Myopia control study demonstrates 4-year results of Diffusion Optics Technology

The results of CYPRESS Parts 1 and 2 support the theory that modulating retinal contrast can slow the progression of myopia, investigators said. Image credit: ©ihorvsn – stock.adobe.com

The results of a recent study showed that Diffusion Optics Technology (DOT) 0.2 spectacle lenses (SightGlass Vision) are safe and effective for reducing myopia progression in young children. The lenses showed an additional benefit in the 4^th year of wear. The study results supported the hypothesis that a mild reduction in retinal contrast can slow myopia progression in young children,¹ according to senior author James S. Wolffsohn, MB, PhD, who is professor of optometry, College of Health and Life Sciences, Aston University, Birmingham, UK.

Because myopia has become a worldwide epidemic, numerous researchers have been searching for ways to stem the progression of the disease. The CYPRESS Study is one such effort.

High myopia is associated with an increased risk of sight-threatening ocular pathology.^2,3 Slowing myopia progression is likely to improve long-term ocular health and visual outcomes,⁴ the investigators commented.

Contrast modulation

Myopia control optical interventions are designed to manipulate the key visual signals, defocus and contrast, that regulate eye growth and refractive state.^5,6 Abnormally high retinal contrast signaling has been reported to be associated with progressive myopia.⁷ Mild reductions in retinal contrast via the novel DOT spectacle lenses have shown promise in slowing eye growth and myopia progression in a 12-month interim analysis in the randomised, controlled, multicentre CYPRESS trial.

In the study under discussion, the investigators evaluated how well the DOT lenses controlled myopia in children over a 4-year time frame.

CYPRESS Part 1 (NCT03623074) was a 3-year multicentre, randomised, controlled, double-masked trial during which two DOT designs (test 1 and test 2) were compared; a standard single-vision control lens served as a control. Once the children completed CYPRESS Part 1, they could be included in Part 2 (NCT04947735), which tested the lenses for an additional 1 year. During that additional year, 35 patients from Part 1 and 42 controls continued to wear the same lenses (test 1), and 21 children in the test 2 group were crossed over to the test 1 lenses. The primary endpoints were the changes in axial length (AL) and cycloplegic spherical equivalent refraction (cSER) compared with the baseline values, the investigators explained.

The results showed that the test 1 spectacle lenses “demonstrated superiority to the control in both primary endpoints: with a difference between means (test 1−control) of −0.13 mm for AL (P = .018) and 0.33 diopter (D) for cSER (P = .008) in Part 1 and −0.05 mm for AL (P = .038) and 0.13 D for cSER (P = .043) in Part 2.”

They also mentioned that when they compared the treatment effects in Parts 1 and 2, they believe that the COVID-19 public health restrictions may have negatively impacted treatment efficacy in study years 2 and 3.

Dr Wolffsohn and colleagues concluded, “Contrast modulation is a novel mechanism of action to slow the progression of myopia. The results of CYPRESS Parts 1 and 2 support the theory that modulating retinal contrast can slow the progression of myopia. DOT 0.2 spectacle lenses are a safe and efficacious myopia management treatment for children from age 6 and are a suitable early treatment option for myopic children.”

References

1. Laughton D, Hill JD, Marcella McPartland, et al. Control of myopia using diffusion optics spectacle lenses: 4-year results of a multicentre randomised controlled, efficacy and safety study (CYPRESS). BMJ Open Ophthalmol. 2024;9:e001790

2. Verkicharla PK, Ohno-Matsui K, Saw SM, et al. Current and predicted demographics of high myopia and an update of its associated pathological changes. Ophthalmic Physiol Opt. 2015;35:465–75; doi:10.1111/opo.12238

3. Jones D, Luensmann D. The prevalence and impact of high myopia. Eye Contact Lens. 2012; 38:188–96; doi:10.1097/ICL.0b013e31824ccbc3

4. Bullimore MA, Brennan NA. Myopia control: why each diopter matters. Optom Vis Sci. 2019;96:463–5; doi:10.1097/OPX.0000000000001367

5. Troilo D, Smith EL, Nickla DL, et al. IMI - report on experimental models of emmetropization and myopia. Invest Ophthalmol Vis Sci. 2019;60:M31–88; doi:10.1167/iovs.18-25967

6. Smith EL, Xie P. Research updates on a role for retinal contrast in myopia control. Chin J Ophthalmol. 2023;59:488–91; doi:10.3760/cma.j.cn112142-20230207-00042

7. Neitz M, Wagner-Schuman M, Rowlan JS, et al. Insight from OPN1LW gene haplotypes into the cause and prevention of myopia. Genes (Basel). 2022;13; doi:10.3390/genes13060942