VEP maturation and visual acuity in infants and preschool children.

PURPOSE

Visual processes continue to mature well into childhood, due to the development of the retina, optic nerve, visual pathway and visual cortex. Normal development of visual acuity and maturation of visual evoked potentials (VEPs) have been well studied, although rarely for their correlation. The purpose of this study was to investigate the same population of infants and preschool children for their VEP maturation to flash, pattern-reversal (reversal) and pattern-onset (onset) stimulation, which are normally used in our everyday clinical protocol, and to determine the relationships between the VEP parameters obtained and the development of visual acuity.

METHODS

Forty-one healthy children from 1.5 months to 7.5 years old were included. Their visual acuity for distance was tested with Teller Acuity Cards (<2 years of age) and Cambridge Visual Acuity Crowding Cards (>2 years of age). VEP latencies and amplitudes were evaluated to flash (P2 wave), reversal (P100 wave) and onset (C1 wave) binocular stimulation. For reversal and onset stimulation, checkerboard pattern (check) sizes of 25', 50' and 100' were used.

RESULTS

Age-dependent exponential decreases in latencies to flash, reversal and onset stimulation were seen. For amplitudes, there was an age-dependent increase only to onset stimulation. There was a significant correlation between VEPs and visual acuity (P < 0.05) for latencies to flash, reversal and onset stimulation and amplitudes to onset stimulation.

CONCLUSION

These findings indicate the expected maturation of flash, reversal and onset VEPs, and demonstrate their correlation to normal development of visual acuity. Maturation of VEP latencies is associated with development of visual acuity.