Laser vision correction surgery and control of myopia progression in young adults

The World Health Organization has recently identified myopia as one of the five leading causes of blindness worldwide with rapidly increasing prevalence, projected to reach 50% of the world's population by 2050. Increasing level of myopia is associated with a higher risk of potentially blinding eye pathologies (macular degeneration, glaucoma, cataract, and retinal detachment), which is also leading to increased healthcare costs. The current knowledge suggests that image in eye's peripheral retina when optically corrected with common glasses/contact lenses, seems to lead to progression of myopia, due to "hyperopic peripheral defocus". On the contrary, optical inversion of the hyperopic peripheral defocus, to a negative one, seems to have the opposite effect and could slow down myopia progression, as confirmed by animal studies. Clinical studies with use of soft contact lenses with multifocal optics (MCLs) that produce myopic peripheral defocus, have registered a significant slow-down in myopia in children. Laser vision correction (LVC), a well-proven treatment to optically correct myopia by reshaping mostly the central cornea, leads to induction of the myopic peripheral defocus, similar to the effect of MCLs. Hence, it may be expected that the optical change induced by LVC would also act as a stimulus for slowing myopia progression. Our main objective, showing that the LVC slows myopia progression in young adults, will be proved by a historical longitudinal matched controlled study comparing myopia progression five years after myopic LVC with progression in a non-treated matched myopic population. The projects objectives to prove that the LVC is causing myopic peripheral defocus in retina comparable to the one achieved by MCLs (that are currently used for control of myopia progression in children), will be achieved by performing two prospective clinical trials.

Myopia is a major public health concern affecting about 30% of worldwide population, with rapidly increasing prevalence, projected to reach 50% globally by 2050. The increasing level of myopia is associated with a higher risk of potentially blinding eye pathologies (macular degeneration, glaucoma, cataract, and retinal detachment), which is also leading to increased healthcare costs. The World Health Organization has recently identified myopia as one of the five leading causes of blindness worldwide and The World Council of Optometry has recently urged eye care professionals to prioritise prevention of myopia progression. Current knowledge suggests that the positive peripheral defocusing of the retinal image, normally present in myopic eyes corrected with common glasses/contact lenses, seems to lead to progression of myopia. However, optical inversion of the positive peripheral defocus, to a negative one, could slow down myopia progression, as confirmed by both animal studies and clinical studies with use of multizonal soft contact lenses (MCLs) in children. Laser vision correction (LVC), a well-proven treatment to optically correct myopia by reshaping mostly the central cornea, leads to induction of the negative peripheral retinal defocus, similar to the effect of MCLs. Hence, it may be expected that the optical change induced by LVC would also act as a stimulus for slowing myopia progression. The main objective, showing that the LVC slows myopia progression in young adults, will be proved by a historical longitudinal matched controlled study comparing myopia progression five years after myopic LVC with progression in a non-treated matched myopic population. The projects objectives to prove that the LVC is causing negative peripheral defocus in retina comparable to the one achieved by MCLs (that are currently used for control of myopia progression in children), will be achieved by performing two prospective clinical trials.