Lower sensitivity to peripheral hypermetropic defocus due to higher order ocular aberrations

Abstract

Citation information: Papadogiannis P, Romashchenko D, Unsbo P & Lundstr€ om L. Lower sensitivity to peripheral hypermetropic defocus due to higher order ocular aberrations. Ophthalmic Physiol Opt 2020; 40: 300-307. https://doi.Author contributions: PP and LL: involved in all aspects of study conception and design; data acquisition, analysis and interpretation; and drafting and critically revising the manuscript. DR: involved in data acquisition, analysis and interpretation; and critically revising the manuscript. PU: involved in study design and critically revising the manuscript. AbstractPurpose: Many myopia control interventions are designed to induce myopic relative peripheral refraction. However, myopes tend to show asymmetries in their sensitivity to defocus, seeing better with hypermetropic rather than myopic defocus. This study aims to determine the influence of chromatic aberrations (CA) and higher-order monochromatic aberrations (HOA) in the peripheral asymmetry to defocus. Methods: Peripheral (20°nasal visual field) low-contrast (10%) resolution acuity of nine subjects (four myopes, four emmetropes, one hypermetrope) was evaluated under induced myopic and hypermetropic defocus between AE5 D, under four conditions: (a) Peripheral Best Sphere and Cylinder (BSC) correction in white light; (b) Peripheral BSC correction + CA elimination (green light); (c) Peripheral BSC correction + HOA correction in white light; and (d) Peripheral BSC correction + CA elimination + HOA correction. No cycloplegia was used, and all measurements were repeated three times.Results: The slopes of the peripheral acuity as a function of positive and negative defocus differed, especially when the natural HOA and CA were present. This asymmetry was quantified as the average of the absolute sum of positive and negative defocus slopes for all subjects (AVS). The AVS was 0.081 and 0.063 logMAR/ D for white and green light respectively, when the ocular HOA were present. With adaptive optics correction for HOA, the asymmetry reduced to 0.021 logMAR/D for white and 0.031 logMAR/D for green light, mainly because the sensitivity to hypermetropic defocus increased when HOA were corrected. Conclusion: The asymmetry was only slightly affected by the elimination of the CA of the eye, whereas adaptive optics correction for HOA reduced the asymmetry. The HOA mainly affected the sensitivity to hypermetropic defocus.

Foveal and peripheral visual quality and accommodation with multifocal contact lenses

“…The psychophysical procedure to obtain the low-contrast resolution thresholds was implemented in MATLAB and Psychophysics toolbox, following the same process as described earlier [33]. The low-contrast resolution acuity task was chosen because it is limited by optical properties and not by the neural sampling also in the periphery [34,35].…”

Adaptive optics visual simulators: a review of recent optical designs and applications [Invited]

“…12 . The specific aims of the research projects are (1) to improve optical correction designs by better understanding the optical limitations of peripheral vision [ 107 – 112 ], (2) to understand and optimize the optical treatment effect of myopia control interventions [ 113 ], and (3) to improve the remaining peripheral vision for people with central visual field loss through optical correction [ 114 ].…”