tiny degree of strabismus
Introduction
Introduction to Minor Squint Microtropia is a squint angle of view less than 10 (5 °), often combined with varying degrees of amblyopia, paracentral gaze and squint corresponding to abnormal retina. basic knowledge Sickness ratio: 2% Susceptible people: no special people Mode of infection: non-infectious Complications: amblyopia, refractive error
Cause
Minor degree strabismus cause
(1) Causes of the disease
It is not very clear, and may be related to factors such as birth injury and anisometropia.
(two) pathogenesis
At present, the pathogenesis of micro-slant is still not very clear. It is believed that most of the causes of abnormal retinal correspondence in the formation of the macular fovea can cause small-angle strabismus.
1. Injury in infants with retinal hemorrhage at the time of labor, affecting the development of macular function, early inhibition of dark spots in the fovea, and the formation of a fixation point at the edge of the dark spot leads to strabismus.
2. The anisometropia occurs in the early and uncorrected anisometropia, and the opacity of the eye fove is not able to receive sufficient visual stimulation to form a slight oblique.
3. Causes of surgery Internal oblique or external oblique surgery, due to insufficient correction or overcorrection, residual small angle strabismus after surgery.
4. Adjustment causes Regulatory strabismus is not treated. With this age, the hyperopic diopter gradually decreases, the strabismus gradually decreases, and the residual micro-slant.
Prevention
Minor degree strabismus prevention
Early detection and early diagnosis are the key to the prevention and treatment of this disease.
Complication
Minor strabismus complications Complications, amblyopia, refractive error
Amblyopia and refractive error are more common.
Symptom
Minor degree strabismus symptoms Common symptoms Visual impairment center dark spots and flex...
1. The oblique viewing angle is less than 10 , the appearance is not squint, and it is difficult to find by the corneal ray method, the covering method, etc., and most of it is esotropia.
2. Vision "crowding phenomenon", children with reading difficulties, can identify a single font, but it is more difficult to identify the same size and arranged in a row of fonts, that is, the visual acuity checked with a separate visual target is more than that of the parallel visual standard chart. Good eyesight.
3. Non-fixed eyes have a paracentral fixation, and the retina corresponds to a reconciling abnormal retina.
4. Often combined with monocular mild amblyopia, amblyopia has a central dark spot.
5.4 triangular prism bottom test, Worth four-lamp test, Bagolini linear lens test and other inspection methods, can be found in binocular vision abnormalities, monocular gaze, the other eye has a small inhibitory central dark spot; no macular fovea fusion However, there are peripheral fusion and rough stereoscopic view (it is reported that the near stereoscopic sharpness is 67300, and the far view is 120240).
Examine
Small degree squint check
No special laboratory tests are required.
The squint is small because the oblique angle of view is small, so the strabismus is not obvious; and because the inhibitory dark spots in the macular area are extremely small, the general occlusion method or the same vision machine can not find the strabismus and the abnormal retina corresponding, and the 4 prism test must be applied. The Worth four-lamp test and the Bagolini linear lens test can detect the central dark spot and the abnormal retina in the binocular field of view to confirm the diagnosis.
1.4Triangular test method
4 Put it outward in front of any one, and look at the light source 5m away. Because of the action of the prism, the object image falls on the temporal retina. At this time, the eye is re-focusing on the fovea, and must be turned inside. At this moment, another The eye must be turned outwards, that is, in the same direction, so that the object image falls in the fovea of the two eyes at the same time. When there is a slight degree of strabismus and amblyopia, if the bottom of the 4 prism is placed outward in front of the healthy eye, the eye is turned inside. According to the Hering rule, if the nerve impulses received by the two eyes are equal, the affected eye will inevitably turn outward. On the contrary, if the 4 prism is placed outward in front of the affected eye, the gaze point on the retina moves from the side center gaze point to the center. The concave area, and the central area is a suppressive dark spot, so the affected eye does not rotate, and the healthy eye does not rotate, which proves that the affected eye is a small degree strabismus, and the 4 triangular prism can be used to measure the dark spot size, the method is gradually increase The degree of prism until the patient complains of double vision or from no movement to movement, the bottom-out prism is increased by the bottom edge, and the bottom-inward prism is used to measure the dark side of the nose. The value of the triangular prism with large squint is the squint. The statistical value can be used as the basis for the diagnosis of micro-inner or slight exotropia. If there is a slight degree of external squint, the 4 triangular prism in-situ test is performed.
2.Worth four-lamp test
Far from the four-lamp device, the projection is 1.25° at 6m, which can be used to check the foveal function of the macula. Nearly four-lamp device can be used to project 6° at 1/3m, which can be used to check the retinal function around the macula. The function can see 4 lights, which are 3 green 1 red or 2 green 2 red, but in the case of a slight degree of squint, if the patient's fovea has a dark spot of 1.25°, then the eye can be detected by using four lights. It can only see 2 red lights or 3 green lights; while looking at the near 4 lights, because the projected area of the lamp point on the retina of the affected eye is larger than the central blind spot, 4 lights can still be seen, which proves that there is peripheral fusion in the eye. .
3.Bagolini linear mirror test
Bagolini striated glasses test (Bagolini striated glasses test) means that the linear lens is engraved with thin lines (the line on the right lens is 45°, and the line on the left lens is 135°). Under normal circumstances, wear it. When the mirror looks at the front point light source, two intersecting rays perpendicular to each other can be seen. The light spot is located at the intersection of the intersecting lines. If only one light beam is seen, the eye with no bright line can be suppressed. Seen in a large degree of squint, if there is a bright line at the intersection of the two bright lines, it is interrupted around the spot, indicating that the eye has a central suppression. This can be seen in a slight degree of squint. If you see 2 spots, each spot When there is a bright line passing through, it is double vision, indicating that the perception coordination of both eyes is weak.
4. Same vision inspection method
With the center-type 1° fusion picture, the examinee does not see the mouse's ear or tail, indicating that there is a dark spot.
Diagnosis
Minor degree strabismus diagnosis
The diagnosis can be confirmed based on the results of the clinical examination.
