To analyze choroidal sub-layers and vascular diameter in children, and to compare these choroidal features with those of adults.

Retrospective observational study.

This study included 96 eyes from 48 healthy children and 54 eyes from 27 healthy adults. The subfoveal choroidal thickness, large choroidal vessel layer thickness, medium choroidal vessel layer–choriocapillaris layer thickness, and large choroidal vessel diameter were estimated. The ratio of thickness of the large choroidal vessel layer to total choroidal thickness was calculated. The association between subfoveal choroidal thickness and large choroidal vessel layer, as well as ratio of thickness of the large choroidal vessel layer to total choroidal thickness, was analyzed. Furthermore, the ratio and choroidal vascular diameter were compared between children and adults.

The mean age was 6.7 ± 1.9 years and 30.7 ± 4.3 years in children and in adults, respectively. In children, the mean ratio was 0.71 ± 0.08 and the mean choroidal vascular diameter was 103.1 ± 16.0 μm. In adults, the values were 0.73 ± 0.08 and 122.5 ± 20.7 μm, respectively. The subfoveal choroidal thickness in children was significantly associated with the ratio (P < .001), whereas the association was not significant in adults (P = .173). The choroidal vascular diameter was significantly greater in adults than in children (P < .001). However, the ratio was not different between the 2 groups (P = .391).

Choroidal morphologic features are generally comparable between children and adults. Some differences between the 2 groups may reflect changes in choroidal morphology associated with aging.