The SightGlass Vision DOT™ spectacles lens IMC 2024 showcase

The International Myopia Conference (IMC) 2024 brought together leading experts in optometry and ophthalmology to discuss the latest advancements and innovations in myopia research. SightGlass Vision and partners presented 9 abstracts, 3 of which were selected as podium presentations and 6 presented as posters. Here, we summarize the abstracts which look at efficacy, safety and performance of Diffusion Optics Technology™ (DOT™) spectacle lenses, changes in ocular structures that may occur with myopia control spectacle lenses and how near work affects myopia.

Authors: Zhi Chen,¹ Lucill Wang,² Deborah Laughton,² Jennifer S Hill,² Marcella McParland² Tian Han, ¹ Yishan Qian ¹

1. Shanghai Eye and ENT Hospital , Shanghai, China
2. SightGlass Vision, Inc, Dallas, TX, USA

This study assessed the safety and effectiveness of contrast modulation (Diffusion Optics Technology™, DOT™) spectacle lenses in managing myopia progression among Chinese children, following positive outcomes in the North American CYPRESS trial. In this randomized controlled trial, data from 186 participants aged 6 to 13 years was analyzed after 6 months of wear. Children wearing DOT™ spectacle lenses remained stable and experienced significantly less axial length growth (0.01 mm) and slower refractive error progression (0.04 D) compared to those using standard single-vision lenses (0.19 mm, -0.35 D). Visual acuity was excellent and no adverse events related to device use was noted. These results support the myopia control efficacy, safety and performance of DOT™ spectacle lenses, and affirms their broader applicability as an effective intervention across different ethnicities. The findings from this trial enable a comparison of the performance of DOT™ lenses with other defocus-based myopia control spectacle lenses that were also tested in all-Asian cohorts. At the 6-month point, DOT™ lenses demonstrate particularly promising outcomes.

Purpose: It has been well-established that manipulation of retinal image quality with optical defocus or contrast modulation can change the course of refractive development. A recent 4-year clinical trial (CYPRESS) demonstrated excellent safety and myopia control efficacy of contrast modulation spectacle lenses (Diffusion Optics Technology™, DOT™) with North American children. The purpose of this research was to evaluate the safety and efficacy of DOT™ spectacle lenses in a Chinese population. 

Methods: One hundred and ninety children aged 6 to 13 years were enrolled in a 2-year randomised controlled clinical trial across 5 Chinese hospital sites (NCT05562622). Data from 186 children who had completed the 6-month visit were analysed. Participants were dispensed DOT™ spectacle lenses or standard single-vision Control spectacle lenses in a 2:1 ratio. Axial length (AL) and cycloplegic spherical equivalent refraction (cSER) were measured at baseline and after 6 months of wear. Distance and near visual acuities (VA) and adverse events were also monitored at each visit.

Results: Participants’ mean age was 9.6 ± 1.8 years; male n=90, 48%. After 6 months of Control lens wear (n=58), mean changes ± SE in AL and cSER were 0.19 ± 0.02 mm (95%CI: [0.11, 0.26], p <0.0001) and -0.35 ± 0.05 D (95%CI: [-0.52, -0.26], p<0.0001). No significant change in AL or cSER was observed within the DOT™ lens group (n=128): mean changes ± SE in AL and cSER were 0.01 ± 0.01 mm (95%CI: [-0.01, 0.04], p=0. 306) and 0.04 ± 0.04 D (95%CI: [-0.03, 0.11], p=0.250). The unadjusted mean differences (DOT™–Control) in the changes from baseline were clinically and statistically significant for AL (0.18 mm, p<0.0001) and cSER (0.39 D, p<0.0001). Binocular distance logMAR VA were -0.02±0.07 for Control and -0.06±0.09 for DOT™; near VA were -0.01±0.10 for Control and 0.00±0.17 for DOT™. No significant device related serious adverse events have been reported to date.  

Conclusions: Interim results from this ongoing clinical trial demonstrate the safety and myopia control efficacy of DOT™ spectacle lenses, supporting the hypothesis that modulating retinal contrast can slow myopia progression in children from Chinese populations.

Authors: Deborah Laughton,¹ Jennifer S Hill, ¹ Marcella McParland¹

1. SightGlass Vision, Inc, Dallas, TX, USA

In a small subset of children in multiple myopia control trials, axial length (AL) has been noted to regress or shorten.^1-4 This phenomenon has been attributed to choroidal thickening that occurs in response to defocus,⁵ which is thought to create a shift in the position of the retina, thus reducing axial length.¹ This study explored the occurrence of AL reduction in myopic Chinese children using DOT™ spectacle lenses and its potential association with various factors. In a randomized controlled trial involving 186 children aged 6 to 13, after 6 months of lens wear, 49% of children in the DOT™ group showed AL reduction (mean: -0.11 mm), compared to just 5% in the Control group (mean: -0.04 mm). AL elongation was observed in 51% of the DOT™ group and 95% of the Control group. A strong correlation was found between changes in AL and refractive error (cSER), though no other significant predictors were found. Overall, these findings suggest that short-term wear of DOT™ spectacle lenses halts myopia progression, on average. Further data is required to evaluate whether response to treatment after 6 months may help practitioners to identify treatment responders, which could help inform their future management plan for an individual child.

Purpose: Multiple clinical trials have observed a small proportion of children undergo an initial reduction in axial length with defocus-based myopia control treatment, which has primarily been attributed to choroidal thickening. The purpose of this research was to explore the incidence of axial length reduction with contrast modulation spectacle lenses (Diffusion Optics Technology™, DOT™), and to investigate interaction with other variables. 

Methods: One hundred and eighty-six Chinese children aged 6 to 13 years with myopia from -0.75 D to -5.00 D were enrolled in a 2-year randomised controlled clinical trial across 5 sites (NCT05562622). The children were allocated to wear either DOT™ spectacle lenses or standard single vision Control lenses in a 2:1 ratio. Axial Length (AL) and cycloplegic Spherical Equivalent Refraction (cSER) were measured at baseline and after 6 months of wear. The DOT™ and Control groups were subdivided into two groups based on AL progression after 6-months of study lens wear: AL reduction (<0 mm change) or AL elongation (>0 mm change). The relationships between change in AL and change in cSER, baseline AL, baseline cSER, age, gender and previous lens wear were explored.

Results: After 6 months of wear, AL reduction was observed in 5% of the Control group (n=3, mean AL change ± SD: -0.04 ± 0.02 mm) and 49% of the DOT™ lens group (n=63, mean AL change: -0.11 ± 0.09 mm). AL elongation was observed in 95% of the Control group (n=55, mean AL change: 0.20 ± 0.12 mm) and 51% of the DOT™ lens group (n=65, mean AL change: 0.13 ± 0.11 mm). There was a significant association between lens group and AL change (Fisher’s exact test, p<0.001). Change in AL significantly correlated with change in cSER (R²=0.584, p<0.001). No significant relationships were observed between change in AL and the other variables investigated.

Conclusion: Almost half of the DOT™ lens group experienced a reduction in AL after 6 months of wear. The magnitude of the observed AL reduction implicates remodeling of multiple ocular structures. Further longitudinal follow-up is required to determine whether initial AL changes can predict the myopia control efficacy of a treatment for an individual child. 

Authors: Jennifer S. Hill¹, Deborah Laughton¹, Marcella McParland¹, Graeme Young², Chris Hunt²

1. SightGlass Vision
2. Visioncare Research, Ltd.

This study examined myopia progression in children after discontinuing DOT™ spectacle lenses following 4 years of wear, focusing on the potential for a rebound effect. A total of 54 children (mean age 13.54 years) participated, with 32 from the DOT™ group switching to single-vision lenses and 22 remaining in the control group. After 6 months, the former DOT™ group showed a mean myopia progression of -0.12 ± 0.23 D, while the control group showed -0.16 ± 0.19 D. Axial length increased by 0.11 ± 0.06 mm in the DOT™ group and by 0.08 ± 0.08 mm in the control group. No significant differences were observed between the groups in myopia progression (-0.04 D) or axial elongation (-0.03 mm), indicating that there was no rebound effect after discontinuing DOT™ lenses. These six month results suggest that the myopia control benefits of DOT™ lenses are maintained after cessation of treatment, and further data will help to affirm this stability over the longer term.

Purpose: To investigate myopic progression in children following the cessation of Diffusion Optics Technology™ (DOT™) spectacle lenses after wearing for at least 4 years. 

Method: Children who completed the CYPRESS 4-year study (NCT04947735) were eligible to enroll in this 1-year cessation study (NCT05893979), in which the control group (n=22) continued wearing standard single vision spectacle lenses and the DOT™ group (n=32) were crossed over to standard single vision spectacle lenses.  To assess any possible rebound effect, measurement of cycloplegic refractive error (cSER) and axial length (AL) progression was planned at 6-monthly intervals.

Results: Fifty-four children (57% female) with a mean age of 13.54 (10.8 to 15.5) years enrolled in the study.  The baseline mean (±SD) cSER and AL for Test was -3.27 (2.01) D and 24.75 (1.03) mm and for Control -3.77 (1.28) D and 24.99 (0.73) mm. The current available interim sample included 41 children. After 6-months of wear, the mean ±SD myopia progression based on cSER difference for the original DOT™ group (n=24) was -0.12 ±0.23 D and for Control (n=17) was -0.16 ±0.19 D.  For axial length, the difference was 0.11±0.06 mm for the original DOT™ group and 0.08 ±0.08 mm for Control.  No significant differences in myopia progression (-0.04 D, 95% CI -0.18 to 0.09, p=0.56) and axial elongation (-0.03 mm, 95% CI -0.07 to 0.01, p=0.18) were found between the original DOT™ and Control groups.  

Conclusion: The interim results from this ongoing study suggest that neither myopia progression nor axial growth was faster for the subjects who discontinued DOT™ spectacle lens wear compared to those who continued to wear single-vision spectacles. These findings indicate DOT™ spectacle lens treatment benefit is retained after cessation of treatment. 

Authors: Lucill Wang¹, Marcella McParland¹

1. SightGlass Vision, TX, USA

This retrospective study assessed the effectiveness of DOT™ spectacle lenses in slowing myopia progression in Chinese children over a 12-month period in real-world clinical settings. Data from 147 children aged 5 to 16 were collected at baseline, 6 months, and 12 months after starting DOT™ lens wear. Mean progression in manifest spherical equivalent refraction (mSER) was minimal, with 0.02 D at 6 months and -0.04 D at 12 months. Axial length (AL) showed negligible growth, with 0.00 mm at 6 months and 0.04 mm at 12 months. Notably, 96.6% of children had myopia progression limited to -0.25 D or less at 6 months, and 87.3% at 12 months. Compared to untreated children in the SCORM study who served as a virtual control, DOT™ lenses reduced axial elongation by 84%. AL growth was 0.04 mm, which was even less than the physiological growth predicted for emmetropic eyes. These findings indicate that DOT™ spectacle lenses effectively slow myopia progression in clinical practice, reinforcing results from the randomized controlled trials.^6,7

Purpose: Diffusion Optics Technology™ (DOT™) spectacle lenses are designed to slow myopia progression by modulating retinal contrast.  The purpose of this study was to evaluate myopia progression observed in Chinese children wearing Diffusion Optics Technology (DOT™) spectacle lenses in a real-world clinical population for 12 months. 

Method: In this retrospective observational data collection, clinical records from 4 locations were reviewed to identify children who were prescribed with DOT™ spectacle lenses in China between June 2022 and May 2023 who had not received other myopia control treatment.  Data was collected at three time points: at DOT™ lens dispensing (baseline), 6-months and 12-months after DOT™ spectacle lens wear.  Changes from baseline in manifest spherical equivalent refraction (mSER) and axial length (AL) progression were analyzed at 6 and 12 months of DOT™ spectacle lens wear. To adjust for between-person variability in follow-up times, the observed change in each outcome measure was standardized to 6-and12-month changes from baseline.  For comparison, age matched untreated myopic eye data from the Singapore Cohort Study of the Risk Factors for Myopia (SCORM) was used as a virtual control.

Results: A total of 147 unique patient records were identified and included for analyses. Mean age was 10.01 years at baseline (range 5 to 16 years), male n=76, 51.7%. Baseline mean mSER ± SD was -2.54 ± 1.52 D (range -0.50 to -6.88 D) and mean AL was 24.79 ± 0.93 mm (range 21.63 to 28.20 mm).  Changes in both mSER and AL at 6 and 12 months were not significant (p >0.4).  After 6-months of DOT™ spectacle lens wear, mean progression was 0.02 ± 0.17 D in mSER and 0.00 ± 0.17 mm in AL.  After 12-months mean progression was -0.04 ± 0.29 D in mSER and 0.04 ± 0.17 mm in AL.   mSER progression was limited to -0.25 D or less in 96.6% of children after 6 months and 87.3% after 12 months of wear. 

SCORM age-matched untreated myopic eye 1-year growth data predicted mean annual axial elongation of 0.25 mm. Comparing to SCORM data, DOT™ lenses slowed AL progression by 84% (0.21 mm). The observed 0.04 mm AL elongation in DOT™ lens wearers was negligible and slightly less than the age-matched emmetropic eye growth (considered physiological eye growth) predicted by SCORM data (0.09 mm).  

Conclusion: Real world use of DOT™ spectacle lenses demonstrate that contrast modulation spectacles successfully slowed the progression of myopia compared to modelled untreated myopic children. These real-world results demonstrate DOT™ spectacle lenses effectively slow myopia progression in clinical practice. 

Authors: Kylvin Ho¹, Ji Youn Kim¹, Kyleon Ho¹, Debbie Laughton ², Martin Rickert³ 

1. C U Vision Optometrists, Burnaby, British Columbia, Canada
2. SightGlass Vision, Dallas, TX
3. Indiana University, Bloomington, IN

This study evaluated the 1-year efficacy of two myopia control spectacle lenses—Diffusion Optics Technology™ with contrast modulation (MC1) and Defocus Incorporated Multiple Segments (MC2)—in slowing myopia progression in younger children. 80 Asian Canadian children aged 6 to 8 were assigned either MC1 (n=45) or MC2 (n=35) lenses. Myopia progression was assessed using manifest spherical equivalent refraction (mSER) and axial length (AL). After 1 year, the MC1 group showed significantly less myopia progression (-0.32 D) compared to the MC2 group (-0.58 D), with MC1 being 45% more effective. Similarly, axial elongation was lower in the MC1 group (0.19 mm) compared to the MC2 group (0.32 mm), with MC1 being 41% more effective. Over half of the MC1 group (56.7%) had no myopia progression, compared to 38.6% in the MC2 group. These findings suggest that DOT™ lenses were more effective in slowing myopia progression and axial elongation compared to Defocus Incorporated Multiple Segments (DIMS) lenses. The original randomized controlled trial for the DIMS lenses involved children in an older age range (8 to 13 year) compared to this trial, however it was noted that efficacy was lower for the younger children under 10 years of age.⁸ Therefore, it is important to note the specific research parameters under which myopia control spectacle lenses were investigated: if a patient falls outside the age or refraction range studied, expectations for treatment efficacy may need to be adjusted accordingly.

Aim: To evaluate the 1-year efficacy of two myopia control spectacle lenses: Diffusion Optics Technology™ with contrast modulation (MC1) and Defocus Incorporated Multiple Segments (MC2) to slow myopia progression in younger children.

Methods: Eighty Asian Canadian children (53% Male) aged 6 to 8 years (MC1 7.1 ± 0.9; MC2 7.5 ± 0.7) at initiation of intervention with myopia of -0.50 to -5.63 D (mean -1.99 ± 1.01), astigmatism ≤2.50 D and axial length of 21.8 to 25.9 mm (mean 23.9 ± 0.8) were dispensed with MC1 (n=45) and MC2 (n=35) spectacle lenses.  Myopia progression was determined using Manifest spherical equivalent refraction (mSER) and axial length (AL) measurements at baseline and 1-year interval. 

Results: After 1 year, the mean (±SE) of the myopic progressions for mSER were -0.32±0.05D in the MC1 and -0.58±0.09D in the MC2, with a mean difference of 0.26D (95% CI [-0.46, -0.06], p = 0.011) or 45% better for MC1.  Efficacy measured using AL was 0.19±0.03 mm in the MC1 versus 0.32±0.04 mm in the MC2, with a mean difference of 0.13 mm (95% CI [0.04, 0.22], p =0.006) or 41% better for MC1.  This result is consistent with age-matched AL data from a multicenter randomised controlled clinical trial (CYPRESS) at 1 year for MC1 (n=49) of 0.18 ±0.02 mm versus the control AL (n=51) which was 0.35 ±0.03 mm.   After adjusting for age, MC1 still has significantly lower mean values for both mSER and AL compared to the MC2 (p=0.005 and p<0.001, respectively).  Additionally, 56.7% of children who wore MC1 had no myopia progression, compared to 38.6% for those who wore MC2.

Conclusion: In this clinical practice with younger children, spectacle lenses using contrast modulation (MC1) were more effective in slowing myopia progression and axial elongation compared with the defocus-based myopia control spectacle lenses.

Authors: Rachel Langan,¹ Maureen Neitz, ¹ Jay Neitz, ¹ James Kuchenbecker, ¹ and Dragos Rezeanu¹

1. University of Washington

This study explored the hypothesis that high-contrast images from near work, such as reading and screen use, contribute to myopia by overstimulating peripheral midget bipolar cells which are thought to be a signal for the eye to elongate, as part of a visual feedback mechanism. DOT™ lenses, designed to mimic natural contrast, were tested for their potential to reduce this effect. Using models of the human retina and modulation transfer functions (MTFs) to simulate visual stimuli and its effect on midget bipolar cells, the study found that high-contrast text significantly activates peripheral midget bipolar cells, while natural scenes produce minimal activation. Lowering contrast reduced this activation to levels similar to natural distant scenery without compromising readability. The results support the concept that near work induces myopia through overstimulation of peripheral retinal cells, and that DOT™ lenses may help mitigate this effect. This study adds to the body of work exploring aetiology of myopia.

Purpose: Although controversial, it seems clear that near work is a causal factor for myopia. Diffusion Optics Technology (DOT™) lenses, are a myopia control design based on contrast theory, shown to be effective in clinical trials. DOT™ lenses are proposed to mitigate the myopiagenic effects of near work by mimicking natural contrast. This study aims to test the hypothesis that near work causes myopia because high-contrast images from screens and reading drive the activity of peripheral midget bipolar cells excessively, signaling eye growth. In turn, the activity is proposed to be reduced by DOT™ lenses to levels like those produced by natural stimuli.  

Methods: At the level of human midget ganglion cells, the convergence of cones increases with retinal eccentricity, resulting in a rapid decrease in visual acuity. Midget bipolar cells are contrast detectors, and unlike midget ganglion cells, they have a 1:1 ratio with cones in the periphery. They consequently support higher visual acuity than the peripheral ganglion cells. The high acuity of midget bipolars may be available to the emmetropization mechanism. Thus, the high-contrast detail of images, such as that of text that fills the peripheral retina during close work could signal eye growth, leading to myopia. To find out, we developed models of the peripheral midget bipolar cell receptive fields from known human retinal anatomy and physiology. Next, we used the models to derive spatial modulation transfer functions (MTFs) for the midget bipolar cells, combined with an optical spatial MTF for the human eye to produce a filter for determining the relative activation of peripheral midget bipolar cells by visual stimuli. We computed power spectra of images using the 2D Fast Fourier Transform in MATLAB, which were transformed into 1D spectra by rotationally averaging the power values. Multiplying the 1D power spectra by the MTF of bipolar cells and summing the products gives the relative activation of midget bipolar cells produced by a visual scene.   

Results: The modulation transfer function of peripheral midget bipolar cells is well-matched to the power spectra of images from screens at normal viewing distances. The high contrast of black-on-white text on screens produces high activity in the midget bipolar cells. In contrast, simulations of the out-of-focus images of distant scenery that fill the peripheral retina in natural scenes when a person is near accommodated produce minimal activation of the midget bipolar cells. Even for simulations of images viewed with the far-accommodated eye, distant natural scenery produces less activation of the midget bipolar cells than screen images viewed at near. Lowering the contrast of screen images, as done by the SightGlass Vision DOT™ lenses, reduces the activation of midget bipolar cells to levels approaching that of distant scenery outdoors while the text remains clear and readable.  

Conclusions: The results are consistent with the hypothesis that near work causes myopia because high-contrast images from screens and reading excessively drive the activity of peripheral midget bipolar cells, which signal axial elongation.

Authors: Alfredo Desiato¹, Reena Rani Anand¹, Inderjit Chatha¹, Nicola S. Logan¹, Amy L. Sheppard¹, James S. Wolffsohn¹, Deborah Laughton², Leon N Davies¹

1. Optometry & Vision Science Research Group, School of Optometry, Aston University, Birmingham, United Kingdom
2. SightGlass Vision, Inc., Texas, USA
   
   

Choroidal thickness is increasingly being studied for its potential role in regulating eye growth, particularly in relation to myopia progression. This study investigated short-term changes in subfoveal choroidal thickness (SFCT) in children using different types of myopia control spectacle lenses. Seven children aged 7 to 12 years wore three types of lenses—Diffusion Optics Technology™ (DOT™), Defocus Incorporated Multiple Segments (DIMS), and single vision (SV) lenses—in a randomized crossover design, each for one week. SFCT measurements were taken before and after the lens wear using SD-OCT. Both DOT™ and DIMS lenses significantly increased SFCT after 1 week compared to baseline and SV lenses, with increases of 16.94µm and 20.28µm, respectively. These results suggest that both contrast modulation (DOT™) and defocus (DIMS) can elicit choroidal thickening in myopic children. The study highlights the importance of choroidal thickness as a biomarker in myopia control and suggests that short-term increases in choroidal thickness may play a role in reducing the risk of axial elongation and myopia progression.

Purpose: The choroid is believed to play a crucial role in regulating visually guided eye growth, primarily through variations in choroidal thickness in response to the retinal image. It has been suggested that an increase in choroidal thickness may contribute to arresting eye growth and, therefore, the progression of myopia. Additionally, accelerated axial elongation has been associated with a smaller increase in subfoveal ChT (SFCT). This study tests the hypothesis that short-term SFCT changes in children’s eyes can be elicited by myopia control spectacle lenses irrespective of design, by assessing the alterations in SFCT.

Methods: Eligible myopic children (cycloplegic autorefraction SER >-8.00D and ≤-0.50D), aged 6 to 12 years, with astigmatism <2.00DC, anisometropia ≤ 2.00D, and best corrected VA of 0.10 logMAR or better, were dispensed three study lenses: Diffusion Optics Technology™ (DOT™) lenses, designed to control myopia by modulating retinal contrast; Defocus Incorporated Multiple Segments (DIMS) lenses, designed to modulate retinal defocus; and single vision (SV) lenses, as a control. The spectacle lenses were worn in a randomized crossover design, following baseline measurements.

SFCT measurements were obtained at baseline and after 1-week of wearing each type of lens using an Enhanced Depth Imaging Mode of a non-contact SD-OCT (SPECTRALIS, Heidelberg) along six reference meridians, spaced 30° apart. Immediately preceding all SFCT measures, participants were supervised viewing a distance vision task for 30 minutes, The SFCT values for each meridian were determined using semi-automated segmentation analysis software (MATLAB, MathWorks), and averaged for each participant.

Results: Seven participants (4M, 3F), with a mean age of 10 years (ranging from 7 to 12 years) and mean cycloplegic autorefraction SER of -2.00D (ranging from -3.63D to -0.64D), completed the study. The use of DOT™ and DIMS lenses resulted in similar significant increases in SFCT after 1-week of continuous use compared to both baseline values and the use of the SV lens (all p<0.05), with an overall mean wearing time >12 h per day. Specifically, the average increase for DOT™ lenses was 16.94±14.51µm from the baseline and 16.33±20.11µm compared to the SV lenses. Analogously, DIMS lenses showed increases of 20.28±18.08 and 19.67±23.59µm, respectively, indicating that different strategies in modifying retinal images can elicit significant increases in choroidal thickness in myopic children.

Meridional analysis revealed that, among the six meridians investigated, the SFCT values extrapolated from the vertical (at a 90° angle) were corresponding to the averaged SFCT values in revealing the significant differences found for across the study lenses in the cohort. Moreover, the interclass correlation coefficient for average measurements between the vertical meridian and the averaged SFCT ranged from 0.996 to 0.999 (all p<0.05), suggesting that this measurement alone may be reliable indicator of SFCT change.

Conclusions: Both DOT™ and DIMS lenses produce a significant increase in SFCT after 1-week of wear, suggesting choroidal thickening can be elicited by different ways of modifying the retinal image. Furthermore, vertical meridian acquisition alone may be a reliable surrogate for overall SFCT change.

Authors: Amy L. Sheppard¹, Deborah Laughton², James S. Wolffsohn¹

1. Optometry & Vision Science Research Group, School of Optometry, Aston University, Birmingham, United Kingdom

SightGlass Vision, Inc., Texas, USA

Emmetropic eye growth is an increasingly used metric for myopia control efficacy in clinical trials to account for growth related to emmetropisation.⁹ It has been suggested that continued refractive progression may occur even if axial length growth slows to emmetropic rates due to the lack of compensation by the crystalline lens in a myopic eye. This study evaluated the effectiveness of DOT™ spectacle lenses in slowing myopia progression by assessing refractive and structural changes over 3 years in myopic children aged 6 to 7 years. The trial involved 30 children wearing DOT™ lenses and 27 wearing standard single-vision lenses. Results showed that the DOT™ group experienced significantly slower AL growth (0.70 mm) compared to the Control group (1.03 mm), as well as reduced myopic refractive progression (-0.89 D vs -1.72 D). Despite this, there were no major differences in anterior eye biometry changes between groups. The study also found that changes in the crystalline lens did not fully compensate for ongoing axial elongation in myopic eyes. These findings suggest that DOT™ lenses are effective in reducing myopia progression and that the crystalline lens is unable to completely counterbalance eye growth in myopic eyes.

Purpose: Slowing axial length growth to emmetropic eye levels is often considered a target for myopia control therapies. It has been hypothesised that even if this target is achieved, myopic refractive progression may still occur due to the inability of the crystalline lens to compensate for axial elongation in a myopic eye. The purpose of this research was to evaluate refractive and structural changes in children wearing Diffusion Optics Technology (DOT™) spectacle lenses, and compare with ocular component growth in age-matched emmetropic eyes.

Method: At 14 North American sites, myopic children were enrolled in a 3-year randomised, controlled, double-masked clinical trial (NCT03623074). Spectacle lenses designed to modulate retinal contrast (DOT™ 0.2) and standard single-vision spectacle lenses (Control) were dispensed. Ocular biometry and cycloplegic SER were measured at baseline and annually for 3-years. Changes in Anterior Chamber Depth (ACD), Lens Thickness (LT), Vitreous Chamber Depth (VCD) and Axial Length (AL) were compared to age-matched emmetropic eye growth data modelled from the Orinda Longitudinal Study of Myopia (OLSM). The age range analysed was restricted to children aged 6 to 7 years at baseline (n=30 DOT™ 0.2, n=27 Control) due to the well-established changes in ocular component growth trajectory beyond age 9 to 10 years.

Results: After 3 years, least square mean (± SE) AL progression was slowed by 0.33mm in the DOT™ 0.2 group compared to the Control group (0.70±0.07mm vs 1.03±0.07mm, p=0.0011). Least square mean cSER progression was slowed by 0.84D in the DOT™ group compared to the Control group (-0.89±0.17D vs -1.72±0.17D, p=0.0008). 

Despite lower VCD elongation in the DOT™ 0.2 group compared to the Control group (0.69±0.29mm vs 0.98±0.38mm, p<0.0001), changes in keratometry and anterior eye biometry (corneal thickness, ACD and LT) were similar between groups (all p>0.10). 

Baseline modelled emmetropic eye LT (3.53±0.02mm) was significantly thicker than the DOT™ 0.2 (3.42±0.12mm, p=0.0006) and Control (3.44±0.13mm, p=0.0026) groups. Compared to modelled emmetropic eye growth, thinning of the crystalline lens over 3 years was approximately 60% less in the DOT™ and Control groups (p<0.0001): mean change in LT of modelled emmetropic group -0.12mm, DOT™ group -0.05±0.06mm, Control group -0.05±0.08mm. Compared to 3-year modelled emmetropic growth (0.48mm), AL growth was 46% greater in the DOT™ 0.2 group and 115% greater in the Control group.   

Conclusions: Young children wearing DOT™ spectacle lenses demonstrated significantly less myopia progression than the Control group after 3-years of wear. Ocular biometric findings suggest posterior eye growth did not significantly impact anterior eye axial measures beyond a limit. Comparison to modelled emmetropic eye growth supports the hypothesis that crystalline lens structural changes are unable to compensate for ongoing AL elongation in myopic eyes.   

Authors: James S. Wolffsohn,¹ Reena Rani Anand,¹ Inderjit Chatha,¹ Hiu Yan Lam,¹ Nicola S. Logan,¹ Amy L. Sheppard,¹ Debbie Laughton,² Leon N. Davies¹  

1. Optometry & Vision Science Research Group, School of Optometry, Aston University, Birmingham, United Kingdom
2. SightGlass Vision, Inc., California, USA

This study assessed how glare and low luminance conditions impact contrast sensitivity in various myopia control spectacle lenses. Twenty myopic adults (corrected to functional emmetropia using spherical soft contact lenses) wore four types of lenses—Diffusion Optics Technology™ (DOT™), Defocus Incorporated Multiple Segments (DIMS), Highly Aspherical Lenslets (HAL), and standard single-vision lenses—in a randomized crossover trial. Contrast sensitivity was measured under photopic and mesopic conditions, with and without a glare source, through both the central and peripheral lens zones. Results showed that glare and mesopic lighting significantly reduced contrast sensitivity, particularly when viewing through the peripheral treatment zones of myopia control lenses. While there was no significant difference between lenses with glare, under mesopic conditions, single-vision lenses performed better in the central zone. DOT™ lenses performed comparably to single-vision lenses in the peripheral zone and better than HAL and DIMS lenses. This suggests that DOT™ lenses offer improved performance in varying lighting conditions, making them a strong option for patients who may be particularly sensitive to contrast changes in different environments or who regularly engage in visually demanding tasks in low-light environments.

Purpose: To assess the effect of glare and the luminance level of a contrast sensitivity function assessment test to differentiate between myopia control spectacle lens designs.

Methods: Twenty myopic (MSE -4.25D to -0.50D) adults (16F); aged 18-30 years, rendered functionally emmetropic with spherical soft contact lenses wore, sequentially, lenses with Diffusion Optics Technology (DOT™), Defocus Incorporated Multiple Segments (DIMS), Highly Aspherical Lenslets (HAL) and standard single vision plano spectacle lenses in a prospective, single-visit, double-blind, four-way randomised crossover study. Contrast sensitivity function was assessed monocularly at 40cm with the tablet format Aston Contrast Sensitivity test in photopic condition, with strip lights attached either side of the tablet (115,000 cd/m² at an angle of ±12.3°) and under mesopic conditions, assessed viewing through the lens centre and/or periphery (lens decentred 10mm from the optical centre).

Results: The addition of a glare source (F=6.273, p=0.022), or decreasing the luminance from photopic to mesopic (F=103.264, p<0.001) reduced contrast sensitivity. Contrast sensitivity was lower when viewing through the peripheral treatment zone compared to the central clear zone (F=54.092, p<0.001), both with glare and a reduction to mesopic luminance (both p<0.001) with all the lenses tested. There was no difference between the lenses worn with glare (F=3.088, p=0.055), but there was with a reduction to mesopic lighting levels (F=6.095, p=0.005); for the central clear zone, the standard single vision lens performed better than the three myopia control lens designs (p<0.001), but for the peripheral treatment zone, the DOT™ lenses performed similarly to the standard single vision lenses (p=0.537), and better compared to the HAL and DIMS lenses (p<0.01).

Conclusion: The addition of glare and reducing the luminance to mesopic levels allowed the contrast sensitivity function to differentiate between single vision and within myopia control spectacle lenses.