Macular choroidal thickness in unilateral amblyopic children

To investigate the choroidal thickness (CT) in children with amblyopia through spectral-domain optical coherence tomography (SD-OCT).

Thirty-seven children with unilateral amblyopia and 22 children with normal vision participated in the study. Cross-sectional images of the choroid of evaluated eyes were obtained by SD-OCT. The choroidal thickness was measured directly below the fovea and at eight other locations: 1 and 2 mm superior, temporal, inferior, and nasal to the fovea. The researchers compared the choroidal thickness among amblyopic eyes, fellow eyes of children with amblyopia, and the eyes of children with normal vision. Age, sex, refractive error, axial length, and best-corrected visual acuity were also recorded. A paired t-test was used to compare measurements between amblyopic eyes and fellow eyes in patients with amblyopia. A generalized estimating equation (GEE) was used to compare measurements among amblyopic eyes, fellow eyes, and control eyes, adjusting for the possible effects of age, sex, and axial length on CT. The correlation between choroidal thickness and other continuous variables was determined using the Pearson correlation coefficient.

The choroidal thickness at the fovea, 1 and 2 mm superior, 1 mm inferior, 1 mm nasal, and 1 mm temporal to the fovea was greater in amblyopic eyes and in fellow eyes of children with amblyopia than in the eyes of children with normal vision. The choroidal thickness at the fovea and 2 mm nasal to the fovea in amblyopic eyes was greater (P = 0.002, P = 0.043) than in the fellow eyes of the children with amblyopia. The subfoveal CT in amblyopic eyes negatively correlated with axial length (r = -0.501, P = 0.002), but did not correlate with spherical equivalent, logMAR visual acuity, or age.

In the subfoveal area, the choroid was thicker in amblyopic eyes than in fellow eyes in children with amblyopia. Furthermore, differences were found in the choroidal thickness in both eyes of children with amblyopia compared with participants with normal vision. A thicker choroid is somehow related to amblyopia, and this may be a useful diagnostic parameter for amblyopia.