#Spectacle lenses trial
#Spectacle lenses plus

Likewise, positively aspherisized PALS with add power (+1.50 D) reduced myopia progression by 20 percent compared to single vision spectacle lenses. 12 These lenses also have an extended area of distance correction in the lower portion with no additional power.

#Spectacle lenses plus

11 These lenses have distance correction at the center for clear central vision with asymmetric design at the periphery incorporating continuous plus power for altering peripheral optics. 10 A reduction in myopic progression by 15.4 percent (spherical equivalent) and axial length elongation by 13.9 percent was observed with these lenses in this subgroup of participants.

#Spectacle lenses trial

Utilizing this strategy, the first-ever trial designed and tested three designs for peripheral defocus management but found only one design to provide reasonable control in a subgroup of children with parental myopia. 11 These strategies were based on inducing relative myopic defocus or reducing relative hyperopic defocus at the retinal periphery. 9įrom 2010 onward, there was a shift toward developing and testing myopia management devices that altered peripheral retinal defocus based on landmark studies that found that peripheral retina had a significant role in emmetropisation and refractive error development. 7 Executive bifocal spectacle lenses incorporated with base-in prism are available in many countries.

6, 8 An exception was executive bifocals with and without base-in prism that reduced myopic progression by approximately 51 percent (spherical equivalent) compared to single-vision spectacles. 1 2, 3 Bifocals and progressive addition lenses (PALs) were found effective only in few categories, such as those with a larger lag of accommodation 4-7 or faster myopia progression in myopia.

Although undercorrection was widely practiced, it was shown to increase myopia progression.

Up until 2010, the only options available to control myopia with spectacle-based strategies were progressive addition or bifocal spectacles. By Krupa Philip, PhD, Brien Holden Vision InstituteĪlthough 2020 is a year that many will consider as best forgotten or relegated to history, for spectacle-based myopia management strategies, it marks the end of a decade of rapid and significant improvements to slow myopia.