Reply to Letter to Editor: Choroidal Thickness in Pediatric Population

We thank Dr. Prousali Efthymia et al. for their perceptive comments on our research. Their letter concerned primarily regarding the trend of choroidal thickness changes during childhood. The main objective of our study was to characterize the distribution of choroidal thickness profile in healthy Iranian children and adults at different age groups from 4 to 60 years old.1 The different kinds of refractive errors were labeled for each age group. The purpose of the study necessitated performing the examinations on a large sample of subjects from childhood to adulthood with different types of refractive errors. One limitation of our study was that we could not easily find a large number of children up to 10‑year‑old with different types of refractive errors to include in the study. However, considering the poor cooperation of children in the prolonged process of examinations and compared with previous studies, the number of pediatric subjects in the present study seems to be reasonable.2,3 By considering age as a factor, we inevitably included 45 cases under the age of 10 years as the children’s group which was to some extent lower than the other age groups. Based on the present data, we found a decreasing trend in children that agree well with existing studies.3‑5 In line with our study, Nagasawa et al. found a significantly thicker choroidal profile in children compared with adults.6 However, in the discussion part of the paper, we stated that there were conflicting results regarding the effect of age on choroidal thickness in children.2,7,8 As an example, Bidaut‑Garnier et al. found a positive correlation between choroidal thickness and age in the pediatric population (R2 = 0.056, P = 0.0017).2 In another study, Read et al. found a significantly thinner choroid (337 ± 65 μm, P < 0.05) in 4- to 6-year-old children compared with 7- to 9-year-old children (337 ± 65 μm, P < 0.05).7 The discrepancies might be attributed to the different patient selection criteria, choroidal thickness measurement methods, and ethnicity variations. A key strength of the current research lies within the fact that we included both children and adult subjects, and hence, the sample size was much larger than was previously used in similar studies.