Contrast Sensitivity and Low-Contrast Visual Acuity in Children With Low Vision

Area of Science:

• Ophthalmology
• Pediatric Vision
• Low Vision Research

Background:

• Low vision in children presents significant challenges in visual function assessment.
• Understanding contrast sensitivity (CS) and low-contrast visual acuities (LCVAs) is crucial for managing pediatric visual impairment.

Purpose of the Study:

• To investigate distance and near contrast sensitivity (CS) and low-contrast visual acuities (LCVAs) in children (5 to <16 years) with low vision across diverse eye diseases.
• To assess the repeatability of these visual function measures in the pediatric low vision population.

Main Methods:

• Recruited 782 children with low vision (visual acuity 0.3-1.3 logMAR or visual field MD worse than 12 dB).
• Assessed CS using Pelli-Robson tests and LCVAs at 5% and 2.5% contrast with LEA symbols.
• Evaluated repeatability in 134 children via repeated measures over ~3 months using Bland-Altman 95% limits of agreement (LoAs).

Main Results:

• Observed a broad range of CS (distance: 1.69-0.45 logCS, near: 1.73-0.15 logCS) and LCVA (0.80-1.54 logMAR at 5% contrast, 0.94-1.58 logMAR at 2.5% contrast) across 47 eye diseases.
• Found significant test-retest variability: LoAs were 0.44 logCS (distance), 0.54 logCS (near), 0.38 logMAR (5% LCVA), and 0.42 logMAR (2.5% LCVA).

Conclusions:

• Contrast sensitivity and LCVA impairments are highly variable among children with different eye diseases causing low vision.
• Clinically meaningful changes in CS (>0.45 logCS) or LCVA (>0.4 logMAR) should be considered in follow-up assessments due to substantial test-retest variability.