Relationship between visual acuity and other optical parameters in no presbyopic eyes

Abstract

Purpose To study the relationship between visual acuity (VA) and fluctuation of accommodation and aberrometric data in a population of no presbyopic eyes. Methods Forty‐two no presbyopic eyes with natural pupil and scotopic lighting conditions were involved in the study. Subjects were studied with an autorefractor to determine the refraction and accommodation fluctuations, a ray tracing aberrometer to measure the refraction as well as aberrometric data, and a system to generate charts and determine the subjective refraction and the AV. The equipments were calibrated with an artificial eye before the tests were done. The subjects were divided in several subgroups of 1) subjective refraction (≥|‐0.50|D or <|‐0.50|D); 2) fluctuation of accommodation (≤0.1D or >0.1D) and 3) RMS of different high order (HO) aberrations: 3a) RMS of HO total (≤0.25µm or >0.25µm), 3b) RMS of spherical aberration (≤0.15µm or >0.15µm), 3c) RMS of coma (≤0.15µm or >0.15µm) and 2d) RMS of trefoil (≤0.15µm or >0.15µm) Results The mean value for VA was 1.28 and 0.16 D for fluctuations of accommodation. No significant differences among fluctuations of accommodation and VA were found in any group. We found normal values about RMS of HO (0.34 μm), RMS of coma (0.19 μm), RMS of trefoil (0.17 μm) and spherical aberration (0.11 μm). No differences between RMS and VA were found in any group. A moderate correlation (R2=0.19) between the VA and the spherical aberration was observed. Conclusion The values of fluctuation of accommodation and aberrometric data were within normal ranges reported in the literature. Differences between VA and other optical parameters were not found.

Comparison of a Novel Binocular Refraction System with Standard Digital Phoropter Refraction

“…New technologies may differ from existing instrumentation in their setup and subject positioning. Participant physical comfort using new instrumentation may be assessed by ranking instrumentation from most to least comfortable or assessing visual comfort comparison on a numbered scale 8,22 …”