Mechanism of optical treatments for myopia: Are lenslets joining the DOTs?

Ophthalmic and Physiological Optics, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 27, 2024

A recent randomised controlled trial (RCT) by Su et al.1 evaluated spectacle lenses with negatively-powered lenslets, rather than positively powered as a treatment for myopia. The new results al. may shed further light on the mechanism of action various forms optical treatments Most and contact lens-based interventions slowing myopia progression in children were designed to exert their therapeutic effect via 'simultaneous defocus', such that retina receives clear, in-focus image well myopically defocused image, is, an focused front retina.2, 3 In eyes fitted MiSight® (misight.com), DISC (Defocus Incorporated Soft Contact lens), centre-distance bifocal or orthokeratology lenses, central (foveal) region primarily sharply corrects child's on-axis refractive error. Meanwhile, mid-peripheral out-of-focus produced one more rings positive 'add' power.4, 5 retinal also receive lower contrast, from ring(s) plus power, while; clear regions correcting orthokeratology, ring power originates changes cornea after overnight lens wear; MiSight, zones altered curvature themselves. Instead this concentric design, most use array discrete, lenslets. Lenslets are small produce additional power; they typically cover about 50% surface. For example, MiyoSmart®, known Defocus Multiple Segments (DIMS) (hoyavision.com), there is containing ~400 circular 1 mm-diameter lenslets +4.00 D add compared portion lens. Stellest® (Essilor.com) highly aspheric achieve similar (known Highly Aspherical Lenslet Target [HALT] technology). An individual lenslet produces discrete patch defocus offset patches formed adjacent lenslets.6, 7 level across each influenced lenslet, but diffraction aberrations arising its transition carrier zone result myopic shell does not provide even if eye accommodates.8 By design do continuous provides accommodates (although quality be relatively poor9). Diffusion optics technology (DOT®) (sightglassvision.com) exploit different interventions.4, 10 DOT have like MiyoSmart Stellest lenses. However, instead remainder contains hundreds light-scattering elements reduce contrast retina.4, Although reduction analogous mild form deprivation, been found slow whereas deprivation stimulates development.11-13 cylindrical annular element (CARE®) (zeiss.com), utilises +8.00 micro-cylinders arranged rings, induce blur somewhat scatter CARE shown progression.14 As altering falling retina, DIMS alter peripheral which could relevance action.15 Where fit into picture? These authors wearing novel type surrounded −3.00 (so-called Negative Lenslet-ARray-Integrated [NLARI] lenses) (hkoptlens.com) effective +3.00 ('LARI' children's progression.1 This very expected receiving hyperopic defocus, since stimulus would accelerate progression.16 Leaving aside questions authors' rationale testing NLARI myopia, ethical risk–benefit balance these parsimonious explanation anti-myopia effects operate using introducing over retina. If indeed act mechanism, then supports suggestion Papadogiannis al.8 all lenslet-based spectacles reduction. One might begin question whether incorporating ring-based reduction, previously assumed.9 It will important find out confirmed future studies beneficial persist beyond 1-year, case DIMS, HALT spectacles.17-19 meantime, animal models great value distinguishing positive-power defocus. achieved, rearing animals exposed combination and/or scattering lenses,20 comparing under specific ambient lighting conditions.21 choice study important: tree shrews, guinea pigs chicks, area centralis towards periphery posterior segment, so it optically difficult create mimicked experienced children. marmosets macaque monkeys, fovea near pole, comparable situation humans. There remain unanswered mechanisms behind control interventions. serves reminder us always our assumptions. Jeremy A. Guggenheim: Conceptualization (equal); writing – original draft review editing (equal). Louise Terry: thank Dr. Thomas T. Norton insightful comments earlier manuscript. work was funded UK Research Innovation (UKRI) government's Horizon Europe funding guarantee [grant number EP/Y032292/1]. Funded European Union (Project 101119501 — MyoTreat HORIZON-MSCA-2022-DN-01). Views opinions expressed however those author(s) only necessarily reflect UKRI. Neither nor granting authority can held responsible them. Guggenheim, PhD, Professor Optometry Vision Sciences at Cardiff University, UK. He received his BSc PhD formerly Associate Head School Optometry, Hong Kong Polytechnic Kong. Guggenheim member CREAM Consortium genetics researchers Biobank Eye Consortium. Editor Investigative Ophthalmology Visual Science Editorial Board Member Ophthalmic Physiological Optics. recently served 'Focus Myopia' consensus committee United States, National Academies Science, Engineering Medicine. Terry, Lecturer Her main research interests ocular imaging, anterior eye, control. undertook her postgraduate University topic, 'An vivo investigation choroidal vasculature age-related macular degeneration'. centred around artificial intelligence detect classify 3-D OCT scans. qualified optometrist, Louise's has strong clinical focus includes both academic industry collaborators.

Language: Английский

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The Concept of Cone Opponency May Extend Beyond Accommodation, to Myopiagenesis and Emmetropization, for a Better Peripheral Defocus Lens

Asia-Pacific Journal of Ophthalmology, Journal Year: 2024, Volume and Issue: unknown, P. 100125 - 100125

Published: Dec. 1, 2024

Myopia has ever-rising prevalence in the past few decades globally. Its pathogenesis is still not adequately elucidated especially at signal transduction level. For environmental risk factors, there a large body of fragmented knowledge about visual inputs for accommodation, myopiagenesis and emmetropization, with latter two being essentially local processes. The red-green yellow-blue chromatic pathways, together underlying L-M S-(L+M) cone opponency, seem to be common denominator amongst them. In this review, experimental observational evidence are summarized delineate interplay This review may establish pivotal role longitudinal aberration (LCA) mechanistic approach future research myopia control. looks into processes specifically focusing on opponency vision as components. roles contrast onset development intriguing. How input pathways (specifically, blue-yellow opponency) contribute accommodation that trigger emmetropization mechanisms, thereby influencing eye growth patterns explored discussed. brief, manuscript delves physiology processing highlights foundational aspect science account "Go" or "Stop" signaling axial growth. It further proposes metric gauge myopia-inhibiting optical devices such peripheral defocus lenses, its best iteration. Future above-mentioned areas warranted.

Language: Английский

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Interactions between high-intensity light and unrestricted vision in the drive for hyperopia

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: June 11, 2024

Abstract PURPOSE To evaluate the impact of optical versus illuminance factors and their duration-dependency on lens-induced hyperopia (LIH) in chick eyes. METHODS Hyperopia was induced one eye chicks (10 groups, n=126) from day 1 (D1) post-hatching until D8 using +10 D lenses with fellow eyes as controls. One group served control without any interventions. Remaining groups were exposed to 2, 4 or 6 hours unrestricted vision (UnV), high intensity light (HL), both (HL +UnV). Ocular axial length (AL), refractive error, choroidal thickness measured days 1, 4, 8. Inter-ocular difference (IOD = experimental - contralateral eye) ± SEM used express outcome measures. RESULTS By D8, LIH decreased AL (-0.42±0.03 mm) produced hyperopic refraction (+3.48±0.32 D) thickening (+85.81±35.23 µm) (all, P<0.001). Exposure UnV reduced (i.e., refraction, shortening, thickening) a duration-dependent manner, whereas HL potentiated development manner. When combined, overpowered HL, resultant being close alone, except after hours, when HL+UnV shorter compared alone (P=0.03). CONCLUSION Daily exposure UnV, altered manner producing competing signals. The signal generated by generally stronger than combined exposure, yet longer durations affected drive for emmetropization UnV.

Language: Английский

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Autostereoscopic 3D viewing can change the dimensions of the crystalline lens in myopes

Ophthalmic and Physiological Optics, Journal Year: 2024, Volume and Issue: 44(6), P. 1309 - 1318

Published: July 9, 2024

Abstract Purpose Autostereoscopic displays have become increasingly common, but their impact on ocular dimensions remains unknown. We sought to identify changes in the crystalline lens induced by autostereoscopic three‐dimensional (3D) viewing. Methods Forty young adults (age: 22.6 ± 2.0 years, male/female: 15/25) were consecutively enrolled and randomly divided into two groups (3D two‐dimensional [2D] viewing groups) watch a 30‐min movie clip displayed 3D or 2D mode tablet computer. The thickness (LT), diameter, curvature, decentration tilt measured with anterior segment optical coherence tomography under both non‐accommodating (static) accommodating conditions. Results In static condition, LT decreased 0.03 mm ( p < 0.001) radius of curvature (ARC) increased 0.49 0.59 = post‐3D contrast, following viewing, ARC 0.23 0.25 0.001). Additionally, increase steep was greater high‐myopic eyes than low moderate myopic 0.04). When comparing accommodative (non‐accommodative) for (−0.03 0.05 mm, 0.02); while posterior (−0.14 0.20 0.006) diameter (−0.13 0.01) decreased. Conclusions Viewing could temporally decrease However, its long‐term effect requires further exploration.

Language: Английский

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Impact of Forms of Visual Attenuation on Short-Term Eye Changes Under Controlled Reading Visibility

Eye and Brain, Journal Year: 2024, Volume and Issue: Volume 16, P. 133 - 146

Published: Dec. 1, 2024

Animal studies have suggested that visual degradation impacts eye growth due to the attenuation of high spatial frequencies. However, influence perceptual visibility remains unclear in humans. The aim this study was investigate impact on attenuation-related changes during reading.

Language: Английский

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Effects of computer-generated patterns with different temporal and spatial frequencies on choroidal thickness, retinal dopamine and candidate genes in chickens wearing lenses

Frontiers in Medicine, Journal Year: 2024, Volume and Issue: 11

Published: Dec. 10, 2024

Changes in choroidal thickness (ChT) are proposed to predict myopia development but evidence is mixed. We investigated time courses of responses, following different types dynamic artificial stimulation chicks with and without spectacle lenses, as well changes retinal dopamine metabolism expression candidate genes.

Language: Английский

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Interactions Between High-Intensity Light and Unrestricted Vision in the Drive for Hyperopia

Investigative Ophthalmology & Visual Science, Journal Year: 2024, Volume and Issue: 65(14), P. 22 - 22

Published: Dec. 10, 2024

Purpose: To evaluate the impact of optical vs. illuminance factors and their duration-dependency on lens-induced hyperopia (LIH) in chick eyes. Methods: Hyperopia was induced one eye chicks (10 groups; n = 126) from day 1 after hatching until 8 using +10-diopter lenses with fellow eyes as controls. One group served control without any interventions. The remaining groups were exposed to 2, 4, or 6 hours unrestricted vision (UnV), high-intensity light (HL; 15,000 lux), both (HL + UnV). Ocular axial length (AL), refractive error, choroidal thickness measured days 1, 8. Inter-ocular difference (IOD experimental − contralateral eye) ± SEM used express outcome measures. Results: By 8, LIH decreased AL (−0.42 0.03 mm) produced hyperopic refraction (+3.48 0.32 diopters) thickening (+85.81 35.23 µm) (all P < 0.001). Exposure UnV reduced (i.e., refraction, shortening, thickening) a duration-dependent manner, whereas HL potentiated development manner. When combined, overpowered HL, resultant being close alone, except at hours, when shorter compared alone (P 0.03). Conclusions: Daily exposure UnV, altered manner producing competing signals. signal generated by generally stronger than combined exposure, yet longer durations affected drive for emmetropization UnV.

Language: Английский

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