Distance versus near visual acuity in amblyopia

J AAPOS. 2011 Aug;15(4):342-4. doi: 10.1016/j.jaapos.2011.05.004.


Purpose: There are conflicting reports about whether distance and near visual acuity are similar in eyes with amblyopia. The purpose of this study is to compare monocular distance visual acuity with near visual acuity in amblyopic eyes of children.

Methods: Subjects 2 to 6 years of age were evaluated in a randomized trial of amblyopia therapy for moderate amblyopia (20/40 to 20/80) due to anisometropia, strabismus, or both. Prior to initiating the protocol-prescribed therapy, subjects had best-corrected visual acuity measured with standardized protocols at 3 meters and 0.4 meters using single-surrounded HOTV optotypes.

Results: A total of 129 subjects were included. The mean amblyopic eye visual acuity was similar at distance and near (mean, 0.45 logMAR at distance versus 0.45 logMAR at near; mean difference, +0.00, 95% CI, -0.03 to 0.03). Of the 129 subjects, 86 (67%) tested within 1 line at distance and near; 19 (15%) tested more than 1 logMAR line better at distance, and 24 (19%) tested more than 1 logMAR line better at near. The mean visual acuity difference between distance and near did not differ by cause of amblyopia, age, or spherical equivalent refractive error.

Conclusions: We found no systematic difference between distance and near visual acuity in 2- to 6-year-old children with moderate amblyopia associated with strabismus and/or anisometropia. Individual differences between distance and near visual acuity are likely due to test-retest variability.

Trial registration: ClinicalTrials.gov NCT00094614.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Accommodation, Ocular / physiology*
  • Amblyopia / physiopathology*
  • Amblyopia / therapy*
  • Child
  • Child, Preschool
  • Humans
  • Severity of Illness Index
  • Strabismus / physiopathology
  • Strabismus / therapy
  • Vision Tests / methods*
  • Visual Acuity / physiology*

Associated data

  • ClinicalTrials.gov/NCT00094614