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Introduction Strabismus means that both eyes cannot look at the target at the same time. It is an extraocular muscle disease and can be divided into two categories: common strabismus and paralytic strabismus. Common strabismus is characterized by eye position biased to the temporal side, no movement disorder of the eyeball, and no recurrence as the main clinical features; paralytic strabismus has limited eye movement, diplopia, and systemic symptoms such as dizziness, nausea, and gait instability.

Cause

1. Regulation theory: The regulation of the eye and the collective action of the eye are interrelated, and certain adjustments bring the corresponding collection. Often due to the regulation - the set reflection is too strong, the role of the inner rectus muscles exceeds the tendency of the lateral rectus muscles, and forms a common esotropia. When the nearsighted eye is close to the target, it is used less or not, and the collective force is simultaneously weakened. Therefore, the tension of the inner rectus muscle is reduced, and a common exotropia is sometimes formed.

2. Binocular reflexology theory: binocular single vision is conditional reflex, which is achieved by means of fusion function, which is acquired. If the visual acuity of the two eyes is different during the formation of the conditioned reflex, and the visual sensation or dyskinesia of the eye obstructs the function of the binocular single vision, a state of separation of the eye position, that is, strabismus, is generated.

3. Anatomy: A certain extraocular muscle development or hypoplasia, abnormal extraocular muscle attachment points, eyelid development, abnormal fascia structure, etc., can lead to muscle imbalance and strabismus.

4. Genetics: Many people in the same family are clinically common with common strabismus, and strabismus may be related to genetic factors.

an examination

Related inspection

Eye and sacral area CT examination of the eyeball and eyelid ultrasound examination of the brain ultrasound examination ophthalmoscopy corneal mapping

The following is a routine inspection of strabismus:

1. Inspection of binocular vision function

(1) The three-level situation in which the same vision machine is used in the country to check the binocular vision function.

(2) Quantitative measurement of the stereoscopic vision function, and the stereoscopic sharpness is measured by the stereoscopic quantitative picture of the same machine or the random point stereogram of the Young's.

2. Refractive examination

Atropine paralyzed ciliary muscle optometry: to understand whether there is amblyopia and the relationship between strabismus and refraction.

3. Determination of eye position and oblique angle

Determine which type of strabismus it is. The size of the oblique viewing angle must be checked for surgical design.

4. Eye movement check

Determine the function of the extraocular muscles and see if the eye movements are in place.

5. Is there a compensatory head position?

Help diagnose which extraocular muscle paralysis.

6. Determine the examination of the paralysis muscles

Check the movement function of the eyeball, the gaze angle of each eye, and the gaze angle of each eye in each direction, using the red lens test or

Checks such as the Hess screen method can help determine.

7. Pull test

(1) Estimate postoperative diplopia and patient tolerance after pulling the eyeball to the ortho position before surgery.

(2) Passive pull test can be used to understand whether there is mechanical contraction of the extraocular muscles or muscle spasm.

(3) Active contraction test to understand the function of the muscle.

8. Obscure inspection

Quantitative determination was made using a hidden inclinometer. Detection of collection points: Helps diagnose muscle fatigue.

9. Regulatory set/adjustment (AC/A) ratio determination

Help determine the relationship between strabismus and adjustment and collection.

Differential diagnosis

1. False internal oblique: internal epithelium, wide nasal bridge, and poor nasal bridge.

2, paralytic strabismus identification points: there are diplopia symptoms, dizziness, gait instability; eye movement is restricted, out of the modern head position. When the eyes are gazing, the oblique viewing angles are not equal, and when the paralyzed eyes are gazing, the oblique angle becomes larger, that is, the second oblique viewing angle > the first oblique angle. For example: right eye paralytic exotropia double vision.

3, the clinical characteristics of accommodative esotropia: age of onset: more than 2-3 years old, often have incentives (high fever); uncorrected ametropia anterior oblique angle change, intermittent change to constant, wearing foot hyperopia to correct intraocular strabismus Disappeared, no surgery required; often with amblyopia; may have a family history.

4. When one eye is gazing, the other eye is skewed, and the nasal side is a common internal oblique, and the lateral side is a common external oblique.

5, eye movements are barrier-free, there is no significant difference in strabismus in all directions.

6. The second oblique viewing angle is equal to the first oblique viewing angle.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.