Terapia refractivă: istoric şi perspective

Abstract

Background: Myopia has been labeled as one of the most commonly encountered ocular disorders and its prevalence is increasing worldwide. The percentage of myopia varies from country to country starting from 25% in the United States to 90% in Asian countries. This has caused a massive concern, which raised great interest in methods of treatment and prevention of myopia, one of which is orthokeratology. Over more than two decades, orthokeratology had no widespread acceptance, partly because of the scientific community argued that the use of hard PolyMethylMethAcrylate lenses increase the risk of central cornea impairment. Optometry and Ophthalmology did not accept the method as from lack of clinical evidence that orthokeratology does not interfere with the structure and function of the cornea. The fact that only orthokeratology was able to evolve, demonstrate and monitor corneal topographic changes, limited the number of cases for the purpose of scientific study. But the advent of corneal topography allowed a more scientific approach to this procedure. Conclusions: The mechanism of refractive therapy to halt the progression of myopia is based on the formation of a bifocal optical zone that transforms the hyperopic defocus into a weak myopic one. According to statistics significant risk of developing microbial keratitis when wearing rigid gas-permeable lens is 4 times lower than in the case of soft lenses and 20 times smaller than soft lenses for extended wear. Patients who have undergo neorthokeratological correction presented neither at near nor at distance vision impairment, had no diurnal fluctuations of visual acuity or habitual activity limitation, which shows a positive impact of therapy on quality of life.