Peripheral Design of Progressive Addition Lenses and the Lag of Accommodation in Myopes

Evidence from animal and human studies suggests that ocular growth is influenced by visual experience. Reduced retinal image quality and imposed optical defocus result in predictable changes in axial eye growth. Higher order aberrations are optical imperfections of the eye that alter retinal image quality despite optimal correction of spherical defocus and astigmatism. Since higher order aberrations reduce retinal image quality and produce variations in optical vergence across the entrance pupil of the eye, they may provide optical signals that contribute to the regulation and modulation of eye growth and refractive error development. The magnitude and type of higher order aberrations vary with age, refractive error, and during near work and accommodation. Furthermore, distinctive changes in higher order aberrations occur with various myopia control treatments, including atropine, near addition spectacle lenses, orthokeratology and soft multifocal and dual‐focus contact lenses. Several plausible mechanisms have been proposed by which higher order aberrations may influence axial eye growth, the development of refractive error, and the treatment effect of myopia control interventions. Future studies of higher order aberrations, particularly during childhood, accommodation, and treatment with myopia control interventions are required to further our understanding of their potential role in refractive error development and eye growth.

Section: Hoas and Myopia Control Interventionsmentioning

confidence: 99%

Section: Spectacle Lenses: Bifocal and Progressive Addition Lensesmentioning

confidence: 99%

Higher order aberrations, refractive error development and myopia control: a review

Hughes

Vincent

Read

et al. 2020

“…The present study also highlighted the abnormal accommodative response of patients with TBI to five different stimulus levels. Normally, when viewing near targets, people under 40 years of age manifest a mild amount of accommodative lag 2017. However, with the accommodative stimulus increased, the TBI group presented more lag.…”

Section: Discussionmentioning

confidence: 99%

“…Normally, when viewing near targets, people under 40 years of age manifest a mild amount of accommodative lag. 37 However, with the accommodative stimulus increased, the TBI group presented more lag. We speculate that this was predominantly a consequence of accommodative fatigue.…”

Section: Table 2 Comparison Of Accommodation Function Values Betweenmentioning

confidence: 98%

Accommodation and stereopsis in adults with traumatic brain injury

Chen

Yang

et al. 2020

Background: Traumatic brain injury has many adverse effects on visual functions. The aim of this study is to evaluate accommodation, stereopsis deficits and visual symptoms in Chinese patients with traumatic brain injury. Methods: This is a cross-sectional study that included 22 patients with traumatic brain injury and 22 controls; the refractive status, stereoacuity, and accommodative ability of each subject were measured. Results: Patients with traumatic brain injury were significantly more symptomatic than controls (p < 0.001). Near stereoacuity thresholds were significantly elevated in patients with traumatic brain injury compared to controls (p < 0.001). Accommodative amplitude (right eye: p = 0.007; left eye: p = 0.01; both eyes: p = 0.002) and accommodative facility rates (right eye: p < 0.001; left eye: p < 0.001; both eyes: p < 0.001) were significantly lower in patients with traumatic brain injury, for whom there were no significant differences between the accommodative facility rates of the pre-and post-three-minute binocular flipper sessions (p = 0.51). Patients with traumatic brain injury showed greater accommodative lag to 2.5 D (p = 0.03), 3 D (p = 0.03), 4 D (p = 0.004) and 5 D (p = 0.001) stimuli, but not to the 2 D (p = 0.10) stimulus. The regression equation of accommodative lag to stimuli was steeper for the traumatic brain injury group (slope: p = 0.01; y-intercept: p < 0.0001). There were also significant correlations between visual symptoms and clinical findings including binocular accommodative amplitude (r = −0.480, p = 0.001), binocular accommodative facility (r = −0.445, p = 0.004) and stereopsis (r = 0.457, p = 0.002). Conclusion: Patients with traumatic brain injury have deficits in accommodation and stereopsis.

“…Thus, the near addition selected for a particular study may not be suitable for some of the recruited children . Additionally, it has been recently shown that not only the amount of addition but the distribution of optical power through the near vision zone of PALs can also influence accommodative responses …”

Section: Optical Strategies Of Myopia Controlmentioning

confidence: 99%

Optical and pharmacological strategies of myopia control

Kang

2018

Recent increases in global myopia prevalence rates have raised significant concerns as myopia increases the lifelong risk of various sight-threatening ocular conditions. This growing public health burden has generated significant research interests into understanding both its aetiology and developing effective methods to slow down or stop its development, methods collectively termed 'myopia control'. The growing body of research has demonstrated benefits of various optical and pharmacological treatments resulting in myopia control management increasingly becoming a part of main stream clinical practice. This review will discuss the peer-reviewed literature on the efficacy of various myopia control interventions including multifocal spectacles and contact lenses, orthokeratology and pharmaceutical eye drops, as well as potential future research directions.