Association of choroidal thickness with eye growth: a cross-sectional study of individuals between 4 and 23 years

We aimed to evaluate the association of subfoveal choroidal thickness (SFCT) with age and to determine its relationship with axial length (AL) and ocular biometric parameters, in children and young adults during growth period.

One hundred and sixty patients (80 male, 80 female) aged between 4 and 23 years were included. Patients were classified into five groups according to their ages as group 1 (4-7 years of age), group 2 (8-11 years), group 3 (12-15 years), group 4 (16-19 years), and group 5 (20-23 years). SFCT was assessed using spectral-domain optical coherence tomography (3D OCT-2000). The measurements were taken at the same daytime (1000-1200 hours) to avoid diurnal fluctuation. Ocular AL and anterior segment parameters were measured using optical biometry (Lenstar LS900)).

The average SFCT was 308.1±47.6 μm, ranging from 206 to 410 μm. The mean SFCT values in group 1 to 5 were measured as 306.8±42.0, 297.8±48.1, 283.2±38.9, 326.9±57.4, and 325.8±35.9 μm, respectively. The mean CT of group 3 was significantly thinner than group 4 and 5 (P<0.05 for two groups), however, there was no statistical significance compared with group 1 (P=0.227) and group 2 (P=0.693). On stepwise regression analysis, age exhibited a positive association with SFCT (B=2.8, P<0.001) and AL exhibited a negative association with choroidal thickness (B=-16.7, P<0.001).

We found that SFCT shows no age-related difference until age of 15, whereas 16-23-year old participants had thicker SFCT compared with the younger ones. In that aspect, a thicker choroid associated with age in certain age groups suggests an age period of SFCT increase to a plateau in young adulthood. Larger studies are warranted to elucidate the age-related changes in SFCT in childhood, as improved evaluation of normal choroidal thicknesses during eye growth should assist in the diagnosis of choroidal abnormalities associated with eye disease.