Analysis of the characteristics of pattern visual evoked potentials in different age groups of children with ametropic amblyopia

Abstract

Objective To analyze the characteristics of pattern visual evoked potentials (PVEPs) and the effect of age in children with ametropic amblyopia.Methods Ninety-two children (184 eyes) with hyperopic amblyopia (spherical equivalent refractions) were analyzed retrospectively.Subjects were categorized into three groups based on the best corrected visual acuity (BCVA): mild amblyopia group (0.8-0.6),108 eyes; moderate amblyopia group (0.5-0.2),65 eyes; severe amblyopia group (BCVA≤0.1),11 eyes.Each group was further divided into two subgroups based on age: ＜6 years and ≥6 years. PVEPs were collected with a visual electrophysiological examination system. The differences between the latency (LP100) and amplitude (AP100) of the PVEP among different amblyopie groups and age subgroups were compared statistically with a one-way ANOVA and an independent samples t test.Results With an increase in the degree of amblyopia, the LP100 of the PVEP increased and the AP100 of the PVEP decreased.The differences between groups in the LP100 of the PVEP were statistically significant (F=151.30,P＜0.01).The differences between every two groups were statistically significant (P＜0.01).The differences between groups in the AP100 of the PVEP were statistically significant (F=13.59,P＜0.05).The differences between severe amblyopia and the other two groups were statistically significant (P＜0.01),but no statistically significant differences were found between the moderate and mild groups.Within the mild and moderate amblyopic groups,the LP100 of the ≥6 years of age group were longer than those of the ＜6 years of age group,and the AP100 of the former were less than those of the latter.The differences were statistically significant (mild group: t=5.08, 7.45, P＜0.01; moderate group: t=4.68, 4.27, P＜0.01).The severe group showed similar results but without statistical analysis due to fewer cases.Conclusion The LP100 and AP100 of the PVEP can be used to objectively assess the degree of ametropic amblyopia in children while the influence of age should also be considered. Key words: Evoked potentials,visual; Refractive errors ; Amblyopia; Children ; Age