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Treatment of Myopia

The myopia can be corrected by divergent contact or combined spheroprizmatic lenses. The conservative treatment includes:

1. Removel of accommodation spasm.

2. Special exercises, medicines, electro- and phonophoresis with aloe, vitamins, phosphen electrostimulation, laserstimulation for strengthening of ciliar muscle tonus.

3. Spectacles with positive glasses for reading.

4. Common health therapy: vitamin and tissue therapy, mas­sage of colar zone, acupuncture.

If myopia makes progress the operative treatment is necessary for strengthening of sclera (retrosclerosealing, scleroplasty). The technique, elaborated at our department with strengthening not only posterior, but also anterior part of the sclera is especially effective.

In case of non-progressive myopia it is possible to make the keratomileusis, the extraction of transparent lens. Laser correction is wide-spread.

The Kinds of Myopia Prophilaxis

1. Harmonic physical development of the child.

2. Fulfilment of the sanitary-hygienic conditions of illumination and organization of working place of schoolchildren.

3. Picking out of the risk groups among children with reduced volume of accommodation, who have myopia in their family.

4. All myopes should be registered in the health center. The pa­tients with weak or mean degree of myopia mast be watched not less, than twice a year, with high degree — not less than 3 times a year with carrying out of corresponding courses of treatment.

5. Anisometropia is the unequal refraction of both eyes. It is ac­companied by various sizes of the retinal images — aniseikonia. Usually the image of one eye is suppressed in the cortex of brain, that leads to development of refractive amblyopia. It is possible to correct the anisometropia up to 2.0 D (for children — maximum 4.0 D) by the help of eyeglasses with the difference of refraction more than 2.0 D wearing of isoiconic spectacles, contact correc­tion or surgical treatment (refractive keratoplasty, keratotomia, excimer laser) is recommended.

6. Astigmatism — is an anomaly of refraction, at which there are different kinds of refraction of different degrees of the same refrac­tion at various meridians of the same eye. Astigmatism more of­ten arises owing to incorrect curvature of mean part of the cor­nea, more rare due to lens.

7. There are regular and irregular astigmatism. The regular astig­matism is usually the inherent astigmatism, at which the refract­ing force within the limits of one meridian is identical, at irregular one — each meridian at various parts refracts light with different force. At irregular astigmatism two meridians are picked out: with the greatest and the least refraction (main meridians). They are dis­posed perpendicularly to each other. The astigmatism in 0.5 D is characteristic almost of all eyes; it has not an influence on sharp­ness of vision, it is considered as physiological and does not re­quire the correction. If the refraction on vertical meridian is more, than on horizontal, it is the direct astigmatism. At indirect astigma­tism the refraction is more on horizontal meridian. This form even in case of weak degree considerably reduces the sharpness of vision. The astigmatism at which the main meridian passes between hori­zontal and vertical is named as astigmatism with oblique axes.



8. Simple myopic or hypermetropic astigmatism — there is ernmetropia in one meridian and myopia or hypermetropia —- in the opposite one.

9. Complex myopic astigmatism — there is myopia of some degree in one meridian and myopia of the other degree — in the opposite one.

10.Complex hypermetropia astigmatism — there is hypermetropia in both meridians but of various degree.

11.Mixed astigmatism — there is myopia in one meridian and hy­permetropia — in the opposite one.

 

Correction of astigmatism. Astigmatism considerably reduces sharpness of vision, complicates the work at a close distance and caus­es the asthenopic phenomena, chronic blepharoconjunctivitis and am­blyopia. The correction is possible by cylinder lenses. They are char­acterized by that rays, which pass in the plane parallel to axis of lens, do not refract, but the rays, which go in the plane, perpendicular axis, refract, i.e. the glass is established so, that the axis of the cylinder is perpendicular to the meridian, which is necessary to correct.

At high degrees of astigmatism which are not corrected by op­tic glasses, it is necessary the correction by solid contact lenses or refractive operations on the cornea.


Date: 2015-01-11; view: 457


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