July 16, 2012 The size of a refractive error in the progressive myopia is from -7 D to more than -30 D, with an error that increases gradually, that is, it progresses throughout life due to the continued growth of the eyeball.
Progressive myopia is an inherited degenerative disease that affects almost all parts of the eye. It causes enlargement of the whole eyeball, corneal enlargement, posterior sclera stafiloma, changes in trabeculum, a higher incidence of cataracts, degenerative changes in the vitreous, and degeneration of the retina and choroid. Myopic degenerations of the chorioretina and vitreous highly increase the frequency of the ablation of the retina.
MYOPIC DEGENERATION OF THE RETINA AND CHOROID
The progressive myopia on the back half of eye background appears a characteristic myopic degeneration of chorioretina: round areas of atrophy, depigmentation and hyperpigmentation, with consequent reduction in visual acuity. Optical disc is pale, and next to its temporal part occurs the atrophy of the choroid (myopic crescent).
Treatment:
In some ophthalmic centers a scleroplastics is performed, which is a reinforcement of the sclera with autotransplant fascia late or homotransplant of the sclera in order to stop the growth of the eye, but without effective results.
Orthokeratology is a procedure of remodeling of the surface of the retina by a programmed wearing of hard contact lenses. A number of contact lenses serve for this purpose; i.e. lenses with reverse geometry that gradually reduce the curvature of the cornea. Each lens is worn for several days, until it reshapes the surface of the cornea, then it is replaced with the next lens of different dimensions, which acts as an even stronger “mold” for the cornea. Orthokeratology has a temporary effect – as soon as the patient stops wearing lenses, in a few days his eyes take on the earlier diopter strength. In addition, the process with high myopia is expensive because of the large number of contact lenses of different sizes that make an orthokeratological program. However, this procedure has a particular application for small myopias. Then contact lenses with reverse geometry are worn overnight, which allows the patient to be without lenses during the day.
Refractive surgery can reduce the fracture strength of the cornea up to -20 diopters.
Unfortunately, none of the methods known today cannot halt the progression of progressive myopia, especially not of chorioretinal changes which are the heaviest element of this disease.