Philippine Daily Inquirer / 05:02 AM July 06, 2023
Three years ago, I wrote an article, “Myopia: The other pandemic,” (Commentary, 6/21/20) discussing the rapid rise of myopia in the world. While COVID-19 appears to be receding in our rearview mirrors, the increase in the incidence of myopia continues unabated and is projected to affect 4.8 billion people, or about half the world’s population, by 2050. This is an update.
While regular eyeglasses and contact lenses have been the traditional tools to address myopia, recent research points to these interventions actually having the reverse effect, that is, they may actually worsen this vision abnormality. One such study conducted by professor Earl Smith, former dean of the College of Optometry of the University of Houston, indicates that regular glasses and contact lenses do not address a crucial factor in the onset of myopia: the peripheral visual field. This is the part of the eye that accepts light mostly from the side. He concluded that light coming to the periphery, or side of the eye, rather than those coming from the center, has a more impactful influence on the development of the eye, or the overall shape or length of the eyeball, in children. The cornea is the main focusing mechanism of the eye. Regular eyeglasses and contact lenses focus light in the center, rather than the sides, of the eye. Doing so actually elongates the eyeball and in the process aggravates the myopia condition.
Attention should now shift, he says, to efforts to find alternatives to regular glasses and contact lenses so as to not induce further elongation of the eyeball. One such alternative intervention mode is orthokeratology, or wearing special contact lenses at night during sleep. These special lenses reshape the cornea and have been proven to be an effective myopia management option. Special contact lenses, such as central distance soft contact lenses, have also proven effective. Lenses such as the DIMS Defocus, a spectacle lens design, incorporated multiple segments. Research and studies also show that these lenses slow down myopia by 60 percent in comparison to regular glasses.
But prevention remains crucial in addressing the surge of myopia cases worldwide. Getting children to go outside and get more sun continues to be a recommended preventive measure. Limiting use by children of devices such as smartphones and computers is another.
Carmen Abesamis-Dichoso, OD