Anglia Ruskin Research Online (ARRO)
Browse

File(s) under permanent embargo

The Effects of Blur and Eccentric Viewing on Adult Acuity for Pediatric Tests: Implications for Amblyopia Detection

journal contribution
posted on 2023-09-01, 13:55 authored by Monika A. Formankiewicz, Sarah J. Waugh
Purpose.: The detection of amblyopia in children relies on an accurate assessment of visual acuity. Visual deficits in anisometropic and strabismic amblyopia are different, but the influence of chart design, in particular position, and type of crowding features on visual acuity in the two types of amblyopia, is not clear. Certain aspects of amblyopic spatial vision are mimicked in healthy individuals by imposing increasing levels of blur and retinal eccentricity. We measured the effects of these conditions on visual acuity in healthy adults, with crowded and uncrowded vision tests. Methods.: Visual acuity was measured under conditions of blur (0–4 D) and eccentric viewing (0–5 degrees) using high-contrast optotypes derived from common children's acuity charts. Optotypes were presented in isolation, in commercially available crowded configurations, and in configurations with closer target-flanker separations than those currently available. Results.: Dioptric blur had similar degradative effects on crowded and isolated visual acuity (P > 0.05), whereas eccentric viewing resulted in a larger deterioration of visual acuity for crowded tests (E 2 of 0.86–1.06) than for isolated optotypes (E 2 of 1.57–1.72) (P < 0.05). Maximum crowding effects occurred for closer target-flanker separations than those currently used commercially. Conclusions.: In so far as blur and eccentric viewing mimic spatial acuity deficits in amblyopia, the results suggest that crowded tests might be of limited value in the detection of anisometropic amblyopia, but should be valuable in the detection of strabismic amblyopia. Crowding effects would be greater if flanking features were placed closer to the target than they currently are in commercially available charts.

History

Refereed

  • Yes

Volume

54

Issue number

10

Page range

6934-6943

Publication title

Investigative Ophthalmology & Visual Science

ISSN

1552-5783

Publisher

ARVO

File version

  • Accepted version

Language

  • eng

Legacy posted date

2015-03-10

Legacy creation date

2017-10-16

Legacy Faculty/School/Department

ARCHIVED Faculty of Science & Technology (until September 2018)

Usage metrics

    ARU Outputs

    Categories

    No categories selected

    Keywords

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC