To measure retinal thickness in eyes of children with regular visual development and in amblyopic eyes (distinguishing between mild and severe) by optical coherence tomography (OCT), establishing significant differences between them.
Methods.
Following our previous study, 192 eyes of children from 4 to 10 years old were examined: 68 with regular vision and 124 with ametropic amblyopia at the time of diagnosis (66 mild and 58 severe). The outside macular ring was analyzed by OCT, divided into 4 areas (superior, inferior, temporal and nasal). Effect of sex, age and refraction in retinal thickness obtained were studied.
Results.
All retinal areas in the various groups showed a high correlation between them, with rates ranging between 0.652 and 0.718 (all p <0.001). According to results, all retinal areas are thicker in amblyopic eyes than in normal ones (p <0.05 in the upper and nasal), especially in slight amblyopia, which is up to 4.5% thicker than in normal eyes (maximum 11 μm in the nasal area, p <0.001). Differences were greater in females (up to 5.9% thicker). The inferior area in hyperopic eyes proved to be thicker, with no differences according to age.
Conclusions.
Retinas of eyes with ametropic amblyopia have a more considerable retinal thickness than in a normal eye, at least in some areas. The severity of amblyopia and gender are factors of interaction, not of confounding.
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