Strabismus( heterotrophy, strabismus) - Causes, symptoms and treatment. MF.

Strabismus( heterotrophy, strabismus) is a visible manifestation of the pathology of the oculomotor apparatus, characterized by an incorrect nonparallel position of the cornea.

Strabismus

Strabismus causes

Causes of strabismus:

- ocular( congenital maldevelopment of oculomotor muscles, tumors and eye trauma, refractive errors, especially anisometropia, amblyopia),
- nerve( paralysis and muscle paresis, multiple sclerosis),
- endocrinethyrotoxicosis),
- infectious( influenza, measles),
- mental( neuroses, fright)

Strabismus is congenital( manifested with a newborn) and acquired.

Symptoms of heterotrophy

Seemingly squinting

Newborn babies up to 6 months of age are unable to fix objects, so the eyes "swim".Similarly, with a certain structure of the skull with a broad bridge of nose, it may seem that there is heterotropy. This is the norm( the so-called imaginary, or apparent strabismus).

Concealed strabismus

The latent strabismus appears due to the difference in muscle strength on both sides. When viewed with both eyes, compensatory muscular mechanisms are activated and heterotrophy is not noticeable. But when one eye is turned off from the visual act, for example, by closing it with his hand, the second one deviates to the side. Depending on the side, the

esophoreia ( inside), exophoria ( outward), hypophoria ( down), hyperforia ( up) are isolated.

Treatment of latent strabismus is required only in cases of asthenopia( visual fatigue).Assign correction of refractive errors.

True Strabismus

True strabismus can be friendly and paralytic. At the same time, one or both of the eyes deviate to the side.

Friendly strabismus occurs mainly in children, accompanied by a violation of binocular vision. Depending on where the eye deviates, distinguish:

- esotropia( convergent)
- exotrophy( divergent)
- vertical( up-hypertropy, down-hypotrophy)
- combined strabismus

There is a monolateral( mowing only one eye) and alternating(both eyes alternately deviate) strabismus.

Depending on the involvement in accommodation, strabism happens:

- accommodative. With adequate correction of ametropia, the position of the eyes becomes normal.
- non-accommodation. Correction is effective only after surgical treatment.
- partially-accommodative. Wearing glasses or contact lenses does not completely eliminate the deviation of one or two eyes.

Depending on the magnitude of the deviation, the strabismus is:

- very small( up to 5 degrees)
- small( 6-10 degrees)
- average( 11-20 degrees)
- pronounced( 21-35 degrees)
-(more than 36 degrees)

Paralytic strabismus occurs due to paresis or paralysis of the oculomotor muscles, due to trauma, tumors, infectious or neurological diseases. Symptoms: limitation or complete immobility of the eye, doubling, compensatory turn of the head. The main method of treatment is surgical( muscle plastic)

Paralytic strabismus

A patient with strabismus can make the following complaints: deviation of one or both eyes to the side, double vision, decreased visual acuity, asthenopia( visual fatigue), and also related to the underlying disease that caused strabismus.

Diagnosis with strabismus

For the diagnosis, the following research methods will be needed:

- visual acuity determination with correction and without.
- perimeter.
- the volume of movements of the eyeballs can be reduced, and when there is no muscle paralysis. To do this, ask to monitor any object( for example, the handle, the handle of the ophthalmoscope) while moving up, down and to the sides.
- determination of refraction in the state of mydriasis with the help of a skiascopy or refractometer.
- four-point color-test - examine the nature of vision( binocular, monocular or simultaneous).To do this, wear special glasses and ask to look at the screen with multi-colored dots. Depending on how many circles and what color the patient sees, establish the type of vision

Four-point color test

- angle of strabismus according to Hirschberg. With the help of an indirect ophthalmoscope, the position of the reflex on the cornea is viewed.

The angle of strabismus according to Hirschberg

- on sinoptophora determine the presence and degree of strabismus( in degrees).At the same time, images from each eye are separated, and one pattern is normally obtained.
- biomicroscopy
- ophthalmoscopy and examination of the fundus with the Goldman lens( pathology of the vitreous and retina)
- ultrasound of the eye, including the determination of the
- computed tomography of the orbit to exclude the organic pathology of the muscles or nerves
- consultation of the neurologist, pediatrician and endocrinologistif necessary

Treatment of strabismus

Treatment should be started as early as possible to prevent the development of complications such as amblyopia.

First of all, eliminate the causes that caused strabismus, if any. Then the main goal is to achieve central fixation, eliminate strabismus or make it alternating( alternating).

First, an adequate correction of vision is selected depending on the type and degree of ametropia. In this case, the normal position of the eyes is possible, if the accommodation is accommodative.

Then the methods of pleoptics are used to treat amblyopia - "cut off" from the visual process without a mowing eye. To do this, set the opaque screen( gluing), closing the best seeing eye for a period, set individually. At night, the screen is cleaned. Thus, the mowing eye becomes fixative.

Ocular and contact correction is prescribed from 6-9 months of age( before this the child does not fix the object and the eyes can "swim").

Special devices are used to increase visual acuity and fix the central fixation( acomotor, amblyopanorama, maculostimulator).

Also in amblyopia, the method of penization is used, when atropine is ordered in the best eye, creating artificially anisometropia. In this case, the mowing eye also becomes fixative.

After achieving the required visual acuity( 0,4-0,5) begin orthoptic treatment. With this method, the ability of the eyes to fuse, for example, on synoptophor, binaryimeter, is developed. Fields of vision are divided and each picture has its own picture, together they form a single object( a mouse with a tail and without ears + a mouse with ears and without a tail = a whole mouse).

Methods of diplopty with a large angle of strabismus( more than 10 degrees) are used only after surgical treatment. Their goal is to establish and fix normal binocular vision. With the help of prisms, first create an artificial diplopia, and then induce to bifixation. In addition, spherical prismatic lenses of varying strength are alternately attached to the eyes. Also use apparatus( Diplom-P) and computer programs( "Contour", "EYE").

Physiotherapy works on weakened muscles. Apply electromyostimulation and darsonvalization of the eye area.

The magnitude of the angle of strabismus determines the tactics of treatment. If the angle of strabism is initially more than 15 degrees, surgical treatment is most likely inevitable. If the angle of strabismus is 20 degrees or more, the operation is recommended immediately after adaptation to glasses and gluing. At small angles of strabismus - less than 10 degrees, often limited only by hardware treatment. In any case, patient management presupposes a logical sequence of therapeutic actions to restore binocular vision.

Conservative and hardware treatment in any case need to pass at least 2 times a year.

Surgical treatment of strabismus

If the position of the eye is still asymmetrical, a surgical technique is used. Principles of surgical treatment:

- operate in the absence of the effect of prolonged wearing glasses or lenses( 1-2 years)
- the optimal age for the operation is 4-5 years. At a congenital or large angle of strabismus - 2-3 years
- at an angle of strabismus more than 30 degrees, operate in 2 stages
- if it is necessary to operate both eyes, then observe the sequence, i.e.interval approximately six months.

Operations that increase muscle action include resection of the muscle( shortening), formation of a tendon or muscle fold and movement of the attachment site of the muscle anteriorly.

Operations that weaken the action of muscles: lengthening with the help of incisions, transferring the place of attachment to the back and plastic muscles or tendons.

Strabismus is a disease that needs to be treated as early as possible. Otherwise, it will lead to the development of amblyopia, at an older age will bother as a cosmetic defect. For some professions, binocular vision is necessary. Strabismus can be cured, only patience and a desire to recover.

Doctor ophthalmologist Letyuk T.Z.