After-image therapy The purpose of this treatment is to change the side-centered amblyopia to central gaze, in order to improve the visual acuity of the amblyopic eye and cover the amblyopic eye, and cover the healthy eye during treatment. This method is suitable for concentration, can In combination with the treatment of older children, and other methods of ineffective paracentric amblyopia.

(3) The red filter method usually covers healthy eyes, and a regular red filter film (wavelength 640nm) is added to the amblyopia correction lens to change the side-center amblyopia to amblyopia. When changing to center gaze, remove the red filter and continue with the routine masking method.

5. Red film method

It is suitable for side-center gaze, and a red film with a wavelength of 620 to 700 nm is pasted on the lens of the side-center gaze, and it is affixed for 2 to 3 hours daily.

6. Perceptual training

Such as network amblyopia training based on neuroscience and visual science.