Design: Executive bifocal with +2.00 Add and 3 base-in prism in the near zone of each lens.
The prismatic bifocal employed in the Myopilux Max lens is based on the research of Cheng et al 2008,1 where a combination of near adds and base-in prism amounts were tested, measuring the accommodative lag and exophoric shifts typically expected when applying a near add. The use of the base-in prism was designed to balance accommodation and vergence systems – not to reduce the response of either system. The concept of the prismatic bifocal was that there was, on average, no change induced to either lag or phoria once wearing the bifocal.
Myopia control mechanism
The presumed mechanism of could be considered as a combination of simultaneous defocus theory and accommodation lag theory. The former is the stronger contender - given that the prismatic bifocals were designed not to alter accommodation or vergence demand. Cheng et al didn't directly investigate this in their clinical trial2,3 but the large zone of ‘add’ in the inferior lens creates a relative peripheral myopic shift on the superior retina. One (unrelated) study found a relationship between the amount of relative peripheral myopia created by the inferior add zone and the myopia control effect of progressive addition spectacle lenses,4 indicating alignment with the simultaneous defocus theory.
The three-year clinical trial3 results found that children with a lower lag of accommodation (<1.01D at 33cm) got half of the refractive treatment effect from the bifocals (0.50D less final myopia) compared to the prismatic bifocals (0.99D less final myopia). The children with higher lags (1.01D or more) had a similar, 1.1D control effect over three years in both bifocal designs. In their discussion, Cheng et al3 state that "for children with high lags, reducing the accommodation lags with standard bifocals is adequate to control myopia progression."
Myopia control efficacy
A randomized clinical trial in Chinese Canadian children aged 8-13 years with progression of at least 0.50D in the prior year showed efficacy in both the bifocal and prismatic bifocal to slow axial and refractive myopia progression. See the scientific paper summary below.
The ideal childhood myope candidate in age and refraction for the Myopilux Max spectacle lens is not described by the manufacturers, but the participant characteristics in the clinical trial can be noted.
Peer reviewed science on Myopilux Max efficacy and safety
Cheng et al 2010. Randomized Trial of Effect of Bifocal and Prismatic Bifocal Spectacles on Myopic Progression: Two-Year Results. [link to paper abstract]
Chinese Canadian children (n=131) aged 8-13 years with myopia of at least -1.00D and myopia progression of at least 0.50D in the past year were randomized into single vision spectacles, +1.50D executive bifocals or +1.50D executive bifocals with 3 dioptres of base-in prism in the near segment of each lens. In two years, myopia progressed -1.55D/0.62mm in SV, -0.96D/0.41mm in bifocals and -0.70D/0.41mm in prismatic bifocals.
- Cheng et al 2014. Effect of Bifocal and Prismatic Bifocal Spectacles on Myopia Progression in Children: Three-Year Results of a Randomized Clinical Trial. [link to open access paper]
The participants in the Cheng et al 2010 study completed three years of wear (n=128). In three years, myopia progressed -2.06D/0.82mm in SV, -1.25D/0.57mm in bifocals and -1.01D/0.54mm in prismatic bifocals, representing a 40-50% refractive and 30-35% axial length myopia control effect of bifocals and prismatic bifocals respectively. The treatment effect was independent of near phoria status. Children with high lags of accommodation (1.01D or more) had a similar treatment effect with both bifocals while children with lower lags (<1.01D) had a greater treatment effect with prismatic bifocals (0.99D less final myopia) than bifocals (0.50D less final myopia).
Myopia Profile relevant blog posts
When To Prescribe Spectacles For Myopia Control
Spectacle Lenses For Myopia Control Part 1: Progressives, Bifocals And Binocular Vision
Myopia Profile clinical case studies on Myopilux and bifocals
Myopia Profile: Integrating myopia management into clinical practice. In this interview, Dr. Kate Gifford and Dr. Paul Gifford, Founders of Myopia Profile, share their success formula on integrating myopia management into clinical practice, tips on encouraging parents to take myopia more seriously and available resources for practitioners on myopia management. (February 2021)
International Myopia Institute and Essilor: Charting a Way Forward on Myopia Management. Monica Jong, Executive Director of the International Myopia Institute (IMI) and Gilles Le Saux, Senior Vice President, Research and Foresight, Essilor International, highlight the urgent need for myopia to be recognized as a global public health issue, discuss IMI and Essilor’s shared vision to address myopia together and lend their perspectives on how the IMI white papers can advance myopia research, education and management in the years to come. (February 2021)
Myopia and effective management solutions. In this Points De Vue online article, Vision Scientists at Essilor provide a general overview of myopia, describe available solutions for myopia management and discuss the relative efficacy for each solution. Finally, they focus on Myopilux®, the specific range of ophthalmic lenses which have been proven to effectively correct and control myopia progression in children. (December 2016)
Press releases on Essilor and myopia
- New results on Essilor Stellest™ lens to be presented at the annual meeting of the Association for Research in Vision and Ophthalmology (ARVO 2021) April 9, 2021
- CooperVision and Essilor Partner to Accelerate Access to SightGlass Vision Technology & Expand Myopia Management Category February 03, 2021
- Myopia Profile and Essilor join forces to tackle childhood myopia through education and awareness October 22, 2020
- With Stellest™ lens, Essilor reaffirms its leadership in myopia management October 5, 2020
- Essilor’s game-changing Stellest™ lens shown to slow down myopia progression in children by more than 60%, after one-year interim clinical trial September 28, 2020
- Cheng D, Schmid KL, Woo GC. The effect of positive-lens addition and base-in prism on accommodation accuracy and near horizontal phoria in Chinese myopic children. Ophthalmic Physiol Opt. 2008;28(3):225-237. (link)
- Cheng D, Schmid KL, Woo GC, Drobe B. Randomized Trial of Effect of Bifocal and Prismatic Bifocal Spectacles on Myopic Progression: Two-Year Results. Arch Ophthalmol. 2010;128:12-19. (link)
- Cheng D, Woo GC, Drobe B, Schmid KL. Effect of bifocal and prismatic bifocal spectacles on myopia progression in children: three-year results of a randomized clinical trial. JAMA Ophthalmol. 2014;132(3):258-264. (link)
- Berntsen DA, Barr CD, Mutti DO, Zadnik K. Peripheral defocus and myopia progression in myopic children randomly assigned to wear single vision and progressive addition lenses. Invest Ophthalmol Vis Sci. 2013;54(8):5761-5770. (link)