Evaluation of objective and subjective binocular ocular refraction with looking in type

Megumi Fukushima; Masakazu Hirota; Takafumi Yukimori; Akio Hayashi; Yoko Hirohara; Makoto Saika; Kumiko Matsuoka

doi:10.1186/s12886-024-03449-y

Evaluation of objective and subjective binocular ocular refraction with looking in type

BMC Ophthalmol. 2024 Apr 16;24(1):170. doi: 10.1186/s12886-024-03449-y.

Authors

Megumi Fukushima¹, Masakazu Hirota^{2

3}, Takafumi Yukimori⁴, Akio Hayashi⁴, Yoko Hirohara⁴, Makoto Saika⁴, Kumiko Matsuoka⁵

Affiliations

¹ Division of Orthoptics, Graduate School of Medical Care and Technology, Teikyo University, Itabashi, Tokyo, Japan.
² Department of Orthoptics, Faculty of Medical Technology, Teikyo University, 2-11-1 Kaga, Itabashi, 173-8605, Itabashi, Tokyo, Japan. hirota.ortho@med.teikyo-u.ac.jp.
³ Department of Ophthalmology, School of Medicine, Teikyo University, Itabashi, Tokyo, Japan. hirota.ortho@med.teikyo-u.ac.jp.
⁴ Topcon Corporation, Itabashi, Tokyo, Japan.
⁵ Department of Orthoptics, Faculty of Medical Technology, Teikyo University, 2-11-1 Kaga, Itabashi, 173-8605, Itabashi, Tokyo, Japan.

Abstract

Background: This study aimed to compare the results of the Chronos binocular/monocular refraction system, that measures objective and subjective ocular refraction in one unit, to objective findings obtained from a conventional autorefractometer and a conventional subjective ocular refraction using a trial-frame in real space.

Methods: Twenty-eight healthy volunteers (21.2 ± 1.5 years old) were included in this study. Objective ocular refraction was measured using two tests: the Chronos binocular/monocular refraction system under binocular conditions and a conventional autorefractometer under monocular conditions. Subjective ocular refraction was measured using three tests: Chronos binocular/monocular refraction system under binocular, monocular conditions, and trial-frame in the real space under monocular conditions. The measurement distance was set to 5.0 m for each test. All ocular refractions were converted into spherical equivalents (SEs).

Results: The objective SE was significantly more negative with Chronos binocular/monocular refraction system under binocular condition (- 4.08 ± 2.76 D) than with the conventional autorefractometer under monocular condition (- 3.85 ± 2.66 D) (P = 0.002). Although, the subjective SE was significantly more negative with Chronos binocular/monocular refraction system under binocular condition (- 3.55 ± 2.67 D) than with the trial-frame in the real space under monocular condition (- 3.33 ± 2.75 D) (P = 0.002), Chronos binocular/monocular refraction system under monocular condition (- 3.17 ± 2.57 D) was not significantly different from that in trial-frame in real space under monocular condition (P = 0.33).

Conclusion: These findings suggest that the Chronos binocular/monocular refraction system, which can complete both objective and subjective ocular refraction tests in a single unit, is suitable for screening ocular refraction, although it produces slightly more myopic results. Furthermore, subjective ocular refraction testing accuracy in Chronos binocular/monocular refraction system can be equivalent to trial-frame in real-space testing by switching from binocular to monocular condition.

Keywords: Astigmatism; Autorefractometer; Ocular refraction; Refractive error; Visual acuity.

MeSH terms

Adult
Eye
Humans
Refraction, Ocular*
Vision Tests
Vision, Binocular*
Visual Acuity
Young Adult

Abstract

MeSH terms

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