Normative pediatric visual acuity using single surrounded HOTV optotypes on the Electronic Visual Acuity Tester following the Amblyopia Treatment Study protocol

Abstract

Purpose: To provide normative pediatric visual acuity data using HOTV optotypes presented on the Electronic Visual Acuity Tester following the Amblyopia Treatment Study (ATS) protocol.

Methods: Monocular testing was conducted on 384 healthy full-term children ranging from 3 to 10 years of age (mean, 5.4 years; SD, 1.8 years). A total of 373 children completed monocular testing of each eye. In addition, 23 adults (mean, 28.7 years; SD, 4.9 years) were tested for comparison. Both monocular visual acuity and interocular acuity differences were recorded.

Results: Mean visual acuity improved by slightly more than one line (0.12 logMAR) from 3 years of age to adulthood, increasing from 0.08 logMAR to -0.04 logMAR (F(6,400) = 26.3, p < 2.0 x 10(-26)). At all ages, mean interocular acuity difference was less than one line on a standard acuity chart (overall mean difference = 0.04 logMAR; SD, 0.06 logMAR).

Conclusions: These results represent the first normative data reported for HOTV optotypes using the ATS protocol on the Electronic Visual Acuity Tester. These data may play an important role in clinical practice, screening, and clinical research.

Figure 1

Normal visual acuity from participants in the present study and those in other studies plotted as a function of age. Note that visual acuity scores from 8–10 year-olds in the present study are combined and plotted at 9 years of age. (-●- Shea & Gaccon, 2006, Glasgow Acuity Cards; -○- Simmers et al., 1997, Glasgow Acuity Cards; -▼-Simmers et al., 1997, Sheridan-Gardiner; -■- Sheridan, 1960, HOTV; -▽- Slataper, 1950, Tumbling E; -□-Simons, 1983, Landolt C; -◇-Wiess, 1973, Tumbling E; -◆-Weiss, 1973, Tumbling E; - -Morad et al., 1999, Tumbling E; - -Morad et al., 1999, Linear Tumbling E; - - Brant & Novotny, 1976, Snellen; - - Brant & Novotny, 1976; Tumbling E; - - Current Study, HOTV).

Figure 2

Mean visual acuity from participants in the present study and from the fellow eye of children with amblyopia (fellow eye data are drawn from the Pediatric Eye Disease Investigator Group18). Bars represent one standard deviation from the mean.