Technical Report: Repeatability of Contrast Sensitivity Test in Children.

Area of Science:

• Ophthalmology
• Pediatric Vision Science
• Visual Psychophysics

Background:

• Contrast sensitivity (CS) is vital for visual function but not routinely assessed in children.
• Simple visual acuity tests do not fully capture vision quality in pediatric populations.
• CS deficits are observed in amblyopic and premature children, highlighting the need for specialized testing.

Purpose of the Study:

• To evaluate the repeatability and establish the normal range of contrast sensitivity function in children aged 4-9 years.
• To assess the utility of the Topcon CC-100 instrument as a diagnostic tool for pediatric contrast sensitivity.

Main Methods:

• Contrast sensitivity was measured in 25 children (11 boys, 14 girls) with normal visual acuity.
• The Topcon CC-100 device was used to measure CS at spatial frequencies of 1.5, 3, 6, 12, and 18 cycles per degree (cpd).
• Two measurements were conducted 3 months apart to assess repeatability.

Main Results:

• Repeatability (coefficient of variation) was best at mid-range spatial frequencies (3 and 6 cpd).
• Variability was higher at low (1.5 cpd) and high (12, 18 cpd) spatial frequencies.
• Older children exhibited better repeatability, and a learning effect was noted between the two measurement sessions.

Conclusions:

• The Topcon CC-100 demonstrates variable repeatability across spatial frequencies in children.
• A learning effect may influence test results, suggesting caution when applying standard normality ranges.
• Further research is needed to refine CS testing protocols and establish age-appropriate normative data for children.